Introduce InterfaceDesugaringForTesting

The move to R8 cf to cf desugaring requires
lots of changes and this will allow to move the
methods and variables used in tests without XXL CLs

Bug: 191656218
Change-Id: I9f41bf59f0e99caf4b1fa43b2284f4e41874dc8e
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceDesugaringForTesting.java b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceDesugaringForTesting.java
new file mode 100644
index 0000000..81ec904
--- /dev/null
+++ b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceDesugaringForTesting.java
@@ -0,0 +1,28 @@
+// Copyright (c) 2021, the R8 project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+package com.android.tools.r8.ir.desugar.itf;
+
+public class InterfaceDesugaringForTesting {
+
+  public static String getEmulateLibraryClassNameSuffix() {
+    return InterfaceMethodRewriter.EMULATE_LIBRARY_CLASS_NAME_SUFFIX;
+  }
+
+  public static String getCompanionClassNameSuffix() {
+    return InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+  }
+
+  public static String getDefaultMethodPrefix() {
+    return InterfaceMethodRewriter.DEFAULT_METHOD_PREFIX;
+  }
+
+  public static String getPrivateMethodPrefix() {
+    return InterfaceMethodRewriter.PRIVATE_METHOD_PREFIX;
+  }
+
+  public static String getCompanionClassDescriptor(String descriptor) {
+    return InterfaceMethodRewriter.getCompanionClassDescriptor(descriptor);
+  }
+}
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriter.java b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriter.java
index 6c47058..3e93691 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriter.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriter.java
@@ -120,11 +120,11 @@
 //
 public final class InterfaceMethodRewriter implements CfInstructionDesugaring {
 
-  // Public for testing.
-  public static final String EMULATE_LIBRARY_CLASS_NAME_SUFFIX = "$-EL";
-  public static final String COMPANION_CLASS_NAME_SUFFIX = "$-CC";
-  public static final String DEFAULT_METHOD_PREFIX = "$default$";
-  public static final String PRIVATE_METHOD_PREFIX = "$private$";
+  // Use InterfaceDesugaringForTesting for public accesses in tests.
+  static final String EMULATE_LIBRARY_CLASS_NAME_SUFFIX = "$-EL";
+  static final String COMPANION_CLASS_NAME_SUFFIX = "$-CC";
+  static final String DEFAULT_METHOD_PREFIX = "$default$";
+  static final String PRIVATE_METHOD_PREFIX = "$private$";
 
   private final AppView<?> appView;
   private final InternalOptions options;
@@ -1155,7 +1155,8 @@
     }
   }
 
-  public static String getCompanionClassDescriptor(String descriptor) {
+  // Use InterfaceDesugaringForTesting for public accesses in tests.
+  static String getCompanionClassDescriptor(String descriptor) {
     return descriptor.substring(0, descriptor.length() - 1) + COMPANION_CLASS_NAME_SUFFIX + ";";
   }
 
diff --git a/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java b/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java
index f13a704..dfebfd7 100644
--- a/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java
+++ b/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java
@@ -4,6 +4,7 @@
 
 package com.android.tools.r8;
 
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
 import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
 import static org.junit.Assert.assertEquals;
 
@@ -13,7 +14,6 @@
 import com.android.tools.r8.errors.InternalCompilerError;
 import com.android.tools.r8.errors.Unimplemented;
 import com.android.tools.r8.errors.Unreachable;
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
@@ -97,7 +97,7 @@
           // interface, the main class/interface, or for JDK9, desugaring of try-with-resources.
           ClassReference reference = Reference.classFromDescriptor(descriptor);
           Assert.assertTrue(
-              descriptor.endsWith(InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX + ";")
+              descriptor.endsWith(getCompanionClassNameSuffix() + ";")
                   || SyntheticItemsTestUtils.isExternalTwrCloseMethod(reference)
                   || SyntheticItemsTestUtils.isExternalLambda(reference)
                   || SyntheticItemsTestUtils.isExternalStaticInterfaceCall(reference)
diff --git a/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java b/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java
index fd7a3bd..a20964a 100644
--- a/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java
+++ b/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java
@@ -4,6 +4,8 @@
 
 package com.android.tools.r8;
 
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getPrivateMethodPrefix;
 import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
 import static com.android.tools.r8.utils.FileUtils.ZIP_EXTENSION;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
@@ -13,7 +15,6 @@
 import static org.junit.Assume.assumeFalse;
 
 import com.android.tools.r8.ToolHelper.DexVm;
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.TestDescriptionWatcher;
@@ -218,21 +219,24 @@
   public void desugaredPrivateInterfaceMethods() throws Throwable {
     assumeFalse("CF backend does not desugar", this instanceof R8CFRunExamplesJava9Test);
     final String iName = "privateinterfacemethods.I";
-    test("desugared-private-interface-methods",
-        "privateinterfacemethods", "PrivateInterfaceMethods")
+    test(
+            "desugared-private-interface-methods",
+            "privateinterfacemethods",
+            "PrivateInterfaceMethods")
         .withMinApiLevel(AndroidApiLevel.M.getLevel())
         .withKeepAll()
-        .withDexCheck(dexInspector -> {
-          ClassSubject companion = dexInspector.clazz(
-              iName + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX);
-          assertThat(companion, isPresent());
-          MethodSubject iFoo = companion.method(
-              "java.lang.String",
-              InterfaceMethodRewriter.PRIVATE_METHOD_PREFIX + "iFoo",
-              ImmutableList.of(iName, "boolean"));
-          assertThat(iFoo, isPresent());
-          assertTrue(iFoo.getMethod().isPublicMethod());
-        })
+        .withDexCheck(
+            dexInspector -> {
+              ClassSubject companion = dexInspector.clazz(iName + getCompanionClassNameSuffix());
+              assertThat(companion, isPresent());
+              MethodSubject iFoo =
+                  companion.method(
+                      "java.lang.String",
+                      getPrivateMethodPrefix() + "iFoo",
+                      ImmutableList.of(iName, "boolean"));
+              assertThat(iFoo, isPresent());
+              assertTrue(iFoo.getMethod().isPublicMethod());
+            })
         .run();
   }
 
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerDebugTestRunner.java b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerDebugTestRunner.java
index 210967c..8709781 100644
--- a/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerDebugTestRunner.java
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerDebugTestRunner.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.classmerging.vertical;
 
-import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.not;
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -52,7 +52,7 @@
     // applied) contain "$classmerging$.
     String qualifiedMethodSignature =
         state.getClassSignature() + "->" + state.getMethodName() + state.getMethodSignature();
-    boolean holderIsCompanionClass = state.getClassName().endsWith(COMPANION_CLASS_NAME_SUFFIX);
+    boolean holderIsCompanionClass = state.getClassName().endsWith(getCompanionClassNameSuffix());
     if (!holderIsCompanionClass) {
       assertThat(qualifiedMethodSignature, not(containsString("$classmerging$")));
     }
diff --git a/src/test/java/com/android/tools/r8/debug/InterfaceMethodTest.java b/src/test/java/com/android/tools/r8/debug/InterfaceMethodTest.java
index 5f4be39..927b5ba 100644
--- a/src/test/java/com/android/tools/r8/debug/InterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/debug/InterfaceMethodTest.java
@@ -4,10 +4,12 @@
 
 package com.android.tools.r8.debug;
 
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getDefaultMethodPrefix;
 import static org.junit.Assert.assertEquals;
 
 import com.android.tools.r8.debug.DebugTestBase.JUnit3Wrapper.Command;
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -52,12 +54,12 @@
       defaultMethodName = "doSomething";
       defaultMethodThisName = "this";
     } else {
-      defaultMethodContainerClass = "InterfaceWithDefaultAndStaticMethods"
-          + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+      defaultMethodContainerClass =
+          "InterfaceWithDefaultAndStaticMethods" + getCompanionClassNameSuffix();
       // IntelliJ's debugger does not know about the companion class. The only way to match it with
       // the source file or the desguared interface is to make it an inner class.
-      assertEquals('$', InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX.charAt(0));
-      defaultMethodName = InterfaceMethodRewriter.DEFAULT_METHOD_PREFIX + "doSomething";
+      assertEquals('$', getCompanionClassNameSuffix().charAt(0));
+      defaultMethodName = getDefaultMethodPrefix() + "doSomething";
       defaultMethodThisName = "_this";
     }
 
@@ -121,8 +123,9 @@
     if (supportsDefaultMethod(config)) {
       staticMethodContainerClass = "InterfaceWithDefaultAndStaticMethods";
     } else {
-      staticMethodContainerClass = "InterfaceWithDefaultAndStaticMethods"
-          + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+      staticMethodContainerClass =
+          "InterfaceWithDefaultAndStaticMethods"
+              + InterfaceDesugaringForTesting.getCompanionClassNameSuffix();
     }
 
     List<Command> commands = new ArrayList<>();
diff --git a/src/test/java/com/android/tools/r8/desugar/DesugarInnerClassesInInterfaces.java b/src/test/java/com/android/tools/r8/desugar/DesugarInnerClassesInInterfaces.java
index 2d396f7d..1c8d5b9 100644
--- a/src/test/java/com/android/tools/r8/desugar/DesugarInnerClassesInInterfaces.java
+++ b/src/test/java/com/android/tools/r8/desugar/DesugarInnerClassesInInterfaces.java
@@ -3,11 +3,12 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.desugar;
 
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
+
 import com.android.tools.r8.DesugarTestConfiguration;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.concurrent.Callable;
@@ -24,16 +25,16 @@
 
   private final List<String> EXPECTED_RESULT_WITH_DESUGARING =
       ImmutableList.of(
-          WithAnonymousInner.class.getName() + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX,
+          WithAnonymousInner.class.getName() + getCompanionClassNameSuffix(),
           "true",
-          WithLocalInner.class.getName() + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX,
+          WithLocalInner.class.getName() + getCompanionClassNameSuffix(),
           "true");
 
   private final List<String> EXPECTED_RESULT_WITH_DESUGARING_B168697955 =
       ImmutableList.of(
-          WithAnonymousInner.class.getName() + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX,
+          WithAnonymousInner.class.getName() + getCompanionClassNameSuffix(),
           "false",
-          WithLocalInner.class.getName() + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX,
+          WithLocalInner.class.getName() + getCompanionClassNameSuffix(),
           "false");
 
   @Parameterized.Parameters(name = "{0}")
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/EmulatedInterfacesTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/EmulatedInterfacesTest.java
index 4e96f57..b3d3ddd 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/EmulatedInterfacesTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/EmulatedInterfacesTest.java
@@ -4,6 +4,7 @@
 
 package com.android.tools.r8.desugar.desugaredlibrary;
 
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getEmulateLibraryClassNameSuffix;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
 import static junit.framework.TestCase.assertEquals;
 import static junit.framework.TestCase.assertTrue;
@@ -14,7 +15,6 @@
 import com.android.tools.r8.code.Instruction;
 import com.android.tools.r8.graph.DexClass;
 import com.android.tools.r8.graph.DexEncodedMethod;
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.utils.BooleanUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
@@ -75,11 +75,7 @@
 
   private List<FoundClassSubject> getEmulatedInterfaces(CodeInspector inspector) {
     return inspector.allClasses().stream()
-        .filter(
-            clazz ->
-                clazz
-                    .getOriginalName()
-                    .contains(InterfaceMethodRewriter.EMULATE_LIBRARY_CLASS_NAME_SUFFIX))
+        .filter(clazz -> clazz.getOriginalName().contains(getEmulateLibraryClassNameSuffix()))
         .collect(Collectors.toList());
   }
 
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineFromStaticInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineFromStaticInterfaceMethodTest.java
index 5660355..e1763f1 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineFromStaticInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineFromStaticInterfaceMethodTest.java
@@ -3,6 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.ir.optimize.outliner;
 
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertEquals;
@@ -12,7 +13,6 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
@@ -65,8 +65,7 @@
                     .getApiLevel()
                     .isGreaterThanOrEqualTo(apiLevelWithStaticInterfaceMethodsSupport())
             ? inspector.clazz(I.class)
-            : inspector.clazz(
-                I.class.getTypeName() + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX);
+            : inspector.clazz(I.class.getTypeName() + getCompanionClassNameSuffix());
     assertThat(interfaceSubject, isPresent());
 
     MethodSubject greetMethodSubject = interfaceSubject.uniqueMethodWithName("greet");
diff --git a/src/test/java/com/android/tools/r8/jasmin/AnnotationCompanionClassTest.java b/src/test/java/com/android/tools/r8/jasmin/AnnotationCompanionClassTest.java
index 2875a43..36a35e5 100644
--- a/src/test/java/com/android/tools/r8/jasmin/AnnotationCompanionClassTest.java
+++ b/src/test/java/com/android/tools/r8/jasmin/AnnotationCompanionClassTest.java
@@ -3,11 +3,11 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.jasmin;
 
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertFalse;
 
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
@@ -37,8 +37,7 @@
     AndroidApp androidApp = compileWithD8(builder);
 
     CodeInspector codeInspector = new CodeInspector(androidApp);
-    ClassSubject clazz =
-        codeInspector.clazz("MyAnnotation" + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX);
+    ClassSubject clazz = codeInspector.clazz("MyAnnotation" + getCompanionClassNameSuffix());
     assertThat(clazz, isPresent());
     assertFalse(clazz.isAnnotation());
   }
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java
index cae1185..1868602 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.StringUtils;
@@ -84,9 +84,11 @@
     assertTrue(inspector.clazz(LibraryInterface.class).isPresent());
     assertTrue(inspector.method(LibraryInterface.class.getMethod("foo")).isPresent());
     if (willDesugarDefaultInterfaceMethods(parameters.getApiLevel())) {
-      ClassSubject companion = inspector.clazz(Reference.classFromDescriptor(
-          InterfaceMethodRewriter.getCompanionClassDescriptor(
-              classFromClass(LibraryInterface.class).getDescriptor())));
+      ClassSubject companion =
+          inspector.clazz(
+              Reference.classFromDescriptor(
+                  InterfaceDesugaringForTesting.getCompanionClassDescriptor(
+                      classFromClass(LibraryInterface.class).getDescriptor())));
       // Check that we included the companion class.
       assertTrue(companion.isPresent());
       // TODO(b/129223905): Check the method is also present on the companion class.
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java b/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java
index 961d400..19b87e4 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.shaking.ifrule.interfacemethoddesugaring;
 
-import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPublic;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isStatic;
@@ -74,7 +74,7 @@
             .inspector();
 
     ClassSubject classSubject =
-        inspector.clazz(Interface.class.getTypeName() + COMPANION_CLASS_NAME_SUFFIX);
+        inspector.clazz(Interface.class.getTypeName() + getCompanionClassNameSuffix());
     assertThat(classSubject, isPresent());
     assertEquals(2, classSubject.allMethods().size());
 
diff --git a/src/test/java/com/android/tools/r8/synthesis/SyntheticItemsTestUtils.java b/src/test/java/com/android/tools/r8/synthesis/SyntheticItemsTestUtils.java
index 1b4ec31..6ffbce9 100644
--- a/src/test/java/com/android/tools/r8/synthesis/SyntheticItemsTestUtils.java
+++ b/src/test/java/com/android/tools/r8/synthesis/SyntheticItemsTestUtils.java
@@ -5,7 +5,7 @@
 
 import static org.hamcrest.CoreMatchers.containsString;
 
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
@@ -22,7 +22,7 @@
 
   public static ClassReference syntheticCompanionClass(Class<?> clazz) {
     return Reference.classFromDescriptor(
-        InterfaceMethodRewriter.getCompanionClassDescriptor(
+        InterfaceDesugaringForTesting.getCompanionClassDescriptor(
             Reference.classFromClass(clazz).getDescriptor()));
   }
 
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/ClassSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/ClassSubject.java
index 4f8ecd3..8beec8a 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/ClassSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/ClassSubject.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.utils.codeinspector;
 
-import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
 
 import com.android.tools.r8.graph.ClassAccessFlags;
 import com.android.tools.r8.graph.DexMethod;
@@ -232,7 +232,9 @@
     String descriptor = reference.getDescriptor();
     return codeInspector.clazz(
         Reference.classFromDescriptor(
-            descriptor.substring(0, descriptor.length() - 1) + COMPANION_CLASS_NAME_SUFFIX + ";"));
+            descriptor.substring(0, descriptor.length() - 1)
+                + getCompanionClassNameSuffix()
+                + ";"));
   }
 
   public abstract RetraceClassResult retrace();
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java b/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java
index 0533c6b..77c68b3 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java
@@ -3,6 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils.codeinspector;
 
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
+
 import com.android.tools.r8.DexIndexedConsumer;
 import com.android.tools.r8.StringResource;
 import com.android.tools.r8.TestDiagnosticMessagesImpl;
@@ -24,7 +26,6 @@
 import com.android.tools.r8.graph.DexItemFactory;
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.ir.conversion.SwitchPayloadResolver;
-import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.ClassNamingForNameMapper;
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
@@ -327,9 +328,7 @@
   }
 
   public ClassSubject companionClassFor(Class<?> clazz) {
-    return clazz(
-        Reference.classFromTypeName(
-            clazz.getTypeName() + InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX));
+    return clazz(Reference.classFromTypeName(clazz.getTypeName() + getCompanionClassNameSuffix()));
   }
 
   public void forAllClasses(Consumer<FoundClassSubject> inspection) {
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
index 268c51a..d781ef5 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.utils.codeinspector;
 
-import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.DEFAULT_METHOD_PREFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getDefaultMethodPrefix;
 
 import com.android.tools.r8.cf.code.CfInstruction;
 import com.android.tools.r8.cf.code.CfPosition;
@@ -372,7 +372,7 @@
             .build();
     return companionClass.method(
         reference.getReturnType().getTypeName(),
-        DEFAULT_METHOD_PREFIX + reference.getMethodName(),
+        getDefaultMethodPrefix() + reference.getMethodName(),
         p);
   }
 }