Disable invalid argument count to formals check

Bug: 214509535
Change-Id: I25b2cfd3bd2d7417760d7e8c3ba5cefc6eff884e
diff --git a/src/main/java/com/android/tools/r8/shaking/VerticalClassMerger.java b/src/main/java/com/android/tools/r8/shaking/VerticalClassMerger.java
index c882cf4..a7362e5 100644
--- a/src/main/java/com/android/tools/r8/shaking/VerticalClassMerger.java
+++ b/src/main/java/com/android/tools/r8/shaking/VerticalClassMerger.java
@@ -1335,7 +1335,8 @@
       }
       List<FormalTypeParameter> formals = source.getClassSignature().getFormalTypeParameters();
       if (genericArgumentsToSuperType.size() != formals.size()) {
-        assert false : "Invalid argument count to formals";
+        // TODO(b/214509535): Correctly rewrite signature when type arguments is empty.
+        assert genericArgumentsToSuperType.isEmpty() : "Invalid argument count to formals";
         return null;
       }
       Map<String, FieldTypeSignature> substitutionMap = new HashMap<>();
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergingWithMissingTypeArgsTest.java b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergingWithMissingTypeArgsTest.java
new file mode 100644
index 0000000..00d8557
--- /dev/null
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergingWithMissingTypeArgsTest.java
@@ -0,0 +1,60 @@
+// Copyright (c) 2022, 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.classmerging.vertical;
+
+import com.android.tools.r8.NeverInline;
+import com.android.tools.r8.TestBase;
+import com.android.tools.r8.TestParameters;
+import com.android.tools.r8.TestParametersCollection;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameter;
+import org.junit.runners.Parameterized.Parameters;
+
+@RunWith(Parameterized.class)
+public class VerticalClassMergingWithMissingTypeArgsTest extends TestBase {
+
+  @Parameter(0)
+  public TestParameters parameters;
+
+  @Parameters(name = "{0}")
+  public static TestParametersCollection data() {
+    return getTestParameters().withAllRuntimesAndApiLevels().build();
+  }
+
+  @Test
+  public void test() throws Exception {
+    testForR8Compat(parameters.getBackend())
+        .addInnerClasses(getClass())
+        .addKeepMainRule(Main.class)
+        .addKeepAttributes("Signature, InnerClasses, EnclosingMethod, *Annotation*")
+        .addVerticallyMergedClassesInspector(
+            inspector -> inspector.assertMergedIntoSubtype(A.class))
+        .enableInliningAnnotations()
+        .setMinApi(parameters.getApiLevel())
+        .compile()
+        .run(parameters.getRuntime(), Main.class)
+        .assertSuccessWithOutputLines("B.m()");
+  }
+
+  static class Main {
+
+    public static void main(String[] args) {
+      new B().m();
+    }
+  }
+
+  static class A<T> {}
+
+  interface I<T> {}
+
+  static class B extends A implements I<B> {
+    @NeverInline
+    void m() {
+      System.out.println("B.m()");
+    }
+  }
+}