Remove the call to $jscomp.copyProperties even if there are no proper…

…ties to copy. ------------- Created by MOE: http://code.google.com/p/moe-java MOE_MIGRATED_REVID=90071042
google · Apr 2, 2015 · a9df90f · a9df90f
1 parent b8239c4
commit a9df90f
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diff --git a/src/com/google/javascript/jscomp/Es6ToEs3ClassSideInheritance.java b/src/com/google/javascript/jscomp/Es6ToEs3ClassSideInheritance.java
@@ -109,8 +109,8 @@ public void visit(NodeTraversal t, Node n, Node parent) {
           staticMembers.put(subClassName.getQualifiedName(),
               staticMember);
         }
-        parent.detachFromParent();
       }
+      parent.detachFromParent();
     }
   }
 

diff --git a/test/com/google/javascript/jscomp/IntegrationTest.java b/test/com/google/javascript/jscomp/IntegrationTest.java
@@ -2867,6 +2867,60 @@ public void testES5toES6() throws Exception {
     compile(options, code);
   }
 
+  // Tests that unused classes are removed, even if they are passed to $jscomp.inherits.
+  public void testES6UnusedClassesAreRemoved() {
+    CompilerOptions options = createCompilerOptions();
+    options.setLanguageIn(LanguageMode.ECMASCRIPT6_STRICT);
+    options.setLanguageOut(LanguageMode.ECMASCRIPT3);
+    CompilationLevel.ADVANCED_OPTIMIZATIONS.setOptionsForCompilationLevel(options);
+    Compiler compiler = compile(options, Joiner.on('\n').join(
+        "class Base {}",
+        "class Sub extends Base {}",
+        "alert(1);"));
+    String result = compiler.toSource(compiler.getJsRoot());
+    assertThat(result).isEqualTo("alert(1)");
+  }
+
+  /**
+   * @param js A snippet of JavaScript in which alert('No one ever calls me'); is called
+   *     in a method which is never called. Verifies that the method is stripped out by
+   *     asserting that the result does not contain the string 'No one ever calls me'.
+   */
+  private void testES6StaticsAreRemoved(String js) {
+    CompilerOptions options = createCompilerOptions();
+    options.setLanguageIn(LanguageMode.ECMASCRIPT6_STRICT);
+    options.setLanguageOut(LanguageMode.ECMASCRIPT3);
+    CompilationLevel.ADVANCED_OPTIMIZATIONS.setOptionsForCompilationLevel(options);
+    Compiler compiler = compile(options, js);
+    String result = compiler.toSource(compiler.getJsRoot());
+    assertThat(result).isNotEmpty();
+    assertThat(result).doesNotContain("No one ever calls me");
+  }
+
+  public void testES6StaticsAreRemoved1() {
+    testES6StaticsAreRemoved(Joiner.on('\n').join(
+        "class Base {",
+        "  static called() { alert('I am called'); }",
+        "  static notCalled() { alert('No one ever calls me'); }",
+        "}",
+        "class Sub extends Base {",
+        "  static called() { super.called(); alert('I am called too'); }",
+        "  static notCalled() { alert('No one ever calls me'); }",
+        "}",
+        "Sub.called();"));
+  }
+
+  public void failing_testES6StaticsAreRemoved2() {
+    testES6StaticsAreRemoved(Joiner.on('\n').join(
+        "class Base {",
+        "  static calledInSubclassOnly() { alert('No one ever calls me'); }",
+        "}",
+        "class Sub extends Base {",
+        "  static calledInSubclassOnly() { alert('I am called'); }",
+        "}",
+        "Sub.calledInSubclassOnly();"));
+  }
+
   public void testIssue787() {
     CompilerOptions options = createCompilerOptions();
     CompilationLevel level = CompilationLevel.SIMPLE_OPTIMIZATIONS;