Java Node.getLastChild方法代码示例

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
/**
 * Determines whether the given node is code node for FOR, DO,
 * WHILE, WITH, or IF node.
 */
static boolean isControlStructureCodeBlock(Node parent, Node n) {
  switch (parent.getType()) {
    case Token.FOR:
    case Token.WHILE:
    case Token.LABEL:
    case Token.WITH:
      return parent.getLastChild() == n;
    case Token.DO:
      return parent.getFirstChild() == n;
    case Token.IF:
      return parent.getFirstChild() != n;
    case Token.TRY:
      return parent.getFirstChild() == n || parent.getLastChild() == n;
    case Token.CATCH:
      return parent.getLastChild() == n;
    case Token.SWITCH:
    case Token.CASE:
      return parent.getFirstChild() != n;
    case Token.DEFAULT:
      return true;
    default:
      Preconditions.checkState(isControlStructure(parent));
      return false;
  }
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
/**
 * If the given value is a qualified name which refers
 * a function, the function's node is returned. Otherwise,
 * {@code null} is returned.
 */
protected Node getFunctionValue(Node value) {
  String qualifiedName = value.getQualifiedName();

  if (qualifiedName == null) {
    return null;
  }

  if (!definitionMap.containsKey(qualifiedName)) {
    return null;
  }

  Node definitionParent = definitionMap.get(qualifiedName);
  Node definition = definitionParent.getLastChild();

  if (definition.getType() != Token.FUNCTION) {
    return null;
  }

  return definition;
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
@Override
public FlowScope getPreciserScopeKnowingConditionOutcome(Node condition,
    FlowScope blindScope, boolean outcome) {
  if (condition.getType() == CALL && condition.getChildCount() == 2) {
    Node callee = condition.getFirstChild();
    Node param = condition.getLastChild();
    if (callee.getType() == GETPROP && param.isQualifiedName()) {
      JSType paramType =  getTypeIfRefinable(param, blindScope);
      Node left = callee.getFirstChild();
      Node right = callee.getLastChild();
      if (left.getType() == NAME && "goog".equals(left.getString()) &&
          right.getType() == STRING) {
        Function<TypeRestriction, JSType> restricter =
            restricters.get(right.getString());
        if (restricter != null) {
          return restrictParameter(param, paramType, blindScope, restricter,
              outcome);
        }
      }
    }
  }
  return nextPreciserScopeKnowingConditionOutcome(
      condition, blindScope, outcome);
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
/**
 * Rewrites method definitions as global functions that take "this"
 * as their first argument.
 *
 * Before:
 *   a.prototype.b = function(a, b, c) {...}
 *
 * After:
 *   var b = function(self, a, b, c) {...}
 */
private void rewriteDefinition(Node node, String newMethodName) {
  Node parent = node.getParent();
  Node functionNode = parent.getLastChild();
  Node expr = parent.getParent();
  Node block = expr.getParent();

  Node newNameNode = Node.newString(Token.NAME, newMethodName);
  parent.removeChild(functionNode);
  newNameNode.addChildToFront(functionNode);
  block.replaceChild(expr, new Node(Token.VAR, newNameNode));

  // add extra argument
  String self = newMethodName + "$self";
  Node argList = functionNode.getFirstChild().getNext();
  argList.addChildToFront(Node.newString(Token.NAME, self));

  // rewrite body
  Node body = functionNode.getLastChild();
  replaceReferencesToThis(body, self);

  // fix type
  fixFunctionType(functionNode);

  compiler.reportCodeChange();
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
/**
 * Gets the maximum number of arguments that this function requires,
 * or Integer.MAX_VALUE if this is a variable argument function.
 */
public int getMaxArguments() {
  Node params = getParametersNode();
  if (params != null) {
    Node lastParam = params.getLastChild();
    if (lastParam == null || !lastParam.isVarArgs()) {
      return params.getChildCount();
    }
  }

  return Integer.MAX_VALUE;
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
/**
 * @param n The node to inspect.
 * @return If the node, is a FOR, WHILE, or DO, it returns the node for
 * the code BLOCK, null otherwise.
 */
static Node getLoopCodeBlock(Node n) {
  switch (n.getType()) {
    case Token.FOR:
    case Token.WHILE:
      return n.getLastChild();
    case Token.DO:
      return n.getFirstChild();
    default:
      return null;
  }
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
/**
 * Try to remove duplicate statements from IF blocks. For example:
 *
 * if (a) {
 *   x = 1;
 *   return true;
 * } else {
 *   x = 2;
 *   return true;
 * }
 *
 * becomes:
 *
 * if (a) {
 *   x = 1;
 * } else {
 *   x = 2;
 * }
 * return true;
 *
 * @param n The IF node to examine.
 */
private void tryRemoveRepeatedStatements(NodeTraversal t, Node n) {
  Preconditions.checkState(n.getType() == Token.IF);

  Node parent = n.getParent();
  if (!NodeUtil.isStatementBlock(parent)) {
    // If the immediate parent is something like a label, we
    // can't move the statement, so bail.
    return;
  }

  Node cond = n.getFirstChild();
  Node trueBranch = cond.getNext();
  Node falseBranch = trueBranch.getNext();
  Preconditions.checkNotNull(trueBranch);
  Preconditions.checkNotNull(falseBranch);

  while (true) {
    Node lastTrue = trueBranch.getLastChild();
    Node lastFalse = falseBranch.getLastChild();
    if (lastTrue == null || lastFalse == null
        || !compiler.areNodesEqualForInlining(lastTrue, lastFalse)) {
      break;
    }
    lastTrue.detachFromParent();
    lastFalse.detachFromParent();
    parent.addChildAfter(lastTrue, n);
    t.getCompiler().reportCodeChange();
  }
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
/** Safely remove children while maintaining a valid node structure. */
static void removeChild(Node parent, Node node) {
  // Node parent = node.getParent();
  if (isStatementBlock(parent)
      || isSwitchCase(node)
      || isTryFinallyNode(parent, node)) {
    // A statement in a block can simply be removed.
    parent.removeChild(node);
  } else if (parent.getType() == Token.VAR) {
    if (parent.hasMoreThanOneChild()) {
      parent.removeChild(node);
    } else {
      // Remove the node from the parent, so it can be reused.
      parent.removeChild(node);
      // This would leave an empty VAR, remove the VAR itself.
      removeChild(parent.getParent(), parent);
    }
  } else if (node.getType() == Token.BLOCK) {
    // Simply empty the block.  This maintains source location and
    // "synthetic"-ness.
    node.detachChildren();
  } else if (parent.getType() == Token.LABEL
      && node == parent.getLastChild()) {
    // Remove the node from the parent, so it can be reused.
    parent.removeChild(node);
    // A LABEL without children can not be referred to, remove it.
    removeChild(parent.getParent(), parent);
  } else if (parent.getType() == Token.FOR
      && parent.getChildCount() == 4) {
    // Only Token.FOR can have an Token.EMPTY other control structure
    // need something for the condition. Others need to be replaced
    // or the structure removed.
    parent.replaceChild(node, new Node(Token.EMPTY));
  } else {
    throw new IllegalStateException("Invalid attempt to remove node: " +
        node.toString() + " of "+ parent.toString());
  }
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
/**
 * Traverses a function, which creates a new scope in javascript.
 *
 * Note that CATCH blocks also create a new scope, but only for the
 * catch variable. Declarations within the block actually belong to the
 * enclosing scope. Because we don't remove catch variables, there's
 * no need to treat CATCH blocks differently like we do functions.
 */
private void traverseFunction(Node n, Scope scope) {
  Preconditions.checkState(n.getChildCount() == 3);
  Preconditions.checkState(n.getType() == Token.FUNCTION);

  final Node body = n.getLastChild();
  Preconditions.checkState(body.getNext() == null &&
          body.getType() == Token.BLOCK);

  Scope fnScope = new SyntacticScopeCreator(compiler_).createScope(n, scope);
  traverseNode(body, n, fnScope);

  removeUnreferencedFunctionArgs(n, fnScope);
  removeUnreferencedVars(fnScope);
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
public void visit(NodeTraversal t, Node n, Node parent) {
  if (n.getType() != Token.NEW) {
    return;
  }

  Node objectName = n.getFirstChild();

  if (!ObjectPropertyStringPreprocess.EXTERN_OBJECT_PROPERTY_STRING.equals(
          objectName.getQualifiedName())) {
    return;
  }

  Node firstArgument = objectName.getNext();
  Node secondArgument = firstArgument.getNext();
  int secondArgumentType = secondArgument.getType();
  if (secondArgumentType == Token.GETPROP) {
    // Rewrite "new goog.testing.ObjectPropertyString(window, foo.bar)"
    // as "new goog.testing.ObjectPropertyString(foo, 'bar')".
    Node newChild = secondArgument.getFirstChild();
    secondArgument.removeChild(newChild);
    n.replaceChild(firstArgument, newChild);
    n.replaceChild(secondArgument,
        Node.newString(secondArgument.getFirstChild().getString()));
  } else if (secondArgumentType == Token.GETELEM) {
    // Rewrite "new goog.testing.ObjectPropertyString(window, foo[bar])"
    // as "new goog.testing.ObjectPropertyString(foo, bar)".
    Node newFirstArgument = secondArgument.getFirstChild();
    secondArgument.removeChild(newFirstArgument);
    Node newSecondArgument = secondArgument.getLastChild();
    secondArgument.removeChild(newSecondArgument);
    n.replaceChild(firstArgument, newFirstArgument);
    n.replaceChild(secondArgument, newSecondArgument);
  } else {
    // Rewrite "new goog.testing.ObjectPropertyString(window, foo)" as
    // "new goog.testing.ObjectPropertyString(window, 'foo')"
    n.replaceChild(secondArgument,
        Node.newString(secondArgument.getString()));
  }
  compiler.reportCodeChange();
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
public void testMergeBlock2() {
  Compiler compiler = new Compiler();

  // Test removing the initializer.
  Node actual = parse("foo:{a();}");

  Node parentLabel = actual.getFirstChild();
  Node childBlock = parentLabel.getLastChild();

  assertTrue(NodeUtil.tryMergeBlock(childBlock));
  String expected = "foo:a();";
  String difference = parse(expected).checkTreeEquals(actual);
  assertNull("Nodes do not match:\n" + difference, difference);
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
public void visit(NodeTraversal t, Node n, Node parent) {
  if (n.getType() == Token.ASSIGN) {
    Node nameNode = n.getFirstChild();
    Node valueNode = n.getLastChild();

    if (nameNode.isQualifiedName() &&
        valueNode.isQualifiedName() &&
        ABSTRACT_METHOD_NAME.equals(valueNode.getQualifiedName())) {
      abstractMethodAssignmentNodes.add(new RemovableAssignment(
          n.getFirstChild(), n, t));
    }
  }
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
/**
 * @return function return value node if function body contains a
 * single return statement.  Otherwise, null.
 */
protected final Node maybeGetSingleReturnRValue(Node functionNode) {
  Node body = functionNode.getLastChild();
  if (!body.hasOneChild()) {
    return null;
  }

  Node statement = body.getFirstChild();
  if (statement.getType() == Token.RETURN) {
    return statement.getFirstChild();
  }
  return null;
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
@Override
public void enterScope(NodeTraversal t) {
  Node declarationRoot = t.getScopeRoot();
  Renamer renamer;
  if (nameStack.isEmpty()) {
    // If the contextual renamer is being used the starting context can not
    // be a function.
    Preconditions.checkState(
        declarationRoot.getType() != Token.FUNCTION ||
        !(rootRenamer instanceof ContextualRenamer));
    Preconditions.checkState(t.inGlobalScope());
    renamer = rootRenamer;
  } else {
    renamer = nameStack.peek().forChildScope();
  }

  if (declarationRoot.getType() == Token.FUNCTION) {
    // Add the function parameters
    Node fnParams = declarationRoot.getFirstChild().getNext();
    for (Node c = fnParams.getFirstChild(); c != null; c = c.getNext()) {
      String name = c.getString();
      renamer.addDeclaredName(name);
    }

    // Add the function body declarations
    Node functionBody = declarationRoot.getLastChild();
    findDeclaredNames(functionBody, null, renamer);
  } else {
    // Add the block declarations
    findDeclaredNames(declarationRoot, null, renamer);
  }
  nameStack.push(renamer);
}
 

import com.google.javascript.rhino.Node; //导入方法依赖的package包/类
public void testCommentPositions() {
  Node root = newParse("/** @param {string} x */function a(x) {};" +
      "/** @param {string} x */function b(x) {}");
  Node a = root.getFirstChild();
  Node b = root.getLastChild();
  assertMarkerPosition(a, 0, 4);
  assertMarkerPosition(b, 0, 45);
}