📄 `needsPrecedingSemiColon`¶

📊 Analysis Summary¶

Metric	Count
🔧 Functions	1
📦 Imports	6
📊 Variables & Constants	6

📚 Table of Contents¶

Imports
Variables & Constants
Functions

🛠️ File Location:¶

📂 packages/eslint-plugin/src/util/needsPrecedingSemiColon.ts

📦 Imports¶

Name	Source
`TSESTree`	`@typescript-eslint/utils`
`SourceCode`	`@typescript-eslint/utils/ts-eslint`
`AST_NODE_TYPES`	`@typescript-eslint/utils`
`AST_TOKEN_TYPES`	`@typescript-eslint/utils`
`isClosingBraceToken`	`@typescript-eslint/utils/ast-utils`
`isClosingParenToken`	`@typescript-eslint/utils/ast-utils`

Variables & Constants¶

Name	Type	Kind	Value	Exported
`BREAK_OR_CONTINUE`	`Set<any>`	const	`new Set([ AST_NODE_TYPES.BreakStatement, AST_NODE_TYPES.ContinueStatement, ])`	✗
`DECLARATIONS`	`Set<any>`	const	`new Set([ AST_NODE_TYPES.ExportAllDeclaration, AST_NODE_TYPES.ExportNamedDecl...`	✗
`IDENTIFIER_OR_KEYWORD`	`Set<any>`	const	`new Set([ AST_NODE_TYPES.Identifier, AST_TOKEN_TYPES.Keyword, ])`	✗
`NODE_TYPES_BY_KEYWORD`	`Record<string, TSESTree.AST_NODE_TYPE...`	const	`{ __proto__: null, break: AST_NODE_TYPES.BreakStatement, continue: AST_NODE_T...`	✗
`PUNCTUATORS`	`Set<string>`	const	`new Set(['--', ';', ':', '{', '++', '=>'])`	✗
`STATEMENTS`	`Set<any>`	const	`new Set([ AST_NODE_TYPES.DoWhileStatement, AST_NODE_TYPES.ForInStatement, AST...`	✗

Functions¶

`needsPrecedingSemicolon(sourceCode: SourceCode, node: TSESTree.Node): boolean`¶

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.

Parameters:

sourceCode any: The source code object.
node any: A node at the position where an opening parenthesis or bracket will be inserted.

Returns: undefined Whether a semicolon is required before the opening parenthesis or bracket.

Raw JSDoc

/**
 * 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.
 */

Calls:

sourceCode.getTokenBefore
PUNCTUATORS.has
sourceCode.getNodeByRangeIndex
isClosingParenToken (from @typescript-eslint/utils/ast-utils)
STATEMENTS.has
isClosingBraceToken (from @typescript-eslint/utils/ast-utils)
IDENTIFIER_OR_KEYWORD.has
BREAK_OR_CONTINUE.has
DECLARATIONS.has

Code

export function needsPrecedingSemicolon(
  sourceCode: SourceCode,
  node: TSESTree.Node,
): boolean {
  const prevToken = sourceCode.getTokenBefore(node);

  if (
    !prevToken ||
    (prevToken.type === AST_TOKEN_TYPES.Punctuator &&
      PUNCTUATORS.has(prevToken.value))
  ) {
    return false;
  }

  const prevNode = sourceCode.getNodeByRangeIndex(prevToken.range[0]);

  if (!prevNode) {
    return false;
  }

  if (isClosingParenToken(prevToken)) {
    return !STATEMENTS.has(prevNode.type);
  }

  if (isClosingBraceToken(prevToken)) {
    return (
      (prevNode.type === AST_NODE_TYPES.BlockStatement &&
        prevNode.parent.type === AST_NODE_TYPES.FunctionExpression &&
        prevNode.parent.parent.type !== AST_NODE_TYPES.MethodDefinition) ||
      (prevNode.type === AST_NODE_TYPES.ClassBody &&
        prevNode.parent.type === AST_NODE_TYPES.ClassExpression) ||
      prevNode.type === 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 === AST_TOKEN_TYPES.String) {
    return !DECLARATIONS.has(prevNode.parent.type);
  }

  return true;
}

Generated by Syntax Scribe

📄 needsPrecedingSemiColon¶