| /** |
| * @fileoverview Rule to check empty newline after "var" statement |
| * @author Gopal Venkatesan |
| * @deprecated |
| */ |
| |
| "use strict"; |
| |
| //------------------------------------------------------------------------------ |
| // Requirements |
| //------------------------------------------------------------------------------ |
| |
| const astUtils = require("./utils/ast-utils"); |
| |
| //------------------------------------------------------------------------------ |
| // Rule Definition |
| //------------------------------------------------------------------------------ |
| |
| module.exports = { |
| meta: { |
| type: "layout", |
| |
| docs: { |
| description: "require or disallow an empty line after variable declarations", |
| category: "Stylistic Issues", |
| recommended: false, |
| url: "https://eslint.org/docs/rules/newline-after-var" |
| }, |
| schema: [ |
| { |
| enum: ["never", "always"] |
| } |
| ], |
| fixable: "whitespace", |
| messages: { |
| expected: "Expected blank line after variable declarations.", |
| unexpected: "Unexpected blank line after variable declarations." |
| }, |
| |
| deprecated: true, |
| |
| replacedBy: ["padding-line-between-statements"] |
| }, |
| |
| create(context) { |
| const sourceCode = context.getSourceCode(); |
| |
| // Default `mode` to "always". |
| const mode = context.options[0] === "never" ? "never" : "always"; |
| |
| // Cache starting and ending line numbers of comments for faster lookup |
| const commentEndLine = sourceCode.getAllComments().reduce((result, token) => { |
| result[token.loc.start.line] = token.loc.end.line; |
| return result; |
| }, {}); |
| |
| |
| //-------------------------------------------------------------------------- |
| // Helpers |
| //-------------------------------------------------------------------------- |
| |
| /** |
| * Gets a token from the given node to compare line to the next statement. |
| * |
| * In general, the token is the last token of the node. However, the token is the second last token if the following conditions satisfy. |
| * |
| * - The last token is semicolon. |
| * - The semicolon is on a different line from the previous token of the semicolon. |
| * |
| * This behavior would address semicolon-less style code. e.g.: |
| * |
| * var foo = 1 |
| * |
| * ;(a || b).doSomething() |
| * |
| * @param {ASTNode} node - The node to get. |
| * @returns {Token} The token to compare line to the next statement. |
| */ |
| function getLastToken(node) { |
| const lastToken = sourceCode.getLastToken(node); |
| |
| if (lastToken.type === "Punctuator" && lastToken.value === ";") { |
| const prevToken = sourceCode.getTokenBefore(lastToken); |
| |
| if (prevToken.loc.end.line !== lastToken.loc.start.line) { |
| return prevToken; |
| } |
| } |
| |
| return lastToken; |
| } |
| |
| /** |
| * Determine if provided keyword is a variable declaration |
| * @private |
| * @param {string} keyword - keyword to test |
| * @returns {boolean} True if `keyword` is a type of var |
| */ |
| function isVar(keyword) { |
| return keyword === "var" || keyword === "let" || keyword === "const"; |
| } |
| |
| /** |
| * Determine if provided keyword is a variant of for specifiers |
| * @private |
| * @param {string} keyword - keyword to test |
| * @returns {boolean} True if `keyword` is a variant of for specifier |
| */ |
| function isForTypeSpecifier(keyword) { |
| return keyword === "ForStatement" || keyword === "ForInStatement" || keyword === "ForOfStatement"; |
| } |
| |
| /** |
| * Determine if provided keyword is an export specifiers |
| * @private |
| * @param {string} nodeType - nodeType to test |
| * @returns {boolean} True if `nodeType` is an export specifier |
| */ |
| function isExportSpecifier(nodeType) { |
| return nodeType === "ExportNamedDeclaration" || nodeType === "ExportSpecifier" || |
| nodeType === "ExportDefaultDeclaration" || nodeType === "ExportAllDeclaration"; |
| } |
| |
| /** |
| * Determine if provided node is the last of their parent block. |
| * @private |
| * @param {ASTNode} node - node to test |
| * @returns {boolean} True if `node` is last of their parent block. |
| */ |
| function isLastNode(node) { |
| const token = sourceCode.getTokenAfter(node); |
| |
| return !token || (token.type === "Punctuator" && token.value === "}"); |
| } |
| |
| /** |
| * Gets the last line of a group of consecutive comments |
| * @param {number} commentStartLine The starting line of the group |
| * @returns {number} The number of the last comment line of the group |
| */ |
| function getLastCommentLineOfBlock(commentStartLine) { |
| const currentCommentEnd = commentEndLine[commentStartLine]; |
| |
| return commentEndLine[currentCommentEnd + 1] ? getLastCommentLineOfBlock(currentCommentEnd + 1) : currentCommentEnd; |
| } |
| |
| /** |
| * Determine if a token starts more than one line after a comment ends |
| * @param {token} token The token being checked |
| * @param {integer} commentStartLine The line number on which the comment starts |
| * @returns {boolean} True if `token` does not start immediately after a comment |
| */ |
| function hasBlankLineAfterComment(token, commentStartLine) { |
| return token.loc.start.line > getLastCommentLineOfBlock(commentStartLine) + 1; |
| } |
| |
| /** |
| * Checks that a blank line exists after a variable declaration when mode is |
| * set to "always", or checks that there is no blank line when mode is set |
| * to "never" |
| * @private |
| * @param {ASTNode} node - `VariableDeclaration` node to test |
| * @returns {void} |
| */ |
| function checkForBlankLine(node) { |
| |
| /* |
| * lastToken is the last token on the node's line. It will usually also be the last token of the node, but it will |
| * sometimes be second-last if there is a semicolon on a different line. |
| */ |
| const lastToken = getLastToken(node), |
| |
| /* |
| * If lastToken is the last token of the node, nextToken should be the token after the node. Otherwise, nextToken |
| * is the last token of the node. |
| */ |
| nextToken = lastToken === sourceCode.getLastToken(node) ? sourceCode.getTokenAfter(node) : sourceCode.getLastToken(node), |
| nextLineNum = lastToken.loc.end.line + 1; |
| |
| // Ignore if there is no following statement |
| if (!nextToken) { |
| return; |
| } |
| |
| // Ignore if parent of node is a for variant |
| if (isForTypeSpecifier(node.parent.type)) { |
| return; |
| } |
| |
| // Ignore if parent of node is an export specifier |
| if (isExportSpecifier(node.parent.type)) { |
| return; |
| } |
| |
| /* |
| * Some coding styles use multiple `var` statements, so do nothing if |
| * the next token is a `var` statement. |
| */ |
| if (nextToken.type === "Keyword" && isVar(nextToken.value)) { |
| return; |
| } |
| |
| // Ignore if it is last statement in a block |
| if (isLastNode(node)) { |
| return; |
| } |
| |
| // Next statement is not a `var`... |
| const noNextLineToken = nextToken.loc.start.line > nextLineNum; |
| const hasNextLineComment = (typeof commentEndLine[nextLineNum] !== "undefined"); |
| |
| if (mode === "never" && noNextLineToken && !hasNextLineComment) { |
| context.report({ |
| node, |
| messageId: "unexpected", |
| data: { identifier: node.name }, |
| fix(fixer) { |
| const linesBetween = sourceCode.getText().slice(lastToken.range[1], nextToken.range[0]).split(astUtils.LINEBREAK_MATCHER); |
| |
| return fixer.replaceTextRange([lastToken.range[1], nextToken.range[0]], `${linesBetween.slice(0, -1).join("")}\n${linesBetween[linesBetween.length - 1]}`); |
| } |
| }); |
| } |
| |
| // Token on the next line, or comment without blank line |
| if ( |
| mode === "always" && ( |
| !noNextLineToken || |
| hasNextLineComment && !hasBlankLineAfterComment(nextToken, nextLineNum) |
| ) |
| ) { |
| context.report({ |
| node, |
| messageId: "expected", |
| data: { identifier: node.name }, |
| fix(fixer) { |
| if ((noNextLineToken ? getLastCommentLineOfBlock(nextLineNum) : lastToken.loc.end.line) === nextToken.loc.start.line) { |
| return fixer.insertTextBefore(nextToken, "\n\n"); |
| } |
| |
| return fixer.insertTextBeforeRange([nextToken.range[0] - nextToken.loc.start.column, nextToken.range[1]], "\n"); |
| } |
| }); |
| } |
| } |
| |
| //-------------------------------------------------------------------------- |
| // Public |
| //-------------------------------------------------------------------------- |
| |
| return { |
| VariableDeclaration: checkForBlankLine |
| }; |
| |
| } |
| }; |