Path simplification/hash mode, plus bug fixes (#788)

* * Fix memory bug around expanding va_args - needed buffer to have space for terminating 0
* Fix problem with FileWriter defaults being globals, as memory they allocate, will only be freed after return from main - work around by making StdWriters RefObject derived, and kept in scope such the writers are destroyed before checks for leaks is found
* Added SimplifyPathAndHash mode for CacheFileSystem - will simplify the path and see if simplified path is in cache before reading file (limiting amout of underlying file requests)

* * Added calcReplaceChar
* Renamed DefaultFileSystem to OSFileSystem
* Made OSFileSystem convert windows \ to / on linux

* Simplified logic for caching in CacheFileSystem.

* Added pragma-once-c to add extra test, but also so there is an 'include' directory in preprocessor tests.

* Small fixes in pragma once test.

* Simplified cache handling path, so that paths/simplified paths area always added.

* Improve naming of methods for different caches.

2 files changed, 22 insertions, 2 deletions

diff --git a/tools/slang-test/slang-test-main.cpp b/tools/slang-test/slang-test-main.cpp
index 06c2aaf67..d0da4fc61 100644
--- a/tools/slang-test/slang-test-main.cpp
+++ b/tools/slang-test/slang-test-main.cpp
@@ -1818,7 +1818,7 @@ void runTestsInDirectory(
 
 SlangResult innerMain(int argc, char** argv)
 {
-    StdWriters::initDefault();
+    auto stdWriters = StdWriters::initDefaultSingleton();
 
     // The context holds useful things used during testing
     TestContext context;
diff --git a/tools/slang-test/unit-test-path.cpp b/tools/slang-test/unit-test-path.cpp
index e9cfbe2e3..712453e23 100644
--- a/tools/slang-test/unit-test-path.cpp
+++ b/tools/slang-test/unit-test-path.cpp
@@ -35,7 +35,27 @@ static void pathUnitTest()
 
         SLANG_CHECK(Path::Simplify("a:\\what\\..\\.\\..\\is\\.\\..\\this\\.\\") == "a:/../this");
 
+        SLANG_CHECK(Path::Simplify("tests/preprocessor/.\\pragma-once-a.h") == "tests/preprocessor/pragma-once-a.h");
+
+
+        SLANG_CHECK(Path::IsRelative("."));
+        SLANG_CHECK(Path::IsRelative(".."));
+        SLANG_CHECK(Path::IsRelative("blah/.."));
+
+        SLANG_CHECK(Path::IsRelative("blah/.././a"));
+        SLANG_CHECK(Path::IsRelative("a") == false);
+        SLANG_CHECK(Path::IsRelative("blah/a") == false);
+        SLANG_CHECK(Path::IsRelative("a:\\blah/a") == false);
+
+
+        SLANG_CHECK(Path::IsRelative("a:/what/.././../is/./../this/."));
+
+        SLANG_CHECK(Path::IsRelative("a:/what/.././../is/./../this/./"));
+
+        SLANG_CHECK(Path::IsRelative("a:\\what\\..\\.\\..\\is\\.\\..\\this\\.\\"));
+
+
     }
 }
 
-SLANG_UNIT_TEST("Path", pathUnitTest);
\ No newline at end of file
+SLANG_UNIT_TEST("Path", pathUnitTest);