Add a test that highlights limitations of lookupSingleInterfaceTarget()

Bug: 145271928, 142116551
Change-Id: I3b75943bc467f1ffc184061385f5ce1d3dfe93b4

src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineFunctionalInterfaceMethodImplementedByLambdasTest.java

diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineFunctionalInterfaceMethodImplementedByLambdasTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineFunctionalInterfaceMethodImplementedByLambdasTest.java
new file mode 100644
index 0000000..ed54346
--- /dev/null
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineFunctionalInterfaceMethodImplementedByLambdasTest.java
@@ -0,0 +1,77 @@
+// Copyright (c) 2019, 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.optimize.inliner;
+
+import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+import com.android.tools.r8.NeverClassInline;
+import com.android.tools.r8.TestBase;
+import com.android.tools.r8.TestParameters;
+import com.android.tools.r8.TestParametersCollection;
+import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+
+@RunWith(Parameterized.class)
+public class InlineFunctionalInterfaceMethodImplementedByLambdasTest extends TestBase {
+
+  private final TestParameters parameters;
+
+  @Parameterized.Parameters(name = "{0}")
+  public static TestParametersCollection data() {
+    return getTestParameters().withAllRuntimesAndApiLevels().build();
+  }
+
+  public InlineFunctionalInterfaceMethodImplementedByLambdasTest(TestParameters parameters) {
+    this.parameters = parameters;
+  }
+
+  @Test
+  public void test() throws Exception {
+    testForR8(parameters.getBackend())
+        .addInnerClasses(InlineFunctionalInterfaceMethodImplementedByLambdasTest.class)
+        .addKeepMainRule(TestClass.class)
+        .enableClassInliningAnnotations()
+        .setMinApi(parameters.getApiLevel())
+        .compile()
+        .inspect(this::inspect)
+        .run(parameters.getRuntime(), TestClass.class)
+        .assertSuccessWithOutputLines("Hello world!");
+  }
+
+  private void inspect(CodeInspector inspector) {
+    if (parameters.isDexRuntime()) {
+      // TODO(b/145271928): Should be able to inline I.m().
+      assertThat(inspector.clazz(I.class), isPresent());
+    }
+
+    // TODO(b/145271928): Should be able to inline A.m().
+    assertThat(inspector.clazz(A.class), isPresent());
+  }
+
+  static class TestClass {
+
+    public static void main(String[] args) {
+      ((I) new A()).m();
+      ((I) () -> System.out.println(" world!")).m();
+    }
+  }
+
+  interface I {
+
+    void m();
+  }
+
+  @NeverClassInline
+  static class A implements I {
+
+    @Override
+    public void m() {
+      System.out.print("Hello");
+    }
+  }
+}