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astHelpers.findFirst() function

Finds the first node in an AST that matches a partial node using deep partial matching. Works with both script ASTs (ESTree) and template ASTs (vue-eslint-parser).

Signature:

export declare function findFirst<M extends Matcher<namedTypes.ASTNode | AST.Node>>(ast: AST.Node | namedTypes.ASTNode, matcher: M): (AST.Node & {
    type: M['type'];
}) | null;

Parameters

Parameter	Type	Description
ast	AST.Node | namedTypes.ASTNode	The node to traverse
matcher	M	Partial object to match against (uses lodash isMatch)

Returns:

(AST.Node & { type: M['type']; }) | null

The first matching node, or null if no matching node was found

Example

// Find the first <div> in the template
const div = findFirst(sfcAST, { type: 'VElement', name: 'div' });

// Find the first console.log call in a script
const log = findFirst(scriptAST, {
  type: 'CallExpression',
  callee: {
    type: 'MemberExpression',
    object: { type: 'Identifier', name: 'console' },
    property: { type: 'Identifier', name: 'log' },
  },
});