[gwt-contrib] Fixes issue 4301: ensures all strings "generated" by GWT are JS string values. (issue1623803)

[t . broyer]

Reviewers: cromwellian, scottb, jgw, knorton, jaimeyap,
Description:
Fixes issue 4301: ensures all strings "generated" by GWT are JS string
values.

Note that, in prod mode, even an assertSame(s, s.toString()) failed!

Please review this at http://gwt-code-reviews.appspot.com/1623803/

Affected files:
  M user/super/com/google/gwt/emul/java/lang/String.java
  M user/test/com/google/gwt/emultest/java/lang/StringTest.java


Index: user/super/com/google/gwt/emul/java/lang/String.java
diff --git a/user/super/com/google/gwt/emul/java/lang/String.java  
b/user/super/com/google/gwt/emul/java/lang/String.java
index  
1eb19646d93a8e6c9b2a4a262e48fbc8ea7c0de5..b35acf04c464fa1c7325f744161f462eab38c717  
100644
--- a/user/super/com/google/gwt/emul/java/lang/String.java
+++ b/user/super/com/google/gwt/emul/java/lang/String.java
@@ -957,9 +957,10 @@ public final class String implements  
Comparable<String>, CharSequence,
   }-*/;

   @Override
-  public String toString() {
-    return this;
-  }
+  public native String toString() /*-{
+    // make sure GWT strings are always JS string values (see issue 4301)
+    return String(this);
+  }-*/;

   public native String toUpperCase() /*-{
     return this.toUpperCase();
Index: user/test/com/google/gwt/emultest/java/lang/StringTest.java
diff --git a/user/test/com/google/gwt/emultest/java/lang/StringTest.java  
b/user/test/com/google/gwt/emultest/java/lang/StringTest.java
index  
46d0efb9562189a7d17b0d17365f0fe8aaf53f26..a94705c210d13cda35dd2fbe2ab860db1db9f2b7  
100644
--- a/user/test/com/google/gwt/emultest/java/lang/StringTest.java
+++ b/user/test/com/google/gwt/emultest/java/lang/StringTest.java
@@ -16,6 +16,7 @@
 package com.google.gwt.emultest.java.lang;

 import com.google.gwt.core.client.GWT;
+import com.google.gwt.core.client.JavaScriptObject;
 import com.google.gwt.junit.client.GWTTestCase;

 import java.io.UnsupportedEncodingException;
@@ -601,6 +602,13 @@ public class StringTest extends GWTTestCase {
     }
   }

+  public void testToString() {
+    Object s = Math.random() < 1 ? "abc" : JavaScriptObject.createObject();
+    assertSame(s, s.toString());
+    // issue 4301
+    assertTrue("issue4301", isJsStringValue(s.toString()));
+  }
+
   /*
    * TODO: needs rewriting to avoid compiler optimizations.
    */
@@ -666,6 +674,10 @@ public class StringTest extends GWTTestCase {
     }
   }

+  private native boolean isJsStringValue(String s) /*-{
+    return typeof s == 'string';
+  }-*/;
+
   private String returnNull() {
     return null;
   }


--
http://groups.google.com/group/Google-Web-Toolkit-Contributors