| /** |
| * @fileoverview enforce a particular style for multiline comments |
| * @author Teddy Katz |
| */ |
| "use strict"; |
| |
| const astUtils = require("./utils/ast-utils"); |
| |
| //------------------------------------------------------------------------------ |
| // Rule Definition |
| //------------------------------------------------------------------------------ |
| |
| module.exports = { |
| meta: { |
| type: "suggestion", |
| |
| docs: { |
| description: "enforce a particular style for multiline comments", |
| category: "Stylistic Issues", |
| recommended: false, |
| url: "https://eslint.org/docs/rules/multiline-comment-style" |
| }, |
| |
| fixable: "whitespace", |
| schema: [{ enum: ["starred-block", "separate-lines", "bare-block"] }], |
| messages: { |
| expectedBlock: "Expected a block comment instead of consecutive line comments.", |
| expectedBareBlock: "Expected a block comment without padding stars.", |
| startNewline: "Expected a linebreak after '/*'.", |
| endNewline: "Expected a linebreak before '*/'.", |
| missingStar: "Expected a '*' at the start of this line.", |
| alignment: "Expected this line to be aligned with the start of the comment.", |
| expectedLines: "Expected multiple line comments instead of a block comment." |
| } |
| }, |
| |
| create(context) { |
| const sourceCode = context.getSourceCode(); |
| const option = context.options[0] || "starred-block"; |
| |
| //---------------------------------------------------------------------- |
| // Helpers |
| //---------------------------------------------------------------------- |
| |
| /** |
| * Gets a list of comment lines in a group |
| * @param {Token[]} commentGroup A group of comments, containing either multiple line comments or a single block comment |
| * @returns {string[]} A list of comment lines |
| */ |
| function getCommentLines(commentGroup) { |
| if (commentGroup[0].type === "Line") { |
| return commentGroup.map(comment => comment.value); |
| } |
| return commentGroup[0].value |
| .split(astUtils.LINEBREAK_MATCHER) |
| .map(line => line.replace(/^\s*\*?/u, "")); |
| } |
| |
| /** |
| * Converts a comment into starred-block form |
| * @param {Token} firstComment The first comment of the group being converted |
| * @param {string[]} commentLinesList A list of lines to appear in the new starred-block comment |
| * @returns {string} A representation of the comment value in starred-block form, excluding start and end markers |
| */ |
| function convertToStarredBlock(firstComment, commentLinesList) { |
| const initialOffset = sourceCode.text.slice(firstComment.range[0] - firstComment.loc.start.column, firstComment.range[0]); |
| const starredLines = commentLinesList.map(line => `${initialOffset} *${line}`); |
| |
| return `\n${starredLines.join("\n")}\n${initialOffset} `; |
| } |
| |
| /** |
| * Converts a comment into separate-line form |
| * @param {Token} firstComment The first comment of the group being converted |
| * @param {string[]} commentLinesList A list of lines to appear in the new starred-block comment |
| * @returns {string} A representation of the comment value in separate-line form |
| */ |
| function convertToSeparateLines(firstComment, commentLinesList) { |
| const initialOffset = sourceCode.text.slice(firstComment.range[0] - firstComment.loc.start.column, firstComment.range[0]); |
| const separateLines = commentLinesList.map(line => `// ${line.trim()}`); |
| |
| return separateLines.join(`\n${initialOffset}`); |
| } |
| |
| /** |
| * Converts a comment into bare-block form |
| * @param {Token} firstComment The first comment of the group being converted |
| * @param {string[]} commentLinesList A list of lines to appear in the new starred-block comment |
| * @returns {string} A representation of the comment value in bare-block form |
| */ |
| function convertToBlock(firstComment, commentLinesList) { |
| const initialOffset = sourceCode.text.slice(firstComment.range[0] - firstComment.loc.start.column, firstComment.range[0]); |
| const blockLines = commentLinesList.map(line => line.trim()); |
| |
| return `/* ${blockLines.join(`\n${initialOffset} `)} */`; |
| } |
| |
| /** |
| * Check a comment is JSDoc form |
| * @param {Token[]} commentGroup A group of comments, containing either multiple line comments or a single block comment |
| * @returns {boolean} if commentGroup is JSDoc form, return true |
| */ |
| function isJSDoc(commentGroup) { |
| const lines = commentGroup[0].value.split(astUtils.LINEBREAK_MATCHER); |
| |
| return commentGroup[0].type === "Block" && |
| /^\*\s*$/u.test(lines[0]) && |
| lines.slice(1, -1).every(line => /^\s* /u.test(line)) && |
| /^\s*$/u.test(lines[lines.length - 1]); |
| } |
| |
| /** |
| * Each method checks a group of comments to see if it's valid according to the given option. |
| * @param {Token[]} commentGroup A list of comments that appear together. This will either contain a single |
| * block comment or multiple line comments. |
| * @returns {void} |
| */ |
| const commentGroupCheckers = { |
| "starred-block"(commentGroup) { |
| const commentLines = getCommentLines(commentGroup); |
| |
| if (commentLines.some(value => value.includes("*/"))) { |
| return; |
| } |
| |
| if (commentGroup.length > 1) { |
| context.report({ |
| loc: { |
| start: commentGroup[0].loc.start, |
| end: commentGroup[commentGroup.length - 1].loc.end |
| }, |
| messageId: "expectedBlock", |
| fix(fixer) { |
| const range = [commentGroup[0].range[0], commentGroup[commentGroup.length - 1].range[1]]; |
| const starredBlock = `/*${convertToStarredBlock(commentGroup[0], commentLines)}*/`; |
| |
| return commentLines.some(value => value.startsWith("/")) |
| ? null |
| : fixer.replaceTextRange(range, starredBlock); |
| } |
| }); |
| } else { |
| const block = commentGroup[0]; |
| const lines = block.value.split(astUtils.LINEBREAK_MATCHER); |
| const expectedLinePrefix = `${sourceCode.text.slice(block.range[0] - block.loc.start.column, block.range[0])} *`; |
| |
| if (!/^\*?\s*$/u.test(lines[0])) { |
| const start = block.value.startsWith("*") ? block.range[0] + 1 : block.range[0]; |
| |
| context.report({ |
| loc: { |
| start: block.loc.start, |
| end: { line: block.loc.start.line, column: block.loc.start.column + 2 } |
| }, |
| messageId: "startNewline", |
| fix: fixer => fixer.insertTextAfterRange([start, start + 2], `\n${expectedLinePrefix}`) |
| }); |
| } |
| |
| if (!/^\s*$/u.test(lines[lines.length - 1])) { |
| context.report({ |
| loc: { |
| start: { line: block.loc.end.line, column: block.loc.end.column - 2 }, |
| end: block.loc.end |
| }, |
| messageId: "endNewline", |
| fix: fixer => fixer.replaceTextRange([block.range[1] - 2, block.range[1]], `\n${expectedLinePrefix}/`) |
| }); |
| } |
| |
| for (let lineNumber = block.loc.start.line + 1; lineNumber <= block.loc.end.line; lineNumber++) { |
| const lineText = sourceCode.lines[lineNumber - 1]; |
| |
| if (!lineText.startsWith(expectedLinePrefix)) { |
| context.report({ |
| loc: { |
| start: { line: lineNumber, column: 0 }, |
| end: { line: lineNumber, column: sourceCode.lines[lineNumber - 1].length } |
| }, |
| messageId: /^\s*\*/u.test(lineText) |
| ? "alignment" |
| : "missingStar", |
| fix(fixer) { |
| const lineStartIndex = sourceCode.getIndexFromLoc({ line: lineNumber, column: 0 }); |
| const linePrefixLength = lineText.match(/^\s*\*? ?/u)[0].length; |
| const commentStartIndex = lineStartIndex + linePrefixLength; |
| |
| const replacementText = lineNumber === block.loc.end.line || lineText.length === linePrefixLength |
| ? expectedLinePrefix |
| : `${expectedLinePrefix} `; |
| |
| return fixer.replaceTextRange([lineStartIndex, commentStartIndex], replacementText); |
| } |
| }); |
| } |
| } |
| } |
| }, |
| "separate-lines"(commentGroup) { |
| if (!isJSDoc(commentGroup) && commentGroup[0].type === "Block") { |
| const commentLines = getCommentLines(commentGroup); |
| const block = commentGroup[0]; |
| const tokenAfter = sourceCode.getTokenAfter(block, { includeComments: true }); |
| |
| if (tokenAfter && block.loc.end.line === tokenAfter.loc.start.line) { |
| return; |
| } |
| |
| context.report({ |
| loc: { |
| start: block.loc.start, |
| end: { line: block.loc.start.line, column: block.loc.start.column + 2 } |
| }, |
| messageId: "expectedLines", |
| fix(fixer) { |
| return fixer.replaceText(block, convertToSeparateLines(block, commentLines.filter(line => line))); |
| } |
| }); |
| } |
| }, |
| "bare-block"(commentGroup) { |
| if (!isJSDoc(commentGroup)) { |
| const commentLines = getCommentLines(commentGroup); |
| |
| // disallows consecutive line comments in favor of using a block comment. |
| if (commentGroup[0].type === "Line" && commentLines.length > 1 && |
| !commentLines.some(value => value.includes("*/"))) { |
| context.report({ |
| loc: { |
| start: commentGroup[0].loc.start, |
| end: commentGroup[commentGroup.length - 1].loc.end |
| }, |
| messageId: "expectedBlock", |
| fix(fixer) { |
| const range = [commentGroup[0].range[0], commentGroup[commentGroup.length - 1].range[1]]; |
| const block = convertToBlock(commentGroup[0], commentLines.filter(line => line)); |
| |
| return fixer.replaceTextRange(range, block); |
| } |
| }); |
| } |
| |
| // prohibits block comments from having a * at the beginning of each line. |
| if (commentGroup[0].type === "Block") { |
| const block = commentGroup[0]; |
| const lines = block.value.split(astUtils.LINEBREAK_MATCHER).filter(line => line.trim()); |
| |
| if (lines.length > 0 && lines.every(line => /^\s*\*/u.test(line))) { |
| context.report({ |
| loc: { |
| start: block.loc.start, |
| end: { line: block.loc.start.line, column: block.loc.start.column + 2 } |
| }, |
| messageId: "expectedBareBlock", |
| fix(fixer) { |
| return fixer.replaceText(block, convertToBlock(block, commentLines.filter(line => line))); |
| } |
| }); |
| } |
| } |
| } |
| } |
| }; |
| |
| //---------------------------------------------------------------------- |
| // Public |
| //---------------------------------------------------------------------- |
| |
| return { |
| Program() { |
| return sourceCode.getAllComments() |
| .filter(comment => comment.type !== "Shebang") |
| .filter(comment => !astUtils.COMMENTS_IGNORE_PATTERN.test(comment.value)) |
| .filter(comment => { |
| const tokenBefore = sourceCode.getTokenBefore(comment, { includeComments: true }); |
| |
| return !tokenBefore || tokenBefore.loc.end.line < comment.loc.start.line; |
| }) |
| .reduce((commentGroups, comment, index, commentList) => { |
| const tokenBefore = sourceCode.getTokenBefore(comment, { includeComments: true }); |
| |
| if ( |
| comment.type === "Line" && |
| index && commentList[index - 1].type === "Line" && |
| tokenBefore && tokenBefore.loc.end.line === comment.loc.start.line - 1 && |
| tokenBefore === commentList[index - 1] |
| ) { |
| commentGroups[commentGroups.length - 1].push(comment); |
| } else { |
| commentGroups.push([comment]); |
| } |
| |
| return commentGroups; |
| }, []) |
| .filter(commentGroup => !(commentGroup.length === 1 && commentGroup[0].loc.start.line === commentGroup[0].loc.end.line)) |
| .forEach(commentGroupCheckers[option]); |
| } |
| }; |
| } |
| }; |
