Simplification around ArtifactRepresentation and unique identity (#2771)

* #include an absolute path didn't work - because paths were taken to always be relative.

* WIP in handling artifacts/SourceFiles.

* Add getUniqueIdentity to IPathArtifactRepresentation

* Simplification because around using the representation to provide the uniqueIdentity.

5 files changed, 107 insertions, 61 deletions

diff --git a/source/compiler-core/slang-artifact-representation-impl.cpp b/source/compiler-core/slang-artifact-representation-impl.cpp
index 3fae154bb..105402e6e 100644
--- a/source/compiler-core/slang-artifact-representation-impl.cpp
+++ b/source/compiler-core/slang-artifact-representation-impl.cpp
@@ -67,6 +67,21 @@ bool ExtFileArtifactRepresentation::exists()
     return SLANG_SUCCEEDED(res) && pathType == getPathType();
 }
 
+const char* ExtFileArtifactRepresentation::getUniqueIdentity()
+{
+    if (m_uniqueIdentity.getLength() == 0)
+    {
+        ComPtr<ISlangBlob> uniqueIdentityBlob;
+        if (SLANG_FAILED(m_fileSystem->getFileUniqueIdentity(m_path.getBuffer(), uniqueIdentityBlob.writeRef())))
+        {
+            return nullptr;
+        }
+        m_uniqueIdentity = StringUtil::getString(uniqueIdentityBlob);
+    }
+
+    return m_uniqueIdentity.getLength() ? m_uniqueIdentity.getBuffer() : nullptr;
+}
+
 /* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!! SourceBlobWithPathArtifactRepresentation !!!!!!!!!!!!!!!!!!!!!!!!!!! */
 
 void* SourceBlobWithPathInfoArtifactRepresentation::getInterface(const Guid& guid)
@@ -187,6 +202,23 @@ bool OSFileArtifactRepresentation::exists()
     return SLANG_SUCCEEDED(res) && pathType == SLANG_PATH_TYPE_FILE;
 }
 
+const char* OSFileArtifactRepresentation::getUniqueIdentity()
+{
+    if (m_uniqueIdentity.getLength() == 0)
+    {
+        auto fileSystem = _getFileSystem();
+
+        ComPtr<ISlangBlob> uniqueIdentityBlob;
+        if (SLANG_FAILED(fileSystem->getFileUniqueIdentity(m_path.getBuffer(), uniqueIdentityBlob.writeRef())))
+        {
+            return nullptr;
+        }
+        m_uniqueIdentity = StringUtil::getString(uniqueIdentityBlob);
+    }
+
+    return m_uniqueIdentity.getLength() ? m_uniqueIdentity.getBuffer() : nullptr;
+}
+
 void OSFileArtifactRepresentation::disown()
 {
     if (_isOwned())
diff --git a/source/compiler-core/slang-artifact-representation-impl.h b/source/compiler-core/slang-artifact-representation-impl.h
index 4b6d49e06..5c76b9e7c 100644
--- a/source/compiler-core/slang-artifact-representation-impl.h
+++ b/source/compiler-core/slang-artifact-representation-impl.h
@@ -33,6 +33,7 @@ public:
     // IPathArtifactRepresentation
     virtual SLANG_NO_THROW const char* SLANG_MCALL getPath() SLANG_OVERRIDE { return m_path.getBuffer(); }
     virtual SLANG_NO_THROW SlangPathType SLANG_MCALL getPathType() SLANG_OVERRIDE { return SLANG_PATH_TYPE_FILE; }
+    virtual SLANG_NO_THROW const char* SLANG_MCALL getUniqueIdentity() SLANG_OVERRIDE;
 
     // IOSFileArtifactRepresentation
     virtual SLANG_NO_THROW Kind SLANG_MCALL getKind() SLANG_OVERRIDE { return m_kind; }
@@ -64,6 +65,8 @@ protected:
 
     Kind m_kind;
     String m_path;
+    String m_uniqueIdentity;
+
     ComPtr<IOSFileArtifactRepresentation> m_lockFile;
     ComPtr<ISlangMutableFileSystem> m_fileSystem;
 };
@@ -85,7 +88,8 @@ public:
     // IPathArtifactRepresentation
     virtual SLANG_NO_THROW const char* SLANG_MCALL getPath() SLANG_OVERRIDE { return m_path.getBuffer(); }
     virtual SLANG_NO_THROW SlangPathType SLANG_MCALL getPathType() SLANG_OVERRIDE { return SLANG_PATH_TYPE_FILE; }
-
+    virtual SLANG_NO_THROW const char* SLANG_MCALL getUniqueIdentity() SLANG_OVERRIDE;
+    
     // IExtFileArtifactRepresentation
     virtual SLANG_NO_THROW ISlangFileSystemExt* SLANG_MCALL getFileSystem() SLANG_OVERRIDE { return m_fileSystem; }
 
@@ -104,6 +108,7 @@ protected:
     void* getInterface(const Guid& uuid);
     void* getObject(const Guid& uuid);
 
+    String m_uniqueIdentity;
     String m_path;
     ComPtr<ISlangFileSystemExt> m_fileSystem;
 };
@@ -125,6 +130,7 @@ public:
     // IPathArtifactRepresentation
     virtual SLANG_NO_THROW const char* SLANG_MCALL getPath() SLANG_OVERRIDE { return m_pathInfo.getName().getBuffer(); }
     virtual SLANG_NO_THROW SlangPathType SLANG_MCALL getPathType() SLANG_OVERRIDE { return SLANG_PATH_TYPE_FILE; }
+    virtual SLANG_NO_THROW const char* SLANG_MCALL getUniqueIdentity() SLANG_OVERRIDE { return m_pathInfo.hasUniqueIdentity() ? m_pathInfo.uniqueIdentity.getBuffer() : nullptr; }
 
     SourceBlobWithPathInfoArtifactRepresentation(const PathInfo& pathInfo, ISlangBlob* sourceBlob) :
         m_pathInfo(pathInfo),
diff --git a/source/compiler-core/slang-artifact-representation.h b/source/compiler-core/slang-artifact-representation.h
index a345d762b..3e7659058 100644
--- a/source/compiler-core/slang-artifact-representation.h
+++ b/source/compiler-core/slang-artifact-representation.h
@@ -16,6 +16,9 @@ class IPathArtifactRepresentation : public IArtifactRepresentation
     virtual SLANG_NO_THROW const char* SLANG_MCALL getPath() = 0;
         /// Get type
     virtual SLANG_NO_THROW SlangPathType SLANG_MCALL getPathType() = 0;
+        /// Returns the unique identity. If a unique identity is not supported
+        /// or available will return nullptr.
+    virtual SLANG_NO_THROW const char* SLANG_MCALL getUniqueIdentity() = 0;
 };
 
 /* Represents a path to a file  held on an ISlangFileSystem. */
diff --git a/source/slang/slang-compiler.h b/source/slang/slang-compiler.h
index b49ce4fc3..895834312 100755
--- a/source/slang/slang-compiler.h
+++ b/source/slang/slang-compiler.h
@@ -1495,6 +1495,9 @@ namespace Slang
 
     protected:
         void _addSourceFile(SourceFile* sourceFile);
+        /* Given an artifact, find a PathInfo. 
+        If no PathInfo can be found will return an unknown PathInfo */
+        PathInfo _findSourcePathInfo(IArtifact* artifact);
 
         List<ComPtr<IArtifact>> m_sourceArtifacts;
         // The source file(s) that will be compiled to form this translation unit
diff --git a/source/slang/slang.cpp b/source/slang/slang.cpp
index b831859a5..283e7c16e 100644
--- a/source/slang/slang.cpp
+++ b/source/slang/slang.cpp
@@ -1583,6 +1583,32 @@ void TranslationUnitRequest::addSource(IArtifact* sourceArtifact, SourceFile* so
     _addSourceFile(sourceFile);
 }
 
+PathInfo TranslationUnitRequest::_findSourcePathInfo(IArtifact* artifact)
+{
+    auto pathRep = findRepresentation<IPathArtifactRepresentation>(artifact);
+    
+    if (pathRep && pathRep->getPathType() == SLANG_PATH_TYPE_FILE)
+    {
+        // See if we have a unique identity set with the path
+        if (const auto uniqueIdentity = pathRep->getUniqueIdentity())
+        {
+            return PathInfo::makeNormal(pathRep->getPath(), uniqueIdentity);
+        }
+
+        // If we couldn't get a unique identity, just use the path
+        return PathInfo::makePath(pathRep->getPath());
+    }
+
+    // If there isn't a path, we can try with the name
+    const char* name = artifact->getName();
+    if (name && name[0] != 0)
+    {
+        return PathInfo::makeFromString(name);
+    }
+
+    return PathInfo::makeUnknown();
+}
+
 SlangResult TranslationUnitRequest::requireSourceFiles()
 {
     SLANG_ASSERT(m_sourceFiles.getCount() <= m_sourceArtifacts.getCount());
@@ -1595,84 +1621,60 @@ SlangResult TranslationUnitRequest::requireSourceFiles()
     auto sink = compileRequest->getSink();
     SourceManager* sourceManager = compileRequest->getSourceManager();
 
-    // Get he linkage file system
-    //ISlangFileSystemExt* linkageFileSystem = compileRequest->getLinkage()->getFileSystemExt();
-
     for (Index i = m_sourceFiles.getCount(); i < m_sourceArtifacts.getCount(); ++i)
     {
         IArtifact* artifact = m_sourceArtifacts[i];
 
-        PathInfo pathInfo = PathInfo::makeUnknown();
+        const PathInfo pathInfo = _findSourcePathInfo(artifact);
+        
+        SourceFile* sourceFile = nullptr;
+        ComPtr<ISlangBlob> blob;
 
-        if (auto extRep = findRepresentation<IExtFileArtifactRepresentation>(artifact))
+        // If we have a unique identity see if we have it already
+        if (pathInfo.hasUniqueIdentity())
         {
-            auto extFileSystem = extRep->getFileSystem();
-
-            // TODO(JS):
-            // Ideally we'd confirm that the file system was the same, such we could know that the unique
-            // identity is appropriate for the current file system.
-            //
-            // We just assume compatibility for the moment, because repro will be a different file system
-            // but we need to use the unique identity that is there.
-
-            //if (extFileSystem == linkageFileSystem)
+            // See if this an already loaded source file
+            sourceFile = sourceManager->findSourceFileRecursively(pathInfo.uniqueIdentity);
+            // If we have a sourceFile see if it has a blob
+            if (sourceFile)
             {
-                // Get the unique identity
-                ComPtr<ISlangBlob> uniqueIdentityBlob;
-                if (SLANG_SUCCEEDED(extFileSystem->getFileUniqueIdentity(extRep->getPath(), uniqueIdentityBlob.writeRef())) && uniqueIdentityBlob)
-                {
-                    auto uniqueIdentity = StringUtil::getString(uniqueIdentityBlob);
-
-                    // See if this an already loaded source file
-                    if (auto sourceFile = sourceManager->findSourceFileRecursively(uniqueIdentity))
-                    {
-                        // If the source file has a blob, and the artifact doesn't copy over that representation
-                        if (sourceFile->getContentBlob() && findRepresentation<ISlangBlob>(artifact) == nullptr)
-                        {
-                            artifact->addRepresentationUnknown(sourceFile->getContentBlob());
-                        }
-
-                        _addSourceFile(sourceFile);
-                        continue;
-                    }
-
-                    pathInfo = PathInfo::makeNormal(extRep->getPath(), uniqueIdentity);
-                }
-                else
-                {
-                    pathInfo = PathInfo::makePath(extRep->getPath());
-                }
+                blob = sourceFile->getContentBlob();
             }
         }
 
-        if (pathInfo.type == PathInfo::Type::Unknown)
+        // If we *don't* have a blob try and get a blob from the artifact
+        if (!blob)
         {
-            const auto path = ArtifactUtil::findPath(artifact);
-
-            // If has a path representation we'll make it a FoundPath
-            if (findRepresentation<IPathArtifactRepresentation>(artifact))
-            {
-                pathInfo = PathInfo::makePath(path);
-            }
-            else
+            const SlangResult res = artifact->loadBlob(ArtifactKeep::Yes, blob.writeRef());
+            if (SLANG_FAILED(res))
             {
-                // Otherwise we'll assume it's created from a 'String' even if that's not quite the case
-                pathInfo = PathInfo::makeFromString(path);
+                // Report couldn't load
+                sink->diagnose(SourceLoc(), Diagnostics::cannotOpenFile, pathInfo.getName());
+                return res;
             }
         }
 
-        ComPtr<ISlangBlob> blob;
-        const SlangResult blobRes = artifact->loadBlob(ArtifactKeep::Yes, blob.writeRef());
-        if (SLANG_FAILED(blobRes))
+        // If we don't have a blob on the artifact we can now add the one we have
+        if (!findRepresentation<ISlangBlob>(artifact))
         {
-            // Report couldn't load
-            sink->diagnose(SourceLoc(),
-                Diagnostics::cannotOpenFile,
-                pathInfo.getName());
-            return blobRes;
+            artifact->addRepresentationUnknown(blob);
         }
 
-        auto sourceFile = sourceManager->createSourceFileWithBlob(pathInfo, blob);
+        // If we have a sourceFile check if it has contents, and set the blob if doesn't
+        if (sourceFile)
+        {
+            if (!sourceFile->getContentBlob())
+            {
+                sourceFile->setContents(blob);
+            }
+        }
+        else
+        {
+            // Create a new source file, using the pathInfo and blob
+            sourceFile = sourceManager->createSourceFileWithBlob(pathInfo, blob);
+        }
+  
+        // Finally add the source file
         _addSourceFile(sourceFile);
     }