diff --git a/dev/core/src/com/google/gwt/dev/MinimalRebuildCache.java b/dev/core/src/com/google/gwt/dev/MinimalRebuildCache.java
index c8dd011..76e210f 100644
--- a/dev/core/src/com/google/gwt/dev/MinimalRebuildCache.java
+++ b/dev/core/src/com/google/gwt/dev/MinimalRebuildCache.java
@@ -1,11 +1,11 @@
 /*
  * Copyright 2014 Google Inc.
- *
+ * 
  * 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
@@ -162,6 +162,8 @@
   private final Set<String> deletedDiskSourcePaths = Sets.newHashSet();
   private final Set<String> deletedResourcePaths = Sets.newHashSet();
   private final Set<String> dualJsoImplInterfaceNames = Sets.newHashSet();
+  private final Set<String> exportedGlobalNames = Sets.newHashSet();
+  private final Multimap<String, String> exportedGlobalNamesByTypeName = HashMultimap.create();
   private final ArtifactSet generatedArtifacts = new ArtifactSet();
   private final Multimap<String, String> generatedCompilationUnitNamesByReboundTypeNames =
       HashMultimap.create();
@@ -170,6 +172,7 @@
   private final JsIncrementalNamerState jsIncrementalNamerState = new JsIncrementalNamerState();
   private final Set<String> jsoStatusChangedTypeNames = Sets.newHashSet();
   private final Set<String> jsoTypeNames = Sets.newHashSet();
+  private final Multimap<String, String> jsTypeMemberNamesByTypeName = HashMultimap.create();
   private Integer lastLinkedJsBytes;
   private final Map<String, Long> lastModifiedByDiskSourcePath = Maps.newHashMap();
   private final Map<String, Long> lastModifiedByResourcePath = Maps.newHashMap();
@@ -195,6 +198,11 @@
       new StringAnalyzableTypeEnvironment(this);
   private final Multimap<String, String> typeNamesByReferencingTypeName = HashMultimap.create();
 
+  public boolean addExportedGlobalName(String exportedGlobalName, String inTypeName) {
+    exportedGlobalNamesByTypeName.put(inTypeName, exportedGlobalName);
+    return exportedGlobalNames.add(exportedGlobalName);
+  }
+
   /**
    * Accumulates generated artifacts so that they can be output on recompiles even if no generators
    * are run.
@@ -203,6 +211,10 @@
     this.generatedArtifacts.addAll(generatedArtifacts);
   }
 
+  public boolean addJsTypeMemberName(String exportedMemberName, String inTypeName) {
+    return jsTypeMemberNamesByTypeName.put(inTypeName, exportedMemberName);
+  }
+
   public void addModifiedCompilationUnitNames(TreeLogger logger,
       Set<String> modifiedCompilationUnitNames) {
     logger.log(TreeLogger.DEBUG, "adding to cached list of known modified compilation units "
@@ -466,6 +478,8 @@
     copyMap(that.sourceMapsByTypeName, this.sourceMapsByTypeName);
     copyMap(that.statementRangesByTypeName, this.statementRangesByTypeName);
 
+    copyMultimap(that.exportedGlobalNamesByTypeName, this.exportedGlobalNamesByTypeName);
+    copyMultimap(that.jsTypeMemberNamesByTypeName, this.jsTypeMemberNamesByTypeName);
     copyMultimap(that.generatedCompilationUnitNamesByReboundTypeNames,
         this.generatedCompilationUnitNamesByReboundTypeNames);
     copyMultimap(that.nestedTypeNamesByUnitTypeName, this.nestedTypeNamesByUnitTypeName);
@@ -480,6 +494,7 @@
     copyCollection(that.deletedDiskSourcePaths, this.deletedDiskSourcePaths);
     copyCollection(that.deletedResourcePaths, this.deletedResourcePaths);
     copyCollection(that.dualJsoImplInterfaceNames, this.dualJsoImplInterfaceNames);
+    copyCollection(that.exportedGlobalNames, this.exportedGlobalNames);
     copyCollection(that.generatedArtifacts, this.generatedArtifacts);
     copyCollection(that.jsoStatusChangedTypeNames, this.jsoStatusChangedTypeNames);
     copyCollection(that.jsoTypeNames, this.jsoTypeNames);
@@ -672,6 +687,13 @@
     rebinderTypeNamesByReboundTypeName.put(reboundTypeName, rebinderType);
   }
 
+  public void removeJsInteropNames(String inTypeName) {
+    jsTypeMemberNamesByTypeName.removeAll(inTypeName);
+    Collection<String> exportedGlobalNamesForType =
+        exportedGlobalNamesByTypeName.removeAll(inTypeName);
+    exportedGlobalNames.removeAll(exportedGlobalNamesForType);
+  }
+
   public void removeReferencesFrom(String fromTypeName) {
     Collection<String> toTypeNames = referencedTypeNamesByTypeName.get(fromTypeName);
     for (String toTypeName : toTypeNames) {
@@ -754,8 +776,11 @@
         && Objects.equal(this.deletedDiskSourcePaths, that.deletedDiskSourcePaths)
         && Objects.equal(this.deletedResourcePaths, that.deletedResourcePaths)
         && Objects.equal(this.dualJsoImplInterfaceNames, that.dualJsoImplInterfaceNames)
-        && Objects.equal(this.generatedArtifacts, that.generatedArtifacts) && Objects.equal(
-            this.generatedCompilationUnitNamesByReboundTypeNames,
+        && Objects.equal(this.generatedArtifacts, that.generatedArtifacts)
+        && Objects.equal(this.exportedGlobalNames, that.exportedGlobalNames)
+        && Objects.equal(this.exportedGlobalNamesByTypeName, that.exportedGlobalNamesByTypeName)
+        && Objects.equal(this.jsTypeMemberNamesByTypeName, that.jsTypeMemberNamesByTypeName)
+        && Objects.equal(this.generatedCompilationUnitNamesByReboundTypeNames,
             that.generatedCompilationUnitNamesByReboundTypeNames)
         && this.intTypeMapper.hasSameContent(that.intTypeMapper)
         && Objects.equal(this.jsByTypeName, that.jsByTypeName)
diff --git a/dev/core/src/com/google/gwt/dev/jjs/JavaToJavaScriptCompiler.java b/dev/core/src/com/google/gwt/dev/jjs/JavaToJavaScriptCompiler.java
index 3e3f72c..0dba089 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/JavaToJavaScriptCompiler.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/JavaToJavaScriptCompiler.java
@@ -75,6 +75,7 @@
 import com.google.gwt.dev.jjs.impl.JavaToJavaScriptMap;
 import com.google.gwt.dev.jjs.impl.JsAbstractTextTransformer;
 import com.google.gwt.dev.jjs.impl.JsFunctionClusterer;
+import com.google.gwt.dev.jjs.impl.JsInteropRestrictionChecker;
 import com.google.gwt.dev.jjs.impl.JsNoopTransformer;
 import com.google.gwt.dev.jjs.impl.JsTypeLinker;
 import com.google.gwt.dev.jjs.impl.JsniRestrictionChecker;
@@ -957,6 +958,7 @@
 
         // TODO(stalcup): hide metrics gathering in a callback or subclass
         JsniRestrictionChecker.exec(logger, jprogram);
+        JsInteropRestrictionChecker.exec(logger, jprogram, getMinimalRebuildCache());
         logTypeOracleMetrics(precompilationMetrics, compilationState);
         Memory.maybeDumpMemory("AstOnly");
         AstDumper.maybeDumpAST(jprogram);
diff --git a/dev/core/src/com/google/gwt/dev/jjs/ast/JDeclaredType.java b/dev/core/src/com/google/gwt/dev/jjs/ast/JDeclaredType.java
index 167b15c..a594537 100755
--- a/dev/core/src/com/google/gwt/dev/jjs/ast/JDeclaredType.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/ast/JDeclaredType.java
@@ -528,7 +528,6 @@
   }
 
   public String getQualifiedExportName() {
-
     if (enclosingType == null) {
       return jsNamespace == null || jsNamespace.isEmpty() ? getName() :
           jsNamespace + "." + getLeafName();
diff --git a/dev/core/src/com/google/gwt/dev/jjs/impl/GenerateJavaScriptAST.java b/dev/core/src/com/google/gwt/dev/jjs/impl/GenerateJavaScriptAST.java
index e845c4f..2827d7f 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/impl/GenerateJavaScriptAST.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/impl/GenerateJavaScriptAST.java
@@ -567,14 +567,20 @@
             // so that it can be referred when generating the vtable of a subclass that
             // increases the visibility of this method.
             polymorphicNames.put(typeOracle.getTopMostDefinition(x), polyName);
-
           } else if (specialObfuscatedMethodSigs.containsKey(x.getSignature())) {
             polyName = interfaceScope.declareName(mangleNameSpecialObfuscate(x));
             polyName.setObfuscatable(false);
             // if a JsType and we can set set the interface method to non-obfuscatable
           } else if (typeOracle.isJsTypeMethod(x) && !typeOracle.needsJsInteropBridgeMethod(x)) {
-            polyName = interfaceScope.declareName(name, name);
-            polyName.setObfuscatable(false);
+            if (x.isJsProperty()) {
+              // Prevent JsProperty functions like x() from colliding with intended JS native
+              // properties like .x;
+              polyName = interfaceScope.declareName(mangleNameForJsProperty(x), name);
+            } else {
+              // Leave simple JsType dispatches clean and unobfuscated.
+              polyName = interfaceScope.declareName(name, name);
+              polyName.setObfuscatable(false);
+            }
           } else {
             polyName = interfaceScope.declareName(mangleNameForPoly(x), name);
           }
@@ -3529,6 +3535,15 @@
     return StringInterner.get().intern(sb.toString());
   }
 
+  String mangleNameForJsProperty(JMethod x) {
+    assert x.isJsProperty();
+    StringBuilder sb = new StringBuilder();
+    sb.append("jsproperty$");
+    sb.append(getNameString(x));
+    constructManglingSignature(x, sb);
+    return StringInterner.get().intern(sb.toString());
+  }
+
   private static void constructManglingSignature(JMethod x, StringBuilder partialSignature) {
     partialSignature.append("__");
     for (int i = 0; i < x.getOriginalParamTypes().size(); ++i) {
diff --git a/dev/core/src/com/google/gwt/dev/jjs/impl/JsInteropRestrictionChecker.java b/dev/core/src/com/google/gwt/dev/jjs/impl/JsInteropRestrictionChecker.java
new file mode 100644
index 0000000..0ac9629
--- /dev/null
+++ b/dev/core/src/com/google/gwt/dev/jjs/impl/JsInteropRestrictionChecker.java
@@ -0,0 +1,145 @@
+/*
+ * Copyright 2015 Google Inc.
+ * 
+ * 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.gwt.dev.jjs.impl;
+
+import com.google.gwt.core.ext.TreeLogger;
+import com.google.gwt.core.ext.UnableToCompleteException;
+import com.google.gwt.dev.MinimalRebuildCache;
+import com.google.gwt.dev.jjs.InternalCompilerException;
+import com.google.gwt.dev.jjs.ast.Context;
+import com.google.gwt.dev.jjs.ast.JDeclaredType;
+import com.google.gwt.dev.jjs.ast.JField;
+import com.google.gwt.dev.jjs.ast.JMethod;
+import com.google.gwt.dev.jjs.ast.JProgram;
+import com.google.gwt.dev.jjs.ast.JVisitor;
+
+/**
+ * Checks and throws errors for invalid JsInterop constructs.
+ */
+// TODO: prevent the existence of more than 1 (x/is/get/has) getter for the same property name.
+// TODO: handle custom JsType field/method names when that feature exists.
+// TODO: prevent regular Java JsType (not JsProperty) method names like ".x()" colliding with raw JS
+// property names like ".x".
+public class JsInteropRestrictionChecker extends JVisitor {
+
+  public static void exec(TreeLogger logger, JProgram jprogram,
+      MinimalRebuildCache minimalRebuildCache) throws UnableToCompleteException {
+    JsInteropRestrictionChecker jsInteropRestrictionChecker =
+        new JsInteropRestrictionChecker(logger, jprogram, minimalRebuildCache);
+    try {
+      jsInteropRestrictionChecker.accept(jprogram);
+    } catch (InternalCompilerException e) {
+      // Already logged.
+      throw new UnableToCompleteException();
+    }
+  }
+
+  private JDeclaredType currentType;
+  private final JProgram jprogram;
+  private final TreeLogger logger;
+  private final MinimalRebuildCache minimalRebuildCache;
+
+  public JsInteropRestrictionChecker(TreeLogger logger, JProgram jprogram,
+      MinimalRebuildCache minimalRebuildCache) {
+    this.logger = logger;
+    this.jprogram = jprogram;
+    this.minimalRebuildCache = minimalRebuildCache;
+  }
+
+  @Override
+  public void endVisit(JDeclaredType x, Context ctx) {
+    assert currentType == x;
+    currentType = null;
+  }
+
+  @Override
+  public boolean visit(JDeclaredType x, Context ctx) {
+    assert currentType == null;
+    minimalRebuildCache.removeJsInteropNames(x.getName());
+    currentType = x;
+
+    return true;
+  }
+
+  @Override
+  public boolean visit(JField x, Context ctx) {
+    if (jprogram.typeOracle.isExportedField(x)) {
+      boolean success = minimalRebuildCache.addExportedGlobalName(x.getQualifiedExportName(),
+          currentType.getName());
+      if (!success) {
+        logger.log(TreeLogger.ERROR, String.format(
+            "Static field '%s' can't be exported because the global name '%s' is already taken.",
+            computeReadableSignature(x), x.getQualifiedExportName()));
+        throw new UnsupportedOperationException();
+      }
+    } else if (jprogram.typeOracle.isJsTypeField(x)) {
+      boolean success = minimalRebuildCache.addJsTypeMemberName(x.getName(), currentType.getName());
+      if (!success) {
+        logger.log(TreeLogger.ERROR, String.format(
+            "Instance field '%s' can't be exported because the member name '%s' is already taken.",
+            computeReadableSignature(x), x.getName()));
+        throw new UnsupportedOperationException();
+      }
+    }
+
+    return true;
+  }
+
+  @Override
+  public boolean visit(JMethod x, Context ctx) {
+    if (jprogram.typeOracle.isExportedMethod(x)) {
+      boolean success = minimalRebuildCache.addExportedGlobalName(x.getQualifiedExportName(),
+          currentType.getName());
+      if (!success) {
+        logger.log(TreeLogger.ERROR, String.format(
+            "Static method '%s' can't be exported because the global name '%s' is already taken.",
+            computeReadableSignature(x), x.getQualifiedExportName()));
+        throw new UnsupportedOperationException();
+      }
+    } else if (jprogram.typeOracle.isJsTypeMethod(x) && isDirectOrTransitiveJsProperty(x)) {
+      // JsProperty methods are mangled and obfuscated and so do not consume an unobfuscated
+      // collidable name slot.
+    } else if (jprogram.typeOracle.isJsTypeMethod(x)) {
+      boolean success = minimalRebuildCache.addJsTypeMemberName(x.getName(), currentType.getName());
+      if (!success) {
+        logger.log(TreeLogger.ERROR, String.format(
+            "Instance method '%s' can't be exported because the member name '%s' is already taken.",
+            computeReadableSignature(x), x.getName()));
+        throw new UnsupportedOperationException();
+      }
+    }
+
+    return true;
+  }
+
+  private String computeReadableSignature(JField field) {
+    return field.getEnclosingType().getName() + "." + field.getName();
+  }
+
+  private String computeReadableSignature(JMethod method) {
+    return method.getEnclosingType().getName() + "." + method.getName();
+  }
+
+  private boolean isDirectOrTransitiveJsProperty(JMethod method) {
+    if (method.isJsProperty()) {
+      return true;
+    }
+    for (JMethod overrideMethod : method.getOverriddenMethods()) {
+      if (overrideMethod.isJsProperty()) {
+        return true;
+      }
+    }
+    return false;
+  }
+}
diff --git a/dev/core/test/com/google/gwt/dev/CompilerTest.java b/dev/core/test/com/google/gwt/dev/CompilerTest.java
index 4024d40..5397aab 100644
--- a/dev/core/test/com/google/gwt/dev/CompilerTest.java
+++ b/dev/core/test/com/google/gwt/dev/CompilerTest.java
@@ -141,6 +141,31 @@
           "  }",
           "}");
 
+  private MockJavaResource simpleDialogResourceWithExport =
+      JavaResourceBase.createMockJavaResource("com.foo.SimpleDialog",
+          "package com.foo;",
+          "import com.google.gwt.core.client.js.JsExport;",
+          "public class SimpleDialog {",
+          "  @JsExport(\"show\")",
+          "  public static void show() {}",
+          "}");
+
+  private MockJavaResource complexDialogResourceWithExport =
+      JavaResourceBase.createMockJavaResource("com.foo.ComplexDialog",
+          "package com.foo;",
+          "import com.google.gwt.core.client.js.JsExport;",
+          "public class ComplexDialog {",
+          "  @JsExport(\"show\")",
+          "  public static void show() {}",
+          "}");
+
+  private MockJavaResource complexDialogResourceSansExport =
+      JavaResourceBase.createMockJavaResource("com.foo.ComplexDialog",
+          "package com.foo;",
+          "public class ComplexDialog {",
+          "  public static void show() {}",
+          "}");
+
   private MockJavaResource simpleModelEntryPointResource =
       JavaResourceBase.createMockJavaResource("com.foo.TestEntryPoint",
           "package com.foo;",
@@ -461,6 +486,18 @@
           "  }",
           "}");
 
+  private MockJavaResource dialogEntryPointResource =
+      JavaResourceBase.createMockJavaResource("com.foo.TestEntryPoint",
+          "package com.foo;",
+          "import com.google.gwt.core.client.EntryPoint;",
+          "public class TestEntryPoint implements EntryPoint {",
+          "  @Override",
+          "  public void onModuleLoad() {",
+          "    SimpleDialog simpleDialog = new SimpleDialog();",
+          "    ComplexDialog complexDialog = new ComplexDialog();",
+          "  }",
+          "}");
+
   private MockJavaResource brokenGwtCreateEntryPointResource =
       JavaResourceBase.createMockJavaResource("com.foo.TestEntryPoint",
           "package com.foo;",
@@ -911,6 +948,33 @@
         new MinimalRebuildCache(), emptySet, JsOutputOption.PRETTY);
   }
 
+  public void testJsInteropNameCollision() throws Exception {
+    MinimalRebuildCache minimalRebuildCache = new MinimalRebuildCache();
+    File applicationDir = Files.createTempDir();
+    CompilerOptions compilerOptions = new CompilerOptionsImpl();
+    compilerOptions.setJsInteropMode(OptionJsInteropMode.Mode.JS);
+
+    // Simple compile with one dialog.alert() export succeeds.
+    compileToJs(compilerOptions, applicationDir, "com.foo.SimpleModule", Lists.newArrayList(
+        simpleModuleResource, dialogEntryPointResource, simpleDialogResourceWithExport,
+        complexDialogResourceSansExport), minimalRebuildCache, emptySet, JsOutputOption.PRETTY);
+
+    try {
+      // Exporting a second dialog.alert() fails with an exported name collision.
+      compileToJs(compilerOptions, applicationDir, "com.foo.SimpleModule",
+          Lists.<MockResource> newArrayList(complexDialogResourceWithExport), minimalRebuildCache,
+          emptySet, JsOutputOption.PRETTY);
+      fail("Compile should have failed");
+    } catch (UnableToCompleteException e) {
+      // success
+    }
+
+    // Reverting to just a single dialog.alert() starts succeeding again.
+    compileToJs(compilerOptions, applicationDir, "com.foo.SimpleModule",
+        Lists.<MockResource> newArrayList(complexDialogResourceSansExport), minimalRebuildCache,
+        stringSet("com.foo.ComplexDialog", "com.foo.TestEntryPoint"), JsOutputOption.PRETTY);
+  }
+
   public void testGwtCreateJsoRebindResult() throws Exception {
     try {
       compileToJs(Files.createTempDir(), "com.foo.SimpleModule",
diff --git a/dev/core/test/com/google/gwt/dev/MinimalRebuildCacheManagerTest.java b/dev/core/test/com/google/gwt/dev/MinimalRebuildCacheManagerTest.java
index bb3fed6..7b9d0b6 100644
--- a/dev/core/test/com/google/gwt/dev/MinimalRebuildCacheManagerTest.java
+++ b/dev/core/test/com/google/gwt/dev/MinimalRebuildCacheManagerTest.java
@@ -86,6 +86,8 @@
     startingCache.computeReachableTypeNames();
     startingCache.computeAndClearStaleTypesCache(TreeLogger.NULL,
         new JTypeOracle(null, startingCache, true));
+    startingCache.addExportedGlobalName("alert", "Window");
+    startingCache.addJsTypeMemberName("length", "String");
 
     // Save and reload the cache.
     minimalRebuildCacheManager.putCache(moduleName, permutationDescription, startingCache);
diff --git a/dev/core/test/com/google/gwt/dev/jjs/impl/JsInteropRestrictionCheckerTest.java b/dev/core/test/com/google/gwt/dev/jjs/impl/JsInteropRestrictionCheckerTest.java
new file mode 100644
index 0000000..46efe15
--- /dev/null
+++ b/dev/core/test/com/google/gwt/dev/jjs/impl/JsInteropRestrictionCheckerTest.java
@@ -0,0 +1,143 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * 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.gwt.dev.jjs.impl;
+
+import com.google.gwt.core.ext.TreeLogger;
+import com.google.gwt.core.ext.UnableToCompleteException;
+import com.google.gwt.dev.MinimalRebuildCache;
+import com.google.gwt.dev.jjs.ast.JMethod;
+import com.google.gwt.dev.jjs.ast.JProgram;
+
+/**
+ * Tests for the JsInteropRestrictionChecker.
+ */
+public class JsInteropRestrictionCheckerTest extends OptimizerTestBase {
+
+  public void testCollidingFieldExportsFails() throws Exception {
+    addSnippetImport("com.google.gwt.core.client.js.JsExport");
+    addSnippetClassDecl(
+        "public static class Buggy {",
+        "  @JsExport(\"show\")",
+        "  public static final int show = 0;",
+        "  @JsExport(\"show\")",
+        "  public static final int display = 0;",
+        "}");
+
+    assertCompileFails();
+  }
+
+  public void testCollidingJsTypeJsPropertiesSucceeds() throws Exception {
+    addSnippetImport("com.google.gwt.core.client.js.JsType");
+    addSnippetImport("com.google.gwt.core.client.js.JsProperty");
+    addSnippetClassDecl(
+        "@JsType",
+        "public static interface IBuggy {",
+        "  @JsProperty",
+        "  int x();",
+        "  @JsProperty",
+        "  void x(int x);",
+        "}",
+        "public static class Buggy implements IBuggy {",
+        "  public int x() {return 0;}",
+        "  public void x(int x) {}",
+        "}");
+
+    assertCompileSucceeds();
+  }
+
+  public void testCollidingMethodExportsFails() throws Exception {
+    addSnippetImport("com.google.gwt.core.client.js.JsExport");
+    addSnippetClassDecl(
+        "public static class Buggy {",
+        "  @JsExport(\"show\")",
+        "  public static void show() {}",
+        "  @JsExport(\"show\")",
+        "  public static void display() {}",
+        "}");
+
+    assertCompileFails();
+  }
+
+  public void testCollidingMethodToFieldExportsFails() throws Exception {
+    addSnippetImport("com.google.gwt.core.client.js.JsExport");
+    addSnippetClassDecl(
+        "public static class Buggy {",
+        "  @JsExport(\"show\")",
+        "  public static void show() {}",
+        "  @JsExport(\"show\")",
+        "  public static final int display = 0;",
+        "}");
+
+    assertCompileFails();
+  }
+
+  public void testCollidingMethodToFieldJsTypeFails() throws Exception {
+    addSnippetImport("com.google.gwt.core.client.js.JsType");
+    addSnippetClassDecl(
+        "@JsType",
+        "public static class Buggy {",
+        "  public void show() {}",
+        "  public final int show = 0;",
+        "}");
+
+    assertCompileFails();
+  }
+
+  public void testSingleExportSucceeds() throws Exception {
+    addSnippetImport("com.google.gwt.core.client.js.JsExport");
+    addSnippetClassDecl(
+        "public static class Buggy {",
+        "  @JsExport(\"show\")",
+        "  public static void show() {}",
+        "}");
+
+    assertCompileSucceeds();
+  }
+
+  public void testSingleJsTypeSucceeds() throws Exception {
+    addSnippetImport("com.google.gwt.core.client.js.JsType");
+    addSnippetClassDecl(
+        "@JsType",
+        "public static class Buggy {",
+        "  public void show() {}",
+        "}");
+
+    assertCompileSucceeds();
+  }
+
+  @Override
+  protected boolean optimizeMethod(JProgram program, JMethod method) {
+    try {
+      JsInteropRestrictionChecker.exec(TreeLogger.NULL, program, new MinimalRebuildCache());
+    } catch (UnableToCompleteException e) {
+      throw new RuntimeException(e);
+    }
+    return false;
+  }
+
+  private void assertCompileFails() {
+    try {
+      optimize("void", "new Buggy();");
+      fail("JsInteropRestrictionCheckerTest should have prevented the name collision.");
+    } catch (Exception e) {
+      assertTrue(e.getCause() instanceof UnableToCompleteException);
+    }
+  }
+
+  private void assertCompileSucceeds() throws UnableToCompleteException {
+    optimize("void", "new Buggy();");
+  }
+}
diff --git a/user/test/com/google/gwt/core/client/interop/MyJsInterface.java b/user/test/com/google/gwt/core/client/interop/MyJsInterface.java
index 0287333..64d7412 100644
--- a/user/test/com/google/gwt/core/client/interop/MyJsInterface.java
+++ b/user/test/com/google/gwt/core/client/interop/MyJsInterface.java
@@ -25,7 +25,8 @@
   @JsProperty
   int x();
 
-  @JsProperty MyJsInterface x(int a);
+  @JsProperty
+  MyJsInterface x(int a);
 
   @JsProperty
   int getY();