com.intellij.psi.util.PsiTreeUtil#findSiblingBackward ( )源码实例Demo

private static ImmutableList<JSFile> jsFilesFromDtsSymbol(
    ExecutionRootPathResolver pathResolver,
    LocalFileSystem lfs,
    PsiManager psiManager,
    PsiElement dtsElement) {
  while (dtsElement != null && !(dtsElement instanceof PsiFile)) {
    PsiElement comment =
        PsiTreeUtil.findSiblingBackward(dtsElement, JSTokenTypes.END_OF_LINE_COMMENT, null);
    if (comment != null) {
      Matcher matcher = SYMBOL_GENERATED_FROM_JS_COMMENT.matcher(comment.getText());
      if (matcher.find()) {
        JSFile file = pathToJsFile(pathResolver, lfs, psiManager, matcher.group(1));
        return file != null ? ImmutableList.of(file) : ImmutableList.of();
      }
    }
    dtsElement = dtsElement.getParent();
  }
  return ImmutableList.of();
}
 

/**
 * key: !my_tag <caret>
 */
public static boolean isElementAfterYamlTag(PsiElement psiElement) {
    if (!(psiElement instanceof LeafPsiElement)) {
        return false;
    }

    // key: !my_tag <caret>\n
    if (((LeafPsiElement) psiElement).getElementType() == YAMLTokenTypes.EOL) {
        PsiElement prevElement = PsiTreeUtil.getDeepestVisibleLast(psiElement);
        if (prevElement instanceof LeafPsiElement) {
            if (((LeafPsiElement) prevElement).getElementType() == YAMLTokenTypes.TAG) {
                return ((LeafPsiElement) prevElement).getText().startsWith("!");
            }
        }
    }

    return PsiTreeUtil.findSiblingBackward(psiElement, YAMLTokenTypes.TAG, null) != null;
}
 

private boolean isInsideDefaultInitializer(PsiElement currentElement) {
  AtElementSingle parentAtElement =
      PsiTreeUtil.getParentOfType(currentElement, AtElementSingle.class);
  if (parentAtElement == null) {
    return false;
  }

  if (parentAtElement.getLastChild() != null
      && PsiTreeUtil.findSiblingBackward(
              parentAtElement.getLastChild(),
              currentElement.getNode().getElementType(),
              false,
              null)
          == currentElement) {
    // currentElement is an immediate child of a SoyAt[State|Param]Single that does not have
    // a valid default initializer Expr (due to malformed source code during typing).
    return true;
  }
  SoyExpr atDefaultInitializer = parentAtElement.getDefaultInitializerExpr();
  if (atDefaultInitializer == null) {
    // This is also the case for @inject.
    return false;
  }

  // currentElement is a child of a SoyAt[State|Param]Single's default initializer Expr.
  return PsiTreeUtil.findFirstParent(currentElement, element -> element == atDefaultInitializer)
      != null;
}