Function tryPatternMatch

src/util/nodeFinders.ts:146–187

(
  node: SyntaxNode,
  patterns: Pattern[]
)

}

function tryPatternMatch(
  node: SyntaxNode,
  patterns: Pattern[]
): SyntaxNode | null {
  const firstPattern = patterns[0];
  const lastPattern = patterns[patterns.length - 1];
  let resultNode: SyntaxNode | null = null;
  let resultPattern;
  // Only one type try to match current node.
  if (patterns.length === 1) {
    if (firstPattern.typeEquals(node)) {
      resultNode = node;
      resultPattern = firstPattern;
    }
  } else {
    // Matched last. Ascending search.
    if (lastPattern.typeEquals(node)) {
      const result = searchNodeAscending(node, lastPattern, patterns);
      if (result != null) {
        [resultNode, resultPattern] = result;
      }
    }
    // Matched first. Descending search.
    if (resultNode == null && firstPattern.typeEquals(node)) {
      const result = searchNodeDescending(node, firstPattern, patterns);
      if (result != null) {
        [resultNode, resultPattern] = result;
      }
    }
  }
  // Use field name child if field name is given
  if (
    resultNode != null &&
    resultPattern != null &&
    resultPattern.fields != null
  ) {
    resultPattern.fields.forEach((field) => {
      resultNode = resultNode?.childForFieldName(field) ?? null;
    });
  }
  return resultNode;
}

type NodePattern = [SyntaxNode, Pattern] | null;