[debuginfo-tests] Add support for moving debuginfo-tests from clang/test to llvm/projects or monorepo.

[hintonda]

Summary

The new version of debuginfo-tests will have it's own
lit.cfg.py file which is incompatible with the one in clang/test.
This change supports both the old and new versions, and can be used
until the bots actually move debuginfo-tests to either clang/test or
the monorepo.

This is a prerequisite for D40971.

cfe/trunk/test/CMakeLists.txt

add_lit_testsuites(CLANG ${CMAKE_CURRENT_SOURCE_DIR}
   PARAMS ${CLANG_TEST_PARAMS}
   DEPENDS ${CLANG_TEST_DEPS}
 )
 
 # Add a legacy target spelling: clang-test
 add_custom_target(clang-test)
 add_dependencies(clang-test check-clang)
 set_target_properties(clang-test PROPERTIES FOLDER "Clang tests")
+
+# FIXME: This logic can be removed once all buildbots have moved
+# debuginfo-test from clang/test to llvm/projects or monorepo.
+if(EXISTS debuginfo-tests)
+  message(WARNING "Including debuginfo-tests in clang/test is deprecated.  Move to llvm/projects or use monorepo.")
+  if(EXISTS debuginfo-tests/CMakeLists.txt)
+    add_subdirectory(debuginfo-tests)
+  endif()
+endif()

cfe/trunk/test/lit.cfg.py

 # For each occurrence of a clang tool name, replace it with the full path to
 # the build directory holding that tool.  We explicitly specify the directories
 # to search to ensure that we get the tools just built and not some random
 # tools that might happen to be in the user's PATH.
 tool_dirs = [config.clang_tools_dir, config.llvm_tools_dir]
 
 tools = [
     'c-index-test', 'clang-check', 'clang-diff', 'clang-format', 'opt',
-    ToolSubst('%test_debuginfo', command=os.path.join(
-        config.llvm_src_root, 'utils', 'test_debuginfo.pl')),
     ToolSubst('%clang_func_map', command=FindTool(
         'clang-func-mapping'), unresolved='ignore'),
 ]
 
+# FIXME: This logic can be removed once all buildbots have moved
+# debuginfo-test from clang/test to llvm/projects or monorepo.
+if os.path.exists(os.path.join(config.test_source_root, 'debuginfo-tests')):
+  if os.path.isfile(
+      os.path.join(config.test_source_root, 'debuginfo-tests', 'lit.cfg.py')):
+    config.excludes.append('debuginfo-tests')
+  else:
+    tools.append(ToolSubst('%test_debuginfo', command=os.path.join(
+      config.llvm_src_root, 'utils', 'test_debuginfo.pl')))
+
 if config.clang_examples:
     tools.append('clang-interpreter')
 
 llvm_config.add_tool_substitutions(tools, tool_dirs)
 
 # Plugins (loadable modules)
 # TODO: This should be supplied by Makefile or autoconf.
 if sys.platform in ['win32', 'cygwin']: