Rework parser to better match the spec for UnaryExpression and Update…

…Expression. Relevant productions are: UnaryExpression := UpdateExpression { delete | void | typeof | + | - | ~ | ! } UnaryExpression UpdateExpression := { ++ | -- } UnaryExpression LeftHandSideExpression [no LineTerminator here] { ++ | -- } This is preparatory work for adding ExponentiationExpression (** operator). ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=127963105
google · Jul 21, 2016 · 5eb8043 · 5eb8043
1 parent 7505969
commit 5eb8043
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Showing 6 changed files with 104 additions and 78 deletions.
diff --git a/src/com/google/javascript/jscomp/parsing/IRFactory.java b/src/com/google/javascript/jscomp/parsing/IRFactory.java
@@ -109,7 +109,6 @@
 import com.google.javascript.jscomp.parsing.parser.trees.ParenExpressionTree;
 import com.google.javascript.jscomp.parsing.parser.trees.ParseTree;
 import com.google.javascript.jscomp.parsing.parser.trees.ParseTreeType;
-import com.google.javascript.jscomp.parsing.parser.trees.PostfixExpressionTree;
 import com.google.javascript.jscomp.parsing.parser.trees.ProgramTree;
 import com.google.javascript.jscomp.parsing.parser.trees.PropertyNameAssignmentTree;
 import com.google.javascript.jscomp.parsing.parser.trees.RecordTypeTree;
@@ -131,6 +130,8 @@
 import com.google.javascript.jscomp.parsing.parser.trees.TypedParameterTree;
 import com.google.javascript.jscomp.parsing.parser.trees.UnaryExpressionTree;
 import com.google.javascript.jscomp.parsing.parser.trees.UnionTypeTree;
+import com.google.javascript.jscomp.parsing.parser.trees.UpdateExpressionTree;
+import com.google.javascript.jscomp.parsing.parser.trees.UpdateExpressionTree.OperatorPosition;
 import com.google.javascript.jscomp.parsing.parser.trees.VariableDeclarationListTree;
 import com.google.javascript.jscomp.parsing.parser.trees.VariableDeclarationTree;
 import com.google.javascript.jscomp.parsing.parser.trees.VariableStatementTree;
@@ -717,7 +718,7 @@ private boolean shouldAttachJSDocHere(ParseTree tree) {
       case BINARY_OPERATOR:
       case MEMBER_EXPRESSION:
       case MEMBER_LOOKUP_EXPRESSION:
-      case POSTFIX_EXPRESSION:
+      case UPDATE_EXPRESSION:
         ParseTree nearest = findNearestNode(tree);
         if (nearest.type == ParseTreeType.PAREN_EXPRESSION) {
           return false;
@@ -749,8 +750,8 @@ private static ParseTree findNearestNode(ParseTree tree) {
         case MEMBER_LOOKUP_EXPRESSION:
           tree = tree.asMemberLookupExpression().operand;
           continue;
-        case POSTFIX_EXPRESSION:
+        case UPDATE_EXPRESSION:
-          tree = tree.asPostfixExpression().operand;
+          tree = tree.asUpdateExpression().operand;
           continue;
         default:
           return tree;
@@ -1921,25 +1922,20 @@ Node processUnaryExpression(UnaryExpressionTree exprNode) {
               msg,
               sourceName,
               operand.getLineno(), 0);
-        } else if (type == Token.INC || type == Token.DEC) {
-          return createIncrDecrNode(type, false, operand);
         }
 
         return newNode(type, operand);
       }
     }
 
-    Node processPostfixExpression(PostfixExpressionTree exprNode) {
+    Node processUpdateExpression(UpdateExpressionTree updateExpr) {
-      Token type = transformPostfixTokenType(exprNode.operator.type);
+      Token type = transformUpdateTokenType(updateExpr.operator.type);
-      Node operand = transform(exprNode.operand);
+      Node operand = transform(updateExpr.operand);
-      if (type == Token.INC || type == Token.DEC) {
+      return createUpdateNode(
-        return createIncrDecrNode(type, true, operand);
+          type, updateExpr.operatorPosition == OperatorPosition.POSTFIX, operand);
-      }
-      Node node = newNode(type, operand);
-      return node;
     }
 
-    private Node createIncrDecrNode(Token type, boolean postfix, Node operand) {
+    private Node createUpdateNode(Token type, boolean postfix, Node operand) {
       if (!operand.isValidAssignmentTarget()) {
         errorReporter.error(
             SimpleFormat.format("Invalid %s %s operand.",
@@ -2712,8 +2708,8 @@ public Node process(ParseTree node) {
           return processComputedPropertySetter(node.asComputedPropertySetter());
         case RETURN_STATEMENT:
           return processReturnStatement(node.asReturnStatement());
-        case POSTFIX_EXPRESSION:
+        case UPDATE_EXPRESSION:
-          return processPostfixExpression(node.asPostfixExpression());
+          return processUpdateExpression(node.asUpdateExpression());
         case PROGRAM:
           return processAstRoot(node.asProgram());
         case LITERAL_EXPRESSION: // STRING, NUMBER, TRUE, FALSE, NULL, REGEXP
@@ -3136,7 +3132,7 @@ static Token transformBooleanTokenType(TokenType token) {
     }
   }
 
-  static Token transformPostfixTokenType(TokenType token) {
+  static Token transformUpdateTokenType(TokenType token) {
     switch (token) {
       case PLUS_PLUS:
         return Token.INC;
@@ -3163,11 +3159,6 @@ static Token transformUnaryTokenType(TokenType token) {
       case TYPEOF:
         return Token.TYPEOF;
 
-      case PLUS_PLUS:
-        return Token.INC;
-      case MINUS_MINUS:
-        return Token.DEC;
-
       case VOID:
         return Token.VOID;
 

diff --git a/src/com/google/javascript/jscomp/parsing/parser/Parser.java b/src/com/google/javascript/jscomp/parsing/parser/Parser.java
@@ -87,7 +87,6 @@
 import com.google.javascript.jscomp.parsing.parser.trees.ParenExpressionTree;
 import com.google.javascript.jscomp.parsing.parser.trees.ParseTree;
 import com.google.javascript.jscomp.parsing.parser.trees.ParseTreeType;
-import com.google.javascript.jscomp.parsing.parser.trees.PostfixExpressionTree;
 import com.google.javascript.jscomp.parsing.parser.trees.ProgramTree;
 import com.google.javascript.jscomp.parsing.parser.trees.PropertyNameAssignmentTree;
 import com.google.javascript.jscomp.parsing.parser.trees.RecordTypeTree;
@@ -109,6 +108,7 @@
 import com.google.javascript.jscomp.parsing.parser.trees.TypedParameterTree;
 import com.google.javascript.jscomp.parsing.parser.trees.UnaryExpressionTree;
 import com.google.javascript.jscomp.parsing.parser.trees.UnionTypeTree;
+import com.google.javascript.jscomp.parsing.parser.trees.UpdateExpressionTree;
 import com.google.javascript.jscomp.parsing.parser.trees.VariableDeclarationListTree;
 import com.google.javascript.jscomp.parsing.parser.trees.VariableDeclarationTree;
 import com.google.javascript.jscomp.parsing.parser.trees.VariableStatementTree;
@@ -3223,7 +3223,7 @@ private ParseTree parseUnaryExpression() {
     } else if (peekAwaitExpression()) {
       return parseAwaitExpression();
     } else {
-      return parsePostfixExpression();
+      return parseUpdateExpression();
     }
   }
 
@@ -3232,8 +3232,6 @@ private boolean peekUnaryOperator() {
     case DELETE:
     case VOID:
     case TYPEOF:
-    case PLUS_PLUS:
-    case MINUS_MINUS:
     case PLUS:
     case MINUS:
     case TILDE:
@@ -3259,27 +3257,31 @@ private ParseTree parseAwaitExpression() {
     return new AwaitExpressionTree(getTreeLocation(start), expression);
   }
 
-  // 11.3 Postfix Expression
+  private ParseTree parseUpdateExpression() {
-  private ParseTree parsePostfixExpression() {
     SourcePosition start = getTreeStartLocation();
-    ParseTree operand = parseLeftHandSideExpression();
+    if (peekUpdateOperator()) {
-    while (peekPostfixOperator()) {
       Token operator = nextToken();
-      operand = new PostfixExpressionTree(getTreeLocation(start), operand, operator);
+      ParseTree operand = parseUnaryExpression();
+      return UpdateExpressionTree.prefix(getTreeLocation(start), operator, operand);
+    } else {
+      ParseTree lhs = parseLeftHandSideExpression();
+      if (peekUpdateOperator() && !peekImplicitSemiColon()) {
+        // newline not allowed before an update operator.
+        Token operator = nextToken();
+        return UpdateExpressionTree.postfix(getTreeLocation(start), operator, lhs);
+      } else {
+        return lhs;
+      }
     }
-    return operand;
   }
 
-  private boolean peekPostfixOperator() {
+  private boolean peekUpdateOperator() {
-    if (peekImplicitSemiColon()) {
-      return false;
-    }
     switch (peekType()) {
-    case PLUS_PLUS:
+      case PLUS_PLUS:
-    case MINUS_MINUS:
+      case MINUS_MINUS:
-      return true;
+        return true;
-    default:
+      default:
-      return false;
+        return false;
     }
   }
 

diff --git a/src/com/google/javascript/jscomp/parsing/parser/trees/ParseTree.java b/src/com/google/javascript/jscomp/parsing/parser/trees/ParseTree.java
@@ -114,7 +114,6 @@ public ObjectLiteralExpressionTree asObjectLiteralExpression() {
     return (ObjectLiteralExpressionTree) this; }
   public ObjectPatternTree asObjectPattern() { return (ObjectPatternTree) this; }
   public ParenExpressionTree asParenExpression() { return (ParenExpressionTree) this; }
-  public PostfixExpressionTree asPostfixExpression() { return (PostfixExpressionTree) this; }
   public ProgramTree asProgram() { return (ProgramTree) this; }
   public PropertyNameAssignmentTree asPropertyNameAssignment() {
     return (PropertyNameAssignmentTree) this; }
@@ -170,6 +169,11 @@ public NamespaceDeclarationTree asNamespaceDeclaration() {
   public NewTargetExpressionTree asNewTargetExpression() {
     return (NewTargetExpressionTree) this;
   }
+
+  public UpdateExpressionTree asUpdateExpression() {
+    return (UpdateExpressionTree) this;
+  }
+
   public boolean isPattern() {
     ParseTree parseTree = this;
     while (parseTree.type == ParseTreeType.PAREN_EXPRESSION) {

diff --git a/src/com/google/javascript/jscomp/parsing/parser/trees/ParseTreeType.java b/src/com/google/javascript/jscomp/parsing/parser/trees/ParseTreeType.java
@@ -68,7 +68,7 @@ public enum ParseTreeType {
   BINARY_OPERATOR,
   CONDITIONAL_EXPRESSION,
   UNARY_EXPRESSION,
-  POSTFIX_EXPRESSION,
+  UPDATE_EXPRESSION,
   MEMBER_EXPRESSION,
   NEW_EXPRESSION,
   ARGUMENT_LIST,

diff --git a/src/com/google/javascript/jscomp/parsing/parser/trees/PostfixExpressionTree.java b/src/com/google/javascript/jscomp/parsing/parser/trees/PostfixExpressionTree.java
diff --git a/src/com/google/javascript/jscomp/parsing/parser/trees/UpdateExpressionTree.java b/src/com/google/javascript/jscomp/parsing/parser/trees/UpdateExpressionTree.java
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2016 The Closure Compiler Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.javascript.jscomp.parsing.parser.trees;
+
+import com.google.javascript.jscomp.parsing.parser.Token;
+import com.google.javascript.jscomp.parsing.parser.util.SourceRange;
+
+/**
+ * Represents UpdateExpression productions from the spec.
+ *
+ * <pre><code>
+ * UpdateExpression :=
+ *     { ++ | -- } UnaryExpression
+ *     LeftHandSideExpression [no LineTerminator here] { ++ | -- }
+ * </code></pre>
+ */
+public class UpdateExpressionTree extends ParseTree {
+
+  /**
+   * Position of the operator relative to the operand.
+   */
+  public enum OperatorPosition {
+    PREFIX,
+    POSTFIX;
+  }
+
+  public final Token operator;
+  public final OperatorPosition operatorPosition;
+  public final ParseTree operand;
+
+  public UpdateExpressionTree(
+      SourceRange location, Token operator, OperatorPosition operatorPosition, ParseTree operand) {
+    super(ParseTreeType.UPDATE_EXPRESSION, location);
+
+    this.operator = operator;
+    this.operatorPosition = operatorPosition;
+    this.operand = operand;
+  }
+
+  public static UpdateExpressionTree prefix(
+      SourceRange location, Token operator, ParseTree operand) {
+    return new UpdateExpressionTree(location, operator, OperatorPosition.PREFIX, operand);
+  }
+
+  public static UpdateExpressionTree postfix(
+      SourceRange location, Token operator, ParseTree operand) {
+    return new UpdateExpressionTree(location, operator, OperatorPosition.POSTFIX, operand);
+  }
+}