Process tilde in llvm::sys::path::native

Windows does not treat `~` as a reference to home directory, so the call
to `llvm::sys::path::native` on, say, `~/somedir` produces `~\somedir`,
which has different meaning than the original path. With this change
tilde is expanded on Windows to user profile directory. Such behavior
keeps original meaning of the path and is consistent with the algorithm
of `llvm::sys::path::home_directory`.

Differential Revision: https://reviews.llvm.org/D27527

llvm-svn: 296590

2 files changed, 35 insertions, 0 deletions

diff --git a/llvm/lib/Support/Path.cpp b/llvm/lib/Support/Path.cpp
index 4bb035eeccc..0709ec272f5 100644
--- a/llvm/lib/Support/Path.cpp
+++ b/llvm/lib/Support/Path.cpp
@@ -556,8 +556,16 @@ void native(const Twine &path, SmallVectorImpl<char> &result) {
 }
 
 void native(SmallVectorImpl<char> &Path) {
+  if (Path.empty())
+    return;
 #ifdef LLVM_ON_WIN32
   std::replace(Path.begin(), Path.end(), '/', '\\');
+  if (Path[0] == '~' && (Path.size() == 1 || is_separator(Path[1]))) {
+    SmallString<128> PathHome;
+    home_directory(PathHome);
+    PathHome.append(Path.begin() + 1, Path.end());
+    Path = PathHome;
+  }
 #else
   for (auto PI = Path.begin(), PE = Path.end(); PI < PE; ++PI) {
     if (*PI == '\\') {
diff --git a/llvm/unittests/Support/Path.cpp b/llvm/unittests/Support/Path.cpp
index 24f16fd1696..a93f929af78 100644
--- a/llvm/unittests/Support/Path.cpp
+++ b/llvm/unittests/Support/Path.cpp
@@ -968,6 +968,33 @@ TEST(Support, NormalizePath) {
   EXPECT_PATH_IS(Path6, "a\\", "a/");
 
 #undef EXPECT_PATH_IS
+
+#if defined(LLVM_ON_WIN32)
+  SmallString<64> PathHome;
+  path::home_directory(PathHome);
+
+  const char *Path7a = "~/aaa";
+  SmallString<64> Path7(Path7a);
+  path::native(Path7);
+  EXPECT_TRUE(Path7.endswith("\\aaa"));
+  EXPECT_TRUE(Path7.startswith(PathHome));
+  EXPECT_EQ(Path7.size(), PathHome.size() + strlen(Path7a + 1));
+
+  const char *Path8a = "~";
+  SmallString<64> Path8(Path8a);
+  path::native(Path8);
+  EXPECT_EQ(Path8, PathHome);
+
+  const char *Path9a = "~aaa";
+  SmallString<64> Path9(Path9a);
+  path::native(Path9);
+  EXPECT_EQ(Path9, "~aaa");
+
+  const char *Path10a = "aaa/~/b";
+  SmallString<64> Path10(Path10a);
+  path::native(Path10);
+  EXPECT_EQ(Path10, "aaa\\~\\b");
+#endif
 }
 
 TEST(Support, RemoveLeadingDotSlash) {