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/*!
* chai
* http://chaijs.com
* Copyright(c) 2011-2014 Jake Luer <jake@alogicalparadox.com>
* MIT Licensed
*/
module.exports = function (chai, _) {
var Assertion = chai.Assertion
, AssertionError = chai.AssertionError
, flag = _.flag;
/**
* ### Language Chains
*
* The following are provided as chainable getters to improve the readability
* of your assertions.
*
* **Chains**
*
* - to
* - be
* - been
* - is
* - that
* - which
* - and
* - has
* - have
* - with
* - at
* - of
* - same
* - but
* - does
* - still
*
* @name language chains
* @namespace BDD
* @api public
*/
[ 'to', 'be', 'been', 'is'
, 'and', 'has', 'have', 'with'
, 'that', 'which', 'at', 'of'
, 'same', 'but', 'does', 'still' ].forEach(function (chain) {
Assertion.addProperty(chain);
});
/**
* ### .not
*
* Negates all assertions that follow in the chain.
*
* expect(function () {}).to.not.throw();
* expect({a: 1}).to.not.have.property('b');
* expect([1, 2]).to.be.an('array').that.does.not.include(3);
*
* Just because you can negate any assertion with `.not` doesn't mean you
* should. With great power comes great responsibility. It's often best to
* assert that the one expected output was produced, rather than asserting
* that one of countless unexpected outputs wasn't produced. See individual
* assertions for specific guidance.
*
* expect(2).to.equal(2); // Recommended
* expect(2).to.not.equal(1); // Not recommended
*
* @name not
* @namespace BDD
* @api public
*/
Assertion.addProperty('not', function () {
flag(this, 'negate', true);
});
/**
* ### .deep
*
* Causes all `.equal`, `.include`, `.members`, `.keys`, and `.property`
* assertions that follow in the chain to use deep equality instead of strict
* (`===`) equality. See the `deep-eql` project page for info on the deep
* equality algorithm: https://github.com/chaijs/deep-eql.
*
* // Target object deeply (but not strictly) equals `{a: 1}`
* expect({a: 1}).to.deep.equal({a: 1});
* expect({a: 1}).to.not.equal({a: 1});
*
* // Target array deeply (but not strictly) includes `{a: 1}`
* expect([{a: 1}]).to.deep.include({a: 1});
* expect([{a: 1}]).to.not.include({a: 1});
*
* // Target object deeply (but not strictly) includes `x: {a: 1}`
* expect({x: {a: 1}}).to.deep.include({x: {a: 1}});
* expect({x: {a: 1}}).to.not.include({x: {a: 1}});
*
* // Target array deeply (but not strictly) has member `{a: 1}`
* expect([{a: 1}]).to.have.deep.members([{a: 1}]);
* expect([{a: 1}]).to.not.have.members([{a: 1}]);
*
* // Target set deeply (but not strictly) has key `{a: 1}`
* expect(new Set([{a: 1}])).to.have.deep.keys([{a: 1}]);
* expect(new Set([{a: 1}])).to.not.have.keys([{a: 1}]);
*
* // Target object deeply (but not strictly) has property `x: {a: 1}`
* expect({x: {a: 1}}).to.have.deep.property('x', {a: 1});
* expect({x: {a: 1}}).to.not.have.property('x', {a: 1});
*
* @name deep
* @namespace BDD
* @api public
*/
Assertion.addProperty('deep', function () {
flag(this, 'deep', true);
});
/**
* ### .nested
*
* Enables dot- and bracket-notation in all `.property` and `.include`
* assertions that follow in the chain.
*
* expect({a: {b: ['x', 'y']}}).to.have.nested.property('a.b[1]');
* expect({a: {b: ['x', 'y']}}).to.nested.include({'a.b[1]': 'y'});
*
* If `.` or `[]` are part of an actual property name, they can be escaped by
* adding two backslashes before them.
*
* expect({'.a': {'[b]': 'x'}}).to.have.nested.property('\\.a.\\[b\\]');
* expect({'.a': {'[b]': 'x'}}).to.nested.include({'\\.a.\\[b\\]': 'x'});
*
* `.nested` cannot be combined with `.own`.
*
* @name nested
* @namespace BDD
* @api public
*/
Assertion.addProperty('nested', function () {
flag(this, 'nested', true);
});
/**
* ### .own
*
* Causes all `.property` and `.include` assertions that follow in the chain
* to ignore inherited properties.
*
* Object.prototype.b = 2;
*
* expect({a: 1}).to.have.own.property('a');
* expect({a: 1}).to.have.property('b');
* expect({a: 1}).to.not.have.own.property('b');
*
* expect({a: 1}).to.own.include({a: 1});
* expect({a: 1}).to.include({b: 2}).but.not.own.include({b: 2});
*
* `.own` cannot be combined with `.nested`.
*
* @name own
* @namespace BDD
* @api public
*/
Assertion.addProperty('own', function () {
flag(this, 'own', true);
});
/**
* ### .ordered
*
* Causes all `.members` assertions that follow in the chain to require that
* members be in the same order.
*
* expect([1, 2]).to.have.ordered.members([1, 2])
* .but.not.have.ordered.members([2, 1]);
*
* When `.include` and `.ordered` are combined, the ordering begins at the
* start of both arrays.
*
* expect([1, 2, 3]).to.include.ordered.members([1, 2])
* .but.not.include.ordered.members([2, 3]);
*
* @name ordered
* @namespace BDD
* @api public
*/
Assertion.addProperty('ordered', function () {
flag(this, 'ordered', true);
});
/**
* ### .any
*
* Causes all `.keys` assertions that follow in the chain to only require that
* the target have at least one of the given keys. This is the opposite of
* `.all`, which requires that the target have all of the given keys.
*
* expect({a: 1, b: 2}).to.not.have.any.keys('c', 'd');
*
* See the `.keys` doc for guidance on when to use `.any` or `.all`.
*
* @name any
* @namespace BDD
* @api public
*/
Assertion.addProperty('any', function () {
flag(this, 'any', true);
flag(this, 'all', false);
});
/**
* ### .all
*
* Causes all `.keys` assertions that follow in the chain to require that the
* target have all of the given keys. This is the opposite of `.any`, which
* only requires that the target have at least one of the given keys.
*
* expect({a: 1, b: 2}).to.have.all.keys('a', 'b');
*
* Note that `.all` is used by default when neither `.all` nor `.any` are
* added earlier in the chain. However, it's often best to add `.all` anyway
* because it improves readability.
*
* See the `.keys` doc for guidance on when to use `.any` or `.all`.
*
* @name all
* @namespace BDD
* @api public
*/
Assertion.addProperty('all', function () {
flag(this, 'all', true);
flag(this, 'any', false);
});
/**
* ### .a(type[, msg])
*
* Asserts that the target's type is equal to the given string `type`. Types
* are case insensitive. See the `type-detect` project page for info on the
* type detection algorithm: https://github.com/chaijs/type-detect.
*
* expect('foo').to.be.a('string');
* expect({a: 1}).to.be.an('object');
* expect(null).to.be.a('null');
* expect(undefined).to.be.an('undefined');
* expect(new Error).to.be.an('error');
* expect(Promise.resolve()).to.be.a('promise');
* expect(new Float32Array).to.be.a('float32array');
* expect(Symbol()).to.be.a('symbol');
*
* `.a` supports objects that have a custom type set via `Symbol.toStringTag`.
*
* var myObj = {
* [Symbol.toStringTag]: 'myCustomType'
* };
*
* expect(myObj).to.be.a('myCustomType').but.not.an('object');
*
* It's often best to use `.a` to check a target's type before making more
* assertions on the same target. That way, you avoid unexpected behavior from
* any assertion that does different things based on the target's type.
*
* expect([1, 2, 3]).to.be.an('array').that.includes(2);
* expect([]).to.be.an('array').that.is.empty;
*
* Add `.not` earlier in the chain to negate `.a`. However, it's often best to
* assert that the target is the expected type, rather than asserting that it
* isn't one of many unexpected types.
*
* expect('foo').to.be.a('string'); // Recommended
* expect('foo').to.not.be.an('array'); // Not recommended
*
* `.a` accepts an optional `msg` argument which is a custom error message to
* show when the assertion fails. The message can also be given as the second
* argument to `expect`.
*
* expect(1).to.be.a('string', 'nooo why fail??');
* expect(1, 'nooo why fail??').to.be.a('string');
*
* `.a` can also be used as a language chain to improve the readability of
* your assertions.
*
* expect({b: 2}).to.have.a.property('b');
*
* The alias `.an` can be used interchangeably with `.a`.
*
* @name a
* @alias an
* @param {String} type
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function an (type, msg) {
if (msg) flag(this, 'message', msg);
type = type.toLowerCase();
var obj = flag(this, 'object')
, article = ~[ 'a', 'e', 'i', 'o', 'u' ].indexOf(type.charAt(0)) ? 'an ' : 'a ';
this.assert(
type === _.type(obj).toLowerCase()
, 'expected #{this} to be ' + article + type
, 'expected #{this} not to be ' + article + type
);
}
Assertion.addChainableMethod('an', an);
Assertion.addChainableMethod('a', an);
/**
* ### .include(val[, msg])
*
* When the target is a string, `.include` asserts that the given string `val`
* is a substring of the target.
*
* expect('foobar').to.include('foo');
*
* When the target is an array, `.include` asserts that the given `val` is a
* member of the target.
*
* expect([1, 2, 3]).to.include(2);
*
* When the target is an object, `.include` asserts that the given object
* `val`'s properties are a subset of the target's properties.
*
* expect({a: 1, b: 2, c: 3}).to.include({a: 1, b: 2});
*
* When the target is a Set or WeakSet, `.include` asserts that the given `val` is a
* member of the target. SameValueZero equality algorithm is used.
*
* expect(new Set([1, 2])).to.include(2);
*
* When the target is a Map, `.include` asserts that the given `val` is one of
* the values of the target. SameValueZero equality algorithm is used.
*
* expect(new Map([['a', 1], ['b', 2]])).to.include(2);
*
* Because `.include` does different things based on the target's type, it's
* important to check the target's type before using `.include`. See the `.a`
* doc for info on testing a target's type.
*
* expect([1, 2, 3]).to.be.an('array').that.includes(2);
*
* By default, strict (`===`) equality is used to compare array members and
* object properties. Add `.deep` earlier in the chain to use deep equality
* instead (WeakSet targets are not supported). See the `deep-eql` project
* page for info on the deep equality algorithm: https://github.com/chaijs/deep-eql.
*
* // Target array deeply (but not strictly) includes `{a: 1}`
* expect([{a: 1}]).to.deep.include({a: 1});
* expect([{a: 1}]).to.not.include({a: 1});
*
* // Target object deeply (but not strictly) includes `x: {a: 1}`
* expect({x: {a: 1}}).to.deep.include({x: {a: 1}});
* expect({x: {a: 1}}).to.not.include({x: {a: 1}});
*
* By default, all of the target's properties are searched when working with
* objects. This includes properties that are inherited and/or non-enumerable.
* Add `.own` earlier in the chain to exclude the target's inherited
* properties from the search.
*
* Object.prototype.b = 2;
*
* expect({a: 1}).to.own.include({a: 1});
* expect({a: 1}).to.include({b: 2}).but.not.own.include({b: 2});
*
* Note that a target object is always only searched for `val`'s own
* enumerable properties.
*
* `.deep` and `.own` can be combined.
*
* expect({a: {b: 2}}).to.deep.own.include({a: {b: 2}});
*
* Add `.nested` earlier in the chain to enable dot- and bracket-notation when
* referencing nested properties.
*
* expect({a: {b: ['x', 'y']}}).to.nested.include({'a.b[1]': 'y'});
*
* If `.` or `[]` are part of an actual property name, they can be escaped by
* adding two backslashes before them.
*
* expect({'.a': {'[b]': 2}}).to.nested.include({'\\.a.\\[b\\]': 2});
*
* `.deep` and `.nested` can be combined.
*
* expect({a: {b: [{c: 3}]}}).to.deep.nested.include({'a.b[0]': {c: 3}});
*
* `.own` and `.nested` cannot be combined.
*
* Add `.not` earlier in the chain to negate `.include`.
*
* expect('foobar').to.not.include('taco');
* expect([1, 2, 3]).to.not.include(4);
*
* However, it's dangerous to negate `.include` when the target is an object.
* The problem is that it creates uncertain expectations by asserting that the
* target object doesn't have all of `val`'s key/value pairs but may or may
* not have some of them. It's often best to identify the exact output that's
* expected, and then write an assertion that only accepts that exact output.
*
* When the target object isn't even expected to have `val`'s keys, it's
* often best to assert exactly that.
*
* expect({c: 3}).to.not.have.any.keys('a', 'b'); // Recommended
* expect({c: 3}).to.not.include({a: 1, b: 2}); // Not recommended
*
* When the target object is expected to have `val`'s keys, it's often best to
* assert that each of the properties has its expected value, rather than
* asserting that each property doesn't have one of many unexpected values.
*
* expect({a: 3, b: 4}).to.include({a: 3, b: 4}); // Recommended
* expect({a: 3, b: 4}).to.not.include({a: 1, b: 2}); // Not recommended
*
* `.include` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`.
*
* expect([1, 2, 3]).to.include(4, 'nooo why fail??');
* expect([1, 2, 3], 'nooo why fail??').to.include(4);
*
* `.include` can also be used as a language chain, causing all `.members` and
* `.keys` assertions that follow in the chain to require the target to be a
* superset of the expected set, rather than an identical set. Note that
* `.members` ignores duplicates in the subset when `.include` is added.
*
* // Target object's keys are a superset of ['a', 'b'] but not identical
* expect({a: 1, b: 2, c: 3}).to.include.all.keys('a', 'b');
* expect({a: 1, b: 2, c: 3}).to.not.have.all.keys('a', 'b');
*
* // Target array is a superset of [1, 2] but not identical
* expect([1, 2, 3]).to.include.members([1, 2]);
* expect([1, 2, 3]).to.not.have.members([1, 2]);
*
* // Duplicates in the subset are ignored
* expect([1, 2, 3]).to.include.members([1, 2, 2, 2]);
*
* Note that adding `.any` earlier in the chain causes the `.keys` assertion
* to ignore `.include`.
*
* // Both assertions are identical
* expect({a: 1}).to.include.any.keys('a', 'b');
* expect({a: 1}).to.have.any.keys('a', 'b');
*
* The aliases `.includes`, `.contain`, and `.contains` can be used
* interchangeably with `.include`.
*
* @name include
* @alias contain
* @alias includes
* @alias contains
* @param {Mixed} val
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function SameValueZero(a, b) {
return (_.isNaN(a) && _.isNaN(b)) || a === b;
}
function includeChainingBehavior () {
flag(this, 'contains', true);
}
function include (val, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, objType = _.type(obj).toLowerCase()
, flagMsg = flag(this, 'message')
, negate = flag(this, 'negate')
, ssfi = flag(this, 'ssfi')
, isDeep = flag(this, 'deep')
, descriptor = isDeep ? 'deep ' : '';
flagMsg = flagMsg ? flagMsg + ': ' : '';
var included = false;
switch (objType) {
case 'string':
included = obj.indexOf(val) !== -1;
break;
case 'weakset':
if (isDeep) {
throw new AssertionError(
flagMsg + 'unable to use .deep.include with WeakSet',
undefined,
ssfi
);
}
included = obj.has(val);
break;
case 'map':
var isEql = isDeep ? _.eql : SameValueZero;
obj.forEach(function (item) {
included = included || isEql(item, val);
});
break;
case 'set':
if (isDeep) {
obj.forEach(function (item) {
included = included || _.eql(item, val);
});
} else {
included = obj.has(val);
}
break;
case 'array':
if (isDeep) {
included = obj.some(function (item) {
return _.eql(item, val);
})
} else {
included = obj.indexOf(val) !== -1;
}
break;
default:
// This block is for asserting a subset of properties in an object.
// `_.expectTypes` isn't used here because `.include` should work with
// objects with a custom `@@toStringTag`.
if (val !== Object(val)) {
throw new AssertionError(
flagMsg + 'object tested must be an array, a map, an object,'
+ ' a set, a string, or a weakset, but ' + objType + ' given',
undefined,
ssfi
);
}
var props = Object.keys(val)
, firstErr = null
, numErrs = 0;
props.forEach(function (prop) {
var propAssertion = new Assertion(obj);
_.transferFlags(this, propAssertion, true);
flag(propAssertion, 'lockSsfi', true);
if (!negate || props.length === 1) {
propAssertion.property(prop, val[prop]);
return;
}
try {
propAssertion.property(prop, val[prop]);
} catch (err) {
if (!_.checkError.compatibleConstructor(err, AssertionError)) {
throw err;
}
if (firstErr === null) firstErr = err;
numErrs++;
}
}, this);
// When validating .not.include with multiple properties, we only want
// to throw an assertion error if all of the properties are included,
// in which case we throw the first property assertion error that we
// encountered.
if (negate && props.length > 1 && numErrs === props.length) {
throw firstErr;
}
return;
}
// Assert inclusion in collection or substring in a string.
this.assert(
included
, 'expected #{this} to ' + descriptor + 'include ' + _.inspect(val)
, 'expected #{this} to not ' + descriptor + 'include ' + _.inspect(val));
}
Assertion.addChainableMethod('include', include, includeChainingBehavior);
Assertion.addChainableMethod('contain', include, includeChainingBehavior);
Assertion.addChainableMethod('contains', include, includeChainingBehavior);
Assertion.addChainableMethod('includes', include, includeChainingBehavior);
/**
* ### .ok
*
* Asserts that the target is a truthy value (considered `true` in boolean context).
* However, it's often best to assert that the target is strictly (`===`) or
* deeply equal to its expected value.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.be.ok; // Not recommended
*
* expect(true).to.be.true; // Recommended
* expect(true).to.be.ok; // Not recommended
*
* Add `.not` earlier in the chain to negate `.ok`.
*
* expect(0).to.equal(0); // Recommended
* expect(0).to.not.be.ok; // Not recommended
*
* expect(false).to.be.false; // Recommended
* expect(false).to.not.be.ok; // Not recommended
*
* expect(null).to.be.null; // Recommended
* expect(null).to.not.be.ok; // Not recommended
*
* expect(undefined).to.be.undefined; // Recommended
* expect(undefined).to.not.be.ok; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect(false, 'nooo why fail??').to.be.ok;
*
* @name ok
* @namespace BDD
* @api public
*/
Assertion.addProperty('ok', function () {
this.assert(
flag(this, 'object')
, 'expected #{this} to be truthy'
, 'expected #{this} to be falsy');
});
/**
* ### .true
*
* Asserts that the target is strictly (`===`) equal to `true`.
*
* expect(true).to.be.true;
*
* Add `.not` earlier in the chain to negate `.true`. However, it's often best
* to assert that the target is equal to its expected value, rather than not
* equal to `true`.
*
* expect(false).to.be.false; // Recommended
* expect(false).to.not.be.true; // Not recommended
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.not.be.true; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect(false, 'nooo why fail??').to.be.true;
*
* @name true
* @namespace BDD
* @api public
*/
Assertion.addProperty('true', function () {
this.assert(
true === flag(this, 'object')
, 'expected #{this} to be true'
, 'expected #{this} to be false'
, flag(this, 'negate') ? false : true
);
});
/**
* ### .false
*
* Asserts that the target is strictly (`===`) equal to `false`.
*
* expect(false).to.be.false;
*
* Add `.not` earlier in the chain to negate `.false`. However, it's often
* best to assert that the target is equal to its expected value, rather than
* not equal to `false`.
*
* expect(true).to.be.true; // Recommended
* expect(true).to.not.be.false; // Not recommended
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.not.be.false; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect(true, 'nooo why fail??').to.be.false;
*
* @name false
* @namespace BDD
* @api public
*/
Assertion.addProperty('false', function () {
this.assert(
false === flag(this, 'object')
, 'expected #{this} to be false'
, 'expected #{this} to be true'
, flag(this, 'negate') ? true : false
);
});
/**
* ### .null
*
* Asserts that the target is strictly (`===`) equal to `null`.
*
* expect(null).to.be.null;
*
* Add `.not` earlier in the chain to negate `.null`. However, it's often best
* to assert that the target is equal to its expected value, rather than not
* equal to `null`.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.not.be.null; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect(42, 'nooo why fail??').to.be.null;
*
* @name null
* @namespace BDD
* @api public
*/
Assertion.addProperty('null', function () {
this.assert(
null === flag(this, 'object')
, 'expected #{this} to be null'
, 'expected #{this} not to be null'
);
});
/**
* ### .undefined
*
* Asserts that the target is strictly (`===`) equal to `undefined`.
*
* expect(undefined).to.be.undefined;
*
* Add `.not` earlier in the chain to negate `.undefined`. However, it's often
* best to assert that the target is equal to its expected value, rather than
* not equal to `undefined`.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.not.be.undefined; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect(42, 'nooo why fail??').to.be.undefined;
*
* @name undefined
* @namespace BDD
* @api public
*/
Assertion.addProperty('undefined', function () {
this.assert(
undefined === flag(this, 'object')
, 'expected #{this} to be undefined'
, 'expected #{this} not to be undefined'
);
});
/**
* ### .NaN
*
* Asserts that the target is exactly `NaN`.
*
* expect(NaN).to.be.NaN;
*
* Add `.not` earlier in the chain to negate `.NaN`. However, it's often best
* to assert that the target is equal to its expected value, rather than not
* equal to `NaN`.
*
* expect('foo').to.equal('foo'); // Recommended
* expect('foo').to.not.be.NaN; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect(42, 'nooo why fail??').to.be.NaN;
*
* @name NaN
* @namespace BDD
* @api public
*/
Assertion.addProperty('NaN', function () {
this.assert(
_.isNaN(flag(this, 'object'))
, 'expected #{this} to be NaN'
, 'expected #{this} not to be NaN'
);
});
/**
* ### .exist
*
* Asserts that the target is not strictly (`===`) equal to either `null` or
* `undefined`. However, it's often best to assert that the target is equal to
* its expected value.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.exist; // Not recommended
*
* expect(0).to.equal(0); // Recommended
* expect(0).to.exist; // Not recommended
*
* Add `.not` earlier in the chain to negate `.exist`.
*
* expect(null).to.be.null; // Recommended
* expect(null).to.not.exist; // Not recommended
*
* expect(undefined).to.be.undefined; // Recommended
* expect(undefined).to.not.exist; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect(null, 'nooo why fail??').to.exist;
*
* @name exist
* @namespace BDD
* @api public
*/
Assertion.addProperty('exist', function () {
var val = flag(this, 'object');
this.assert(
val !== null && val !== undefined
, 'expected #{this} to exist'
, 'expected #{this} to not exist'
);
});
/**
* ### .empty
*
* When the target is a string or array, `.empty` asserts that the target's
* `length` property is strictly (`===`) equal to `0`.
*
* expect([]).to.be.empty;
* expect('').to.be.empty;
*
* When the target is a map or set, `.empty` asserts that the target's `size`
* property is strictly equal to `0`.
*
* expect(new Set()).to.be.empty;
* expect(new Map()).to.be.empty;
*
* When the target is a non-function object, `.empty` asserts that the target
* doesn't have any own enumerable properties. Properties with Symbol-based
* keys are excluded from the count.
*
* expect({}).to.be.empty;
*
* Because `.empty` does different things based on the target's type, it's
* important to check the target's type before using `.empty`. See the `.a`
* doc for info on testing a target's type.
*
* expect([]).to.be.an('array').that.is.empty;
*
* Add `.not` earlier in the chain to negate `.empty`. However, it's often
* best to assert that the target contains its expected number of values,
* rather than asserting that it's not empty.
*
* expect([1, 2, 3]).to.have.lengthOf(3); // Recommended
* expect([1, 2, 3]).to.not.be.empty; // Not recommended
*
* expect(new Set([1, 2, 3])).to.have.property('size', 3); // Recommended
* expect(new Set([1, 2, 3])).to.not.be.empty; // Not recommended
*
* expect(Object.keys({a: 1})).to.have.lengthOf(1); // Recommended
* expect({a: 1}).to.not.be.empty; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect([1, 2, 3], 'nooo why fail??').to.be.empty;
*
* @name empty
* @namespace BDD
* @api public
*/
Assertion.addProperty('empty', function () {
var val = flag(this, 'object')
, ssfi = flag(this, 'ssfi')
, flagMsg = flag(this, 'message')
, itemsCount;
flagMsg = flagMsg ? flagMsg + ': ' : '';
switch (_.type(val).toLowerCase()) {
case 'array':
case 'string':
itemsCount = val.length;
break;
case 'map':
case 'set':
itemsCount = val.size;
break;
case 'weakmap':
case 'weakset':
throw new AssertionError(
flagMsg + '.empty was passed a weak collection',
undefined,
ssfi
);
case 'function':
var msg = flagMsg + '.empty was passed a function ' + _.getName(val);
throw new AssertionError(msg.trim(), undefined, ssfi);
default:
if (val !== Object(val)) {
throw new AssertionError(
flagMsg + '.empty was passed non-string primitive ' + _.inspect(val),
undefined,
ssfi
);
}
itemsCount = Object.keys(val).length;
}
this.assert(
0 === itemsCount
, 'expected #{this} to be empty'
, 'expected #{this} not to be empty'
);
});
/**
* ### .arguments
*
* Asserts that the target is an `arguments` object.
*
* function test () {
* expect(arguments).to.be.arguments;
* }
*
* test();
*
* Add `.not` earlier in the chain to negate `.arguments`. However, it's often
* best to assert which type the target is expected to be, rather than
* asserting that its not an `arguments` object.
*
* expect('foo').to.be.a('string'); // Recommended
* expect('foo').to.not.be.arguments; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect({}, 'nooo why fail??').to.be.arguments;
*
* The alias `.Arguments` can be used interchangeably with `.arguments`.
*
* @name arguments
* @alias Arguments
* @namespace BDD
* @api public
*/
function checkArguments () {
var obj = flag(this, 'object')
, type = _.type(obj);
this.assert(
'Arguments' === type
, 'expected #{this} to be arguments but got ' + type
, 'expected #{this} to not be arguments'
);
}
Assertion.addProperty('arguments', checkArguments);
Assertion.addProperty('Arguments', checkArguments);
/**
* ### .equal(val[, msg])
*
* Asserts that the target is strictly (`===`) equal to the given `val`.
*
* expect(1).to.equal(1);
* expect('foo').to.equal('foo');
*
* Add `.deep` earlier in the chain to use deep equality instead. See the
* `deep-eql` project page for info on the deep equality algorithm:
* https://github.com/chaijs/deep-eql.
*
* // Target object deeply (but not strictly) equals `{a: 1}`
* expect({a: 1}).to.deep.equal({a: 1});
* expect({a: 1}).to.not.equal({a: 1});
*
* // Target array deeply (but not strictly) equals `[1, 2]`
* expect([1, 2]).to.deep.equal([1, 2]);
* expect([1, 2]).to.not.equal([1, 2]);
*
* Add `.not` earlier in the chain to negate `.equal`. However, it's often
* best to assert that the target is equal to its expected value, rather than
* not equal to one of countless unexpected values.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.not.equal(2); // Not recommended
*
* `.equal` accepts an optional `msg` argument which is a custom error message
* to show when the assertion fails. The message can also be given as the
* second argument to `expect`.
*
* expect(1).to.equal(2, 'nooo why fail??');
* expect(1, 'nooo why fail??').to.equal(2);
*
* The aliases `.equals` and `eq` can be used interchangeably with `.equal`.
*
* @name equal
* @alias equals
* @alias eq
* @param {Mixed} val
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertEqual (val, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object');
if (flag(this, 'deep')) {
var prevLockSsfi = flag(this, 'lockSsfi');
flag(this, 'lockSsfi', true);
this.eql(val);
flag(this, 'lockSsfi', prevLockSsfi);
} else {
this.assert(
val === obj
, 'expected #{this} to equal #{exp}'
, 'expected #{this} to not equal #{exp}'
, val
, this._obj
, true
);
}
}
Assertion.addMethod('equal', assertEqual);
Assertion.addMethod('equals', assertEqual);
Assertion.addMethod('eq', assertEqual);
/**
* ### .eql(obj[, msg])
*
* Asserts that the target is deeply equal to the given `obj`. See the
* `deep-eql` project page for info on the deep equality algorithm:
* https://github.com/chaijs/deep-eql.
*
* // Target object is deeply (but not strictly) equal to {a: 1}
* expect({a: 1}).to.eql({a: 1}).but.not.equal({a: 1});
*
* // Target array is deeply (but not strictly) equal to [1, 2]
* expect([1, 2]).to.eql([1, 2]).but.not.equal([1, 2]);
*
* Add `.not` earlier in the chain to negate `.eql`. However, it's often best
* to assert that the target is deeply equal to its expected value, rather
* than not deeply equal to one of countless unexpected values.
*
* expect({a: 1}).to.eql({a: 1}); // Recommended
* expect({a: 1}).to.not.eql({b: 2}); // Not recommended
*
* `.eql` accepts an optional `msg` argument which is a custom error message
* to show when the assertion fails. The message can also be given as the
* second argument to `expect`.
*
* expect({a: 1}).to.eql({b: 2}, 'nooo why fail??');
* expect({a: 1}, 'nooo why fail??').to.eql({b: 2});
*
* The alias `.eqls` can be used interchangeably with `.eql`.
*
* The `.deep.equal` assertion is almost identical to `.eql` but with one
* difference: `.deep.equal` causes deep equality comparisons to also be used
* for any other assertions that follow in the chain.
*
* @name eql
* @alias eqls
* @param {Mixed} obj
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertEql(obj, msg) {
if (msg) flag(this, 'message', msg);
this.assert(
_.eql(obj, flag(this, 'object'))
, 'expected #{this} to deeply equal #{exp}'
, 'expected #{this} to not deeply equal #{exp}'
, obj
, this._obj
, true
);
}
Assertion.addMethod('eql', assertEql);
Assertion.addMethod('eqls', assertEql);
/**
* ### .above(n[, msg])
*
* Asserts that the target is a number or a date greater than the given number or date `n` respectively.
* However, it's often best to assert that the target is equal to its expected
* value.
*
* expect(2).to.equal(2); // Recommended
* expect(2).to.be.above(1); // Not recommended
*
* Add `.lengthOf` earlier in the chain to assert that the target's `length`
* or `size` is greater than the given number `n`.
*
* expect('foo').to.have.lengthOf(3); // Recommended
* expect('foo').to.have.lengthOf.above(2); // Not recommended
*
* expect([1, 2, 3]).to.have.lengthOf(3); // Recommended
* expect([1, 2, 3]).to.have.lengthOf.above(2); // Not recommended
*
* Add `.not` earlier in the chain to negate `.above`.
*
* expect(2).to.equal(2); // Recommended
* expect(1).to.not.be.above(2); // Not recommended
*
* `.above` accepts an optional `msg` argument which is a custom error message
* to show when the assertion fails. The message can also be given as the
* second argument to `expect`.
*
* expect(1).to.be.above(2, 'nooo why fail??');
* expect(1, 'nooo why fail??').to.be.above(2);
*
* The aliases `.gt` and `.greaterThan` can be used interchangeably with
* `.above`.
*
* @name above
* @alias gt
* @alias greaterThan
* @param {Number} n
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertAbove (n, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, doLength = flag(this, 'doLength')
, flagMsg = flag(this, 'message')
, msgPrefix = ((flagMsg) ? flagMsg + ': ' : '')
, ssfi = flag(this, 'ssfi')
, objType = _.type(obj).toLowerCase()
, nType = _.type(n).toLowerCase()
, errorMessage
, shouldThrow = true;
if (doLength && objType !== 'map' && objType !== 'set') {
new Assertion(obj, flagMsg, ssfi, true).to.have.property('length');
}
if (!doLength && (objType === 'date' && nType !== 'date')) {
errorMessage = msgPrefix + 'the argument to above must be a date';
} else if (nType !== 'number' && (doLength || objType === 'number')) {
errorMessage = msgPrefix + 'the argument to above must be a number';
} else if (!doLength && (objType !== 'date' && objType !== 'number')) {
var printObj = (objType === 'string') ? "'" + obj + "'" : obj;
errorMessage = msgPrefix + 'expected ' + printObj + ' to be a number or a date';
} else {
shouldThrow = false;
}
if (shouldThrow) {
throw new AssertionError(errorMessage, undefined, ssfi);
}
if (doLength) {
var descriptor = 'length'
, itemsCount;
if (objType === 'map' || objType === 'set') {
descriptor = 'size';
itemsCount = obj.size;
} else {
itemsCount = obj.length;
}
this.assert(
itemsCount > n
, 'expected #{this} to have a ' + descriptor + ' above #{exp} but got #{act}'
, 'expected #{this} to not have a ' + descriptor + ' above #{exp}'
, n
, itemsCount
);
} else {
this.assert(
obj > n
, 'expected #{this} to be above #{exp}'
, 'expected #{this} to be at most #{exp}'
, n
);
}
}
Assertion.addMethod('above', assertAbove);
Assertion.addMethod('gt', assertAbove);
Assertion.addMethod('greaterThan', assertAbove);
/**
* ### .least(n[, msg])
*
* Asserts that the target is a number or a date greater than or equal to the given
* number or date `n` respectively. However, it's often best to assert that the target is equal to
* its expected value.
*
* expect(2).to.equal(2); // Recommended
* expect(2).to.be.at.least(1); // Not recommended
* expect(2).to.be.at.least(2); // Not recommended
*
* Add `.lengthOf` earlier in the chain to assert that the target's `length`
* or `size` is greater than or equal to the given number `n`.
*
* expect('foo').to.have.lengthOf(3); // Recommended
* expect('foo').to.have.lengthOf.at.least(2); // Not recommended
*
* expect([1, 2, 3]).to.have.lengthOf(3); // Recommended
* expect([1, 2, 3]).to.have.lengthOf.at.least(2); // Not recommended
*
* Add `.not` earlier in the chain to negate `.least`.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.not.be.at.least(2); // Not recommended
*
* `.least` accepts an optional `msg` argument which is a custom error message
* to show when the assertion fails. The message can also be given as the
* second argument to `expect`.
*
* expect(1).to.be.at.least(2, 'nooo why fail??');
* expect(1, 'nooo why fail??').to.be.at.least(2);
*
* The alias `.gte` can be used interchangeably with `.least`.
*
* @name least
* @alias gte
* @param {Number} n
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertLeast (n, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, doLength = flag(this, 'doLength')
, flagMsg = flag(this, 'message')
, msgPrefix = ((flagMsg) ? flagMsg + ': ' : '')
, ssfi = flag(this, 'ssfi')
, objType = _.type(obj).toLowerCase()
, nType = _.type(n).toLowerCase()
, errorMessage
, shouldThrow = true;
if (doLength && objType !== 'map' && objType !== 'set') {
new Assertion(obj, flagMsg, ssfi, true).to.have.property('length');
}
if (!doLength && (objType === 'date' && nType !== 'date')) {
errorMessage = msgPrefix + 'the argument to least must be a date';
} else if (nType !== 'number' && (doLength || objType === 'number')) {
errorMessage = msgPrefix + 'the argument to least must be a number';
} else if (!doLength && (objType !== 'date' && objType !== 'number')) {
var printObj = (objType === 'string') ? "'" + obj + "'" : obj;
errorMessage = msgPrefix + 'expected ' + printObj + ' to be a number or a date';
} else {
shouldThrow = false;
}
if (shouldThrow) {
throw new AssertionError(errorMessage, undefined, ssfi);
}
if (doLength) {
var descriptor = 'length'
, itemsCount;
if (objType === 'map' || objType === 'set') {
descriptor = 'size';
itemsCount = obj.size;
} else {
itemsCount = obj.length;
}
this.assert(
itemsCount >= n
, 'expected #{this} to have a ' + descriptor + ' at least #{exp} but got #{act}'
, 'expected #{this} to have a ' + descriptor + ' below #{exp}'
, n
, itemsCount
);
} else {
this.assert(
obj >= n
, 'expected #{this} to be at least #{exp}'
, 'expected #{this} to be below #{exp}'
, n
);
}
}
Assertion.addMethod('least', assertLeast);
Assertion.addMethod('gte', assertLeast);
/**
* ### .below(n[, msg])
*
* Asserts that the target is a number or a date less than the given number or date `n` respectively.
* However, it's often best to assert that the target is equal to its expected
* value.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.be.below(2); // Not recommended
*
* Add `.lengthOf` earlier in the chain to assert that the target's `length`
* or `size` is less than the given number `n`.
*
* expect('foo').to.have.lengthOf(3); // Recommended
* expect('foo').to.have.lengthOf.below(4); // Not recommended
*
* expect([1, 2, 3]).to.have.length(3); // Recommended
* expect([1, 2, 3]).to.have.lengthOf.below(4); // Not recommended
*
* Add `.not` earlier in the chain to negate `.below`.
*
* expect(2).to.equal(2); // Recommended
* expect(2).to.not.be.below(1); // Not recommended
*
* `.below` accepts an optional `msg` argument which is a custom error message
* to show when the assertion fails. The message can also be given as the
* second argument to `expect`.
*
* expect(2).to.be.below(1, 'nooo why fail??');
* expect(2, 'nooo why fail??').to.be.below(1);
*
* The aliases `.lt` and `.lessThan` can be used interchangeably with
* `.below`.
*
* @name below
* @alias lt
* @alias lessThan
* @param {Number} n
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertBelow (n, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, doLength = flag(this, 'doLength')
, flagMsg = flag(this, 'message')
, msgPrefix = ((flagMsg) ? flagMsg + ': ' : '')
, ssfi = flag(this, 'ssfi')
, objType = _.type(obj).toLowerCase()
, nType = _.type(n).toLowerCase()
, errorMessage
, shouldThrow = true;
if (doLength && objType !== 'map' && objType !== 'set') {
new Assertion(obj, flagMsg, ssfi, true).to.have.property('length');
}
if (!doLength && (objType === 'date' && nType !== 'date')) {
errorMessage = msgPrefix + 'the argument to below must be a date';
} else if (nType !== 'number' && (doLength || objType === 'number')) {
errorMessage = msgPrefix + 'the argument to below must be a number';
} else if (!doLength && (objType !== 'date' && objType !== 'number')) {
var printObj = (objType === 'string') ? "'" + obj + "'" : obj;
errorMessage = msgPrefix + 'expected ' + printObj + ' to be a number or a date';
} else {
shouldThrow = false;
}
if (shouldThrow) {
throw new AssertionError(errorMessage, undefined, ssfi);
}
if (doLength) {
var descriptor = 'length'
, itemsCount;
if (objType === 'map' || objType === 'set') {
descriptor = 'size';
itemsCount = obj.size;
} else {
itemsCount = obj.length;
}
this.assert(
itemsCount < n
, 'expected #{this} to have a ' + descriptor + ' below #{exp} but got #{act}'
, 'expected #{this} to not have a ' + descriptor + ' below #{exp}'
, n
, itemsCount
);
} else {
this.assert(
obj < n
, 'expected #{this} to be below #{exp}'
, 'expected #{this} to be at least #{exp}'
, n
);
}
}
Assertion.addMethod('below', assertBelow);
Assertion.addMethod('lt', assertBelow);
Assertion.addMethod('lessThan', assertBelow);
/**
* ### .most(n[, msg])
*
* Asserts that the target is a number or a date less than or equal to the given number
* or date `n` respectively. However, it's often best to assert that the target is equal to its
* expected value.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.be.at.most(2); // Not recommended
* expect(1).to.be.at.most(1); // Not recommended
*
* Add `.lengthOf` earlier in the chain to assert that the target's `length`
* or `size` is less than or equal to the given number `n`.
*
* expect('foo').to.have.lengthOf(3); // Recommended
* expect('foo').to.have.lengthOf.at.most(4); // Not recommended
*
* expect([1, 2, 3]).to.have.lengthOf(3); // Recommended
* expect([1, 2, 3]).to.have.lengthOf.at.most(4); // Not recommended
*
* Add `.not` earlier in the chain to negate `.most`.
*
* expect(2).to.equal(2); // Recommended
* expect(2).to.not.be.at.most(1); // Not recommended
*
* `.most` accepts an optional `msg` argument which is a custom error message
* to show when the assertion fails. The message can also be given as the
* second argument to `expect`.
*
* expect(2).to.be.at.most(1, 'nooo why fail??');
* expect(2, 'nooo why fail??').to.be.at.most(1);
*
* The alias `.lte` can be used interchangeably with `.most`.
*
* @name most
* @alias lte
* @param {Number} n
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertMost (n, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, doLength = flag(this, 'doLength')
, flagMsg = flag(this, 'message')
, msgPrefix = ((flagMsg) ? flagMsg + ': ' : '')
, ssfi = flag(this, 'ssfi')
, objType = _.type(obj).toLowerCase()
, nType = _.type(n).toLowerCase()
, errorMessage
, shouldThrow = true;
if (doLength && objType !== 'map' && objType !== 'set') {
new Assertion(obj, flagMsg, ssfi, true).to.have.property('length');
}
if (!doLength && (objType === 'date' && nType !== 'date')) {
errorMessage = msgPrefix + 'the argument to most must be a date';
} else if (nType !== 'number' && (doLength || objType === 'number')) {
errorMessage = msgPrefix + 'the argument to most must be a number';
} else if (!doLength && (objType !== 'date' && objType !== 'number')) {
var printObj = (objType === 'string') ? "'" + obj + "'" : obj;
errorMessage = msgPrefix + 'expected ' + printObj + ' to be a number or a date';
} else {
shouldThrow = false;
}
if (shouldThrow) {
throw new AssertionError(errorMessage, undefined, ssfi);
}
if (doLength) {
var descriptor = 'length'
, itemsCount;
if (objType === 'map' || objType === 'set') {
descriptor = 'size';
itemsCount = obj.size;
} else {
itemsCount = obj.length;
}
this.assert(
itemsCount <= n
, 'expected #{this} to have a ' + descriptor + ' at most #{exp} but got #{act}'
, 'expected #{this} to have a ' + descriptor + ' above #{exp}'
, n
, itemsCount
);
} else {
this.assert(
obj <= n
, 'expected #{this} to be at most #{exp}'
, 'expected #{this} to be above #{exp}'
, n
);
}
}
Assertion.addMethod('most', assertMost);
Assertion.addMethod('lte', assertMost);
/**
* ### .within(start, finish[, msg])
*
* Asserts that the target is a number or a date greater than or equal to the given
* number or date `start`, and less than or equal to the given number or date `finish` respectively.
* However, it's often best to assert that the target is equal to its expected
* value.
*
* expect(2).to.equal(2); // Recommended
* expect(2).to.be.within(1, 3); // Not recommended
* expect(2).to.be.within(2, 3); // Not recommended
* expect(2).to.be.within(1, 2); // Not recommended
*
* Add `.lengthOf` earlier in the chain to assert that the target's `length`
* or `size` is greater than or equal to the given number `start`, and less
* than or equal to the given number `finish`.
*
* expect('foo').to.have.lengthOf(3); // Recommended
* expect('foo').to.have.lengthOf.within(2, 4); // Not recommended
*
* expect([1, 2, 3]).to.have.lengthOf(3); // Recommended
* expect([1, 2, 3]).to.have.lengthOf.within(2, 4); // Not recommended
*
* Add `.not` earlier in the chain to negate `.within`.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.not.be.within(2, 4); // Not recommended
*
* `.within` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`.
*
* expect(4).to.be.within(1, 3, 'nooo why fail??');
* expect(4, 'nooo why fail??').to.be.within(1, 3);
*
* @name within
* @param {Number} start lower bound inclusive
* @param {Number} finish upper bound inclusive
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
Assertion.addMethod('within', function (start, finish, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, doLength = flag(this, 'doLength')
, flagMsg = flag(this, 'message')
, msgPrefix = ((flagMsg) ? flagMsg + ': ' : '')
, ssfi = flag(this, 'ssfi')
, objType = _.type(obj).toLowerCase()
, startType = _.type(start).toLowerCase()
, finishType = _.type(finish).toLowerCase()
, errorMessage
, shouldThrow = true
, range = (startType === 'date' && finishType === 'date')
? start.toUTCString() + '..' + finish.toUTCString()
: start + '..' + finish;
if (doLength && objType !== 'map' && objType !== 'set') {
new Assertion(obj, flagMsg, ssfi, true).to.have.property('length');
}
if (!doLength && (objType === 'date' && (startType !== 'date' || finishType !== 'date'))) {
errorMessage = msgPrefix + 'the arguments to within must be dates';
} else if ((startType !== 'number' || finishType !== 'number') && (doLength || objType === 'number')) {
errorMessage = msgPrefix + 'the arguments to within must be numbers';
} else if (!doLength && (objType !== 'date' && objType !== 'number')) {
var printObj = (objType === 'string') ? "'" + obj + "'" : obj;
errorMessage = msgPrefix + 'expected ' + printObj + ' to be a number or a date';
} else {
shouldThrow = false;
}
if (shouldThrow) {
throw new AssertionError(errorMessage, undefined, ssfi);
}
if (doLength) {
var descriptor = 'length'
, itemsCount;
if (objType === 'map' || objType === 'set') {
descriptor = 'size';
itemsCount = obj.size;
} else {
itemsCount = obj.length;
}
this.assert(
itemsCount >= start && itemsCount <= finish
, 'expected #{this} to have a ' + descriptor + ' within ' + range
, 'expected #{this} to not have a ' + descriptor + ' within ' + range
);
} else {
this.assert(
obj >= start && obj <= finish
, 'expected #{this} to be within ' + range
, 'expected #{this} to not be within ' + range
);
}
});
/**
* ### .instanceof(constructor[, msg])
*
* Asserts that the target is an instance of the given `constructor`.
*
* function Cat () { }
*
* expect(new Cat()).to.be.an.instanceof(Cat);
* expect([1, 2]).to.be.an.instanceof(Array);
*
* Add `.not` earlier in the chain to negate `.instanceof`.
*
* expect({a: 1}).to.not.be.an.instanceof(Array);
*
* `.instanceof` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`.
*
* expect(1).to.be.an.instanceof(Array, 'nooo why fail??');
* expect(1, 'nooo why fail??').to.be.an.instanceof(Array);
*
* Due to limitations in ES5, `.instanceof` may not always work as expected
* when using a transpiler such as Babel or TypeScript. In particular, it may
* produce unexpected results when subclassing built-in object such as
* `Array`, `Error`, and `Map`. See your transpiler's docs for details:
*
* - ([Babel](https://babeljs.io/docs/usage/caveats/#classes))
* - ([TypeScript](https://github.com/Microsoft/TypeScript/wiki/Breaking-Changes#extending-built-ins-like-error-array-and-map-may-no-longer-work))
*
* The alias `.instanceOf` can be used interchangeably with `.instanceof`.
*
* @name instanceof
* @param {Constructor} constructor
* @param {String} msg _optional_
* @alias instanceOf
* @namespace BDD
* @api public
*/
function assertInstanceOf (constructor, msg) {
if (msg) flag(this, 'message', msg);
var target = flag(this, 'object')
var ssfi = flag(this, 'ssfi');
var flagMsg = flag(this, 'message');
try {
var isInstanceOf = target instanceof constructor;
} catch (err) {
if (err instanceof TypeError) {
flagMsg = flagMsg ? flagMsg + ': ' : '';
throw new AssertionError(
flagMsg + 'The instanceof assertion needs a constructor but '
+ _.type(constructor) + ' was given.',
undefined,
ssfi
);
}
throw err;
}
var name = _.getName(constructor);
if (name === null) {
name = 'an unnamed constructor';
}
this.assert(
isInstanceOf
, 'expected #{this} to be an instance of ' + name
, 'expected #{this} to not be an instance of ' + name
);
};
Assertion.addMethod('instanceof', assertInstanceOf);
Assertion.addMethod('instanceOf', assertInstanceOf);
/**
* ### .property(name[, val[, msg]])
*
* Asserts that the target has a property with the given key `name`.
*
* expect({a: 1}).to.have.property('a');
*
* When `val` is provided, `.property` also asserts that the property's value
* is equal to the given `val`.
*
* expect({a: 1}).to.have.property('a', 1);
*
* By default, strict (`===`) equality is used. Add `.deep` earlier in the
* chain to use deep equality instead. See the `deep-eql` project page for
* info on the deep equality algorithm: https://github.com/chaijs/deep-eql.
*
* // Target object deeply (but not strictly) has property `x: {a: 1}`
* expect({x: {a: 1}}).to.have.deep.property('x', {a: 1});
* expect({x: {a: 1}}).to.not.have.property('x', {a: 1});
*
* The target's enumerable and non-enumerable properties are always included
* in the search. By default, both own and inherited properties are included.
* Add `.own` earlier in the chain to exclude inherited properties from the
* search.
*
* Object.prototype.b = 2;
*
* expect({a: 1}).to.have.own.property('a');
* expect({a: 1}).to.have.own.property('a', 1);
* expect({a: 1}).to.have.property('b');
* expect({a: 1}).to.not.have.own.property('b');
*
* `.deep` and `.own` can be combined.
*
* expect({x: {a: 1}}).to.have.deep.own.property('x', {a: 1});
*
* Add `.nested` earlier in the chain to enable dot- and bracket-notation when
* referencing nested properties.
*
* expect({a: {b: ['x', 'y']}}).to.have.nested.property('a.b[1]');
* expect({a: {b: ['x', 'y']}}).to.have.nested.property('a.b[1]', 'y');
*
* If `.` or `[]` are part of an actual property name, they can be escaped by
* adding two backslashes before them.
*
* expect({'.a': {'[b]': 'x'}}).to.have.nested.property('\\.a.\\[b\\]');
*
* `.deep` and `.nested` can be combined.
*
* expect({a: {b: [{c: 3}]}})
* .to.have.deep.nested.property('a.b[0]', {c: 3});
*
* `.own` and `.nested` cannot be combined.
*
* Add `.not` earlier in the chain to negate `.property`.
*
* expect({a: 1}).to.not.have.property('b');
*
* However, it's dangerous to negate `.property` when providing `val`. The
* problem is that it creates uncertain expectations by asserting that the
* target either doesn't have a property with the given key `name`, or that it
* does have a property with the given key `name` but its value isn't equal to
* the given `val`. It's often best to identify the exact output that's
* expected, and then write an assertion that only accepts that exact output.
*
* When the target isn't expected to have a property with the given key
* `name`, it's often best to assert exactly that.
*
* expect({b: 2}).to.not.have.property('a'); // Recommended
* expect({b: 2}).to.not.have.property('a', 1); // Not recommended
*
* When the target is expected to have a property with the given key `name`,
* it's often best to assert that the property has its expected value, rather
* than asserting that it doesn't have one of many unexpected values.
*
* expect({a: 3}).to.have.property('a', 3); // Recommended
* expect({a: 3}).to.not.have.property('a', 1); // Not recommended
*
* `.property` changes the target of any assertions that follow in the chain
* to be the value of the property from the original target object.
*
* expect({a: 1}).to.have.property('a').that.is.a('number');
*
* `.property` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`. When not providing `val`, only use the
* second form.
*
* // Recommended
* expect({a: 1}).to.have.property('a', 2, 'nooo why fail??');
* expect({a: 1}, 'nooo why fail??').to.have.property('a', 2);
* expect({a: 1}, 'nooo why fail??').to.have.property('b');
*
* // Not recommended
* expect({a: 1}).to.have.property('b', undefined, 'nooo why fail??');
*
* The above assertion isn't the same thing as not providing `val`. Instead,
* it's asserting that the target object has a `b` property that's equal to
* `undefined`.
*
* The assertions `.ownProperty` and `.haveOwnProperty` can be used
* interchangeably with `.own.property`.
*
* @name property
* @param {String} name
* @param {Mixed} val (optional)
* @param {String} msg _optional_
* @returns value of property for chaining
* @namespace BDD
* @api public
*/
function assertProperty (name, val, msg) {
if (msg) flag(this, 'message', msg);
var isNested = flag(this, 'nested')
, isOwn = flag(this, 'own')
, flagMsg = flag(this, 'message')
, obj = flag(this, 'object')
, ssfi = flag(this, 'ssfi')
, nameType = typeof name;
flagMsg = flagMsg ? flagMsg + ': ' : '';
if (isNested) {
if (nameType !== 'string') {
throw new AssertionError(
flagMsg + 'the argument to property must be a string when using nested syntax',
undefined,
ssfi
);
}
} else {
if (nameType !== 'string' && nameType !== 'number' && nameType !== 'symbol') {
throw new AssertionError(
flagMsg + 'the argument to property must be a string, number, or symbol',
undefined,
ssfi
);
}
}
if (isNested && isOwn) {
throw new AssertionError(
flagMsg + 'The "nested" and "own" flags cannot be combined.',
undefined,
ssfi
);
}
if (obj === null || obj === undefined) {
throw new AssertionError(
flagMsg + 'Target cannot be null or undefined.',
undefined,
ssfi
);
}
var isDeep = flag(this, 'deep')
, negate = flag(this, 'negate')
, pathInfo = isNested ? _.getPathInfo(obj, name) : null
, value = isNested ? pathInfo.value : obj[name];
var descriptor = '';
if (isDeep) descriptor += 'deep ';
if (isOwn) descriptor += 'own ';
if (isNested) descriptor += 'nested ';
descriptor += 'property ';
var hasProperty;
if (isOwn) hasProperty = Object.prototype.hasOwnProperty.call(obj, name);
else if (isNested) hasProperty = pathInfo.exists;
else hasProperty = _.hasProperty(obj, name);
// When performing a negated assertion for both name and val, merely having
// a property with the given name isn't enough to cause the assertion to
// fail. It must both have a property with the given name, and the value of
// that property must equal the given val. Therefore, skip this assertion in
// favor of the next.
if (!negate || arguments.length === 1) {
this.assert(
hasProperty
, 'expected #{this} to have ' + descriptor + _.inspect(name)
, 'expected #{this} to not have ' + descriptor + _.inspect(name));
}
if (arguments.length > 1) {
this.assert(
hasProperty && (isDeep ? _.eql(val, value) : val === value)
, 'expected #{this} to have ' + descriptor + _.inspect(name) + ' of #{exp}, but got #{act}'
, 'expected #{this} to not have ' + descriptor + _.inspect(name) + ' of #{act}'
, val
, value
);
}
flag(this, 'object', value);
}
Assertion.addMethod('property', assertProperty);
function assertOwnProperty (name, value, msg) {
flag(this, 'own', true);
assertProperty.apply(this, arguments);
}
Assertion.addMethod('ownProperty', assertOwnProperty);
Assertion.addMethod('haveOwnProperty', assertOwnProperty);
/**
* ### .ownPropertyDescriptor(name[, descriptor[, msg]])
*
* Asserts that the target has its own property descriptor with the given key
* `name`. Enumerable and non-enumerable properties are included in the
* search.
*
* expect({a: 1}).to.have.ownPropertyDescriptor('a');
*
* When `descriptor` is provided, `.ownPropertyDescriptor` also asserts that
* the property's descriptor is deeply equal to the given `descriptor`. See
* the `deep-eql` project page for info on the deep equality algorithm:
* https://github.com/chaijs/deep-eql.
*
* expect({a: 1}).to.have.ownPropertyDescriptor('a', {
* configurable: true,
* enumerable: true,
* writable: true,
* value: 1,
* });
*
* Add `.not` earlier in the chain to negate `.ownPropertyDescriptor`.
*
* expect({a: 1}).to.not.have.ownPropertyDescriptor('b');
*
* However, it's dangerous to negate `.ownPropertyDescriptor` when providing
* a `descriptor`. The problem is that it creates uncertain expectations by
* asserting that the target either doesn't have a property descriptor with
* the given key `name`, or that it does have a property descriptor with the
* given key `name` but its not deeply equal to the given `descriptor`. It's
* often best to identify the exact output that's expected, and then write an
* assertion that only accepts that exact output.
*
* When the target isn't expected to have a property descriptor with the given
* key `name`, it's often best to assert exactly that.
*
* // Recommended
* expect({b: 2}).to.not.have.ownPropertyDescriptor('a');
*
* // Not recommended
* expect({b: 2}).to.not.have.ownPropertyDescriptor('a', {
* configurable: true,
* enumerable: true,
* writable: true,
* value: 1,
* });
*
* When the target is expected to have a property descriptor with the given
* key `name`, it's often best to assert that the property has its expected
* descriptor, rather than asserting that it doesn't have one of many
* unexpected descriptors.
*
* // Recommended
* expect({a: 3}).to.have.ownPropertyDescriptor('a', {
* configurable: true,
* enumerable: true,
* writable: true,
* value: 3,
* });
*
* // Not recommended
* expect({a: 3}).to.not.have.ownPropertyDescriptor('a', {
* configurable: true,
* enumerable: true,
* writable: true,
* value: 1,
* });
*
* `.ownPropertyDescriptor` changes the target of any assertions that follow
* in the chain to be the value of the property descriptor from the original
* target object.
*
* expect({a: 1}).to.have.ownPropertyDescriptor('a')
* .that.has.property('enumerable', true);
*
* `.ownPropertyDescriptor` accepts an optional `msg` argument which is a
* custom error message to show when the assertion fails. The message can also
* be given as the second argument to `expect`. When not providing
* `descriptor`, only use the second form.
*
* // Recommended
* expect({a: 1}).to.have.ownPropertyDescriptor('a', {
* configurable: true,
* enumerable: true,
* writable: true,
* value: 2,
* }, 'nooo why fail??');
*
* // Recommended
* expect({a: 1}, 'nooo why fail??').to.have.ownPropertyDescriptor('a', {
* configurable: true,
* enumerable: true,
* writable: true,
* value: 2,
* });
*
* // Recommended
* expect({a: 1}, 'nooo why fail??').to.have.ownPropertyDescriptor('b');
*
* // Not recommended
* expect({a: 1})
* .to.have.ownPropertyDescriptor('b', undefined, 'nooo why fail??');
*
* The above assertion isn't the same thing as not providing `descriptor`.
* Instead, it's asserting that the target object has a `b` property
* descriptor that's deeply equal to `undefined`.
*
* The alias `.haveOwnPropertyDescriptor` can be used interchangeably with
* `.ownPropertyDescriptor`.
*
* @name ownPropertyDescriptor
* @alias haveOwnPropertyDescriptor
* @param {String} name
* @param {Object} descriptor _optional_
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertOwnPropertyDescriptor (name, descriptor, msg) {
if (typeof descriptor === 'string') {
msg = descriptor;
descriptor = null;
}
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object');
var actualDescriptor = Object.getOwnPropertyDescriptor(Object(obj), name);
if (actualDescriptor && descriptor) {
this.assert(
_.eql(descriptor, actualDescriptor)
, 'expected the own property descriptor for ' + _.inspect(name) + ' on #{this} to match ' + _.inspect(descriptor) + ', got ' + _.inspect(actualDescriptor)
, 'expected the own property descriptor for ' + _.inspect(name) + ' on #{this} to not match ' + _.inspect(descriptor)
, descriptor
, actualDescriptor
, true
);
} else {
this.assert(
actualDescriptor
, 'expected #{this} to have an own property descriptor for ' + _.inspect(name)
, 'expected #{this} to not have an own property descriptor for ' + _.inspect(name)
);
}
flag(this, 'object', actualDescriptor);
}
Assertion.addMethod('ownPropertyDescriptor', assertOwnPropertyDescriptor);
Assertion.addMethod('haveOwnPropertyDescriptor', assertOwnPropertyDescriptor);
/**
* ### .lengthOf(n[, msg])
*
* Asserts that the target's `length` or `size` is equal to the given number
* `n`.
*
* expect([1, 2, 3]).to.have.lengthOf(3);
* expect('foo').to.have.lengthOf(3);
* expect(new Set([1, 2, 3])).to.have.lengthOf(3);
* expect(new Map([['a', 1], ['b', 2], ['c', 3]])).to.have.lengthOf(3);
*
* Add `.not` earlier in the chain to negate `.lengthOf`. However, it's often
* best to assert that the target's `length` property is equal to its expected
* value, rather than not equal to one of many unexpected values.
*
* expect('foo').to.have.lengthOf(3); // Recommended
* expect('foo').to.not.have.lengthOf(4); // Not recommended
*
* `.lengthOf` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`.
*
* expect([1, 2, 3]).to.have.lengthOf(2, 'nooo why fail??');
* expect([1, 2, 3], 'nooo why fail??').to.have.lengthOf(2);
*
* `.lengthOf` can also be used as a language chain, causing all `.above`,
* `.below`, `.least`, `.most`, and `.within` assertions that follow in the
* chain to use the target's `length` property as the target. However, it's
* often best to assert that the target's `length` property is equal to its
* expected length, rather than asserting that its `length` property falls
* within some range of values.
*
* // Recommended
* expect([1, 2, 3]).to.have.lengthOf(3);
*
* // Not recommended
* expect([1, 2, 3]).to.have.lengthOf.above(2);
* expect([1, 2, 3]).to.have.lengthOf.below(4);
* expect([1, 2, 3]).to.have.lengthOf.at.least(3);
* expect([1, 2, 3]).to.have.lengthOf.at.most(3);
* expect([1, 2, 3]).to.have.lengthOf.within(2,4);
*
* Due to a compatibility issue, the alias `.length` can't be chained directly
* off of an uninvoked method such as `.a`. Therefore, `.length` can't be used
* interchangeably with `.lengthOf` in every situation. It's recommended to
* always use `.lengthOf` instead of `.length`.
*
* expect([1, 2, 3]).to.have.a.length(3); // incompatible; throws error
* expect([1, 2, 3]).to.have.a.lengthOf(3); // passes as expected
*
* @name lengthOf
* @alias length
* @param {Number} n
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertLengthChain () {
flag(this, 'doLength', true);
}
function assertLength (n, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, objType = _.type(obj).toLowerCase()
, flagMsg = flag(this, 'message')
, ssfi = flag(this, 'ssfi')
, descriptor = 'length'
, itemsCount;
switch (objType) {
case 'map':
case 'set':
descriptor = 'size';
itemsCount = obj.size;
break;
default:
new Assertion(obj, flagMsg, ssfi, true).to.have.property('length');
itemsCount = obj.length;
}
this.assert(
itemsCount == n
, 'expected #{this} to have a ' + descriptor + ' of #{exp} but got #{act}'
, 'expected #{this} to not have a ' + descriptor + ' of #{act}'
, n
, itemsCount
);
}
Assertion.addChainableMethod('length', assertLength, assertLengthChain);
Assertion.addChainableMethod('lengthOf', assertLength, assertLengthChain);
/**
* ### .match(re[, msg])
*
* Asserts that the target matches the given regular expression `re`.
*
* expect('foobar').to.match(/^foo/);
*
* Add `.not` earlier in the chain to negate `.match`.
*
* expect('foobar').to.not.match(/taco/);
*
* `.match` accepts an optional `msg` argument which is a custom error message
* to show when the assertion fails. The message can also be given as the
* second argument to `expect`.
*
* expect('foobar').to.match(/taco/, 'nooo why fail??');
* expect('foobar', 'nooo why fail??').to.match(/taco/);
*
* The alias `.matches` can be used interchangeably with `.match`.
*
* @name match
* @alias matches
* @param {RegExp} re
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertMatch(re, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object');
this.assert(
re.exec(obj)
, 'expected #{this} to match ' + re
, 'expected #{this} not to match ' + re
);
}
Assertion.addMethod('match', assertMatch);
Assertion.addMethod('matches', assertMatch);
/**
* ### .string(str[, msg])
*
* Asserts that the target string contains the given substring `str`.
*
* expect('foobar').to.have.string('bar');
*
* Add `.not` earlier in the chain to negate `.string`.
*
* expect('foobar').to.not.have.string('taco');
*
* `.string` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`.
*
* expect('foobar').to.have.string('taco', 'nooo why fail??');
* expect('foobar', 'nooo why fail??').to.have.string('taco');
*
* @name string
* @param {String} str
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
Assertion.addMethod('string', function (str, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, flagMsg = flag(this, 'message')
, ssfi = flag(this, 'ssfi');
new Assertion(obj, flagMsg, ssfi, true).is.a('string');
this.assert(
~obj.indexOf(str)
, 'expected #{this} to contain ' + _.inspect(str)
, 'expected #{this} to not contain ' + _.inspect(str)
);
});
/**
* ### .keys(key1[, key2[, ...]])
*
* Asserts that the target object, array, map, or set has the given keys. Only
* the target's own inherited properties are included in the search.
*
* When the target is an object or array, keys can be provided as one or more
* string arguments, a single array argument, or a single object argument. In
* the latter case, only the keys in the given object matter; the values are
* ignored.
*
* expect({a: 1, b: 2}).to.have.all.keys('a', 'b');
* expect(['x', 'y']).to.have.all.keys(0, 1);
*
* expect({a: 1, b: 2}).to.have.all.keys(['a', 'b']);
* expect(['x', 'y']).to.have.all.keys([0, 1]);
*
* expect({a: 1, b: 2}).to.have.all.keys({a: 4, b: 5}); // ignore 4 and 5
* expect(['x', 'y']).to.have.all.keys({0: 4, 1: 5}); // ignore 4 and 5
*
* When the target is a map or set, each key must be provided as a separate
* argument.
*
* expect(new Map([['a', 1], ['b', 2]])).to.have.all.keys('a', 'b');
* expect(new Set(['a', 'b'])).to.have.all.keys('a', 'b');
*
* Because `.keys` does different things based on the target's type, it's
* important to check the target's type before using `.keys`. See the `.a` doc
* for info on testing a target's type.
*
* expect({a: 1, b: 2}).to.be.an('object').that.has.all.keys('a', 'b');
*
* By default, strict (`===`) equality is used to compare keys of maps and
* sets. Add `.deep` earlier in the chain to use deep equality instead. See
* the `deep-eql` project page for info on the deep equality algorithm:
* https://github.com/chaijs/deep-eql.
*
* // Target set deeply (but not strictly) has key `{a: 1}`
* expect(new Set([{a: 1}])).to.have.all.deep.keys([{a: 1}]);
* expect(new Set([{a: 1}])).to.not.have.all.keys([{a: 1}]);
*
* By default, the target must have all of the given keys and no more. Add
* `.any` earlier in the chain to only require that the target have at least
* one of the given keys. Also, add `.not` earlier in the chain to negate
* `.keys`. It's often best to add `.any` when negating `.keys`, and to use
* `.all` when asserting `.keys` without negation.
*
* When negating `.keys`, `.any` is preferred because `.not.any.keys` asserts
* exactly what's expected of the output, whereas `.not.all.keys` creates
* uncertain expectations.
*
* // Recommended; asserts that target doesn't have any of the given keys
* expect({a: 1, b: 2}).to.not.have.any.keys('c', 'd');
*
* // Not recommended; asserts that target doesn't have all of the given
* // keys but may or may not have some of them
* expect({a: 1, b: 2}).to.not.have.all.keys('c', 'd');
*
* When asserting `.keys` without negation, `.all` is preferred because
* `.all.keys` asserts exactly what's expected of the output, whereas
* `.any.keys` creates uncertain expectations.
*
* // Recommended; asserts that target has all the given keys
* expect({a: 1, b: 2}).to.have.all.keys('a', 'b');
*
* // Not recommended; asserts that target has at least one of the given
* // keys but may or may not have more of them
* expect({a: 1, b: 2}).to.have.any.keys('a', 'b');
*
* Note that `.all` is used by default when neither `.all` nor `.any` appear
* earlier in the chain. However, it's often best to add `.all` anyway because
* it improves readability.
*
* // Both assertions are identical
* expect({a: 1, b: 2}).to.have.all.keys('a', 'b'); // Recommended
* expect({a: 1, b: 2}).to.have.keys('a', 'b'); // Not recommended
*
* Add `.include` earlier in the chain to require that the target's keys be a
* superset of the expected keys, rather than identical sets.
*
* // Target object's keys are a superset of ['a', 'b'] but not identical
* expect({a: 1, b: 2, c: 3}).to.include.all.keys('a', 'b');
* expect({a: 1, b: 2, c: 3}).to.not.have.all.keys('a', 'b');
*
* However, if `.any` and `.include` are combined, only the `.any` takes
* effect. The `.include` is ignored in this case.
*
* // Both assertions are identical
* expect({a: 1}).to.have.any.keys('a', 'b');
* expect({a: 1}).to.include.any.keys('a', 'b');
*
* A custom error message can be given as the second argument to `expect`.
*
* expect({a: 1}, 'nooo why fail??').to.have.key('b');
*
* The alias `.key` can be used interchangeably with `.keys`.
*
* @name keys
* @alias key
* @param {...String|Array|Object} keys
* @namespace BDD
* @api public
*/
function assertKeys (keys) {
var obj = flag(this, 'object')
, objType = _.type(obj)
, keysType = _.type(keys)
, ssfi = flag(this, 'ssfi')
, isDeep = flag(this, 'deep')
, str
, deepStr = ''
, actual
, ok = true
, flagMsg = flag(this, 'message');
flagMsg = flagMsg ? flagMsg + ': ' : '';
var mixedArgsMsg = flagMsg + 'when testing keys against an object or an array you must give a single Array|Object|String argument or multiple String arguments';
if (objType === 'Map' || objType === 'Set') {
deepStr = isDeep ? 'deeply ' : '';
actual = [];
// Map and Set '.keys' aren't supported in IE 11. Therefore, use .forEach.
obj.forEach(function (val, key) { actual.push(key) });
if (keysType !== 'Array') {
keys = Array.prototype.slice.call(arguments);
}
} else {
actual = _.getOwnEnumerableProperties(obj);
switch (keysType) {
case 'Array':
if (arguments.length > 1) {
throw new AssertionError(mixedArgsMsg, undefined, ssfi);
}
break;
case 'Object':
if (arguments.length > 1) {
throw new AssertionError(mixedArgsMsg, undefined, ssfi);
}
keys = Object.keys(keys);
break;
default:
keys = Array.prototype.slice.call(arguments);
}
// Only stringify non-Symbols because Symbols would become "Symbol()"
keys = keys.map(function (val) {
return typeof val === 'symbol' ? val : String(val);
});
}
if (!keys.length) {
throw new AssertionError(flagMsg + 'keys required', undefined, ssfi);
}
var len = keys.length
, any = flag(this, 'any')
, all = flag(this, 'all')
, expected = keys;
if (!any && !all) {
all = true;
}
// Has any
if (any) {
ok = expected.some(function(expectedKey) {
return actual.some(function(actualKey) {
if (isDeep) {
return _.eql(expectedKey, actualKey);
} else {
return expectedKey === actualKey;
}
});
});
}
// Has all
if (all) {
ok = expected.every(function(expectedKey) {
return actual.some(function(actualKey) {
if (isDeep) {
return _.eql(expectedKey, actualKey);
} else {
return expectedKey === actualKey;
}
});
});
if (!flag(this, 'contains')) {
ok = ok && keys.length == actual.length;
}
}
// Key string
if (len > 1) {
keys = keys.map(function(key) {
return _.inspect(key);
});
var last = keys.pop();
if (all) {
str = keys.join(', ') + ', and ' + last;
}
if (any) {
str = keys.join(', ') + ', or ' + last;
}
} else {
str = _.inspect(keys[0]);
}
// Form
str = (len > 1 ? 'keys ' : 'key ') + str;
// Have / include
str = (flag(this, 'contains') ? 'contain ' : 'have ') + str;
// Assertion
this.assert(
ok
, 'expected #{this} to ' + deepStr + str
, 'expected #{this} to not ' + deepStr + str
, expected.slice(0).sort(_.compareByInspect)
, actual.sort(_.compareByInspect)
, true
);
}
Assertion.addMethod('keys', assertKeys);
Assertion.addMethod('key', assertKeys);
/**
* ### .throw([errorLike], [errMsgMatcher], [msg])
*
* When no arguments are provided, `.throw` invokes the target function and
* asserts that an error is thrown.
*
* var badFn = function () { throw new TypeError('Illegal salmon!'); };
*
* expect(badFn).to.throw();
*
* When one argument is provided, and it's an error constructor, `.throw`
* invokes the target function and asserts that an error is thrown that's an
* instance of that error constructor.
*
* var badFn = function () { throw new TypeError('Illegal salmon!'); };
*
* expect(badFn).to.throw(TypeError);
*
* When one argument is provided, and it's an error instance, `.throw` invokes
* the target function and asserts that an error is thrown that's strictly
* (`===`) equal to that error instance.
*
* var err = new TypeError('Illegal salmon!');
* var badFn = function () { throw err; };
*
* expect(badFn).to.throw(err);
*
* When one argument is provided, and it's a string, `.throw` invokes the
* target function and asserts that an error is thrown with a message that
* contains that string.
*
* var badFn = function () { throw new TypeError('Illegal salmon!'); };
*
* expect(badFn).to.throw('salmon');
*
* When one argument is provided, and it's a regular expression, `.throw`
* invokes the target function and asserts that an error is thrown with a
* message that matches that regular expression.
*
* var badFn = function () { throw new TypeError('Illegal salmon!'); };
*
* expect(badFn).to.throw(/salmon/);
*
* When two arguments are provided, and the first is an error instance or
* constructor, and the second is a string or regular expression, `.throw`
* invokes the function and asserts that an error is thrown that fulfills both
* conditions as described above.
*
* var err = new TypeError('Illegal salmon!');
* var badFn = function () { throw err; };
*
* expect(badFn).to.throw(TypeError, 'salmon');
* expect(badFn).to.throw(TypeError, /salmon/);
* expect(badFn).to.throw(err, 'salmon');
* expect(badFn).to.throw(err, /salmon/);
*
* Add `.not` earlier in the chain to negate `.throw`.
*
* var goodFn = function () {};
*
* expect(goodFn).to.not.throw();
*
* However, it's dangerous to negate `.throw` when providing any arguments.
* The problem is that it creates uncertain expectations by asserting that the
* target either doesn't throw an error, or that it throws an error but of a
* different type than the given type, or that it throws an error of the given
* type but with a message that doesn't include the given string. It's often
* best to identify the exact output that's expected, and then write an
* assertion that only accepts that exact output.
*
* When the target isn't expected to throw an error, it's often best to assert
* exactly that.
*
* var goodFn = function () {};
*
* expect(goodFn).to.not.throw(); // Recommended
* expect(goodFn).to.not.throw(ReferenceError, 'x'); // Not recommended
*
* When the target is expected to throw an error, it's often best to assert
* that the error is of its expected type, and has a message that includes an
* expected string, rather than asserting that it doesn't have one of many
* unexpected types, and doesn't have a message that includes some string.
*
* var badFn = function () { throw new TypeError('Illegal salmon!'); };
*
* expect(badFn).to.throw(TypeError, 'salmon'); // Recommended
* expect(badFn).to.not.throw(ReferenceError, 'x'); // Not recommended
*
* `.throw` changes the target of any assertions that follow in the chain to
* be the error object that's thrown.
*
* var err = new TypeError('Illegal salmon!');
* err.code = 42;
* var badFn = function () { throw err; };
*
* expect(badFn).to.throw(TypeError).with.property('code', 42);
*
* `.throw` accepts an optional `msg` argument which is a custom error message
* to show when the assertion fails. The message can also be given as the
* second argument to `expect`. When not providing two arguments, always use
* the second form.
*
* var goodFn = function () {};
*
* expect(goodFn).to.throw(TypeError, 'x', 'nooo why fail??');
* expect(goodFn, 'nooo why fail??').to.throw();
*
* Due to limitations in ES5, `.throw` may not always work as expected when
* using a transpiler such as Babel or TypeScript. In particular, it may
* produce unexpected results when subclassing the built-in `Error` object and
* then passing the subclassed constructor to `.throw`. See your transpiler's
* docs for details:
*
* - ([Babel](https://babeljs.io/docs/usage/caveats/#classes))
* - ([TypeScript](https://github.com/Microsoft/TypeScript/wiki/Breaking-Changes#extending-built-ins-like-error-array-and-map-may-no-longer-work))
*
* Beware of some common mistakes when using the `throw` assertion. One common
* mistake is to accidentally invoke the function yourself instead of letting
* the `throw` assertion invoke the function for you. For example, when
* testing if a function named `fn` throws, provide `fn` instead of `fn()` as
* the target for the assertion.
*
* expect(fn).to.throw(); // Good! Tests `fn` as desired
* expect(fn()).to.throw(); // Bad! Tests result of `fn()`, not `fn`
*
* If you need to assert that your function `fn` throws when passed certain
* arguments, then wrap a call to `fn` inside of another function.
*
* expect(function () { fn(42); }).to.throw(); // Function expression
* expect(() => fn(42)).to.throw(); // ES6 arrow function
*
* Another common mistake is to provide an object method (or any stand-alone
* function that relies on `this`) as the target of the assertion. Doing so is
* problematic because the `this` context will be lost when the function is
* invoked by `.throw`; there's no way for it to know what `this` is supposed
* to be. There are two ways around this problem. One solution is to wrap the
* method or function call inside of another function. Another solution is to
* use `bind`.
*
* expect(function () { cat.meow(); }).to.throw(); // Function expression
* expect(() => cat.meow()).to.throw(); // ES6 arrow function
* expect(cat.meow.bind(cat)).to.throw(); // Bind
*
* Finally, it's worth mentioning that it's a best practice in JavaScript to
* only throw `Error` and derivatives of `Error` such as `ReferenceError`,
* `TypeError`, and user-defined objects that extend `Error`. No other type of
* value will generate a stack trace when initialized. With that said, the
* `throw` assertion does technically support any type of value being thrown,
* not just `Error` and its derivatives.
*
* The aliases `.throws` and `.Throw` can be used interchangeably with
* `.throw`.
*
* @name throw
* @alias throws
* @alias Throw
* @param {Error|ErrorConstructor} errorLike
* @param {String|RegExp} errMsgMatcher error message
* @param {String} msg _optional_
* @see https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Error#Error_types
* @returns error for chaining (null if no error)
* @namespace BDD
* @api public
*/
function assertThrows (errorLike, errMsgMatcher, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, ssfi = flag(this, 'ssfi')
, flagMsg = flag(this, 'message')
, negate = flag(this, 'negate') || false;
new Assertion(obj, flagMsg, ssfi, true).is.a('function');
if (errorLike instanceof RegExp || typeof errorLike === 'string') {
errMsgMatcher = errorLike;
errorLike = null;
}
var caughtErr;
try {
obj();
} catch (err) {
caughtErr = err;
}
// If we have the negate flag enabled and at least one valid argument it means we do expect an error
// but we want it to match a given set of criteria
var everyArgIsUndefined = errorLike === undefined && errMsgMatcher === undefined;
// If we've got the negate flag enabled and both args, we should only fail if both aren't compatible
// See Issue #551 and PR #683@GitHub
var everyArgIsDefined = Boolean(errorLike && errMsgMatcher);
var errorLikeFail = false;
var errMsgMatcherFail = false;
// Checking if error was thrown
if (everyArgIsUndefined || !everyArgIsUndefined && !negate) {
// We need this to display results correctly according to their types
var errorLikeString = 'an error';
if (errorLike instanceof Error) {
errorLikeString = '#{exp}';
} else if (errorLike) {
errorLikeString = _.checkError.getConstructorName(errorLike);
}
this.assert(
caughtErr
, 'expected #{this} to throw ' + errorLikeString
, 'expected #{this} to not throw an error but #{act} was thrown'
, errorLike && errorLike.toString()
, (caughtErr instanceof Error ?
caughtErr.toString() : (typeof caughtErr === 'string' ? caughtErr : caughtErr &&
_.checkError.getConstructorName(caughtErr)))
);
}
if (errorLike && caughtErr) {
// We should compare instances only if `errorLike` is an instance of `Error`
if (errorLike instanceof Error) {
var isCompatibleInstance = _.checkError.compatibleInstance(caughtErr, errorLike);
if (isCompatibleInstance === negate) {
// These checks were created to ensure we won't fail too soon when we've got both args and a negate
// See Issue #551 and PR #683@GitHub
if (everyArgIsDefined && negate) {
errorLikeFail = true;
} else {
this.assert(
negate
, 'expected #{this} to throw #{exp} but #{act} was thrown'
, 'expected #{this} to not throw #{exp}' + (caughtErr && !negate ? ' but #{act} was thrown' : '')
, errorLike.toString()
, caughtErr.toString()
);
}
}
}
var isCompatibleConstructor = _.checkError.compatibleConstructor(caughtErr, errorLike);
if (isCompatibleConstructor === negate) {
if (everyArgIsDefined && negate) {
errorLikeFail = true;
} else {
this.assert(
negate
, 'expected #{this} to throw #{exp} but #{act} was thrown'
, 'expected #{this} to not throw #{exp}' + (caughtErr ? ' but #{act} was thrown' : '')
, (errorLike instanceof Error ? errorLike.toString() : errorLike && _.checkError.getConstructorName(errorLike))
, (caughtErr instanceof Error ? caughtErr.toString() : caughtErr && _.checkError.getConstructorName(caughtErr))
);
}
}
}
if (caughtErr && errMsgMatcher !== undefined && errMsgMatcher !== null) {
// Here we check compatible messages
var placeholder = 'including';
if (errMsgMatcher instanceof RegExp) {
placeholder = 'matching'
}
var isCompatibleMessage = _.checkError.compatibleMessage(caughtErr, errMsgMatcher);
if (isCompatibleMessage === negate) {
if (everyArgIsDefined && negate) {
errMsgMatcherFail = true;
} else {
this.assert(
negate
, 'expected #{this} to throw error ' + placeholder + ' #{exp} but got #{act}'
, 'expected #{this} to throw error not ' + placeholder + ' #{exp}'
, errMsgMatcher
, _.checkError.getMessage(caughtErr)
);
}
}
}
// If both assertions failed and both should've matched we throw an error
if (errorLikeFail && errMsgMatcherFail) {
this.assert(
negate
, 'expected #{this} to throw #{exp} but #{act} was thrown'
, 'expected #{this} to not throw #{exp}' + (caughtErr ? ' but #{act} was thrown' : '')
, (errorLike instanceof Error ? errorLike.toString() : errorLike && _.checkError.getConstructorName(errorLike))
, (caughtErr instanceof Error ? caughtErr.toString() : caughtErr && _.checkError.getConstructorName(caughtErr))
);
}
flag(this, 'object', caughtErr);
};
Assertion.addMethod('throw', assertThrows);
Assertion.addMethod('throws', assertThrows);
Assertion.addMethod('Throw', assertThrows);
/**
* ### .respondTo(method[, msg])
*
* When the target is a non-function object, `.respondTo` asserts that the
* target has a method with the given name `method`. The method can be own or
* inherited, and it can be enumerable or non-enumerable.
*
* function Cat () {}
* Cat.prototype.meow = function () {};
*
* expect(new Cat()).to.respondTo('meow');
*
* When the target is a function, `.respondTo` asserts that the target's
* `prototype` property has a method with the given name `method`. Again, the
* method can be own or inherited, and it can be enumerable or non-enumerable.
*
* function Cat () {}
* Cat.prototype.meow = function () {};
*
* expect(Cat).to.respondTo('meow');
*
* Add `.itself` earlier in the chain to force `.respondTo` to treat the
* target as a non-function object, even if it's a function. Thus, it asserts
* that the target has a method with the given name `method`, rather than
* asserting that the target's `prototype` property has a method with the
* given name `method`.
*
* function Cat () {}
* Cat.prototype.meow = function () {};
* Cat.hiss = function () {};
*
* expect(Cat).itself.to.respondTo('hiss').but.not.respondTo('meow');
*
* When not adding `.itself`, it's important to check the target's type before
* using `.respondTo`. See the `.a` doc for info on checking a target's type.
*
* function Cat () {}
* Cat.prototype.meow = function () {};
*
* expect(new Cat()).to.be.an('object').that.respondsTo('meow');
*
* Add `.not` earlier in the chain to negate `.respondTo`.
*
* function Dog () {}
* Dog.prototype.bark = function () {};
*
* expect(new Dog()).to.not.respondTo('meow');
*
* `.respondTo` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`.
*
* expect({}).to.respondTo('meow', 'nooo why fail??');
* expect({}, 'nooo why fail??').to.respondTo('meow');
*
* The alias `.respondsTo` can be used interchangeably with `.respondTo`.
*
* @name respondTo
* @alias respondsTo
* @param {String} method
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function respondTo (method, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, itself = flag(this, 'itself')
, context = ('function' === typeof obj && !itself)
? obj.prototype[method]
: obj[method];
this.assert(
'function' === typeof context
, 'expected #{this} to respond to ' + _.inspect(method)
, 'expected #{this} to not respond to ' + _.inspect(method)
);
}
Assertion.addMethod('respondTo', respondTo);
Assertion.addMethod('respondsTo', respondTo);
/**
* ### .itself
*
* Forces all `.respondTo` assertions that follow in the chain to behave as if
* the target is a non-function object, even if it's a function. Thus, it
* causes `.respondTo` to assert that the target has a method with the given
* name, rather than asserting that the target's `prototype` property has a
* method with the given name.
*
* function Cat () {}
* Cat.prototype.meow = function () {};
* Cat.hiss = function () {};
*
* expect(Cat).itself.to.respondTo('hiss').but.not.respondTo('meow');
*
* @name itself
* @namespace BDD
* @api public
*/
Assertion.addProperty('itself', function () {
flag(this, 'itself', true);
});
/**
* ### .satisfy(matcher[, msg])
*
* Invokes the given `matcher` function with the target being passed as the
* first argument, and asserts that the value returned is truthy.
*
* expect(1).to.satisfy(function(num) {
* return num > 0;
* });
*
* Add `.not` earlier in the chain to negate `.satisfy`.
*
* expect(1).to.not.satisfy(function(num) {
* return num > 2;
* });
*
* `.satisfy` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`.
*
* expect(1).to.satisfy(function(num) {
* return num > 2;
* }, 'nooo why fail??');
*
* expect(1, 'nooo why fail??').to.satisfy(function(num) {
* return num > 2;
* });
*
* The alias `.satisfies` can be used interchangeably with `.satisfy`.
*
* @name satisfy
* @alias satisfies
* @param {Function} matcher
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function satisfy (matcher, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object');
var result = matcher(obj);
this.assert(
result
, 'expected #{this} to satisfy ' + _.objDisplay(matcher)
, 'expected #{this} to not satisfy' + _.objDisplay(matcher)
, flag(this, 'negate') ? false : true
, result
);
}
Assertion.addMethod('satisfy', satisfy);
Assertion.addMethod('satisfies', satisfy);
/**
* ### .closeTo(expected, delta[, msg])
*
* Asserts that the target is a number that's within a given +/- `delta` range
* of the given number `expected`. However, it's often best to assert that the
* target is equal to its expected value.
*
* // Recommended
* expect(1.5).to.equal(1.5);
*
* // Not recommended
* expect(1.5).to.be.closeTo(1, 0.5);
* expect(1.5).to.be.closeTo(2, 0.5);
* expect(1.5).to.be.closeTo(1, 1);
*
* Add `.not` earlier in the chain to negate `.closeTo`.
*
* expect(1.5).to.equal(1.5); // Recommended
* expect(1.5).to.not.be.closeTo(3, 1); // Not recommended
*
* `.closeTo` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`.
*
* expect(1.5).to.be.closeTo(3, 1, 'nooo why fail??');
* expect(1.5, 'nooo why fail??').to.be.closeTo(3, 1);
*
* The alias `.approximately` can be used interchangeably with `.closeTo`.
*
* @name closeTo
* @alias approximately
* @param {Number} expected
* @param {Number} delta
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function closeTo(expected, delta, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, flagMsg = flag(this, 'message')
, ssfi = flag(this, 'ssfi');
new Assertion(obj, flagMsg, ssfi, true).is.a('number');
if (typeof expected !== 'number' || typeof delta !== 'number') {
flagMsg = flagMsg ? flagMsg + ': ' : '';
throw new AssertionError(
flagMsg + 'the arguments to closeTo or approximately must be numbers',
undefined,
ssfi
);
}
this.assert(
Math.abs(obj - expected) <= delta
, 'expected #{this} to be close to ' + expected + ' +/- ' + delta
, 'expected #{this} not to be close to ' + expected + ' +/- ' + delta
);
}
Assertion.addMethod('closeTo', closeTo);
Assertion.addMethod('approximately', closeTo);
// Note: Duplicates are ignored if testing for inclusion instead of sameness.
function isSubsetOf(subset, superset, cmp, contains, ordered) {
if (!contains) {
if (subset.length !== superset.length) return false;
superset = superset.slice();
}
return subset.every(function(elem, idx) {
if (ordered) return cmp ? cmp(elem, superset[idx]) : elem === superset[idx];
if (!cmp) {
var matchIdx = superset.indexOf(elem);
if (matchIdx === -1) return false;
// Remove match from superset so not counted twice if duplicate in subset.
if (!contains) superset.splice(matchIdx, 1);
return true;
}
return superset.some(function(elem2, matchIdx) {
if (!cmp(elem, elem2)) return false;
// Remove match from superset so not counted twice if duplicate in subset.
if (!contains) superset.splice(matchIdx, 1);
return true;
});
});
}
/**
* ### .members(set[, msg])
*
* Asserts that the target array has the same members as the given array
* `set`.
*
* expect([1, 2, 3]).to.have.members([2, 1, 3]);
* expect([1, 2, 2]).to.have.members([2, 1, 2]);
*
* By default, members are compared using strict (`===`) equality. Add `.deep`
* earlier in the chain to use deep equality instead. See the `deep-eql`
* project page for info on the deep equality algorithm:
* https://github.com/chaijs/deep-eql.
*
* // Target array deeply (but not strictly) has member `{a: 1}`
* expect([{a: 1}]).to.have.deep.members([{a: 1}]);
* expect([{a: 1}]).to.not.have.members([{a: 1}]);
*
* By default, order doesn't matter. Add `.ordered` earlier in the chain to
* require that members appear in the same order.
*
* expect([1, 2, 3]).to.have.ordered.members([1, 2, 3]);
* expect([1, 2, 3]).to.have.members([2, 1, 3])
* .but.not.ordered.members([2, 1, 3]);
*
* By default, both arrays must be the same size. Add `.include` earlier in
* the chain to require that the target's members be a superset of the
* expected members. Note that duplicates are ignored in the subset when
* `.include` is added.
*
* // Target array is a superset of [1, 2] but not identical
* expect([1, 2, 3]).to.include.members([1, 2]);
* expect([1, 2, 3]).to.not.have.members([1, 2]);
*
* // Duplicates in the subset are ignored
* expect([1, 2, 3]).to.include.members([1, 2, 2, 2]);
*
* `.deep`, `.ordered`, and `.include` can all be combined. However, if
* `.include` and `.ordered` are combined, the ordering begins at the start of
* both arrays.
*
* expect([{a: 1}, {b: 2}, {c: 3}])
* .to.include.deep.ordered.members([{a: 1}, {b: 2}])
* .but.not.include.deep.ordered.members([{b: 2}, {c: 3}]);
*
* Add `.not` earlier in the chain to negate `.members`. However, it's
* dangerous to do so. The problem is that it creates uncertain expectations
* by asserting that the target array doesn't have all of the same members as
* the given array `set` but may or may not have some of them. It's often best
* to identify the exact output that's expected, and then write an assertion
* that only accepts that exact output.
*
* expect([1, 2]).to.not.include(3).and.not.include(4); // Recommended
* expect([1, 2]).to.not.have.members([3, 4]); // Not recommended
*
* `.members` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`.
*
* expect([1, 2]).to.have.members([1, 2, 3], 'nooo why fail??');
* expect([1, 2], 'nooo why fail??').to.have.members([1, 2, 3]);
*
* @name members
* @param {Array} set
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
Assertion.addMethod('members', function (subset, msg) {
if (msg) flag(this, 'message', msg);
var obj = flag(this, 'object')
, flagMsg = flag(this, 'message')
, ssfi = flag(this, 'ssfi');
new Assertion(obj, flagMsg, ssfi, true).to.be.an('array');
new Assertion(subset, flagMsg, ssfi, true).to.be.an('array');
var contains = flag(this, 'contains');
var ordered = flag(this, 'ordered');
var subject, failMsg, failNegateMsg;
if (contains) {
subject = ordered ? 'an ordered superset' : 'a superset';
failMsg = 'expected #{this} to be ' + subject + ' of #{exp}';
failNegateMsg = 'expected #{this} to not be ' + subject + ' of #{exp}';
} else {
subject = ordered ? 'ordered members' : 'members';
failMsg = 'expected #{this} to have the same ' + subject + ' as #{exp}';
failNegateMsg = 'expected #{this} to not have the same ' + subject + ' as #{exp}';
}
var cmp = flag(this, 'deep') ? _.eql : undefined;
this.assert(
isSubsetOf(subset, obj, cmp, contains, ordered)
, failMsg
, failNegateMsg
, subset
, obj
, true
);
});
/**
* ### .oneOf(list[, msg])
*
* Asserts that the target is a member of the given array `list`. However,
* it's often best to assert that the target is equal to its expected value.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.be.oneOf([1, 2, 3]); // Not recommended
*
* Comparisons are performed using strict (`===`) equality.
*
* Add `.not` earlier in the chain to negate `.oneOf`.
*
* expect(1).to.equal(1); // Recommended
* expect(1).to.not.be.oneOf([2, 3, 4]); // Not recommended
*
* `.oneOf` accepts an optional `msg` argument which is a custom error message
* to show when the assertion fails. The message can also be given as the
* second argument to `expect`.
*
* expect(1).to.be.oneOf([2, 3, 4], 'nooo why fail??');
* expect(1, 'nooo why fail??').to.be.oneOf([2, 3, 4]);
*
* @name oneOf
* @param {Array<*>} list
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function oneOf (list, msg) {
if (msg) flag(this, 'message', msg);
var expected = flag(this, 'object')
, flagMsg = flag(this, 'message')
, ssfi = flag(this, 'ssfi');
new Assertion(list, flagMsg, ssfi, true).to.be.an('array');
this.assert(
list.indexOf(expected) > -1
, 'expected #{this} to be one of #{exp}'
, 'expected #{this} to not be one of #{exp}'
, list
, expected
);
}
Assertion.addMethod('oneOf', oneOf);
/**
* ### .change(subject[, prop[, msg]])
*
* When one argument is provided, `.change` asserts that the given function
* `subject` returns a different value when it's invoked before the target
* function compared to when it's invoked afterward. However, it's often best
* to assert that `subject` is equal to its expected value.
*
* var dots = ''
* , addDot = function () { dots += '.'; }
* , getDots = function () { return dots; };
*
* // Recommended
* expect(getDots()).to.equal('');
* addDot();
* expect(getDots()).to.equal('.');
*
* // Not recommended
* expect(addDot).to.change(getDots);
*
* When two arguments are provided, `.change` asserts that the value of the
* given object `subject`'s `prop` property is different before invoking the
* target function compared to afterward.
*
* var myObj = {dots: ''}
* , addDot = function () { myObj.dots += '.'; };
*
* // Recommended
* expect(myObj).to.have.property('dots', '');
* addDot();
* expect(myObj).to.have.property('dots', '.');
*
* // Not recommended
* expect(addDot).to.change(myObj, 'dots');
*
* Strict (`===`) equality is used to compare before and after values.
*
* Add `.not` earlier in the chain to negate `.change`.
*
* var dots = ''
* , noop = function () {}
* , getDots = function () { return dots; };
*
* expect(noop).to.not.change(getDots);
*
* var myObj = {dots: ''}
* , noop = function () {};
*
* expect(noop).to.not.change(myObj, 'dots');
*
* `.change` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`. When not providing two arguments, always
* use the second form.
*
* var myObj = {dots: ''}
* , addDot = function () { myObj.dots += '.'; };
*
* expect(addDot).to.not.change(myObj, 'dots', 'nooo why fail??');
*
* var dots = ''
* , addDot = function () { dots += '.'; }
* , getDots = function () { return dots; };
*
* expect(addDot, 'nooo why fail??').to.not.change(getDots);
*
* `.change` also causes all `.by` assertions that follow in the chain to
* assert how much a numeric subject was increased or decreased by. However,
* it's dangerous to use `.change.by`. The problem is that it creates
* uncertain expectations by asserting that the subject either increases by
* the given delta, or that it decreases by the given delta. It's often best
* to identify the exact output that's expected, and then write an assertion
* that only accepts that exact output.
*
* var myObj = {val: 1}
* , addTwo = function () { myObj.val += 2; }
* , subtractTwo = function () { myObj.val -= 2; };
*
* expect(addTwo).to.increase(myObj, 'val').by(2); // Recommended
* expect(addTwo).to.change(myObj, 'val').by(2); // Not recommended
*
* expect(subtractTwo).to.decrease(myObj, 'val').by(2); // Recommended
* expect(subtractTwo).to.change(myObj, 'val').by(2); // Not recommended
*
* The alias `.changes` can be used interchangeably with `.change`.
*
* @name change
* @alias changes
* @param {String} subject
* @param {String} prop name _optional_
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertChanges (subject, prop, msg) {
if (msg) flag(this, 'message', msg);
var fn = flag(this, 'object')
, flagMsg = flag(this, 'message')
, ssfi = flag(this, 'ssfi');
new Assertion(fn, flagMsg, ssfi, true).is.a('function');
var initial;
if (!prop) {
new Assertion(subject, flagMsg, ssfi, true).is.a('function');
initial = subject();
} else {
new Assertion(subject, flagMsg, ssfi, true).to.have.property(prop);
initial = subject[prop];
}
fn();
var final = prop === undefined || prop === null ? subject() : subject[prop];
var msgObj = prop === undefined || prop === null ? initial : '.' + prop;
// This gets flagged because of the .by(delta) assertion
flag(this, 'deltaMsgObj', msgObj);
flag(this, 'initialDeltaValue', initial);
flag(this, 'finalDeltaValue', final);
flag(this, 'deltaBehavior', 'change');
flag(this, 'realDelta', final !== initial);
this.assert(
initial !== final
, 'expected ' + msgObj + ' to change'
, 'expected ' + msgObj + ' to not change'
);
}
Assertion.addMethod('change', assertChanges);
Assertion.addMethod('changes', assertChanges);
/**
* ### .increase(subject[, prop[, msg]])
*
* When one argument is provided, `.increase` asserts that the given function
* `subject` returns a greater number when it's invoked after invoking the
* target function compared to when it's invoked beforehand. `.increase` also
* causes all `.by` assertions that follow in the chain to assert how much
* greater of a number is returned. It's often best to assert that the return
* value increased by the expected amount, rather than asserting it increased
* by any amount.
*
* var val = 1
* , addTwo = function () { val += 2; }
* , getVal = function () { return val; };
*
* expect(addTwo).to.increase(getVal).by(2); // Recommended
* expect(addTwo).to.increase(getVal); // Not recommended
*
* When two arguments are provided, `.increase` asserts that the value of the
* given object `subject`'s `prop` property is greater after invoking the
* target function compared to beforehand.
*
* var myObj = {val: 1}
* , addTwo = function () { myObj.val += 2; };
*
* expect(addTwo).to.increase(myObj, 'val').by(2); // Recommended
* expect(addTwo).to.increase(myObj, 'val'); // Not recommended
*
* Add `.not` earlier in the chain to negate `.increase`. However, it's
* dangerous to do so. The problem is that it creates uncertain expectations
* by asserting that the subject either decreases, or that it stays the same.
* It's often best to identify the exact output that's expected, and then
* write an assertion that only accepts that exact output.
*
* When the subject is expected to decrease, it's often best to assert that it
* decreased by the expected amount.
*
* var myObj = {val: 1}
* , subtractTwo = function () { myObj.val -= 2; };
*
* expect(subtractTwo).to.decrease(myObj, 'val').by(2); // Recommended
* expect(subtractTwo).to.not.increase(myObj, 'val'); // Not recommended
*
* When the subject is expected to stay the same, it's often best to assert
* exactly that.
*
* var myObj = {val: 1}
* , noop = function () {};
*
* expect(noop).to.not.change(myObj, 'val'); // Recommended
* expect(noop).to.not.increase(myObj, 'val'); // Not recommended
*
* `.increase` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`. When not providing two arguments, always
* use the second form.
*
* var myObj = {val: 1}
* , noop = function () {};
*
* expect(noop).to.increase(myObj, 'val', 'nooo why fail??');
*
* var val = 1
* , noop = function () {}
* , getVal = function () { return val; };
*
* expect(noop, 'nooo why fail??').to.increase(getVal);
*
* The alias `.increases` can be used interchangeably with `.increase`.
*
* @name increase
* @alias increases
* @param {String|Function} subject
* @param {String} prop name _optional_
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertIncreases (subject, prop, msg) {
if (msg) flag(this, 'message', msg);
var fn = flag(this, 'object')
, flagMsg = flag(this, 'message')
, ssfi = flag(this, 'ssfi');
new Assertion(fn, flagMsg, ssfi, true).is.a('function');
var initial;
if (!prop) {
new Assertion(subject, flagMsg, ssfi, true).is.a('function');
initial = subject();
} else {
new Assertion(subject, flagMsg, ssfi, true).to.have.property(prop);
initial = subject[prop];
}
// Make sure that the target is a number
new Assertion(initial, flagMsg, ssfi, true).is.a('number');
fn();
var final = prop === undefined || prop === null ? subject() : subject[prop];
var msgObj = prop === undefined || prop === null ? initial : '.' + prop;
flag(this, 'deltaMsgObj', msgObj);
flag(this, 'initialDeltaValue', initial);
flag(this, 'finalDeltaValue', final);
flag(this, 'deltaBehavior', 'increase');
flag(this, 'realDelta', final - initial);
this.assert(
final - initial > 0
, 'expected ' + msgObj + ' to increase'
, 'expected ' + msgObj + ' to not increase'
);
}
Assertion.addMethod('increase', assertIncreases);
Assertion.addMethod('increases', assertIncreases);
/**
* ### .decrease(subject[, prop[, msg]])
*
* When one argument is provided, `.decrease` asserts that the given function
* `subject` returns a lesser number when it's invoked after invoking the
* target function compared to when it's invoked beforehand. `.decrease` also
* causes all `.by` assertions that follow in the chain to assert how much
* lesser of a number is returned. It's often best to assert that the return
* value decreased by the expected amount, rather than asserting it decreased
* by any amount.
*
* var val = 1
* , subtractTwo = function () { val -= 2; }
* , getVal = function () { return val; };
*
* expect(subtractTwo).to.decrease(getVal).by(2); // Recommended
* expect(subtractTwo).to.decrease(getVal); // Not recommended
*
* When two arguments are provided, `.decrease` asserts that the value of the
* given object `subject`'s `prop` property is lesser after invoking the
* target function compared to beforehand.
*
* var myObj = {val: 1}
* , subtractTwo = function () { myObj.val -= 2; };
*
* expect(subtractTwo).to.decrease(myObj, 'val').by(2); // Recommended
* expect(subtractTwo).to.decrease(myObj, 'val'); // Not recommended
*
* Add `.not` earlier in the chain to negate `.decrease`. However, it's
* dangerous to do so. The problem is that it creates uncertain expectations
* by asserting that the subject either increases, or that it stays the same.
* It's often best to identify the exact output that's expected, and then
* write an assertion that only accepts that exact output.
*
* When the subject is expected to increase, it's often best to assert that it
* increased by the expected amount.
*
* var myObj = {val: 1}
* , addTwo = function () { myObj.val += 2; };
*
* expect(addTwo).to.increase(myObj, 'val').by(2); // Recommended
* expect(addTwo).to.not.decrease(myObj, 'val'); // Not recommended
*
* When the subject is expected to stay the same, it's often best to assert
* exactly that.
*
* var myObj = {val: 1}
* , noop = function () {};
*
* expect(noop).to.not.change(myObj, 'val'); // Recommended
* expect(noop).to.not.decrease(myObj, 'val'); // Not recommended
*
* `.decrease` accepts an optional `msg` argument which is a custom error
* message to show when the assertion fails. The message can also be given as
* the second argument to `expect`. When not providing two arguments, always
* use the second form.
*
* var myObj = {val: 1}
* , noop = function () {};
*
* expect(noop).to.decrease(myObj, 'val', 'nooo why fail??');
*
* var val = 1
* , noop = function () {}
* , getVal = function () { return val; };
*
* expect(noop, 'nooo why fail??').to.decrease(getVal);
*
* The alias `.decreases` can be used interchangeably with `.decrease`.
*
* @name decrease
* @alias decreases
* @param {String|Function} subject
* @param {String} prop name _optional_
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertDecreases (subject, prop, msg) {
if (msg) flag(this, 'message', msg);
var fn = flag(this, 'object')
, flagMsg = flag(this, 'message')
, ssfi = flag(this, 'ssfi');
new Assertion(fn, flagMsg, ssfi, true).is.a('function');
var initial;
if (!prop) {
new Assertion(subject, flagMsg, ssfi, true).is.a('function');
initial = subject();
} else {
new Assertion(subject, flagMsg, ssfi, true).to.have.property(prop);
initial = subject[prop];
}
// Make sure that the target is a number
new Assertion(initial, flagMsg, ssfi, true).is.a('number');
fn();
var final = prop === undefined || prop === null ? subject() : subject[prop];
var msgObj = prop === undefined || prop === null ? initial : '.' + prop;
flag(this, 'deltaMsgObj', msgObj);
flag(this, 'initialDeltaValue', initial);
flag(this, 'finalDeltaValue', final);
flag(this, 'deltaBehavior', 'decrease');
flag(this, 'realDelta', initial - final);
this.assert(
final - initial < 0
, 'expected ' + msgObj + ' to decrease'
, 'expected ' + msgObj + ' to not decrease'
);
}
Assertion.addMethod('decrease', assertDecreases);
Assertion.addMethod('decreases', assertDecreases);
/**
* ### .by(delta[, msg])
*
* When following an `.increase` assertion in the chain, `.by` asserts that
* the subject of the `.increase` assertion increased by the given `delta`.
*
* var myObj = {val: 1}
* , addTwo = function () { myObj.val += 2; };
*
* expect(addTwo).to.increase(myObj, 'val').by(2);
*
* When following a `.decrease` assertion in the chain, `.by` asserts that the
* subject of the `.decrease` assertion decreased by the given `delta`.
*
* var myObj = {val: 1}
* , subtractTwo = function () { myObj.val -= 2; };
*
* expect(subtractTwo).to.decrease(myObj, 'val').by(2);
*
* When following a `.change` assertion in the chain, `.by` asserts that the
* subject of the `.change` assertion either increased or decreased by the
* given `delta`. However, it's dangerous to use `.change.by`. The problem is
* that it creates uncertain expectations. It's often best to identify the
* exact output that's expected, and then write an assertion that only accepts
* that exact output.
*
* var myObj = {val: 1}
* , addTwo = function () { myObj.val += 2; }
* , subtractTwo = function () { myObj.val -= 2; };
*
* expect(addTwo).to.increase(myObj, 'val').by(2); // Recommended
* expect(addTwo).to.change(myObj, 'val').by(2); // Not recommended
*
* expect(subtractTwo).to.decrease(myObj, 'val').by(2); // Recommended
* expect(subtractTwo).to.change(myObj, 'val').by(2); // Not recommended
*
* Add `.not` earlier in the chain to negate `.by`. However, it's often best
* to assert that the subject changed by its expected delta, rather than
* asserting that it didn't change by one of countless unexpected deltas.
*
* var myObj = {val: 1}
* , addTwo = function () { myObj.val += 2; };
*
* // Recommended
* expect(addTwo).to.increase(myObj, 'val').by(2);
*
* // Not recommended
* expect(addTwo).to.increase(myObj, 'val').but.not.by(3);
*
* `.by` accepts an optional `msg` argument which is a custom error message to
* show when the assertion fails. The message can also be given as the second
* argument to `expect`.
*
* var myObj = {val: 1}
* , addTwo = function () { myObj.val += 2; };
*
* expect(addTwo).to.increase(myObj, 'val').by(3, 'nooo why fail??');
* expect(addTwo, 'nooo why fail??').to.increase(myObj, 'val').by(3);
*
* @name by
* @param {Number} delta
* @param {String} msg _optional_
* @namespace BDD
* @api public
*/
function assertDelta(delta, msg) {
if (msg) flag(this, 'message', msg);
var msgObj = flag(this, 'deltaMsgObj');
var initial = flag(this, 'initialDeltaValue');
var final = flag(this, 'finalDeltaValue');
var behavior = flag(this, 'deltaBehavior');
var realDelta = flag(this, 'realDelta');
var expression;
if (behavior === 'change') {
expression = Math.abs(final - initial) === Math.abs(delta);
} else {
expression = realDelta === Math.abs(delta);
}
this.assert(
expression
, 'expected ' + msgObj + ' to ' + behavior + ' by ' + delta
, 'expected ' + msgObj + ' to not ' + behavior + ' by ' + delta
);
}
Assertion.addMethod('by', assertDelta);
/**
* ### .extensible
*
* Asserts that the target is extensible, which means that new properties can
* be added to it. Primitives are never extensible.
*
* expect({a: 1}).to.be.extensible;
*
* Add `.not` earlier in the chain to negate `.extensible`.
*
* var nonExtensibleObject = Object.preventExtensions({})
* , sealedObject = Object.seal({})
* , frozenObject = Object.freeze({});
*
* expect(nonExtensibleObject).to.not.be.extensible;
* expect(sealedObject).to.not.be.extensible;
* expect(frozenObject).to.not.be.extensible;
* expect(1).to.not.be.extensible;
*
* A custom error message can be given as the second argument to `expect`.
*
* expect(1, 'nooo why fail??').to.be.extensible;
*
* @name extensible
* @namespace BDD
* @api public
*/
Assertion.addProperty('extensible', function() {
var obj = flag(this, 'object');
// In ES5, if the argument to this method is a primitive, then it will cause a TypeError.
// In ES6, a non-object argument will be treated as if it was a non-extensible ordinary object, simply return false.
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/isExtensible
// The following provides ES6 behavior for ES5 environments.
var isExtensible = obj === Object(obj) && Object.isExtensible(obj);
this.assert(
isExtensible
, 'expected #{this} to be extensible'
, 'expected #{this} to not be extensible'
);
});
/**
* ### .sealed
*
* Asserts that the target is sealed, which means that new properties can't be
* added to it, and its existing properties can't be reconfigured or deleted.
* However, it's possible that its existing properties can still be reassigned
* to different values. Primitives are always sealed.
*
* var sealedObject = Object.seal({});
* var frozenObject = Object.freeze({});
*
* expect(sealedObject).to.be.sealed;
* expect(frozenObject).to.be.sealed;
* expect(1).to.be.sealed;
*
* Add `.not` earlier in the chain to negate `.sealed`.
*
* expect({a: 1}).to.not.be.sealed;
*
* A custom error message can be given as the second argument to `expect`.
*
* expect({a: 1}, 'nooo why fail??').to.be.sealed;
*
* @name sealed
* @namespace BDD
* @api public
*/
Assertion.addProperty('sealed', function() {
var obj = flag(this, 'object');
// In ES5, if the argument to this method is a primitive, then it will cause a TypeError.
// In ES6, a non-object argument will be treated as if it was a sealed ordinary object, simply return true.
// See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/isSealed
// The following provides ES6 behavior for ES5 environments.
var isSealed = obj === Object(obj) ? Object.isSealed(obj) : true;
this.assert(
isSealed
, 'expected #{this} to be sealed'
, 'expected #{this} to not be sealed'
);
});
/**
* ### .frozen
*
* Asserts that the target is frozen, which means that new properties can't be
* added to it, and its existing properties can't be reassigned to different
* values, reconfigured, or deleted. Primitives are always frozen.
*
* var frozenObject = Object.freeze({});
*
* expect(frozenObject).to.be.frozen;
* expect(1).to.be.frozen;
*
* Add `.not` earlier in the chain to negate `.frozen`.
*
* expect({a: 1}).to.not.be.frozen;
*
* A custom error message can be given as the second argument to `expect`.
*
* expect({a: 1}, 'nooo why fail??').to.be.frozen;
*
* @name frozen
* @namespace BDD
* @api public
*/
Assertion.addProperty('frozen', function() {
var obj = flag(this, 'object');
// In ES5, if the argument to this method is a primitive, then it will cause a TypeError.
// In ES6, a non-object argument will be treated as if it was a frozen ordinary object, simply return true.
// See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/isFrozen
// The following provides ES6 behavior for ES5 environments.
var isFrozen = obj === Object(obj) ? Object.isFrozen(obj) : true;
this.assert(
isFrozen
, 'expected #{this} to be frozen'
, 'expected #{this} to not be frozen'
);
});
/**
* ### .finite
*
* Asserts that the target is a number, and isn't `NaN` or positive/negative
* `Infinity`.
*
* expect(1).to.be.finite;
*
* Add `.not` earlier in the chain to negate `.finite`. However, it's
* dangerous to do so. The problem is that it creates uncertain expectations
* by asserting that the subject either isn't a number, or that it's `NaN`, or
* that it's positive `Infinity`, or that it's negative `Infinity`. It's often
* best to identify the exact output that's expected, and then write an
* assertion that only accepts that exact output.
*
* When the target isn't expected to be a number, it's often best to assert
* that it's the expected type, rather than asserting that it isn't one of
* many unexpected types.
*
* expect('foo').to.be.a('string'); // Recommended
* expect('foo').to.not.be.finite; // Not recommended
*
* When the target is expected to be `NaN`, it's often best to assert exactly
* that.
*
* expect(NaN).to.be.NaN; // Recommended
* expect(NaN).to.not.be.finite; // Not recommended
*
* When the target is expected to be positive infinity, it's often best to
* assert exactly that.
*
* expect(Infinity).to.equal(Infinity); // Recommended
* expect(Infinity).to.not.be.finite; // Not recommended
*
* When the target is expected to be negative infinity, it's often best to
* assert exactly that.
*
* expect(-Infinity).to.equal(-Infinity); // Recommended
* expect(-Infinity).to.not.be.finite; // Not recommended
*
* A custom error message can be given as the second argument to `expect`.
*
* expect('foo', 'nooo why fail??').to.be.finite;
*
* @name finite
* @namespace BDD
* @api public
*/
Assertion.addProperty('finite', function(msg) {
var obj = flag(this, 'object');
this.assert(
typeof obj === 'number' && isFinite(obj)
, 'expected #{this} to be a finite number'
, 'expected #{this} to not be a finite number'
);
});
};