[clang] 8bed59c - [Lex] Fix suggested spelling of /usr/bin/../include/foo

[Sam McCall via cfe-commits]

Author: Sam McCall
Date: 2022-11-25T11:01:22+01:00
New Revision: 8bed59c7e7da2fea41a9167e15c15a8f58a5ede7

URL: https://github.com/llvm/llvm-project/commit/8bed59c7e7da2fea41a9167e15c15a8f58a5ede7
DIFF: https://github.com/llvm/llvm-project/commit/8bed59c7e7da2fea41a9167e15c15a8f58a5ede7.diff

LOG: [Lex] Fix suggested spelling of /usr/bin/../include/foo

Since D60873 we remove dotdots from the search path entries, but not the
filenames we're matching against, so do the latter too.

Since this also removes (single) dots, drop the logic to skip over them.
(Some of this was already dead, some is newly dead).

See D138676 for motivation.

Differential Revision: https://reviews.llvm.org/D138677

Added: 
    

Modified: 
    clang/lib/Lex/HeaderSearch.cpp
    clang/unittests/Lex/HeaderSearchTest.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Lex/HeaderSearch.cpp b/clang/lib/Lex/HeaderSearch.cpp
index e6af122949709..0615002734e94 100644
--- a/clang/lib/Lex/HeaderSearch.cpp
+++ b/clang/lib/Lex/HeaderSearch.cpp
@@ -1928,32 +1928,24 @@ std::string HeaderSearch::suggestPathToFileForDiagnostics(
     llvm::StringRef File, llvm::StringRef WorkingDir, llvm::StringRef MainFile,
     bool *IsSystem) {
   using namespace llvm::sys;
+  
+  llvm::SmallString<32> FilePath = File;
+  path::remove_dots(FilePath, /*remove_dot_dot=*/true);
+  File = FilePath;
 
   unsigned BestPrefixLength = 0;
   // Checks whether `Dir` is a strict path prefix of `File`. If so and that's
   // the longest prefix we've seen so for it, returns true and updates the
   // `BestPrefixLength` accordingly.
-  auto CheckDir = [&](llvm::StringRef Dir) -> bool {
-    llvm::SmallString<32> DirPath(Dir.begin(), Dir.end());
+  auto CheckDir = [&](llvm::SmallString<32> Dir) -> bool {
     if (!WorkingDir.empty() && !path::is_absolute(Dir))
-      fs::make_absolute(WorkingDir, DirPath);
-    path::remove_dots(DirPath, /*remove_dot_dot=*/true);
-    Dir = DirPath;
+      fs::make_absolute(WorkingDir, Dir);
+    path::remove_dots(Dir, /*remove_dot_dot=*/true);
     for (auto NI = path::begin(File), NE = path::end(File),
               DI = path::begin(Dir), DE = path::end(Dir);
-         /*termination condition in loop*/; ++NI, ++DI) {
-      // '.' components in File are ignored.
-      while (NI != NE && *NI == ".")
-        ++NI;
-      if (NI == NE)
-        break;
-
-      // '.' components in Dir are ignored.
-      while (DI != DE && *DI == ".")
-        ++DI;
+         NI != NE; ++NI, ++DI) {
       if (DI == DE) {
-        // Dir is a prefix of File, up to '.' components and choice of path
-        // separators.
+        // Dir is a prefix of File, up to choice of path separators.
         unsigned PrefixLength = NI - path::begin(File);
         if (PrefixLength > BestPrefixLength) {
           BestPrefixLength = PrefixLength;

diff  --git a/clang/unittests/Lex/HeaderSearchTest.cpp b/clang/unittests/Lex/HeaderSearchTest.cpp
index 5024f0d3d6b00..939f5a7210d8a 100644
--- a/clang/unittests/Lex/HeaderSearchTest.cpp
+++ b/clang/unittests/Lex/HeaderSearchTest.cpp
@@ -150,6 +150,14 @@ TEST_F(HeaderSearchTest, DotDotsWithAbsPath) {
             "z");
 }
 
+TEST_F(HeaderSearchTest, BothDotDots) {
+  addSearchDir("/x/../y/");
+  EXPECT_EQ(Search.suggestPathToFileForDiagnostics("/x/../y/z",
+                                                   /*WorkingDir=*/"",
+                                                   /*MainFile=*/""),
+            "z");
+}
+
 TEST_F(HeaderSearchTest, IncludeFromSameDirectory) {
   EXPECT_EQ(Search.suggestPathToFileForDiagnostics("/y/z/t.h",
                                                    /*WorkingDir=*/"",