Java Code Examples for com.google.javascript.rhino.Node#isCall()

private void addSimplifiedExpression(Node n, Node parent) {
  if (parent.isVar()) {
    Node value = n.getFirstChild();
    if (value != null) {
      addSimplifiedChildren(value);
    }
  } else if (n.isAssign() &&
      (parent.isExprResult() ||
       parent.isFor() ||
       parent.isReturn())) {
    for (Node child : n.children()) {
      addSimplifiedChildren(child);
    }
  } else if (n.isCall() &&
             parent.isExprResult()) {
    addSimplifiedChildren(n);
  } else {
    addAllChildren(n);
  }
}
 

private void addSimplifiedExpression(Node n, Node parent) {
  if (parent.isVar()) {
    Node value = n.getFirstChild();
    if (value != null) {
      addSimplifiedChildren(value);
    }
  } else if (n.isAssign() &&
      (parent.isExprResult() ||
       parent.isFor() ||
       parent.isReturn())) {
    for (Node child : n.children()) {
      addSimplifiedChildren(child);
    }
  } else if (n.isCall() &&
             parent.isExprResult()) {
    addSimplifiedChildren(n);
  } else {
    addAllChildren(n);
  }
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  if (n.isCall()) {
    Node target = n.getFirstChild();
    // TODO(johnlenz): add this to the coding convention
    // so we can remove goog.reflect.sinkValue as well.
    if (target.isName() && target.getString().equals(PROTECTOR_FN)) {
      Node expr = n.getLastChild();
      n.detachChildren();
      parent.replaceChild(n, expr);
    }
  }
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  if (n.isCall()) {
    Node target = n.getFirstChild();
    // TODO(johnlenz): add this to the coding convention
    // so we can remove goog.reflect.sinkValue as well.
    if (target.isName() && target.getString().equals(PROTECTOR_FN)) {
      Node expr = n.getLastChild();
      n.detachChildren();
      parent.replaceChild(n, expr);
    }
  }
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  if (n.isCall()) {
    Node target = n.getFirstChild();
    // TODO(johnlenz): add this to the coding convention
    // so we can remove goog.reflect.sinkValue as well.
    if (target.isName() && target.getString().equals(PROTECTOR_FN)) {
      Node expr = n.getLastChild();
      n.detachChildren();
      parent.replaceChild(n, expr);
    }
  }
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  if (n.isNew()) {
    if (!NodeUtil.constructorCallHasSideEffects(n)) {
      noSideEffectCalls.add(generateNameString(n.getFirstChild()));
    }
  } else if (n.isCall()) {
    if (!NodeUtil.functionCallHasSideEffects(n)) {
      noSideEffectCalls.add(generateNameString(n.getFirstChild()));
    }
    if (NodeUtil.callHasLocalResult(n)) {
      localResultCalls.add(generateNameString(n.getFirstChild()));
    }
  }
}
 

private boolean isMinerrCall(Node ast) {
  if (ast.isCall()) {
    Node nameNode = ast.getFirstChild();
    if (nameNode.isName()) {
      String name = nameNode.getString();
      return name.equals("minErr");
    }
  }
  return false;
}
 

/**
 * Logic for when a getprop can be replaced.
 * Can't alias a call to eval per ECMA-262 spec section 15.1.2.1
 * Can't be an assign -> no a.b = c;
 * Can't be inc or dec -> no a.b++; or a.b--;
 * Must be a GETPROP (NODE, A) where A is a reserved name
 * @param propNameNode Property name node
 * @param getPropNode GETPROP node
 * @param parent parent node
 * @return True if can be replaced
 */
private boolean canReplaceWithGetProp(Node propNameNode, Node getPropNode,
      Node parent) {
  boolean isCallTarget = (parent.isCall())
      && (parent.getFirstChild() == getPropNode);
  boolean isAssignTarget = NodeUtil.isAssignmentOp(parent)
      && (parent.getFirstChild() == getPropNode);
  boolean isIncOrDec = (parent.isInc()) ||
      (parent.isDec());
  return (propNameNode.isString()) && !isAssignTarget
      && (!isCallTarget || !"eval".equals(propNameNode.getString()))
      && !isIncOrDec
      && props.containsKey(propNameNode.getString());
}
 

/**
 * @return Whether node is a call to methodName.
 *    a.f(...)
 *    a['f'](...)
 */
static boolean isObjectCallMethod(Node callNode, String methodName) {
  if (callNode.isCall()) {
    Node functionIndentifyingExpression = callNode.getFirstChild();
    if (isGet(functionIndentifyingExpression)) {
      Node last = functionIndentifyingExpression.getLastChild();
      if (last != null && last.isString()) {
        String propName = last.getString();
        return (propName.equals(methodName));
      }
    }
  }
  return false;
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  if (n.isCall()) {
    Node target = n.getFirstChild();
    // TODO(johnlenz): add this to the coding convention
    // so we can remove goog.reflect.sinkValue as well.
    if (target.isName() && target.getString().equals(PROTECTOR_FN)) {
      Node expr = n.getLastChild();
      n.detachChildren();
      parent.replaceChild(n, expr);
    }
  }
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  if (n.isCall()) {
    Node target = n.getFirstChild();
    // TODO(johnlenz): add this to the coding convention
    // so we can remove goog.reflect.sinkValue as well.
    if (target.isName() && target.getString().equals(PROTECTOR_FN)) {
      Node expr = n.getLastChild();
      n.detachChildren();
      parent.replaceChild(n, expr);
    }
  }
}
 

protected static boolean isGoogModuleCall(Node statement) {
  if (!statement.isExprResult()) {
    return false;
  }

  Node expression = statement.getFirstChild();
  return expression.isCall() && expression.getFirstChild().matchesQualifiedName("goog.module");
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  switch (n.getType()) {

    case Token.NAME:
    case Token.GETPROP:
      String name = n.getQualifiedName();
      if (name == null) {
        return;
      }

      if (parent.isAssign() || parent.isVar()) {
        definitionMap.put(name, parent);
      }

      // Only handle function calls. This avoids assignments
      // that do not export items directly.
      if (!parent.isCall()) {
        return;
      }

      if (exportPropertyFunctionNames.contains(name)) {
        handlePropertyExport(parent);
      }

      if (exportSymbolFunctionNames.contains(name)) {
        handleSymbolExport(parent);
      }
  }
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  if (n.isCall()) {
    Node target = n.getFirstChild();
    // TODO(johnlenz): add this to the coding convention
    // so we can remove goog.reflect.sinkValue as well.
    if (target.isName() && target.getString().equals(PROTECTOR_FN)) {
      Node expr = n.getLastChild();
      n.detachChildren();
      parent.replaceChild(n, expr);
    }
  }
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  // VOID nodes appear when there are extra semicolons at the BLOCK level.
  // I've been unable to think of any cases where this indicates a bug,
  // and apparently some people like keeping these semicolons around,
  // so we'll allow it.
  if (n.isEmpty() ||
      n.isComma()) {
    return;
  }

  if (parent == null) {
    return;
  }

  // Do not try to remove a block or an expr result. We already handle
  // these cases when we visit the child, and the peephole passes will
  // fix up the tree in more clever ways when these are removed.
  if (parent.getType() == Token.COMMA) {
    Node gramps = parent.getParent();
    if (gramps.isCall() && parent == gramps.getFirstChild()) {
      if (n == parent.getFirstChild() && parent.getChildCount() == 2 && n.getNext().isName() && "eval".equals(n.getNext().getString())) {
    return;
      }
  }

  // This no-op statement was there so that JSDoc information could
  // be attached to the name. This check should not complain about it.
    if (n == parent.getLastChild()) {
      for (Node an : parent.getAncestors()) {
        int ancestorType = an.getType();
        if (ancestorType == Token.COMMA)
          continue;
        if (ancestorType != Token.EXPR_RESULT && ancestorType != Token.BLOCK)
          return;
        else
          break;
      }
    }
  } else if (parent.getType() != Token.EXPR_RESULT && parent.getType() != Token.BLOCK) {
    if (parent.getType() == Token.FOR && parent.getChildCount() == 4 && (n == parent.getFirstChild() ||
         n == parent.getFirstChild().getNext().getNext())) {
    } else {
    return;
    }
  }

  boolean isResultUsed = NodeUtil.isExpressionResultUsed(n);
  boolean isSimpleOp = NodeUtil.isSimpleOperatorType(n.getType());
  if (!isResultUsed &&
      (isSimpleOp || !NodeUtil.mayHaveSideEffects(n, t.getCompiler()))) {
    if (n.isQualifiedName() && n.getJSDocInfo() != null) {
      return;
    } else if (n.isExprResult()) {
      return;
    }
    String msg = "This code lacks side-effects. Is there a bug?";
    if (n.isString()) {
      msg = "Is there a missing '+' on the previous line?";
    } else if (isSimpleOp) {
      msg = "The result of the '" + Token.name(n.getType()).toLowerCase() +
          "' operator is not being used.";
    }

    t.getCompiler().report(
        t.makeError(n, level, USELESS_CODE_ERROR, msg));
    // TODO(johnlenz): determine if it is necessary to
    // try to protect side-effect free statements as well.
    if (!NodeUtil.isStatement(n)) {
      problemNodes.add(n);
    }
  }
}
 

@Override
public void visit(NodeTraversal t, Node n, Node parent) {
  // VOID nodes appear when there are extra semicolons at the BLOCK level.
  // I've been unable to think of any cases where this indicates a bug,
  // and apparently some people like keeping these semicolons around,
  // so we'll allow it.
  if (n.isEmpty() ||
      n.isComma()) {
    return;
  }

  if (parent == null) {
    return;
  }

  // Do not try to remove a block or an expr result. We already handle
  // these cases when we visit the child, and the peephole passes will
  // fix up the tree in more clever ways when these are removed.
  if (parent.getType() == Token.COMMA) {
    Node gramps = parent.getParent();
    if (gramps.isCall() && parent == gramps.getFirstChild()) {
      if (n == parent.getFirstChild() && parent.getChildCount() == 2 && n.getNext().isName() && "eval".equals(n.getNext().getString())) {
    return;
      }
  }

  } else if (parent.getType() != Token.EXPR_RESULT && parent.getType() != Token.BLOCK) {
    if (parent.getType() == Token.FOR && parent.getChildCount() == 4 && (n == parent.getFirstChild() ||
         n == parent.getFirstChild().getNext().getNext())) {
    } else {
    return;
    }
  }

  boolean isResultUsed = NodeUtil.isExpressionResultUsed(n);
  boolean isSimpleOp = NodeUtil.isSimpleOperatorType(n.getType());
  if (!isResultUsed &&
      (isSimpleOp || !NodeUtil.mayHaveSideEffects(n, t.getCompiler()))) {
    if (n.isQualifiedName() && n.getJSDocInfo() != null) {
      return;
    } else if (n.isExprResult()) {
      return;
    }
    String msg = "This code lacks side-effects. Is there a bug?";
    if (n.isString()) {
      msg = "Is there a missing '+' on the previous line?";
    } else if (isSimpleOp) {
      msg = "The result of the '" + Token.name(n.getType()).toLowerCase() +
          "' operator is not being used.";
    }

    t.getCompiler().report(
        t.makeError(n, level, USELESS_CODE_ERROR, msg));
    // TODO(johnlenz): determine if it is necessary to
    // try to protect side-effect free statements as well.
    if (!NodeUtil.isStatement(n)) {
      problemNodes.add(n);
    }
  }
}
 

/**
 * @return Whether the definitionSite represents a function whose call
 *      signature can be modified.
 */
private boolean canChangeSignature(Node function) {
  Definition definition = getFunctionDefinition(function);
  CodingConvention convention = compiler.getCodingConvention();

  Preconditions.checkState(!definition.isExtern());

  Collection<UseSite> useSites = defFinder.getUseSites(definition);
  for (UseSite site : useSites) {
    Node parent = site.node.getParent();

    // This was a use site removed by something else before we run.
    // 1. By another pass before us which means the definition graph is
    //    no updated properly.
    // 2. By the continuations algorithm above.
    if (parent == null) {
      continue; // Ignore it.
    }

    // Ignore references within goog.inherits calls.
    if (parent.isCall() &&
        convention.getClassesDefinedByCall(parent) != null) {
      continue;
    }

    // Accessing the property directly prevents rewrite.
    if (!SimpleDefinitionFinder.isCallOrNewSite(site)) {
      if (!(parent.isGetProp() &&
          NodeUtil.isFunctionObjectCall(parent.getParent()))) {
        return false;
      }
    }

    if (NodeUtil.isFunctionObjectApply(parent)) {
      return false;
    }

    // TODO(johnlenz): support specialization

    // Multiple definitions prevent rewrite.
    // Attempt to validate the state of the simple definition finder.
    Node nameNode = site.node;
    Collection<Definition> singleSiteDefinitions =
        defFinder.getDefinitionsReferencedAt(nameNode);
    Preconditions.checkState(singleSiteDefinitions.size() == 1);
    Preconditions.checkState(singleSiteDefinitions.contains(definition));
  }

  return true;
}
 

/**
 * @return Whether the definitionSite represents a function whose call
 *      signature can be modified.
 */
private boolean canChangeSignature(Node function) {
  Definition definition = getFunctionDefinition(function);
  CodingConvention convention = compiler.getCodingConvention();

  Preconditions.checkState(!definition.isExtern());

  Collection<UseSite> useSites = defFinder.getUseSites(definition);
  for (UseSite site : useSites) {
    Node parent = site.node.getParent();

    // This was a use site removed by something else before we run.
    // 1. By another pass before us which means the definition graph is
    //    no updated properly.
    // 2. By the continuations algorithm above.
    if (parent == null) {
      continue; // Ignore it.
    }

    // Ignore references within goog.inherits calls.
    if (parent.isCall() &&
        convention.getClassesDefinedByCall(parent) != null) {
      continue;
    }

    // Accessing the property directly prevents rewrite.
    if (!SimpleDefinitionFinder.isCallOrNewSite(site)) {
      if (!(parent.isGetProp() &&
          NodeUtil.isFunctionObjectCall(parent.getParent()))) {
        return false;
      }
    }

    if (NodeUtil.isFunctionObjectApply(parent)) {
      return false;
    }

    // TODO(johnlenz): support specialization

    // Multiple definitions prevent rewrite.
    // Attempt to validate the state of the simple definition finder.
    Node nameNode = site.node;
    Collection<Definition> singleSiteDefinitions =
        defFinder.getDefinitionsReferencedAt(nameNode);
    Preconditions.checkState(singleSiteDefinitions.size() == 1);
    Preconditions.checkState(singleSiteDefinitions.contains(definition));
  }

  return true;
}
 

private boolean isCallToScopeMethod(Node n) {
  return n.isCall() &&
      SCOPING_METHOD_NAME.equals(n.getFirstChild().getQualifiedName());
}
 

/**
 * @param node A node
 * @return Whether the call is a NEW or CALL node.
 */
static boolean isCallOrNew(Node node) {
  return node.isCall() || node.isNew();
}