rstudio: clean up and refactor (#357034)

pkgs/applications/editors/rstudio/clang-location.patch

@@ -1,38 +1,23 @@
+diff --git a/src/cpp/core/libclang/LibClang.cpp b/src/cpp/core/libclang/LibClang.cpp
+index f166a43b37..d8024b2ce7 100644
 --- a/src/cpp/core/libclang/LibClang.cpp
 +++ b/src/cpp/core/libclang/LibClang.cpp
-@@ -62,7 +62,7 @@
-
-    // we need to add in the associated libclang headers as
-    // they are not discovered / used by default during compilation
--   FilePath llvmPath = s_libraryPath.getParent().getParent();
-+   FilePath llvmPath("@libclang@");
-    boost::format fmt("%1%/lib/clang/%2%/include");
-    fmt % llvmPath.getAbsolutePath() % version.asString();
-    std::string includePath = fmt.str();
-@@ -74,47 +74,7 @@
-
- std::vector<std::string> systemClangVersions()
- {
--   std::vector<std::string> clangVersions;
--   
--#if defined(__APPLE__)
--   // NOTE: the version of libclang.dylib bundled with Xcode
--   // doesn't seem to work well when loaded as a library
--   // (there seems to be extra orchestration required to get
--   // include paths set up; easier to just depend on command
--   // line tools since we request their installation in other
--   // contexts as well)
--   clangVersions = {
+@@ -84,34 +84,13 @@ std::vector<std::string> systemClangVersions()
+    // line tools since we request their installation in other
+    // contexts as well)
+    clangVersions = {
 -      "/Library/Developer/CommandLineTools/usr/lib/libclang.dylib"
--   };
--#elif defined(__unix__)
--   // default set of versions
--   clangVersions = {
++      "@libclang@/lib/libclang.dylib"
+    };
+ #elif defined(__unix__)
+    // default set of versions
+    clangVersions = {
 -      "/usr/lib/libclang.so",
 -      "/usr/lib/llvm/libclang.so",
 -      "/usr/lib64/libclang.so",
 -      "/usr/lib64/llvm/libclang.so",
--   };
++      "@libclang@/lib/libclang.so",
+    };
 -   
 -   // iterate through the set of available 'llvm' directories
 -   for (const char* prefix : {"/usr/lib", "/usr/lib64"})
@@ -51,11 +36,6 @@
 -         if (path.getFilename().find("llvm") == 0)
 -            clangVersions.push_back(path.completePath("lib/libclang.so.1").getAbsolutePath());
 -   }
--#endif
--   
--   return clangVersions;
-+    return std::vector<std::string> { "@libclang.so@" };
- }
-
-
-
+ #endif
+
+    return clangVersions;