Fix Go generic symbol extraction

changelog.d/unreleased/2047.fixed.md

@@ -0,0 +1,17 @@
+---
+category: fixed
+issues:
+  - 2047
+affected:
+  - src/CodeIndex/Indexer/Symbols/SymbolExtractor.cs
+  - src/CodeIndex/Indexer/Symbols/SymbolExtractor.Go.cs
+  - tests/CodeIndex.Tests/SymbolExtractorTests.cs
+---
+
+## English
+
+- **Go embedded generic struct types are indexed (#2047)** — struct bodies now expose embedded generic types such as `Reader[T]` and `*pkg.Writer[U]` as import-kind symbols without treating ordinary named fields as embedded types.
+
+## 日本語
+
+- **Go struct の embedded generic type を index するようになりました (#2047)** — struct body 内の `Reader[T]` や `*pkg.Writer[U]` などを import-kind symbol として公開し、通常の named field は embedded type として扱いません。

changelog.d/unreleased/2048.fixed.md

@@ -0,0 +1,16 @@
+---
+category: fixed
+issues:
+  - 2048
+affected:
+  - src/CodeIndex/Indexer/Symbols/SymbolExtractor.Go.cs
+  - tests/CodeIndex.Tests/SymbolExtractorTests.cs
+---
+
+## English
+
+- **Go blank identifiers are no longer indexed as properties (#2048)** — `var` and `const` declarations skip `_` while preserving ordinary names such as `_unused`.
+
+## 日本語
+
+- **Go の blank identifier を property として index しなくなりました (#2048)** — `var` / `const` 宣言では `_` を除外しつつ、`_unused` のような通常の名前は維持します。

changelog.d/unreleased/2049.fixed.md

@@ -0,0 +1,17 @@
+---
+category: fixed
+issues:
+  - 2049
+affected:
+  - src/CodeIndex/Indexer/Symbols/SymbolExtractor.cs
+  - src/CodeIndex/Indexer/Symbols/SymbolExtractor.Go.cs
+  - tests/CodeIndex.Tests/SymbolExtractorTests.cs
+---
+
+## English
+
+- **Go interface method signatures preserve type parameters (#2049)** — interface method extraction now recognizes bracketed method type parameters and stores the candidate method signature instead of the surrounding raw line.
+
+## 日本語
+
+- **Go interface method の signature が type parameter を保持するようになりました (#2049)** — interface method 抽出は bracket 付き method type parameter を認識し、周囲の raw line ではなく候補 method signature を保存します。

changelog.d/unreleased/2050.fixed.md

@@ -0,0 +1,16 @@
+---
+category: fixed
+issues:
+  - 2050
+affected:
+  - src/CodeIndex/Indexer/Symbols/SymbolExtractor.Go.cs
+  - tests/CodeIndex.Tests/SymbolExtractorTests.cs
+---
+
+## English
+
+- **Go build directives and CGO imports are exposed as metadata (#2050)** — `//go:build` / `//go:test` comments are indexed as annotation symbols, and `import "C"` is classified as `cgo` instead of a regular import.
+
+## 日本語
+
+- **Go の build directive と CGO import を metadata として公開するようになりました (#2050)** — `//go:build` / `//go:test` comment は annotation symbol として index され、`import "C"` は通常 import ではなく `cgo` として分類されます。

src/CodeIndex/Indexer/Symbols/SymbolExtractor.Go.cs

@@ -16,6 +16,9 @@ private static bool TryHandleGoBlockLine(
     {
         var trimmed = line.TrimStart();
 
+        if (TryAddGoDirectiveSymbol(fileId, line, lineIndex, symbols, trimmed))
+            return true;
+
         if (inImportBlock)
         {
             if (trimmed.Length == 0
@@ -83,7 +86,8 @@ private static bool TryAddGoTypeSymbol(
         int lineIndex,
         List<SymbolRecord> symbols,
         string typeText,
-        ref int goTypeBodyDepth)
+        ref int goTypeBodyDepth,
+        ref string? goTypeBodyKind)
     {
         var normalizedTypeText = typeText.StartsWith("type", StringComparison.Ordinal)
             ? typeText["type".Length..].TrimStart()
@@ -99,7 +103,12 @@ private static bool TryAddGoTypeSymbol(
                 ? "protocol"
                 : "class";
         if (HasGoSymbol(symbols, fileId, lineIndex + 1, kind, name))
+        {
+            if (kind == "struct")
+                TryAddGoStructEmbeddedTypeSymbols(fileId, rawLine, lineIndex, symbols, ExtractGoInlineTypeBody(typeText));
+
             return true;
+        }
         var startColumn = rawLine.IndexOf(name, StringComparison.Ordinal);
         if (startColumn < 0)
             startColumn = rawLine.Length - rawLine.TrimStart().Length;
@@ -121,8 +130,17 @@ private static bool TryAddGoTypeSymbol(
             },
             rawLine);
 
-        if (kind is "struct" or "protocol")
+        if (kind == "struct")
+        {
+            TryAddGoStructEmbeddedTypeSymbols(fileId, rawLine, lineIndex, symbols, ExtractGoInlineTypeBody(typeText));
             goTypeBodyDepth = CountGoBraceDelta(typeText);
+            goTypeBodyKind = goTypeBodyDepth > 0 ? kind : null;
+        }
+        else if (kind == "protocol")
+        {
+            goTypeBodyDepth = CountGoBraceDelta(typeText);
+            goTypeBodyKind = goTypeBodyDepth > 0 ? kind : null;
+        }
 
         return true;
     }
@@ -140,6 +158,9 @@ private static bool TryAddGoValueSymbol(
 
         foreach (var name in match.Groups["names"].Value.Split(',', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))
         {
+            if (name == "_")
+                continue;
+
             if (HasGoSymbol(symbols, fileId, lineIndex + 1, "property", name))
                 continue;
 
@@ -349,6 +370,7 @@ private static bool TryAddGoImportSymbol(
             return true;
 
         var name = match.Groups["name"].Value.Trim();
+        var kind = string.Equals(name, @"""C""", StringComparison.Ordinal) ? "cgo" : "import";
         var startColumn = rawLine.IndexOf(name, StringComparison.Ordinal);
         if (startColumn < 0)
             startColumn = rawLine.IndexOf(importText, StringComparison.Ordinal);
@@ -362,7 +384,7 @@ private static bool TryAddGoImportSymbol(
             new SymbolRecord
             {
                 FileId = fileId,
-                Kind = "import",
+                Kind = kind,
                 Name = name,
                 Line = lineIndex + 1,
                 StartLine = lineIndex + 1,
@@ -374,6 +396,46 @@ private static bool TryAddGoImportSymbol(
         return true;
     }
 
+    private static bool TryAddGoDirectiveSymbol(
+        long fileId,
+        string rawLine,
+        int lineIndex,
+        List<SymbolRecord> symbols,
+        string trimmed)
+    {
+        if (!trimmed.StartsWith("//go:build", StringComparison.Ordinal)
+            && !trimmed.StartsWith("//go:test", StringComparison.Ordinal))
+        {
+            return false;
+        }
+
+        var name = trimmed[2..].Trim();
+        if (HasGoSymbol(symbols, fileId, lineIndex + 1, "annotation", name))
+            return true;
+
+        var startColumn = rawLine.IndexOf("//go:", StringComparison.Ordinal);
+        if (startColumn < 0)
+            startColumn = rawLine.Length - rawLine.TrimStart().Length;
+
+        AddSymbolRecord(
+            symbols,
+            cssSeenSymbols: null,
+            lineIndex + 1,
+            new SymbolRecord
+            {
+                FileId = fileId,
+                Kind = "annotation",
+                Name = name,
+                Line = lineIndex + 1,
+                StartLine = lineIndex + 1,
+                StartColumn = startColumn,
+                EndLine = lineIndex + 1,
+                Signature = trimmed,
+            },
+            rawLine);
+        return true;
+    }
+
     private static void ExtractGoInterfaceMethods(long fileId, string[] lines, List<SymbolRecord> symbols)
     {
         var awaitingInterfaceBody = false;
@@ -527,7 +589,7 @@ private static bool TryAddGoInterfaceMethodSymbol(
                 StartLine = lineIndex + 1,
                 StartColumn = startColumn,
                 EndLine = lineIndex + 1,
-                Signature = rawLine.Trim(),
+                Signature = candidate.Trim(),
             },
             rawLine);
         return true;
@@ -579,6 +641,91 @@ private static bool TryAddGoInterfaceEmbeddedTypeSymbol(
         return true;
     }
 
+    private static string ExtractGoInlineTypeBody(string typeText)
+    {
+        var openBraceIndex = typeText.IndexOf('{');
+        if (openBraceIndex < 0)
+            return string.Empty;
+
+        var body = typeText[(openBraceIndex + 1)..];
+        var closeBraceIndex = body.LastIndexOf('}');
+        return closeBraceIndex >= 0 ? body[..closeBraceIndex] : body;
+    }
+
+    private static void TryAddGoStructEmbeddedTypeSymbols(
+        long fileId,
+        string rawLine,
+        int lineIndex,
+        List<SymbolRecord> symbols,
+        string bodyText)
+    {
+        if (string.IsNullOrWhiteSpace(bodyText))
+            return;
+
+        foreach (var segment in bodyText.Split(';', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))
+        {
+            var candidate = segment;
+            var trailingBraceIndex = candidate.IndexOf('}');
+            if (trailingBraceIndex >= 0)
+                candidate = candidate[..trailingBraceIndex].TrimEnd();
+
+            var lineCommentIndex = candidate.IndexOf("//", StringComparison.Ordinal);
+            if (lineCommentIndex >= 0)
+                candidate = candidate[..lineCommentIndex].TrimEnd();
+
+            var blockCommentIndex = candidate.IndexOf("/*", StringComparison.Ordinal);
+            if (blockCommentIndex >= 0)
+                candidate = candidate[..blockCommentIndex].TrimEnd();
+
+            var tagIndex = candidate.IndexOf('`');
+            if (tagIndex >= 0)
+                candidate = candidate[..tagIndex].TrimEnd();
+
+            if (candidate.Length == 0)
+                continue;
+
+            TryAddGoStructEmbeddedTypeSymbol(fileId, rawLine, lineIndex, symbols, candidate);
+        }
+    }
+
+    private static bool TryAddGoStructEmbeddedTypeSymbol(
+        long fileId,
+        string rawLine,
+        int lineIndex,
+        List<SymbolRecord> symbols,
+        string candidate)
+    {
+        var match = GoStructEmbeddedTypeRegex.Match(candidate);
+        if (!match.Success)
+            return false;
+
+        var name = match.Groups["name"].Value.Trim();
+        if (name.Length == 0 || HasGoSymbol(symbols, fileId, lineIndex + 1, "import", name))
+            return true;
+
+        var startColumn = rawLine.IndexOf(name, StringComparison.Ordinal);
+        if (startColumn < 0)
+            startColumn = rawLine.Length - rawLine.TrimStart().Length;
+
+        AddSymbolRecord(
+            symbols,
+            cssSeenSymbols: null,
+            lineIndex + 1,
+            new SymbolRecord
+            {
+                FileId = fileId,
+                Kind = "import",
+                Name = name,
+                Line = lineIndex + 1,
+                StartLine = lineIndex + 1,
+                StartColumn = startColumn,
+                EndLine = lineIndex + 1,
+                Signature = candidate.Trim(),
+            },
+            rawLine);
+        return true;
+    }
+
     private static bool HasGoSymbol(List<SymbolRecord> symbols, long fileId, int lineNumber, string kind, string name)
     {
         return symbols.Any(symbol =>
@@ -820,6 +967,7 @@ private static void ExtractGoGroupedDeclarations(long fileId, string[] lines, Li
         string? blockKind = null;
         ExtractGoInterfaceMethods(fileId, lines, symbols);
         var typeBodyDepth = 0;
+        string? typeBodyKind = null;
         var goBlockDepth = 0;
         var goBlockInBlockComment = false;
         var goBlockInRawString = false;
@@ -831,9 +979,14 @@ private static void ExtractGoGroupedDeclarations(long fileId, string[] lines, Li
 
             if (typeBodyDepth > 0)
             {
+                if (typeBodyKind == "struct")
+                    TryAddGoStructEmbeddedTypeSymbols(fileId, line, i, symbols, trimmed);
+
                 typeBodyDepth += CountGoBraceDelta(line);
                 if (typeBodyDepth < 0)
                     typeBodyDepth = 0;
+                if (typeBodyDepth == 0)
+                    typeBodyKind = null;
                 continue;
             }
 
@@ -849,13 +1002,15 @@ private static void ExtractGoGroupedDeclarations(long fileId, string[] lines, Li
                 || trimmed.StartsWith("//", StringComparison.Ordinal)
                 || trimmed.StartsWith("/*", StringComparison.Ordinal))
             {
+                TryAddGoDirectiveSymbol(fileId, line, i, symbols, trimmed);
                 continue;
             }
 
             if (trimmed.StartsWith(")", StringComparison.Ordinal))
             {
                 blockKind = null;
                 typeBodyDepth = 0;
+                typeBodyKind = null;
                 continue;
             }
 
@@ -864,7 +1019,7 @@ private static void ExtractGoGroupedDeclarations(long fileId, string[] lines, Li
                 switch (blockKind)
                 {
                     case "type":
-                        TryAddGoTypeSymbol(fileId, line, i, symbols, trimmed, ref typeBodyDepth);
+                        TryAddGoTypeSymbol(fileId, line, i, symbols, trimmed, ref typeBodyDepth, ref typeBodyKind);
                         break;
                     case "const":
                     case "var":
@@ -910,7 +1065,7 @@ private static void ExtractGoGroupedDeclarations(long fileId, string[] lines, Li
 
             if (trimmed.StartsWith("type", StringComparison.Ordinal))
             {
-                TryAddGoTypeSymbol(fileId, line, i, symbols, trimmed, ref typeBodyDepth);
+                TryAddGoTypeSymbol(fileId, line, i, symbols, trimmed, ref typeBodyDepth, ref typeBodyKind);
                 continue;
             }
 

src/CodeIndex/Indexer/Symbols/SymbolExtractor.cs

@@ -219,11 +219,14 @@ public static int GetContractVersion(string? lang)
         @"^\s*(?:type\s+)?\w+(?:\[[^\]]+\])?\s+interface\b",
         RegexOptions.Compiled | RegexOptions.CultureInvariant);
     private static readonly Regex GoInterfaceMethodRegex = new(
-        @"^\s*(?<name>[A-Za-z_]\w*)\s*\(",
+        @"^\s*(?<name>[A-Za-z_]\w*)\s*(?:\[[^\]\r\n]+\])?\s*\(",
         RegexOptions.Compiled | RegexOptions.CultureInvariant);
     private static readonly Regex GoInterfaceEmbeddedTypeRegex = new(
         @"^\s*(?:~\s*)?(?<name>[A-Za-z_]\w*(?:\s*\.\s*[A-Za-z_]\w*)*)(?:\[[^\]\r\n]+\])?\s*$",
         RegexOptions.Compiled | RegexOptions.CultureInvariant);
+    private static readonly Regex GoStructEmbeddedTypeRegex = new(
+        @"^\s*\*?\s*(?<name>[A-Za-z_]\w*(?:\s*\.\s*[A-Za-z_]\w*)*)(?:\[[^\]\r\n]+\])?\s*$",
+        RegexOptions.Compiled | RegexOptions.CultureInvariant);
     private static readonly HashSet<string> GoInterfaceEmbeddedTypeBlacklist = new(StringComparer.Ordinal)
     {
         "bool",