Remove some SVN-specific code.

[thakis]

Summary

$URL$ is an SVN keyword substitution enabled via
svn propset svn:keywords "URL" tools/clang/lib/Basic/Version.cpp.
Now that we no longer use SVN, it's no longer being replaced by
anything, and we no longer offer svn exports. So remove the
$URL$-specific logic.

The "cfe" path prefix removal also no longer makes sense now that
we're on git: Both CLANG_REPOSITORY and LLVM_REPOSITORY are usually
set to https://github.com/llvm/llvm-project.git

So remove that too, and remove the "llvm" prefix removal for symmetry.
With the github url, "llvm" _is_ found in the string, but not in
the place the function expected. Nobody noticed since the llvm
repository path is only used if CLANG_REVISION and LLVM_REVISION are
different, which in the git monorepo world they never should be.
(I might remove the "// Support LLVM in a separate repository"
block in a separate commit.)

[Eugene.Zelenko]

clang/lib/Basic/Version.cpp

33

return {} should be better.

42

return {} should be better.

50

return {} should be better.

[hans]

clang/lib/Basic/Version.cpp

33

Why? I think "" is clearer for a string.

[Eugene.Zelenko]

clang/lib/Basic/Version.cpp

33

It's default non-trivial object initialization. Also not need for implicit cast.

[hans]

clang/lib/Basic/Version.cpp

33

I still think

return "";

is a much clearer way of returning an empty string.

clang/lib/Basic/Version.cpp

 
 namespace clang {
 
 std::string getClangRepositoryPath() {
 #if defined(CLANG_REPOSITORY_STRING)
   return CLANG_REPOSITORY_STRING;
 #else
 #ifdef CLANG_REPOSITORY
-  StringRef URL(CLANG_REPOSITORY);
+  return CLANG_REPOSITORY;
 #else
-  StringRef URL("");
+  return "";
 #endif
-
-  // If the CLANG_REPOSITORY is empty, try to use the SVN keyword. This helps us
-  // pick up a tag in an SVN export, for example.
-  StringRef SVNRepository("$URL$");
-  if (URL.empty()) {
-    URL = SVNRepository.slice(SVNRepository.find(':'),
-                              SVNRepository.find("/lib/Basic"));
-  }
-
-  // Strip off version from a build from an integration branch.
-  URL = URL.slice(0, URL.find("/src/tools/clang"));
-
-  // Trim path prefix off, assuming path came from standard cfe path.
-  size_t Start = URL.find("cfe/");
-  if (Start != StringRef::npos)
-    URL = URL.substr(Start + 4);
-
-  return URL;
 #endif
 }
 
 std::string getLLVMRepositoryPath() {
 #ifdef LLVM_REPOSITORY
-  StringRef URL(LLVM_REPOSITORY);
+  return LLVM_REPOSITORY;
 #else
-  StringRef URL("");
+  return "";
 #endif
-
-  // Trim path prefix off, assuming path came from standard llvm path.
-  // Leave "llvm/" prefix to distinguish the following llvm revision from the
-  // clang revision.
-  size_t Start = URL.find("llvm/");
-  if (Start != StringRef::npos)
-    URL = URL.substr(Start);
-
-  return URL;
 }
 
 std::string getClangRevision() {
 #ifdef CLANG_REVISION
   return CLANG_REVISION;
 #else
   return "";
 #endif
 }
 
 std::string getLLVMRevision() {
 #ifdef LLVM_REVISION
   return LLVM_REVISION;
 #else
   return "";