[clang] 87468e8 - compile commands header to source heuristic lower-cases filenames before inferring file types

[Sam McCall via cfe-commits]

Author: Ishaan Gandhi
Date: 2022-04-25T20:40:56+02:00
New Revision: 87468e85fcdcf1bd5055466e34d17436a79017a2

URL: https://github.com/llvm/llvm-project/commit/87468e85fcdcf1bd5055466e34d17436a79017a2
DIFF: https://github.com/llvm/llvm-project/commit/87468e85fcdcf1bd5055466e34d17436a79017a2.diff

LOG: compile commands header to source heuristic lower-cases filenames before inferring file types

This leads to ".C" files being rewritten as ".c" files and being inferred to be "c" files as opposed to "c++" files.

Fixes https://github.com/clangd/clangd/issues/1108

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D124262

Added: 
    

Modified: 
    clang/lib/Tooling/InterpolatingCompilationDatabase.cpp
    clang/unittests/Tooling/CompilationDatabaseTest.cpp

Removed: 
    


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diff  --git a/clang/lib/Tooling/InterpolatingCompilationDatabase.cpp b/clang/lib/Tooling/InterpolatingCompilationDatabase.cpp
index 51e8439b6b79b..0143b5f8df6b6 100644
--- a/clang/lib/Tooling/InterpolatingCompilationDatabase.cpp
+++ b/clang/lib/Tooling/InterpolatingCompilationDatabase.cpp
@@ -328,7 +328,7 @@ class FileIndex {
       StringRef Path = Strings.save(StringRef(OriginalPaths[I]).lower());
 
       Paths.emplace_back(Path, I);
-      Types.push_back(foldType(guessType(Path)));
+      Types.push_back(foldType(guessType(OriginalPaths[I])));
       Stems.emplace_back(sys::path::stem(Path), I);
       auto Dir = ++sys::path::rbegin(Path), DirEnd = sys::path::rend(Path);
       for (int J = 0; J < DirectorySegmentsIndexed && Dir != DirEnd; ++J, ++Dir)

diff  --git a/clang/unittests/Tooling/CompilationDatabaseTest.cpp b/clang/unittests/Tooling/CompilationDatabaseTest.cpp
index adb9de0c1cbaa..8194dd3953c20 100644
--- a/clang/unittests/Tooling/CompilationDatabaseTest.cpp
+++ b/clang/unittests/Tooling/CompilationDatabaseTest.cpp
@@ -836,6 +836,14 @@ TEST_F(InterpolateTest, Case) {
   EXPECT_EQ(getProxy("foo/bar/baz/shout.C"), "FOO/BAR/BAZ/SHOUT.cc");
 }
 
+TEST_F(InterpolateTest, LanguagePreference) {
+  add("foo/bar/baz/exact.C");
+  add("foo/bar/baz/exact.c");
+  add("other/random/path.cpp");
+  // Proxies for ".H" files are ".C" files, and not ".c files".
+  EXPECT_EQ(getProxy("foo/bar/baz/exact.H"), "foo/bar/baz/exact.C");
+}
+
 TEST_F(InterpolateTest, Aliasing) {
   add("foo.cpp", "-faligned-new");