Mojo: MultiprocessTestHelper: Allow {ASSERT,EXPECT}_...() to be used in child.

mojo/common/test/multiprocess_test_helper.h

Index: mojo/common/test/multiprocess_test_helper.h
diff --git a/mojo/common/test/multiprocess_test_helper.h b/mojo/common/test/multiprocess_test_helper.h
index 103dcf4b7009441efb84fcc8ef62f937a591819e..db5450c8214c151be38baaa5fe9a94f73f12d68d 100644
--- a/mojo/common/test/multiprocess_test_helper.h
+++ b/mojo/common/test/multiprocess_test_helper.h
@@ -29,7 +29,8 @@ class MultiprocessTestHelper {
   ~MultiprocessTestHelper();
 
   // Start a child process and run the "main" function "named" |test_child_name|
-  // declared using |MOJO_MULTIPROCESS_TEST_CHILD_MAIN()| (below).
+  // declared using |MOJO_MULTIPROCESS_TEST_CHILD_MAIN()| or
+  // |MOJO_MULTIPROCESS_TEST_CHILD_TEST()| (below).
   void StartChild(const std::string& test_child_name);
   // Wait for the child process to terminate.
   // Returns the exit code of the child process. Note that, though it's declared
@@ -39,6 +40,12 @@ class MultiprocessTestHelper {
   // 0-127 being preserved, and -1 being outside the range 0-127.
   int WaitForChildShutdown();
 
+  // Like |WaitForChildShutdown()|, but returns true on success (exit code of 0)
+  // and false otherwise. You probably want to do something like
+  // |EXPECT_TRUE(WaitForChildTestShutdown());|. Mainly for use with
+  // |MOJO_MULTIPROCESS_TEST_CHILD_TEST()|.
+  bool WaitForChildTestShutdown();
+
   // For use by |MOJO_MULTIPROCESS_TEST_CHILD_MAIN()| only:
   static void ChildSetup();
 
@@ -65,6 +72,19 @@ class MultiprocessTestHelper {
         test_child_name ## TestChildMain, \
         ::mojo::test::MultiprocessTestHelper::ChildSetup)
 
+// Use this (and |WaitForChildTestShutdown()|) for the child process's "main()",
+// if you want to use |EXPECT_...()| or |ASSERT_...()|; it has a |void| return
+// type. (Note that while an |ASSERT_...()| failure will abort the test in the
+// child, it will not abort the test in the parent.)
+#define MOJO_MULTIPROCESS_TEST_CHILD_TEST(test_child_name) \
+    void test_child_name ## TestChildTest(); \
+    MOJO_MULTIPROCESS_TEST_CHILD_MAIN(test_child_name) { \
+      test_child_name ## TestChildTest(); \
+      return (::testing::Test::HasFatalFailure() || \
+              ::testing::Test::HasNonfatalFailure()) ? 1 : 0; \
+    } \
+    void test_child_name ## TestChildTest()
+
 }  // namespace test
 }  // namespace mojo