Improves EXPECT_DEATH_IF_SUPPORTED to allow streaming of messages and enforcing the validity of arguments (by Vlad Losev); adds samples for the event listener API (by Vlad Losev); simplifies the tests using EXPECT_DEATH_IF_SUPPORTED (by Zhanyong Wan).

include/gtest/gtest-death-test.h

@@ -260,7 +260,7 @@ class KilledBySignal {
 
 // EXPECT_DEATH_IF_SUPPORTED(statement, regex) and
 // ASSERT_DEATH_IF_SUPPORTED(statement, regex) expand to real death tests if
-// death tests are supported; otherwise they expand to empty.  This is
+// death tests are supported; otherwise they just issue a warning.  This is
 // useful when you are combining death test assertions with normal test
 // assertions in one test.
 #if GTEST_HAS_DEATH_TEST
@@ -270,13 +270,9 @@ class KilledBySignal {
     ASSERT_DEATH(statement, regex)
 #else
 #define EXPECT_DEATH_IF_SUPPORTED(statement, regex) \
-    GTEST_LOG_(WARNING, \
-               "Death tests are not supported on this platform. The statement" \
-               " '" #statement "' can not be verified")
+    GTEST_UNSUPPORTED_DEATH_TEST_(statement, regex, )
 #define ASSERT_DEATH_IF_SUPPORTED(statement, regex) \
-    GTEST_LOG_(WARNING, \
-               "Death tests are not supported on this platform. The statement" \
-               " '" #statement "' can not be verified")
+    GTEST_UNSUPPORTED_DEATH_TEST_(statement, regex, return)
 #endif
 
 }  // namespace testing

include/gtest/internal/gtest-death-test-internal.h

@@ -219,6 +219,55 @@ class InternalRunDeathTestFlag {
 // the flag is specified; otherwise returns NULL.
 InternalRunDeathTestFlag* ParseInternalRunDeathTestFlag();
 
+#else  // GTEST_HAS_DEATH_TEST
+
+// This macro is used for implementing macros such as
+// EXPECT_DEATH_IF_SUPPORTED and ASSERT_DEATH_IF_SUPPORTED on systems where
+// death tests are not supported. Those macros must compile on such systems
+// iff EXPECT_DEATH and ASSERT_DEATH compile with the same parameters on
+// systems that support death tests. This allows one to write such a macro
+// on a system that does not support death tests and be sure that it will
+// compile on a death-test supporting system.
+//
+// Parameters:
+//   statement -  A statement that a macro such as EXPECT_DEATH would test
+//                for program termination. This macro has to make sure this
+//                statement is compiled but not executed, to ensure that
+//                EXPECT_DEATH_IF_SUPPORTED compiles with a certain
+//                parameter iff EXPECT_DEATH compiles with it.
+//   regex     -  A regex that a macro such as EXPECT_DEATH would use to test
+//                the output of statement.  This parameter has to be
+//                compiled but not evaluated by this macro, to ensure that
+//                this macro only accepts expressions that a macro such as
+//                EXPECT_DEATH would accept.
+//   terminator - Must be an empty statement for EXPECT_DEATH_IF_SUPPORTED
+//                and a return statement for ASSERT_DEATH_IF_SUPPORTED.
+//                This ensures that ASSERT_DEATH_IF_SUPPORTED will not
+//                compile inside functions where ASSERT_DEATH doesn't
+//                compile.
+//
+//  The branch that has an always false condition is used to ensure that
+//  statement and regex are compiled (and thus syntactically correct) but
+//  never executed. The unreachable code macro protects the terminator
+//  statement from generating an 'unreachable code' warning in case
+//  statement unconditionally returns or throws. The Message constructor at
+//  the end allows the syntax of streaming additional messages into the
+//  macro, for compilational compatibility with EXPECT_DEATH/ASSERT_DEATH.
+//  TODO(vladl@google.com): rename the GTEST_HIDE_UNREACHABLE_CODE_ macro to
+//  GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_.
+#define GTEST_UNSUPPORTED_DEATH_TEST_(statement, regex, terminator) \
+    GTEST_AMBIGUOUS_ELSE_BLOCKER_ \
+    if (::testing::internal::AlwaysTrue()) { \
+      GTEST_LOG_(WARNING, \
+                 "Death tests are not supported on this platform.\n" \
+                 "Statement '" #statement "' cannot be verified."); \
+    } else if (!::testing::internal::AlwaysTrue()) { \
+      ::testing::internal::RE::PartialMatch(".*", (regex)); \
+      GTEST_HIDE_UNREACHABLE_CODE_(statement); \
+      terminator; \
+    } else \
+      ::testing::Message()
+
 #endif  // GTEST_HAS_DEATH_TEST
 
 }  // namespace internal