632 lines
20 KiB
JavaScript
632 lines
20 KiB
JavaScript
/**
|
|
* @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
|
|
};
|
|
}
|
|
};
|