[llvm] [CASPlugin] Move CASPluginTest next to the CAS unit tests (PR #227546)

[Nico Weber via llvm-commits]

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@@ -33,22 +32,9 @@ using namespace llvm::unittest::cas;
 // fixed.
 #if !LLVM_HWADDRESS_SANITIZER_BUILD
 
-extern const char *TestMainArgv0;
-static std::string TestStringArg1("castest-string-arg1");
-
-/// \returns the path of the libCASPluginTest dynamic library, which implements
+/// \returns the path of the CASPluginTest dynamic library, which implements
 /// the CAS plugin API for testing purposes.
-static std::string getCASPluginPath() {
-  std::string Executable =
-      sys::fs::getMainExecutable(TestMainArgv0, &TestStringArg1);
-  llvm::SmallString<256> PathBuf(sys::path::parent_path(Executable));
-#if !defined(_WIN32) || defined(__MINGW32__)
-  sys::path::append(PathBuf, "libCASPluginTest" LLVM_PLUGIN_EXT);
-#else
-  sys::path::append(PathBuf, "CASPluginTest" LLVM_PLUGIN_EXT);
-#endif
-  return std::string(PathBuf);
-}
+static std::string getCASPluginPath() { return CAS_PLUGIN_PATH; }
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nico wrote:

(note to future self: llvm/unittests/Analysis/PluginInlineOrderAnalysisTest.cpp has a different take on this)

https://github.com/llvm/llvm-project/pull/227546