| /** |
| * @fileoverview enforce the location of single-line statements |
| * @author Teddy Katz |
| */ |
| "use strict"; |
| |
| //------------------------------------------------------------------------------ |
| // Rule Definition |
| //------------------------------------------------------------------------------ |
| |
| const POSITION_SCHEMA = { enum: ["beside", "below", "any"] }; |
| |
| module.exports = { |
| meta: { |
| type: "layout", |
| |
| docs: { |
| description: "enforce the location of single-line statements", |
| category: "Stylistic Issues", |
| recommended: false, |
| url: "https://eslint.org/docs/rules/nonblock-statement-body-position" |
| }, |
| |
| fixable: "whitespace", |
| |
| schema: [ |
| POSITION_SCHEMA, |
| { |
| properties: { |
| overrides: { |
| properties: { |
| if: POSITION_SCHEMA, |
| else: POSITION_SCHEMA, |
| while: POSITION_SCHEMA, |
| do: POSITION_SCHEMA, |
| for: POSITION_SCHEMA |
| }, |
| additionalProperties: false |
| } |
| }, |
| additionalProperties: false |
| } |
| ] |
| }, |
| |
| create(context) { |
| const sourceCode = context.getSourceCode(); |
| |
| //---------------------------------------------------------------------- |
| // Helpers |
| //---------------------------------------------------------------------- |
| |
| /** |
| * Gets the applicable preference for a particular keyword |
| * @param {string} keywordName The name of a keyword, e.g. 'if' |
| * @returns {string} The applicable option for the keyword, e.g. 'beside' |
| */ |
| function getOption(keywordName) { |
| return context.options[1] && context.options[1].overrides && context.options[1].overrides[keywordName] || |
| context.options[0] || |
| "beside"; |
| } |
| |
| /** |
| * Validates the location of a single-line statement |
| * @param {ASTNode} node The single-line statement |
| * @param {string} keywordName The applicable keyword name for the single-line statement |
| * @returns {void} |
| */ |
| function validateStatement(node, keywordName) { |
| const option = getOption(keywordName); |
| |
| if (node.type === "BlockStatement" || option === "any") { |
| return; |
| } |
| |
| const tokenBefore = sourceCode.getTokenBefore(node); |
| |
| if (tokenBefore.loc.end.line === node.loc.start.line && option === "below") { |
| context.report({ |
| node, |
| message: "Expected a linebreak before this statement.", |
| fix: fixer => fixer.insertTextBefore(node, "\n") |
| }); |
| } else if (tokenBefore.loc.end.line !== node.loc.start.line && option === "beside") { |
| context.report({ |
| node, |
| message: "Expected no linebreak before this statement.", |
| fix(fixer) { |
| if (sourceCode.getText().slice(tokenBefore.range[1], node.range[0]).trim()) { |
| return null; |
| } |
| return fixer.replaceTextRange([tokenBefore.range[1], node.range[0]], " "); |
| } |
| }); |
| } |
| } |
| |
| //---------------------------------------------------------------------- |
| // Public |
| //---------------------------------------------------------------------- |
| |
| return { |
| IfStatement(node) { |
| validateStatement(node.consequent, "if"); |
| |
| // Check the `else` node, but don't check 'else if' statements. |
| if (node.alternate && node.alternate.type !== "IfStatement") { |
| validateStatement(node.alternate, "else"); |
| } |
| }, |
| WhileStatement: node => validateStatement(node.body, "while"), |
| DoWhileStatement: node => validateStatement(node.body, "do"), |
| ForStatement: node => validateStatement(node.body, "for"), |
| ForInStatement: node => validateStatement(node.body, "for"), |
| ForOfStatement: node => validateStatement(node.body, "for") |
| }; |
| } |
| }; |