@typescript-eslint/eslint-plugin
Version:
TypeScript plugin for ESLint
98 lines • 4.44 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.needsPrecedingSemicolon = needsPrecedingSemicolon;
const utils_1 = require("@typescript-eslint/utils");
const ast_utils_1 = require("@typescript-eslint/utils/ast-utils");
// The following is adapted from `eslint`'s source code.
// https://github.com/eslint/eslint/blob/3a4eaf921543b1cd5d1df4ea9dec02fab396af2a/lib/rules/utils/ast-utils.js#L1043-L1132
// Could be export { isStartOfExpressionStatement } from 'eslint/lib/rules/utils/ast-utils'
const BREAK_OR_CONTINUE = new Set([
utils_1.AST_NODE_TYPES.BreakStatement,
utils_1.AST_NODE_TYPES.ContinueStatement,
]);
// Declaration types that must contain a string Literal node at the end.
const DECLARATIONS = new Set([
utils_1.AST_NODE_TYPES.ExportAllDeclaration,
utils_1.AST_NODE_TYPES.ExportNamedDeclaration,
utils_1.AST_NODE_TYPES.ImportDeclaration,
]);
const IDENTIFIER_OR_KEYWORD = new Set([
utils_1.AST_NODE_TYPES.Identifier,
utils_1.AST_TOKEN_TYPES.Keyword,
]);
// Keywords that can immediately precede an ExpressionStatement node, mapped to the their node types.
const NODE_TYPES_BY_KEYWORD = {
__proto__: null,
break: utils_1.AST_NODE_TYPES.BreakStatement,
continue: utils_1.AST_NODE_TYPES.ContinueStatement,
debugger: utils_1.AST_NODE_TYPES.DebuggerStatement,
do: utils_1.AST_NODE_TYPES.DoWhileStatement,
else: utils_1.AST_NODE_TYPES.IfStatement,
return: utils_1.AST_NODE_TYPES.ReturnStatement,
yield: utils_1.AST_NODE_TYPES.YieldExpression,
};
/*
* Before an opening parenthesis, postfix `++` and `--` always trigger ASI;
* the tokens `:`, `;`, `{` and `=>` don't expect a semicolon, as that would count as an empty statement.
*/
const PUNCTUATORS = new Set([':', ';', '{', '=>', '++', '--']);
/*
* Statements that can contain an `ExpressionStatement` after a closing parenthesis.
* DoWhileStatement is an exception in that it always triggers ASI after the closing parenthesis.
*/
const STATEMENTS = new Set([
utils_1.AST_NODE_TYPES.DoWhileStatement,
utils_1.AST_NODE_TYPES.ForInStatement,
utils_1.AST_NODE_TYPES.ForOfStatement,
utils_1.AST_NODE_TYPES.ForStatement,
utils_1.AST_NODE_TYPES.IfStatement,
utils_1.AST_NODE_TYPES.WhileStatement,
utils_1.AST_NODE_TYPES.WithStatement,
]);
/**
* Determines whether an opening parenthesis `(`, bracket `[` or backtick ``` ` ``` needs to be preceded by a semicolon.
* This opening parenthesis or bracket should be at the start of an `ExpressionStatement`, a `MethodDefinition` or at
* the start of the body of an `ArrowFunctionExpression`.
* @param sourceCode The source code object.
* @param node A node at the position where an opening parenthesis or bracket will be inserted.
* @returns Whether a semicolon is required before the opening parenthesis or bracket.
*/
function needsPrecedingSemicolon(sourceCode, node) {
const prevToken = sourceCode.getTokenBefore(node);
if (!prevToken ||
(prevToken.type === utils_1.AST_TOKEN_TYPES.Punctuator &&
PUNCTUATORS.has(prevToken.value))) {
return false;
}
const prevNode = sourceCode.getNodeByRangeIndex(prevToken.range[0]);
if (!prevNode) {
return false;
}
if ((0, ast_utils_1.isClosingParenToken)(prevToken)) {
return !STATEMENTS.has(prevNode.type);
}
if ((0, ast_utils_1.isClosingBraceToken)(prevToken)) {
return ((prevNode.type === utils_1.AST_NODE_TYPES.BlockStatement &&
prevNode.parent.type === utils_1.AST_NODE_TYPES.FunctionExpression &&
prevNode.parent.parent.type !== utils_1.AST_NODE_TYPES.MethodDefinition) ||
(prevNode.type === utils_1.AST_NODE_TYPES.ClassBody &&
prevNode.parent.type === utils_1.AST_NODE_TYPES.ClassExpression) ||
prevNode.type === utils_1.AST_NODE_TYPES.ObjectExpression);
}
if (!prevNode.parent) {
return false;
}
if (IDENTIFIER_OR_KEYWORD.has(prevToken.type)) {
if (BREAK_OR_CONTINUE.has(prevNode.parent.type)) {
return false;
}
const keyword = prevToken.value;
const nodeType = NODE_TYPES_BY_KEYWORD[keyword];
return prevNode.type !== nodeType;
}
if (prevToken.type === utils_1.AST_TOKEN_TYPES.String) {
return !DECLARATIONS.has(prevNode.parent.type);
}
return true;
}
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