SourceMap encoding (#2706)

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

* WIP source map.

* Split out handling of RttiTypeFuncs to a map type.

* Make RttiTypeFuncsMap hold default impls.

* Slightly more sophisticated RttiTypeFuncsMap

* Source map decoding.

* Fix tabs.

* Fix asserts due to negative values.

* Use less obscure mechanisms in SourceMap.

* Source map decoding.
Simplifying SourceMap usage.

1 files changed, 18 insertions, 51 deletions

diff --git a/source/compiler-core/slang-source-map.h b/source/compiler-core/slang-source-map.h
index 0f84878fe..7fd64510a 100644
--- a/source/compiler-core/slang-source-map.h
+++ b/source/compiler-core/slang-source-map.h
@@ -15,73 +15,37 @@
 
 namespace Slang {
 
-/* 
-Support for source maps. Source maps provide a standardized mechanism to associate a location in one output file 
-with another.
-
-* [Source Map Proposal](https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/edit?hl=en_US&pli=1&pli=1)
-* [Chrome Source Map post](https://developer.chrome.com/blog/sourcemaps/)
-* [Base64 VLQs in Source Maps](https://www.lucidchart.com/techblog/2019/08/22/decode-encoding-base64-vlqs-source-maps/)
-
-Example...
-
-{
-"version" : 3,
-"file": "out.js",
-"sourceRoot": "",
-"sources": ["foo.js", "bar.js"],
-"sourcesContent": [null, null],
-"names": ["src", "maps", "are", "fun"],
-"mappings": "A,AAAB;;ABCDE;"
-}
-*/
-
-struct JSONSourceMap
-{
-        /// File version (always the first entry in the object) and must be a positive integer.
-    int32_t version = 3;                    
-        /// An optional name of the generated code that this source map is associated with.
-    String file;                            
-        /// An optional source root, useful for relocating source files on a server or removing repeated values in 
-        /// the “sources” entry.  This value is prepended to the individual entries in the “source” field.
-    String sourceRoot;                        
-        /// A list of original sources used by the “mappings” entry.
-    List<UnownedStringSlice> sources;            
-        /// An optional list of source content, useful when the “source” can’t be hosted. The contents are listed in the same order as the sources in line 5. 
-        /// “null” may be used if some original sources should be retrieved by name.
-        /// Because could be a string or nullptr, we use JSONValue to hold value.
-    List<JSONValue> sourcesContent;    
-        /// A list of symbol names used by the “mappings” entry.
-    List<UnownedStringSlice> names;
-        /// A string with the encoded mapping data.
-    UnownedStringSlice mappings;
-
-    static const StructRttiInfo g_rttiInfo;
-};
-
 struct SourceMap
 {
     struct Entry
     {
         // Note! All column/line are zero indexed
-
-        Index generatedColumn;        ///< The generated column
-        Index sourceFileIndex;        ///< The index into the source name/contents
-        Index sourceLine;            ///< The line number in the originating source
-        Index sourceColumn;            ///< The column number in the originating source
+        Index generatedColumn;          ///< The generated column
+        Index sourceFileIndex;          ///< The index into the source name/contents
+        Index sourceLine;               ///< The line number in the originating source
+        Index sourceColumn;             ///< The column number in the originating source
+        Index nameIndex;                ///< Name index
     };
 
-    SlangResult decode(JSONContainer* container, const JSONSourceMap& src);
+        /// Decode from root into the source map
+    SlangResult decode(JSONContainer* container, JSONValue root, DiagnosticSink* sink);
+
+        /// Converts the source map contents into JSON
+    SlangResult encode(JSONContainer* container, DiagnosticSink* sink, JSONValue& outValue);
 
         /// Get the total number of generated lines
     Count getGeneratedLineCount() const { return m_lineStarts.getCount() - 1; }
         /// Get the entries on the line
     SLANG_FORCE_INLINE ConstArrayView<Entry> getEntriesForLine(Index generatedLine) const;
     
+        /// Clear the contents of the source map
+    void clear();
+
         /// Ctor
     SourceMap():
         m_slicePool(StringSlicePool::Style::Default)
     {
+        clear();
     }
 
     String m_file;
@@ -92,6 +56,9 @@ struct SourceMap
         /// Storage for the contents. Can be unset null to indicate not set. 
     List<StringSlicePool::Handle> m_sourcesContent;
     
+        /// The names
+    List<StringSlicePool::Handle> m_names;
+
     List<Index> m_lineStarts;
     List<Entry> m_lineEntries;
 
@@ -107,7 +74,7 @@ SLANG_FORCE_INLINE ConstArrayView<SourceMap::Entry> SourceMap::getEntriesForLine
     const auto entries = m_lineEntries.begin();
 
     SLANG_ASSERT(start >= 0 && start < m_lineEntries.getCount());
-    SLANG_ASSERT(end >= start && end >= 0 && end < m_lineEntries.getCount());
+    SLANG_ASSERT(end >= start && end >= 0 && end <= m_lineEntries.getCount());
 
     return ConstArrayView<SourceMap::Entry>(entries + start, end - start);
 }