first commit

app_vue/node_modules/eslint/lib/rules/padding-line-between-statements.js

@@ -0,0 +1,632 @@
+/**
+ * @fileoverview Rule to require or disallow newlines between statements
+ * @author Toru Nagashima
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const astUtils = require("./utils/ast-utils");
+
+//------------------------------------------------------------------------------
+// Helpers
+//------------------------------------------------------------------------------
+
+const LT = `[${Array.from(astUtils.LINEBREAKS).join("")}]`;
+const PADDING_LINE_SEQUENCE = new RegExp(
+    String.raw`^(\s*?${LT})\s*${LT}(\s*;?)$`,
+    "u"
+);
+const CJS_EXPORT = /^(?:module\s*\.\s*)?exports(?:\s*\.|\s*\[|$)/u;
+const CJS_IMPORT = /^require\(/u;
+
+/**
+ * Creates tester which check if a node starts with specific keyword.
+ * @param {string} keyword The keyword to test.
+ * @returns {Object} the created tester.
+ * @private
+ */
+function newKeywordTester(keyword) {
+    return {
+        test: (node, sourceCode) =>
+            sourceCode.getFirstToken(node).value === keyword
+    };
+}
+
+/**
+ * Creates tester which check if a node starts with specific keyword and spans a single line.
+ * @param {string} keyword The keyword to test.
+ * @returns {Object} the created tester.
+ * @private
+ */
+function newSinglelineKeywordTester(keyword) {
+    return {
+        test: (node, sourceCode) =>
+            node.loc.start.line === node.loc.end.line &&
+            sourceCode.getFirstToken(node).value === keyword
+    };
+}
+
+/**
+ * Creates tester which check if a node starts with specific keyword and spans multiple lines.
+ * @param {string} keyword The keyword to test.
+ * @returns {Object} the created tester.
+ * @private
+ */
+function newMultilineKeywordTester(keyword) {
+    return {
+        test: (node, sourceCode) =>
+            node.loc.start.line !== node.loc.end.line &&
+            sourceCode.getFirstToken(node).value === keyword
+    };
+}
+
+/**
+ * Creates tester which check if a node is specific type.
+ * @param {string} type The node type to test.
+ * @returns {Object} the created tester.
+ * @private
+ */
+function newNodeTypeTester(type) {
+    return {
+        test: node =>
+            node.type === type
+    };
+}
+
+/**
+ * Checks the given node is an expression statement of IIFE.
+ * @param {ASTNode} node The node to check.
+ * @returns {boolean} `true` if the node is an expression statement of IIFE.
+ * @private
+ */
+function isIIFEStatement(node) {
+    if (node.type === "ExpressionStatement") {
+        let call = astUtils.skipChainExpression(node.expression);
+
+        if (call.type === "UnaryExpression") {
+            call = astUtils.skipChainExpression(call.argument);
+        }
+        return call.type === "CallExpression" && astUtils.isFunction(call.callee);
+    }
+    return false;
+}
+
+/**
+ * Checks whether the given node is a block-like statement.
+ * This checks the last token of the node is the closing brace of a block.
+ * @param {SourceCode} sourceCode The source code to get tokens.
+ * @param {ASTNode} node The node to check.
+ * @returns {boolean} `true` if the node is a block-like statement.
+ * @private
+ */
+function isBlockLikeStatement(sourceCode, node) {
+
+    // do-while with a block is a block-like statement.
+    if (node.type === "DoWhileStatement" && node.body.type === "BlockStatement") {
+        return true;
+    }
+
+    /*
+     * IIFE is a block-like statement specially from
+     * JSCS#disallowPaddingNewLinesAfterBlocks.
+     */
+    if (isIIFEStatement(node)) {
+        return true;
+    }
+
+    // Checks the last token is a closing brace of blocks.
+    const lastToken = sourceCode.getLastToken(node, astUtils.isNotSemicolonToken);
+    const belongingNode = lastToken && astUtils.isClosingBraceToken(lastToken)
+        ? sourceCode.getNodeByRangeIndex(lastToken.range[0])
+        : null;
+
+    return Boolean(belongingNode) && (
+        belongingNode.type === "BlockStatement" ||
+        belongingNode.type === "SwitchStatement"
+    );
+}
+
+/**
+ * Check whether the given node is a directive or not.
+ * @param {ASTNode} node The node to check.
+ * @param {SourceCode} sourceCode The source code object to get tokens.
+ * @returns {boolean} `true` if the node is a directive.
+ */
+function isDirective(node, sourceCode) {
+    return (
+        node.type === "ExpressionStatement" &&
+        (
+            node.parent.type === "Program" ||
+            (
+                node.parent.type === "BlockStatement" &&
+                astUtils.isFunction(node.parent.parent)
+            )
+        ) &&
+        node.expression.type === "Literal" &&
+        typeof node.expression.value === "string" &&
+        !astUtils.isParenthesised(sourceCode, node.expression)
+    );
+}
+
+/**
+ * Check whether the given node is a part of directive prologue or not.
+ * @param {ASTNode} node The node to check.
+ * @param {SourceCode} sourceCode The source code object to get tokens.
+ * @returns {boolean} `true` if the node is a part of directive prologue.
+ */
+function isDirectivePrologue(node, sourceCode) {
+    if (isDirective(node, sourceCode)) {
+        for (const sibling of node.parent.body) {
+            if (sibling === node) {
+                break;
+            }
+            if (!isDirective(sibling, sourceCode)) {
+                return false;
+            }
+        }
+        return true;
+    }
+    return false;
+}
+
+/**
+ * Gets the actual last token.
+ *
+ * If a semicolon is semicolon-less style's semicolon, this ignores it.
+ * For example:
+ *
+ *     foo()
+ *     ;[1, 2, 3].forEach(bar)
+ * @param {SourceCode} sourceCode The source code to get tokens.
+ * @param {ASTNode} node The node to get.
+ * @returns {Token} The actual last token.
+ * @private
+ */
+function getActualLastToken(sourceCode, node) {
+    const semiToken = sourceCode.getLastToken(node);
+    const prevToken = sourceCode.getTokenBefore(semiToken);
+    const nextToken = sourceCode.getTokenAfter(semiToken);
+    const isSemicolonLessStyle = Boolean(
+        prevToken &&
+        nextToken &&
+        prevToken.range[0] >= node.range[0] &&
+        astUtils.isSemicolonToken(semiToken) &&
+        semiToken.loc.start.line !== prevToken.loc.end.line &&
+        semiToken.loc.end.line === nextToken.loc.start.line
+    );
+
+    return isSemicolonLessStyle ? prevToken : semiToken;
+}
+
+/**
+ * This returns the concatenation of the first 2 captured strings.
+ * @param {string} _ Unused. Whole matched string.
+ * @param {string} trailingSpaces The trailing spaces of the first line.
+ * @param {string} indentSpaces The indentation spaces of the last line.
+ * @returns {string} The concatenation of trailingSpaces and indentSpaces.
+ * @private
+ */
+function replacerToRemovePaddingLines(_, trailingSpaces, indentSpaces) {
+    return trailingSpaces + indentSpaces;
+}
+
+/**
+ * Check and report statements for `any` configuration.
+ * It does nothing.
+ * @returns {void}
+ * @private
+ */
+function verifyForAny() {
+}
+
+/**
+ * Check and report statements for `never` configuration.
+ * This autofix removes blank lines between the given 2 statements.
+ * However, if comments exist between 2 blank lines, it does not remove those
+ * blank lines automatically.
+ * @param {RuleContext} context The rule context to report.
+ * @param {ASTNode} _ Unused. The previous node to check.
+ * @param {ASTNode} nextNode The next node to check.
+ * @param {Array<Token[]>} paddingLines The array of token pairs that blank
+ * lines exist between the pair.
+ * @returns {void}
+ * @private
+ */
+function verifyForNever(context, _, nextNode, paddingLines) {
+    if (paddingLines.length === 0) {
+        return;
+    }
+
+    context.report({
+        node: nextNode,
+        messageId: "unexpectedBlankLine",
+        fix(fixer) {
+            if (paddingLines.length >= 2) {
+                return null;
+            }
+
+            const prevToken = paddingLines[0][0];
+            const nextToken = paddingLines[0][1];
+            const start = prevToken.range[1];
+            const end = nextToken.range[0];
+            const text = context.getSourceCode().text
+                .slice(start, end)
+                .replace(PADDING_LINE_SEQUENCE, replacerToRemovePaddingLines);
+
+            return fixer.replaceTextRange([start, end], text);
+        }
+    });
+}
+
+/**
+ * Check and report statements for `always` configuration.
+ * This autofix inserts a blank line between the given 2 statements.
+ * If the `prevNode` has trailing comments, it inserts a blank line after the
+ * trailing comments.
+ * @param {RuleContext} context The rule context to report.
+ * @param {ASTNode} prevNode The previous node to check.
+ * @param {ASTNode} nextNode The next node to check.
+ * @param {Array<Token[]>} paddingLines The array of token pairs that blank
+ * lines exist between the pair.
+ * @returns {void}
+ * @private
+ */
+function verifyForAlways(context, prevNode, nextNode, paddingLines) {
+    if (paddingLines.length > 0) {
+        return;
+    }
+
+    context.report({
+        node: nextNode,
+        messageId: "expectedBlankLine",
+        fix(fixer) {
+            const sourceCode = context.getSourceCode();
+            let prevToken = getActualLastToken(sourceCode, prevNode);
+            const nextToken = sourceCode.getFirstTokenBetween(
+                prevToken,
+                nextNode,
+                {
+                    includeComments: true,
+
+                    /**
+                     * Skip the trailing comments of the previous node.
+                     * This inserts a blank line after the last trailing comment.
+                     *
+                     * For example:
+                     *
+                     *     foo(); // trailing comment.
+                     *     // comment.
+                     *     bar();
+                     *
+                     * Get fixed to:
+                     *
+                     *     foo(); // trailing comment.
+                     *
+                     *     // comment.
+                     *     bar();
+                     * @param {Token} token The token to check.
+                     * @returns {boolean} `true` if the token is not a trailing comment.
+                     * @private
+                     */
+                    filter(token) {
+                        if (astUtils.isTokenOnSameLine(prevToken, token)) {
+                            prevToken = token;
+                            return false;
+                        }
+                        return true;
+                    }
+                }
+            ) || nextNode;
+            const insertText = astUtils.isTokenOnSameLine(prevToken, nextToken)
+                ? "\n\n"
+                : "\n";
+
+            return fixer.insertTextAfter(prevToken, insertText);
+        }
+    });
+}
+
+/**
+ * Types of blank lines.
+ * `any`, `never`, and `always` are defined.
+ * Those have `verify` method to check and report statements.
+ * @private
+ */
+const PaddingTypes = {
+    any: { verify: verifyForAny },
+    never: { verify: verifyForNever },
+    always: { verify: verifyForAlways }
+};
+
+/**
+ * Types of statements.
+ * Those have `test` method to check it matches to the given statement.
+ * @private
+ */
+const StatementTypes = {
+    "*": { test: () => true },
+    "block-like": {
+        test: (node, sourceCode) => isBlockLikeStatement(sourceCode, node)
+    },
+    "cjs-export": {
+        test: (node, sourceCode) =>
+            node.type === "ExpressionStatement" &&
+            node.expression.type === "AssignmentExpression" &&
+            CJS_EXPORT.test(sourceCode.getText(node.expression.left))
+    },
+    "cjs-import": {
+        test: (node, sourceCode) =>
+            node.type === "VariableDeclaration" &&
+            node.declarations.length > 0 &&
+            Boolean(node.declarations[0].init) &&
+            CJS_IMPORT.test(sourceCode.getText(node.declarations[0].init))
+    },
+    directive: {
+        test: isDirectivePrologue
+    },
+    expression: {
+        test: (node, sourceCode) =>
+            node.type === "ExpressionStatement" &&
+            !isDirectivePrologue(node, sourceCode)
+    },
+    iife: {
+        test: isIIFEStatement
+    },
+    "multiline-block-like": {
+        test: (node, sourceCode) =>
+            node.loc.start.line !== node.loc.end.line &&
+            isBlockLikeStatement(sourceCode, node)
+    },
+    "multiline-expression": {
+        test: (node, sourceCode) =>
+            node.loc.start.line !== node.loc.end.line &&
+            node.type === "ExpressionStatement" &&
+            !isDirectivePrologue(node, sourceCode)
+    },
+
+    "multiline-const": newMultilineKeywordTester("const"),
+    "multiline-let": newMultilineKeywordTester("let"),
+    "multiline-var": newMultilineKeywordTester("var"),
+    "singleline-const": newSinglelineKeywordTester("const"),
+    "singleline-let": newSinglelineKeywordTester("let"),
+    "singleline-var": newSinglelineKeywordTester("var"),
+
+    block: newNodeTypeTester("BlockStatement"),
+    empty: newNodeTypeTester("EmptyStatement"),
+    function: newNodeTypeTester("FunctionDeclaration"),
+
+    break: newKeywordTester("break"),
+    case: newKeywordTester("case"),
+    class: newKeywordTester("class"),
+    const: newKeywordTester("const"),
+    continue: newKeywordTester("continue"),
+    debugger: newKeywordTester("debugger"),
+    default: newKeywordTester("default"),
+    do: newKeywordTester("do"),
+    export: newKeywordTester("export"),
+    for: newKeywordTester("for"),
+    if: newKeywordTester("if"),
+    import: newKeywordTester("import"),
+    let: newKeywordTester("let"),
+    return: newKeywordTester("return"),
+    switch: newKeywordTester("switch"),
+    throw: newKeywordTester("throw"),
+    try: newKeywordTester("try"),
+    var: newKeywordTester("var"),
+    while: newKeywordTester("while"),
+    with: newKeywordTester("with")
+};
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = {
+    meta: {
+        type: "layout",
+
+        docs: {
+            description: "require or disallow padding lines between statements",
+            category: "Stylistic Issues",
+            recommended: false,
+            url: "https://eslint.org/docs/rules/padding-line-between-statements"
+        },
+
+        fixable: "whitespace",
+
+        schema: {
+            definitions: {
+                paddingType: {
+                    enum: Object.keys(PaddingTypes)
+                },
+                statementType: {
+                    anyOf: [
+                        { enum: Object.keys(StatementTypes) },
+                        {
+                            type: "array",
+                            items: { enum: Object.keys(StatementTypes) },
+                            minItems: 1,
+                            uniqueItems: true,
+                            additionalItems: false
+                        }
+                    ]
+                }
+            },
+            type: "array",
+            items: {
+                type: "object",
+                properties: {
+                    blankLine: { $ref: "#/definitions/paddingType" },
+                    prev: { $ref: "#/definitions/statementType" },
+                    next: { $ref: "#/definitions/statementType" }
+                },
+                additionalProperties: false,
+                required: ["blankLine", "prev", "next"]
+            },
+            additionalItems: false
+        },
+
+        messages: {
+            unexpectedBlankLine: "Unexpected blank line before this statement.",
+            expectedBlankLine: "Expected blank line before this statement."
+        }
+    },
+
+    create(context) {
+        const sourceCode = context.getSourceCode();
+        const configureList = context.options || [];
+        let scopeInfo = null;
+
+        /**
+         * Processes to enter to new scope.
+         * This manages the current previous statement.
+         * @returns {void}
+         * @private
+         */
+        function enterScope() {
+            scopeInfo = {
+                upper: scopeInfo,
+                prevNode: null
+            };
+        }
+
+        /**
+         * Processes to exit from the current scope.
+         * @returns {void}
+         * @private
+         */
+        function exitScope() {
+            scopeInfo = scopeInfo.upper;
+        }
+
+        /**
+         * Checks whether the given node matches the given type.
+         * @param {ASTNode} node The statement node to check.
+         * @param {string|string[]} type The statement type to check.
+         * @returns {boolean} `true` if the statement node matched the type.
+         * @private
+         */
+        function match(node, type) {
+            let innerStatementNode = node;
+
+            while (innerStatementNode.type === "LabeledStatement") {
+                innerStatementNode = innerStatementNode.body;
+            }
+            if (Array.isArray(type)) {
+                return type.some(match.bind(null, innerStatementNode));
+            }
+            return StatementTypes[type].test(innerStatementNode, sourceCode);
+        }
+
+        /**
+         * Finds the last matched configure from configureList.
+         * @param {ASTNode} prevNode The previous statement to match.
+         * @param {ASTNode} nextNode The current statement to match.
+         * @returns {Object} The tester of the last matched configure.
+         * @private
+         */
+        function getPaddingType(prevNode, nextNode) {
+            for (let i = configureList.length - 1; i >= 0; --i) {
+                const configure = configureList[i];
+                const matched =
+                    match(prevNode, configure.prev) &&
+                    match(nextNode, configure.next);
+
+                if (matched) {
+                    return PaddingTypes[configure.blankLine];
+                }
+            }
+            return PaddingTypes.any;
+        }
+
+        /**
+         * Gets padding line sequences between the given 2 statements.
+         * Comments are separators of the padding line sequences.
+         * @param {ASTNode} prevNode The previous statement to count.
+         * @param {ASTNode} nextNode The current statement to count.
+         * @returns {Array<Token[]>} The array of token pairs.
+         * @private
+         */
+        function getPaddingLineSequences(prevNode, nextNode) {
+            const pairs = [];
+            let prevToken = getActualLastToken(sourceCode, prevNode);
+
+            if (nextNode.loc.start.line - prevToken.loc.end.line >= 2) {
+                do {
+                    const token = sourceCode.getTokenAfter(
+                        prevToken,
+                        { includeComments: true }
+                    );
+
+                    if (token.loc.start.line - prevToken.loc.end.line >= 2) {
+                        pairs.push([prevToken, token]);
+                    }
+                    prevToken = token;
+
+                } while (prevToken.range[0] < nextNode.range[0]);
+            }
+
+            return pairs;
+        }
+
+        /**
+         * Verify padding lines between the given node and the previous node.
+         * @param {ASTNode} node The node to verify.
+         * @returns {void}
+         * @private
+         */
+        function verify(node) {
+            const parentType = node.parent.type;
+            const validParent =
+                astUtils.STATEMENT_LIST_PARENTS.has(parentType) ||
+                parentType === "SwitchStatement";
+
+            if (!validParent) {
+                return;
+            }
+
+            // Save this node as the current previous statement.
+            const prevNode = scopeInfo.prevNode;
+
+            // Verify.
+            if (prevNode) {
+                const type = getPaddingType(prevNode, node);
+                const paddingLines = getPaddingLineSequences(prevNode, node);
+
+                type.verify(context, prevNode, node, paddingLines);
+            }
+
+            scopeInfo.prevNode = node;
+        }
+
+        /**
+         * Verify padding lines between the given node and the previous node.
+         * Then process to enter to new scope.
+         * @param {ASTNode} node The node to verify.
+         * @returns {void}
+         * @private
+         */
+        function verifyThenEnterScope(node) {
+            verify(node);
+            enterScope();
+        }
+
+        return {
+            Program: enterScope,
+            BlockStatement: enterScope,
+            SwitchStatement: enterScope,
+            "Program:exit": exitScope,
+            "BlockStatement:exit": exitScope,
+            "SwitchStatement:exit": exitScope,
+
+            ":statement": verify,
+
+            SwitchCase: verifyThenEnterScope,
+            "SwitchCase:exit": exitScope
+        };
+    }
+};