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📄 needsPrecedingSemiColon.ts

📊 Analysis Summary

Metric	Count
🔧 Functions	1
📦 Imports	6
📊 Variables & Constants	8

📚 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.ExportNamedDeclaration,
AST_NODE_TYPES.ImportDeclaration,
])`	✗
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_TYPES | null>	const	`{
proto: null,
break: AST_NODE_TYPES.BreakStatement,
continue: AST_NODE_TYPES.ContinueStatement,
debugger: AST_NODE_TYPES.DebuggerStatement,
do: AST_NODE_TYPES.DoWhileStatement,
else: AST_NODE_TYPES.IfStatement,
return: AST_NODE_TYPES.ReturnStatement,
yield: AST_NODE_TYPES.YieldExpression,
}`	✗
PUNCTUATORS	Set<string>	const	new Set(['--', ';', ':', '{', '++', '=>'])	✗
STATEMENTS	Set<any>	const	`new Set([
AST_NODE_TYPES.DoWhileStatement,
AST_NODE_TYPES.ForInStatement,
AST_NODE_TYPES.ForOfStatement,
AST_NODE_TYPES.ForStatement,
AST_NODE_TYPES.IfStatement,
AST_NODE_TYPES.WhileStatement,
AST_NODE_TYPES.WithStatement,
])`	✗
keyword	any	const	prevToken.value	✗
nodeType	any	const	NODE_TYPES_BY_KEYWORD[keyword]	✗

---

Functions

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

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;
}

• 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.
   */
  

• Parameters:

• sourceCode: SourceCode
• node: TSESTree.Node
• Return Type: boolean
• 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

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