[clangd] Adjust compile commands to be applicable for tooling

Summary:
As can be seen in https://github.com/llvm-mirror/clang/blob/master/lib/Tooling/Tooling.cpp#L385
clang tool invocations adjust commands normally like this. In clangd we have
different code paths for invoking a frontend action(preamble builds, ast builds,
background index, clangd-indexer) they all work on the same GlobalCompilationDatabase
abstraction, but later on are subject to different modifications.

This patch makes sure all of the clangd actions make use of the same compile
commands before invocation.

Enables background-index to work on chromium codebase(since they had dependency
file output in their compile commands).

Reviewers: gribozavr, hokein

Subscribers: ilya-biryukov, ioeric, MaskRay, jkorous, arphaman, jdoerfert, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D59086

llvm-svn: 355669

clang-tools-extra/clangd/GlobalCompilationDatabase.cpp

@@ -21,11 +21,17 @@ namespace {
 
 void adjustArguments(tooling::CompileCommand &Cmd,
                      llvm::StringRef ResourceDir) {
+  tooling::ArgumentsAdjuster ArgsAdjuster = tooling::combineAdjusters(
+      // clangd should not write files to disk, including dependency files
+      // requested on the command line.
+      tooling::getClangStripDependencyFileAdjuster(),
       // Strip plugin related command line arguments. Clangd does
       // not support plugins currently. Therefore it breaks if
       // compiler tries to load plugins.
-  Cmd.CommandLine =
+      tooling::combineAdjusters(tooling::getStripPluginsAdjuster(),
-      tooling::getStripPluginsAdjuster()(Cmd.CommandLine, Cmd.Filename);
+                                tooling::getClangSyntaxOnlyAdjuster()));
+
+  Cmd.CommandLine = ArgsAdjuster(Cmd.CommandLine, Cmd.Filename);
   // Inject the resource dir.
   // FIXME: Don't overwrite it if it's already there.
   if (!ResourceDir.empty())

clang-tools-extra/unittests/clangd/GlobalCompilationDatabaseTests.cpp

@@ -16,15 +16,18 @@
 namespace clang {
 namespace clangd {
 namespace {
+using ::testing::AllOf;
+using ::testing::Contains;
 using ::testing::ElementsAre;
 using ::testing::EndsWith;
+using ::testing::Not;
 
 TEST(GlobalCompilationDatabaseTest, FallbackCommand) {
   DirectoryBasedGlobalCompilationDatabase DB(None);
   auto Cmd = DB.getFallbackCommand(testPath("foo/bar.cc"));
   EXPECT_EQ(Cmd.Directory, testPath("foo"));
-  EXPECT_THAT(Cmd.CommandLine, ElementsAre(
+  EXPECT_THAT(Cmd.CommandLine,
-    EndsWith("clang"), testPath("foo/bar.cc")));
+              ElementsAre(EndsWith("clang"), testPath("foo/bar.cc")));
   EXPECT_EQ(Cmd.Output, "");
 
   // .h files have unknown language, so they are parsed liberally as obj-c++.
@@ -65,16 +68,18 @@ protected:
 
 TEST_F(OverlayCDBTest, GetCompileCommand) {
   OverlayCDB CDB(Base.get(), {}, std::string(""));
-  EXPECT_EQ(CDB.getCompileCommand(testPath("foo.cc")),
+  EXPECT_THAT(CDB.getCompileCommand(testPath("foo.cc"))->CommandLine,
-            Base->getCompileCommand(testPath("foo.cc")));
+              AllOf(Contains(testPath("foo.cc")), Contains("-DA=1")));
   EXPECT_EQ(CDB.getCompileCommand(testPath("missing.cc")), llvm::None);
 
   auto Override = cmd(testPath("foo.cc"), "-DA=3");
   CDB.setCompileCommand(testPath("foo.cc"), Override);
-  EXPECT_EQ(CDB.getCompileCommand(testPath("foo.cc")), Override);
+  EXPECT_THAT(CDB.getCompileCommand(testPath("foo.cc"))->CommandLine,
+              Contains("-DA=3"));
   EXPECT_EQ(CDB.getCompileCommand(testPath("missing.cc")), llvm::None);
   CDB.setCompileCommand(testPath("missing.cc"), Override);
-  EXPECT_EQ(CDB.getCompileCommand(testPath("missing.cc")), Override);
+  EXPECT_THAT(CDB.getCompileCommand(testPath("missing.cc"))->CommandLine,
+              Contains("-DA=3"));
 }
 
 TEST_F(OverlayCDBTest, GetFallbackCommand) {
@@ -88,7 +93,8 @@ TEST_F(OverlayCDBTest, NoBase) {
   EXPECT_EQ(CDB.getCompileCommand(testPath("bar.cc")), None);
   auto Override = cmd(testPath("bar.cc"), "-DA=5");
   CDB.setCompileCommand(testPath("bar.cc"), Override);
-  EXPECT_EQ(CDB.getCompileCommand(testPath("bar.cc")), Override);
+  EXPECT_THAT(CDB.getCompileCommand(testPath("bar.cc"))->CommandLine,
+              Contains("-DA=5"));
 
   EXPECT_THAT(CDB.getFallbackCommand(testPath("foo.cc")).CommandLine,
               ElementsAre(EndsWith("clang"), testPath("foo.cc"), "-DA=6"));
@@ -111,6 +117,35 @@ TEST_F(OverlayCDBTest, Watch) {
                                    ElementsAre("A.cpp"), ElementsAre("C.cpp")));
 }
 
+TEST_F(OverlayCDBTest, Adjustments) {
+  OverlayCDB CDB(Base.get(), {}, std::string(""));
+  auto Cmd = CDB.getCompileCommand(testPath("foo.cc")).getValue();
+  // Delete the file name.
+  Cmd.CommandLine.pop_back();
+
+  // Check dependency file commands are dropped.
+  Cmd.CommandLine.push_back("-MF");
+  Cmd.CommandLine.push_back("random-dependency");
+
+  // Check plugin-related commands are dropped.
+  Cmd.CommandLine.push_back("-Xclang");
+  Cmd.CommandLine.push_back("-load");
+  Cmd.CommandLine.push_back("-Xclang");
+  Cmd.CommandLine.push_back("random-plugin");
+
+  Cmd.CommandLine.push_back("-DA=5");
+  Cmd.CommandLine.push_back(Cmd.Filename);
+
+  CDB.setCompileCommand(testPath("foo.cc"), Cmd);
+
+  EXPECT_THAT(CDB.getCompileCommand(testPath("foo.cc"))->CommandLine,
+              AllOf(Contains("-fsyntax-only"), Contains("-DA=5"),
+                    Contains(testPath("foo.cc")), Not(Contains("-MF")),
+                    Not(Contains("random-dependency")),
+                    Not(Contains("-Xclang")), Not(Contains("-load")),
+                    Not(Contains("random-plugin"))));
+}
+
 } // namespace
 } // namespace clangd
 } // namespace clang