Fix several silently failing tests (#2767)

* Add missing expected.txt for test

* Diagnostics -> StdWriters in render test

* Allow specifying several test prefixes to run

`slang-test -- tests/foo tests/bar`

* Squash warnings in some tests

* Enable gfx debug layer in gfx test util

Makes this issue present consistently: https://github.com/shader-slang/slang/issues/2766

* Allow DebugDevice to return interfaces instantiated by the debugged object

* Check that we actaully have a shader cache for shader cache tests

---------

Co-authored-by: Yong He <yonghe@outlook.com>

3 files changed, 13 insertions, 19 deletions

diff --git a/tools/slang-test/options.cpp b/tools/slang-test/options.cpp
index 11188d766..ab0d3a01e 100644
--- a/tools/slang-test/options.cpp
+++ b/tools/slang-test/options.cpp
@@ -310,18 +310,7 @@ static bool _isSubCommand(const char* arg)
 
 
     // first positional argument is source shader path
-    if (positionalArgs.getCount())
-    {
-        optionsOut->testPrefix = positionalArgs[0];
-        positionalArgs.removeAt(0);
-    }
-
-    // any remaining arguments represent an error
-    if (positionalArgs.getCount() != 0)
-    {
-        stdError.print("unexpected arguments\n");
-        return SLANG_FAIL;
-    }
+    optionsOut->testPrefixes = std::move(positionalArgs);
 
     if (optionsOut->binDir.getLength() == 0)
     {
diff --git a/tools/slang-test/options.h b/tools/slang-test/options.h
index 26b8e7500..e786a0a74 100644
--- a/tools/slang-test/options.h
+++ b/tools/slang-test/options.h
@@ -52,8 +52,8 @@ struct Options
     // Directory to use when looking for binaries to run. If empty it's not set.
     Slang::String binDir;
 
-    // only run test cases with names that have this prefix. 
-    char const* testPrefix = nullptr;
+    // only run test cases with names have one of these prefixes.
+    Slang::List<const char *> testPrefixes;
 
     // generate extra output (notably: command lines we run)
     bool shouldBeVerbose = false;
diff --git a/tools/slang-test/slang-test-main.cpp b/tools/slang-test/slang-test-main.cpp
index 71f5c04bd..51c618187 100644
--- a/tools/slang-test/slang-test-main.cpp
+++ b/tools/slang-test/slang-test-main.cpp
@@ -3900,15 +3900,20 @@ static bool shouldRunTest(
     if(!endsWithAllowedExtension(context, filePath))
         return false;
 
-    if( context->options.testPrefix )
+    if(!context->options.testPrefixes.getCount())
     {
-        if( strncmp(context->options.testPrefix, filePath.begin(), strlen(context->options.testPrefix)) != 0 )
+        return true;
+    }
+
+    // If we have prefixes, it has to match one of them
+    for(auto& p : context->options.testPrefixes)
+    {
+        if(filePath.startsWith(p))
         {
-            return false;
+            return true;
         }
     }
-
-    return true;
+    return false;
 }
 
 void getFilesInDirectory(String directoryPath, List<String>& files)