[clangd] Disable predefined macros in tests. NFC

These aren't needed. With them the generated predefines buffer is 13KB.
For every TestTU, we must:
 - generate the buffer (3 times: parsing preamble, scanning preamble, main file)
 - parse the buffer (again 3 times)
 - serialize all the macros it defines in the PCH
 - compress the buffer itself to write it into the PCH
 - decompress it from the PCH

Avoiding this reduces unit test time by ~25%.

Differential Revision: https://reviews.llvm.org/D125172

diff --git a/clang-tools-extra/clangd/unittests/IncludeCleanerTests.cpp b/clang-tools-extra/clangd/unittests/IncludeCleanerTests.cpp
index 77d4e28..c4e9095 100644 (file)
--- a/clang-tools-extra/clangd/unittests/IncludeCleanerTests.cpp
+++ b/clang-tools-extra/clangd/unittests/IncludeCleanerTests.cpp
@@ -386,9 +386,9 @@ TEST(IncludeCleaner, VirtualBuffers) {
 
     using flags::FLAGS_FOO;
 
-    // CLI will come from a define, __llvm__ is a built-in. In both cases, they
+    // CLI will come from a define, __cplusplus is a built-in. In both cases, they
     // come from non-existent files.
-    int y = CLI + __llvm__;
+    int y = CLI + __cplusplus;
 
     int concat(a, b) = 42;
     )cpp";

diff --git a/clang-tools-extra/clangd/unittests/TestTU.cpp b/clang-tools-extra/clangd/unittests/TestTU.cpp
index 1de663a..78a8406 100644 (file)
--- a/clang-tools-extra/clangd/unittests/TestTU.cpp
+++ b/clang-tools-extra/clangd/unittests/TestTU.cpp
@@ -40,7 +40,9 @@ ParseInputs TestTU::inputs(MockFS &FS) const {
   ParseInputs Inputs;
   Inputs.FeatureModules = FeatureModules;
   auto &Argv = Inputs.CompileCommand.CommandLine;
-  Argv = {"clang"};
+  // In tests, omit predefined macros (__GNUC__ etc) for a 25% speedup.
+  // There are hundreds, and we'd generate, parse, serialize, and re-parse them!
+  Argv = {"clang", "-Xclang", "-undef"};
   // FIXME: this shouldn't need to be conditional, but it breaks a
   // GoToDefinition test for some reason (getMacroArgExpandedLocation fails).
   if (!HeaderCode.empty()) {