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Diffstat (limited to 'tools/node_modules/eslint/lib/rules/operator-linebreak.js')
| -rw-r--r-- | tools/node_modules/eslint/lib/rules/operator-linebreak.js | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/tools/node_modules/eslint/lib/rules/operator-linebreak.js b/tools/node_modules/eslint/lib/rules/operator-linebreak.js new file mode 100644 index 0000000000..271cbb35c1 --- /dev/null +++ b/tools/node_modules/eslint/lib/rules/operator-linebreak.js @@ -0,0 +1,252 @@ +/** + * @fileoverview Operator linebreak - enforces operator linebreak style of two types: after and before + * @author Benoît Zugmeyer + */ + +"use strict"; + +//------------------------------------------------------------------------------ +// Requirements +//------------------------------------------------------------------------------ + +const astUtils = require("../ast-utils"); + +//------------------------------------------------------------------------------ +// Rule Definition +//------------------------------------------------------------------------------ + +module.exports = { + meta: { + docs: { + description: "enforce consistent linebreak style for operators", + category: "Stylistic Issues", + recommended: false + }, + + schema: [ + { + enum: ["after", "before", "none", null] + }, + { + type: "object", + properties: { + overrides: { + type: "object", + properties: { + anyOf: { + type: "string", + enum: ["after", "before", "none", "ignore"] + } + } + } + }, + additionalProperties: false + } + ], + + fixable: "code" + }, + + create(context) { + + const usedDefaultGlobal = !context.options[0]; + const globalStyle = context.options[0] || "after"; + const options = context.options[1] || {}; + const styleOverrides = options.overrides ? Object.assign({}, options.overrides) : {}; + + if (usedDefaultGlobal && !styleOverrides["?"]) { + styleOverrides["?"] = "before"; + } + + if (usedDefaultGlobal && !styleOverrides[":"]) { + styleOverrides[":"] = "before"; + } + + const sourceCode = context.getSourceCode(); + + //-------------------------------------------------------------------------- + // Helpers + //-------------------------------------------------------------------------- + + /** + * Gets a fixer function to fix rule issues + * @param {Token} operatorToken The operator token of an expression + * @param {string} desiredStyle The style for the rule. One of 'before', 'after', 'none' + * @returns {Function} A fixer function + */ + function getFixer(operatorToken, desiredStyle) { + return fixer => { + const tokenBefore = sourceCode.getTokenBefore(operatorToken); + const tokenAfter = sourceCode.getTokenAfter(operatorToken); + const textBefore = sourceCode.text.slice(tokenBefore.range[1], operatorToken.range[0]); + const textAfter = sourceCode.text.slice(operatorToken.range[1], tokenAfter.range[0]); + const hasLinebreakBefore = !astUtils.isTokenOnSameLine(tokenBefore, operatorToken); + const hasLinebreakAfter = !astUtils.isTokenOnSameLine(operatorToken, tokenAfter); + let newTextBefore, newTextAfter; + + if (hasLinebreakBefore !== hasLinebreakAfter && desiredStyle !== "none") { + + // If there is a comment before and after the operator, don't do a fix. + if (sourceCode.getTokenBefore(operatorToken, { includeComments: true }) !== tokenBefore && + sourceCode.getTokenAfter(operatorToken, { includeComments: true }) !== tokenAfter) { + + return null; + } + + /* + * If there is only one linebreak and it's on the wrong side of the operator, swap the text before and after the operator. + * foo && + * bar + * would get fixed to + * foo + * && bar + */ + newTextBefore = textAfter; + newTextAfter = textBefore; + } else { + const LINEBREAK_REGEX = astUtils.createGlobalLinebreakMatcher(); + + // Otherwise, if no linebreak is desired and no comments interfere, replace the linebreaks with empty strings. + newTextBefore = desiredStyle === "before" || textBefore.trim() ? textBefore : textBefore.replace(LINEBREAK_REGEX, ""); + newTextAfter = desiredStyle === "after" || textAfter.trim() ? textAfter : textAfter.replace(LINEBREAK_REGEX, ""); + + // If there was no change (due to interfering comments), don't output a fix. + if (newTextBefore === textBefore && newTextAfter === textAfter) { + return null; + } + } + + if (newTextAfter === "" && tokenAfter.type === "Punctuator" && "+-".includes(operatorToken.value) && tokenAfter.value === operatorToken.value) { + + // To avoid accidentally creating a ++ or -- operator, insert a space if the operator is a +/- and the following token is a unary +/-. + newTextAfter += " "; + } + + return fixer.replaceTextRange([tokenBefore.range[1], tokenAfter.range[0]], newTextBefore + operatorToken.value + newTextAfter); + }; + } + + /** + * Checks the operator placement + * @param {ASTNode} node The node to check + * @param {ASTNode} leftSide The node that comes before the operator in `node` + * @private + * @returns {void} + */ + function validateNode(node, leftSide) { + + /* + * When the left part of a binary expression is a single expression wrapped in + * parentheses (ex: `(a) + b`), leftToken will be the last token of the expression + * and operatorToken will be the closing parenthesis. + * The leftToken should be the last closing parenthesis, and the operatorToken + * should be the token right after that. + */ + const operatorToken = sourceCode.getTokenAfter(leftSide, astUtils.isNotClosingParenToken); + const leftToken = sourceCode.getTokenBefore(operatorToken); + const rightToken = sourceCode.getTokenAfter(operatorToken); + const operator = operatorToken.value; + const operatorStyleOverride = styleOverrides[operator]; + const style = operatorStyleOverride || globalStyle; + const fix = getFixer(operatorToken, style); + + // if single line + if (astUtils.isTokenOnSameLine(leftToken, operatorToken) && + astUtils.isTokenOnSameLine(operatorToken, rightToken)) { + + // do nothing. + + } else if (operatorStyleOverride !== "ignore" && !astUtils.isTokenOnSameLine(leftToken, operatorToken) && + !astUtils.isTokenOnSameLine(operatorToken, rightToken)) { + + // lone operator + context.report({ + node, + loc: { + line: operatorToken.loc.end.line, + column: operatorToken.loc.end.column + }, + message: "Bad line breaking before and after '{{operator}}'.", + data: { + operator + }, + fix + }); + + } else if (style === "before" && astUtils.isTokenOnSameLine(leftToken, operatorToken)) { + + context.report({ + node, + loc: { + line: operatorToken.loc.end.line, + column: operatorToken.loc.end.column + }, + message: "'{{operator}}' should be placed at the beginning of the line.", + data: { + operator + }, + fix + }); + + } else if (style === "after" && astUtils.isTokenOnSameLine(operatorToken, rightToken)) { + + context.report({ + node, + loc: { + line: operatorToken.loc.end.line, + column: operatorToken.loc.end.column + }, + message: "'{{operator}}' should be placed at the end of the line.", + data: { + operator + }, + fix + }); + + } else if (style === "none") { + + context.report({ + node, + loc: { + line: operatorToken.loc.end.line, + column: operatorToken.loc.end.column + }, + message: "There should be no line break before or after '{{operator}}'.", + data: { + operator + }, + fix + }); + + } + } + + /** + * Validates a binary expression using `validateNode` + * @param {BinaryExpression|LogicalExpression|AssignmentExpression} node node to be validated + * @returns {void} + */ + function validateBinaryExpression(node) { + validateNode(node, node.left); + } + + //-------------------------------------------------------------------------- + // Public + //-------------------------------------------------------------------------- + + return { + BinaryExpression: validateBinaryExpression, + LogicalExpression: validateBinaryExpression, + AssignmentExpression: validateBinaryExpression, + VariableDeclarator(node) { + if (node.init) { + validateNode(node, node.id); + } + }, + ConditionalExpression(node) { + validateNode(node, node.test); + validateNode(node, node.consequent); + } + }; + } +}; |