示例#1
0
  private void validateParametersEs6(Node n) {
    boolean defaultParams = false;
    for (Node c = n.getFirstChild(); c != null; c = c.getNext()) {
      if (c.isRest()) {
        if (c.getNext() != null) {
          violation("Rest parameters must come after all other parameters.", c);
        }
        validateRest(c);
      } else if (c.isDefaultValue()) {
        defaultParams = true;
        validateDefaultValue(Token.PARAM_LIST, c);
      } else {
        if (defaultParams) {
          violation(
              "Cannot have a parameter without a default value,"
                  + " after one with a default value.",
              c);
        }

        if (c.isName()) {
          validateName(c);
        } else if (c.isArrayPattern()) {
          validateArrayPattern(Token.PARAM_LIST, c);
        } else {
          validateObjectPattern(Token.PARAM_LIST, c);
        }
      }
    }
  }
  /** Processes trailing default and rest parameters. */
  private void visitParamList(Node paramList, Node function) {
    Node insertSpot = null;
    Node block = function.getLastChild();
    for (int i = 0; i < paramList.getChildCount(); i++) {
      Node param = paramList.getChildAtIndex(i);
      if (param.isDefaultValue()) {
        Node nameOrPattern = param.removeFirstChild();
        Node defaultValue = param.removeFirstChild();
        Node newParam =
            nameOrPattern.isName()
                ? nameOrPattern
                : IR.name(DESTRUCTURING_TEMP_VAR + (destructuringVarCounter++));

        Node lhs = nameOrPattern.cloneTree();
        Node rhs = defaultValueHook(newParam.cloneTree(), defaultValue);
        Node newStatement =
            nameOrPattern.isName() ? IR.exprResult(IR.assign(lhs, rhs)) : IR.var(lhs, rhs);
        newStatement.useSourceInfoIfMissingFromForTree(param);
        block.addChildAfter(newStatement, insertSpot);
        insertSpot = newStatement;

        paramList.replaceChild(param, newParam);
        newParam.setOptionalArg(true);

        compiler.reportCodeChange();
      } else if (param.isRest()) { // rest parameter
        param.setType(Token.NAME);
        param.setVarArgs(true);
        // Transpile to: param = [].slice.call(arguments, i);
        Node newArr =
            IR.exprResult(
                IR.assign(
                    IR.name(param.getString()),
                    IR.call(
                        IR.getprop(
                            IR.getprop(IR.arraylit(), IR.string("slice")), IR.string("call")),
                        IR.name("arguments"),
                        IR.number(i))));
        block.addChildAfter(newArr.useSourceInfoIfMissingFromForTree(param), insertSpot);
        compiler.reportCodeChange();
      } else if (param.isDestructuringPattern()) {
        String tempVarName = DESTRUCTURING_TEMP_VAR + (destructuringVarCounter++);
        paramList.replaceChild(param, IR.name(tempVarName));
        Node newDecl = IR.var(param, IR.name(tempVarName));
        block.addChildAfter(newDecl, insertSpot);
        insertSpot = newDecl;
      }
    }
    // For now, we are running transpilation before type-checking, so we'll
    // need to make sure changes don't invalidate the JSDoc annotations.
    // Therefore we keep the parameter list the same length and only initialize
    // the values if they are set to undefined.
  }
示例#3
0
 private void validateNameDeclarationChild(int type, Node n) {
   if (n.isName()) {
     // Don't use validateName here since this NAME node may have
     // a child.
     validateNonEmptyString(n);
     validateMaximumChildCount(n, 1);
     if (n.hasChildren()) {
       validateExpression(n.getFirstChild());
     }
   } else if (n.isArrayPattern()) {
     validateArrayPattern(type, n);
   } else if (n.isObjectPattern()) {
     validateObjectPattern(type, n);
   } else if (n.isDefaultValue()) {
     validateDefaultValue(type, n);
   } else if (n.isComputedProp()) {
     validateObjectPatternComputedPropKey(type, n);
   } else {
     violation("Invalid child for " + Token.name(type) + " node", n);
   }
 }
    private static boolean isDeclarationHelper(Node node) {
      Node parent = node.getParent();

      // Special case for class B extends A, A is not a declaration.
      if (parent.isClass() && node != parent.getFirstChild()) {
        return false;
      }

      // This condition can be true during InlineVariables.
      if (parent.getParent() == null) {
        return false;
      }

      if (NodeUtil.isNameDeclaration(parent.getParent()) && node == parent.getLastChild()) {
        // Unless it is something like "for (var/let/const a of x){}",
        // this is the RHS of a var/let/const and thus not a declaration.
        if (parent.getParent().getParent() == null || !parent.getParent().getParent().isForOf()) {
          return false;
        }
      }

      // Special cases for destructuring patterns.
      if (parent.isDestructuringPattern()
          || (parent.isStringKey() && parent.getParent().isObjectPattern())
          || (parent.isComputedProp()
              && parent.getParent().isObjectPattern()
              && node == parent.getLastChild())
          || (parent.isDefaultValue() && node == parent.getFirstChild())) {
        return isDeclarationHelper(parent);
      }

      // Special case for arrow function
      if (parent.isArrowFunction()) {
        return node == parent.getFirstChild();
      }

      return DECLARATION_PARENTS.contains(parent.getType());
    }
  private void visitArrayPattern(NodeTraversal t, Node arrayPattern, Node parent) {
    Node rhs, nodeToDetach;
    if (NodeUtil.isNameDeclaration(parent) && !NodeUtil.isEnhancedFor(parent.getParent())) {
      // The array pattern is the only child, because Es6SplitVariableDeclarations
      // has already run.
      Preconditions.checkState(arrayPattern.getNext() == null);
      rhs = arrayPattern.getLastChild();
      nodeToDetach = parent;
    } else if (parent.isAssign()) {
      rhs = arrayPattern.getNext();
      nodeToDetach = parent.getParent();
      Preconditions.checkState(nodeToDetach.isExprResult());
    } else if (parent.isArrayPattern() || parent.isDefaultValue() || parent.isStringKey()) {
      // This is a nested array pattern. Don't do anything now; we'll visit it
      // after visiting the parent.
      return;
    } else if (NodeUtil.isEnhancedFor(parent) || NodeUtil.isEnhancedFor(parent.getParent())) {
      visitDestructuringPatternInEnhancedFor(arrayPattern);
      return;
    } else {
      Preconditions.checkState(parent.isCatch() || parent.isForOf());
      cannotConvertYet(
          arrayPattern, "ARRAY_PATTERN that is a child of a " + Token.name(parent.getType()));
      return;
    }

    // Convert 'var [x, y] = rhs' to:
    // var temp = rhs;
    // var x = temp[0];
    // var y = temp[1];
    String tempVarName = DESTRUCTURING_TEMP_VAR + (destructuringVarCounter++);
    Node tempDecl =
        IR.var(IR.name(tempVarName), rhs.detachFromParent())
            .useSourceInfoIfMissingFromForTree(arrayPattern);
    nodeToDetach.getParent().addChildBefore(tempDecl, nodeToDetach);

    int i = 0;
    for (Node child = arrayPattern.getFirstChild(), next; child != null; child = next, i++) {
      next = child.getNext();
      if (child.isEmpty()) {
        continue;
      }

      Node newLHS, newRHS;
      if (child.isDefaultValue()) {
        Node getElem = IR.getelem(IR.name(tempVarName), IR.number(i));
        //   [x = defaultValue] = rhs;
        // becomes
        //   var temp = rhs;
        //   x = (temp[0] === undefined) ? defaultValue : temp[0];
        newLHS = child.getFirstChild().detachFromParent();
        newRHS = defaultValueHook(getElem, child.getLastChild().detachFromParent());
      } else if (child.isRest()) {
        newLHS = child.detachFromParent();
        newLHS.setType(Token.NAME);
        // [].slice.call(temp, i)
        newRHS =
            IR.call(
                IR.getprop(IR.getprop(IR.arraylit(), IR.string("slice")), IR.string("call")),
                IR.name(tempVarName),
                IR.number(i));
      } else {
        newLHS = child.detachFromParent();
        newRHS = IR.getelem(IR.name(tempVarName), IR.number(i));
      }
      Node newNode;
      if (parent.isAssign()) {
        Node assignment = IR.assign(newLHS, newRHS);
        newNode = IR.exprResult(assignment);
      } else {
        newNode = IR.declaration(newLHS, newRHS, parent.getType());
      }
      newNode.useSourceInfoIfMissingFromForTree(arrayPattern);

      nodeToDetach.getParent().addChildBefore(newNode, nodeToDetach);
      // Explicitly visit the LHS of the new node since it may be a nested
      // destructuring pattern.
      visit(t, newLHS, newLHS.getParent());
    }
    nodeToDetach.detachFromParent();
    compiler.reportCodeChange();
  }
  private void visitObjectPattern(NodeTraversal t, Node objectPattern, Node parent) {
    Node rhs, nodeToDetach;
    if (NodeUtil.isNameDeclaration(parent) && !NodeUtil.isEnhancedFor(parent.getParent())) {
      rhs = objectPattern.getLastChild();
      nodeToDetach = parent;
    } else if (parent.isAssign() && parent.getParent().isExprResult()) {
      rhs = parent.getLastChild();
      nodeToDetach = parent.getParent();
    } else if (parent.isStringKey() || parent.isArrayPattern() || parent.isDefaultValue()) {
      // Nested object pattern; do nothing. We will visit it after rewriting the parent.
      return;
    } else if (NodeUtil.isEnhancedFor(parent) || NodeUtil.isEnhancedFor(parent.getParent())) {
      visitDestructuringPatternInEnhancedFor(objectPattern);
      return;
    } else {
      Preconditions.checkState(parent.isCatch(), parent);
      cannotConvertYet(
          objectPattern, "OBJECT_PATTERN that is a child of a " + Token.name(parent.getType()));
      return;
    }

    // Convert 'var {a: b, c: d} = rhs' to:
    // var temp = rhs;
    // var b = temp.a;
    // var d = temp.c;
    String tempVarName = DESTRUCTURING_TEMP_VAR + (destructuringVarCounter++);
    Node tempDecl =
        IR.var(IR.name(tempVarName), rhs.detachFromParent())
            .useSourceInfoIfMissingFromForTree(objectPattern);
    nodeToDetach.getParent().addChildBefore(tempDecl, nodeToDetach);

    for (Node child = objectPattern.getFirstChild(), next; child != null; child = next) {
      next = child.getNext();

      Node newLHS, newRHS;
      if (child.isStringKey()) {
        Preconditions.checkState(child.hasChildren());
        Node getprop =
            new Node(
                child.isQuotedString() ? Token.GETELEM : Token.GETPROP,
                IR.name(tempVarName),
                IR.string(child.getString()));

        Node value = child.removeFirstChild();
        if (!value.isDefaultValue()) {
          newLHS = value;
          newRHS = getprop;
        } else {
          newLHS = value.removeFirstChild();
          Node defaultValue = value.removeFirstChild();
          newRHS = defaultValueHook(getprop, defaultValue);
        }
      } else if (child.isComputedProp()) {
        if (child.getLastChild().isDefaultValue()) {
          newLHS = child.getLastChild().removeFirstChild();
          Node getelem = IR.getelem(IR.name(tempVarName), child.removeFirstChild());

          String intermediateTempVarName = DESTRUCTURING_TEMP_VAR + (destructuringVarCounter++);
          Node intermediateDecl = IR.var(IR.name(intermediateTempVarName), getelem);
          intermediateDecl.useSourceInfoIfMissingFromForTree(child);
          nodeToDetach.getParent().addChildBefore(intermediateDecl, nodeToDetach);

          newRHS =
              defaultValueHook(
                  IR.name(intermediateTempVarName), child.getLastChild().removeFirstChild());
        } else {
          newRHS = IR.getelem(IR.name(tempVarName), child.removeFirstChild());
          newLHS = child.removeFirstChild();
        }
      } else if (child.isDefaultValue()) {
        newLHS = child.removeFirstChild();
        Node defaultValue = child.removeFirstChild();
        Node getprop = IR.getprop(IR.name(tempVarName), IR.string(newLHS.getString()));
        newRHS = defaultValueHook(getprop, defaultValue);
      } else {
        throw new IllegalStateException("Unexpected OBJECT_PATTERN child: " + child);
      }

      Node newNode;
      if (NodeUtil.isNameDeclaration(parent)) {
        newNode = IR.declaration(newLHS, newRHS, parent.getType());
      } else if (parent.isAssign()) {
        newNode = IR.exprResult(IR.assign(newLHS, newRHS));
      } else {
        throw new IllegalStateException("not reached");
      }
      newNode.useSourceInfoIfMissingFromForTree(child);

      nodeToDetach.getParent().addChildBefore(newNode, nodeToDetach);

      // Explicitly visit the LHS of the new node since it may be a nested
      // destructuring pattern.
      visit(t, newLHS, newLHS.getParent());
    }

    nodeToDetach.detachFromParent();
    compiler.reportCodeChange();
  }