Fix C# graph and LSP common-token conflation

changelog.d/unreleased/2818.fixed.md

@@ -0,0 +1,18 @@
+---
+category: fixed
+issues:
+  - 2818
+affected:
+  - src/CodeIndex/Database/DbReader.GraphQueries.cs
+  - src/CodeIndex/Indexer/Symbols/SymbolExtractor.CSharpScanner.cs
+  - tests/CodeIndex.Tests/DbReaderTests.cs
+  - tests/CodeIndex.Tests/SymbolExtractorTests.cs
+---
+
+## English
+
+- **C# graph queries no longer conflate common member calls across receivers (#2818)** - member calls such as `paths.ToList()` and `Guid.NewGuid()` inside argument expressions are no longer indexed as standalone function definitions, and bare C# caller queries skip receiver-qualified calls such as `reader.GetString()`.
+
+## 日本語
+
+- **C# graph query が receiver の異なる common member call を混同しないようになりました (#2818)** - 引数式の中にある `paths.ToList()` や `Guid.NewGuid()` のような member call を独立した function definition として index せず、裸の C# caller query では `reader.GetString()` のような receiver-qualified call を除外します。

changelog.d/unreleased/2831.fixed.md

@@ -0,0 +1,16 @@
+---
+category: fixed
+issues:
+  - 2831
+affected:
+  - src/CodeIndex/Lsp/LspServer.cs
+  - tests/CodeIndex.Tests/LspServerTests.cs
+---
+
+## English
+
+- **LSP definition and references now prefer the current indexed document for common tokens (#2831)** - `textDocument/definition` and `textDocument/references` use the resolved document path before falling back to workspace-wide exact matches, avoiding unrelated same-named symbols in other files.
+
+## 日本語
+
+- **LSP definition / references が common token で現在の indexed document を優先するようになりました (#2831)** - `textDocument/definition` と `textDocument/references` は workspace 全体の exact match に fallback する前に解決済み document path を使うため、別ファイルの同名 symbol を混ぜにくくなりました。

src/CodeIndex/Database/DbReader.GraphQueries.cs

@@ -7,6 +7,43 @@ namespace CodeIndex.Database;
 
 public partial class DbReader
 {
+    private static readonly HashSet<string> CSharpReceiverQualifiedBareMemberFilterNames = new(StringComparer.Ordinal)
+    {
+        "GetString",
+        "ToList",
+        "NewGuid",
+    };
+
+    private static string BuildCSharpBareMemberGraphReferenceFilter(
+        string query,
+        string? lang,
+        bool exact,
+        string contextSql,
+        string fileAlias,
+        string referenceAlias)
+    {
+        if (!ShouldFilterCSharpReceiverQualifiedBareMemberQuery(query, lang, exact))
+            return string.Empty;
+
+        return $" AND NOT ({fileAlias}.lang = 'csharp' AND {referenceAlias}.reference_kind = 'call' AND (instr({contextSql}, '.' || {referenceAlias}.symbol_name || '(') > 0 OR instr({contextSql}, '.' || {referenceAlias}.symbol_name || '<') > 0 OR ({referenceAlias}.column_number > 1 AND substr({contextSql}, {referenceAlias}.column_number - 1, 1) = '.' AND substr(ltrim(substr({contextSql}, {referenceAlias}.column_number + length({referenceAlias}.symbol_name))), 1, 1) IN ('(', '<'))))";
+    }
+
+    private static bool ShouldFilterCSharpReceiverQualifiedBareMemberQuery(string query, string? lang, bool exact)
+    {
+        if (!exact || lang is not null and not "csharp" || SqlNameResolver.HasQualifier(query))
+            return false;
+
+        if (string.IsNullOrWhiteSpace(query))
+            return false;
+
+        var value = query[0] == '@' ? query[1..] : query;
+        if (value.Length == 0 || !(char.IsLetter(value[0]) || value[0] == '_'))
+            return false;
+
+        return value.All(c => char.IsLetterOrDigit(c) || c == '_')
+            && CSharpReceiverQualifiedBareMemberFilterNames.Contains(value);
+    }
+
     /// <summary>
     /// Find callers for a referenced symbol.
     /// 指定シンボルを呼び出している呼び出し元を探す。
@@ -123,6 +160,7 @@ FROM symbol_references r
                 : " AND (r.symbol_name LIKE @query ESCAPE '\\' OR (f.lang = 'sql' AND r.symbol_name = sql_leaf_name(@aliasQuery) COLLATE NOCASE))";
         if (lang != null)
             sql += " AND f.lang = @lang";
+        sql += BuildCSharpBareMemberGraphReferenceFilter(query, lang, exact, contextSql, "f", "r");
         AppendPathFilters(ref sql, pathPatterns, excludePathPatterns, excludeTests);
         if (referenceKind == null)
         {
@@ -286,6 +324,7 @@ FROM symbol_references r
                 : " AND (r.symbol_name LIKE @query ESCAPE '\\' OR (f.lang = 'sql' AND r.symbol_name = sql_leaf_name(@aliasQuery) COLLATE NOCASE))";
         if (lang != null)
             groupedSql += " AND f.lang = @lang";
+        groupedSql += BuildCSharpBareMemberGraphReferenceFilter(query, lang, exact, contextSql, "f", "r");
         AppendPathFilters(ref groupedSql, pathPatterns, excludePathPatterns, excludeTests);
         if (referenceKind == null)
             groupedSql += $" GROUP BY f.path, f.lang, r.container_kind, r.container_name, r.symbol_name, r.file_id, r.line, r.column_number, {(rawKinds ? GetRawReferenceKindSql("r.reference_kind") : GetLogicalReferenceKindSql("r.reference_kind"))}";
@@ -396,6 +435,7 @@ FROM symbol_references r
                 : " AND (r.symbol_name LIKE @query ESCAPE '\\' OR (f.lang = 'sql' AND r.symbol_name = sql_leaf_name(@aliasQuery) COLLATE NOCASE))";
         if (lang != null)
             groupedSql += " AND f.lang = @lang";
+        groupedSql += BuildCSharpBareMemberGraphReferenceFilter(query, lang, exact, contextSql, "f", "r");
         AppendPathFilters(ref groupedSql, pathPatterns, excludePathPatterns, excludeTests);
         if (referenceKind == null)
             groupedSql += $" GROUP BY f.path, f.lang, r.container_kind, r.container_name, r.symbol_name, r.file_id, r.line, r.column_number, {(rawKinds ? GetRawReferenceKindSql("r.reference_kind") : GetLogicalReferenceKindSql("r.reference_kind"))}";
@@ -980,6 +1020,7 @@ AND r.reference_kind IN {CallGraphReferenceKindsSql}
                   {nameCondition}";
         if (lang != null)
             sql += " AND f.lang = @lang";
+        sql += BuildCSharpBareMemberGraphReferenceFilter(symbolName, lang, exact: true, contextSql, "f", "r");
         AppendPathFilters(ref sql, pathPatterns, excludePathPatterns, excludeTests);
         sql += @"
                 GROUP BY f.path, f.lang, r.container_kind, r.container_name, r.symbol_name, r.reference_kind, r.file_id, r.line, r.column_number

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

@@ -1165,6 +1165,9 @@ private static bool HasInvalidCSharpReturnTypeSuffix(string? returnType)
             return true;
 
         var lastChar = trimmed[^1];
+        if (lastChar == ',' && !LooksLikeCSharpDeclaratorListReturnType(trimmed))
+            return true;
+
         if (lastChar is '<' or '=' or ':' or '+' or '-' or '/' or '%' or '!' or '&' or '|' or '^' or '~' or '.')
             return true;
 
@@ -1186,6 +1189,14 @@ private static bool HasInvalidCSharpReturnTypeSuffix(string? returnType)
         return lastToken is "as" or "is" or "return" or "throw" or "new";
     }
 
+    private static bool LooksLikeCSharpDeclaratorListReturnType(string returnType)
+    {
+        var withoutTrailingComma = returnType[..^1].TrimEnd();
+        var firstSegmentEnd = withoutTrailingComma.IndexOf(',');
+        var firstSegment = (firstSegmentEnd >= 0 ? withoutTrailingComma[..firstSegmentEnd] : withoutTrailingComma).Trim();
+        return firstSegment.Any(char.IsWhiteSpace);
+    }
+
     private static bool IsInsidePreviouslyEmittedCSharpMemberBody(
         string[] lines,
         List<SymbolRecord> symbols,

src/CodeIndex/Lsp/LspServer.cs

@@ -24,6 +24,8 @@ internal sealed class LspServer : IDisposable
     private bool _exitRequested;
     private bool _exitRequestedBeforeShutdown;
 
+    private readonly record struct PositionTokenContext(string Token, string IndexedPath);
+
     public LspServer(DbReader reader, string version, JsonSerializerOptions jsonOptions, string? projectRoot = null)
     {
         _reader = reader;
@@ -153,11 +155,11 @@ private JsonArray DocumentSymbol(JsonElement root)
 
     private JsonArray Definition(JsonElement root)
     {
-        var query = ExtractPositionToken(root);
-        if (string.IsNullOrWhiteSpace(query))
+        var context = ExtractPositionToken(root);
+        if (context == null)
             return [];
 
-        var definitions = _reader.GetDefinitions(query, DefaultLimit, exact: true);
+        var definitions = ResolveLspDefinitions(context.Value);
         var array = new JsonArray();
         foreach (var definition in definitions)
             array.Add(ToLocation(definition.Path, definition.StartLine, 1, definition.EndLine, 1));
@@ -166,18 +168,53 @@ private JsonArray Definition(JsonElement root)
 
     private JsonArray References(JsonElement root)
     {
-        var query = ExtractPositionToken(root);
-        if (string.IsNullOrWhiteSpace(query))
+        var context = ExtractPositionToken(root);
+        if (context == null)
             return [];
 
-        var analysis = _reader.AnalyzeSymbol(query, DefaultLimit, exact: true);
+        var analysis = ResolveLspReferences(context.Value);
         var array = new JsonArray();
         foreach (var reference in analysis.References)
-            array.Add(ToLocation(reference.Path, reference.Line, Math.Max(reference.Column, 1), reference.Line, Math.Max(reference.Column, 1) + Math.Max(query.Length, 1)));
+            array.Add(ToLocation(reference.Path, reference.Line, Math.Max(reference.Column, 1), reference.Line, Math.Max(reference.Column, 1) + Math.Max(context.Value.Token.Length, 1)));
         return array;
     }
 
-    private string? ExtractPositionToken(JsonElement root)
+    private List<DefinitionResult> ResolveLspDefinitions(PositionTokenContext context)
+    {
+        var localDefinitions = _reader.GetDefinitions(context.Token, DefaultLimit, exact: true, pathPatterns: [context.IndexedPath]);
+        if (localDefinitions.Count > 0)
+            return localDefinitions;
+
+        var workspaceDefinitions = _reader.GetDefinitions(context.Token, DefaultLimit, exact: true);
+        return HasSingleLspDefinitionTarget(workspaceDefinitions) ? workspaceDefinitions : [];
+    }
+
+    private SymbolAnalysisResult ResolveLspReferences(PositionTokenContext context)
+    {
+        var localDefinitions = _reader.GetDefinitions(context.Token, DefaultLimit, exact: true, pathPatterns: [context.IndexedPath]);
+        if (localDefinitions.Count > 0)
+            return _reader.AnalyzeSymbol(context.Token, DefaultLimit, pathPatterns: [context.IndexedPath], exact: true);
+
+        var workspaceDefinitions = _reader.GetDefinitions(context.Token, DefaultLimit, exact: true);
+        if (workspaceDefinitions.Count == 0 || !HasSingleLspDefinitionTarget(workspaceDefinitions))
+            return _reader.AnalyzeSymbol(context.Token, DefaultLimit, pathPatterns: [context.IndexedPath], exact: true);
+
+        return _reader.AnalyzeSymbol(context.Token, DefaultLimit, exact: true);
+    }
+
+    private static bool HasSingleLspDefinitionTarget(IReadOnlyList<DefinitionResult> definitions)
+    {
+        if (definitions.Count <= 1)
+            return true;
+
+        var firstKey = BuildLspDefinitionTargetKey(definitions[0]);
+        return definitions.Skip(1).All(definition => string.Equals(BuildLspDefinitionTargetKey(definition), firstKey, StringComparison.Ordinal));
+    }
+
+    private static string BuildLspDefinitionTargetKey(DefinitionResult definition)
+        => string.Join('\0', definition.Path, definition.Kind, definition.ContainerKind, definition.ContainerName, definition.Name);
+
+    private PositionTokenContext? ExtractPositionToken(JsonElement root)
     {
         var path = GetDocumentPath(root);
         var line = GetInt32(root, "params", "position", "line");
@@ -198,7 +235,8 @@ private JsonArray References(JsonElement root)
         if (!TryReadPositionLine(indexedFullPath, line, out var sourceLine))
             return null;
 
-        return ExtractTokenAtUtf16Position(sourceLine, character);
+        var token = ExtractTokenAtUtf16Position(sourceLine, character);
+        return string.IsNullOrWhiteSpace(token) ? null : new PositionTokenContext(token, indexedPath);
     }
 
     private static bool TryReadPositionLine(string path, int targetLine, out string sourceLine)

tests/CodeIndex.Tests/DbReaderTests.cs

@@ -5312,6 +5312,42 @@ public void Run()
         Assert.Equal(1, dependency.ReferenceCount);
     }
 
+    [Fact]
+    public void GraphQueries_CsharpBareMemberCallersSkipReceiverQualifiedCalls()
+    {
+        InsertIndexedFile("src/common_member_graph_fixture.cs", "csharp",
+            """
+            using System.Text.Json;
+
+            public class Caller
+            {
+                private string GetString() => "";
+
+                public void Run(LocalApi api, JsonElement json)
+                {
+                    api.GetString();
+                    json.GetString();
+                    GetString();
+                }
+            }
+
+            public class LocalApi
+            {
+                public string GetString() => "";
+            }
+            """);
+
+        var callers = _reader.GetCallers("GetString", lang: "csharp", exact: true, pathPatterns: ["common_member_graph_fixture"]);
+
+        var caller = Assert.Single(callers);
+        Assert.Equal("Run", caller.CallerName);
+        Assert.Equal(1, caller.ReferenceCount);
+        Assert.Equal(1, _reader.CountCallers("GetString", lang: "csharp", exact: true, pathPatterns: ["common_member_graph_fixture"]));
+        var total = _reader.CountCallersTotal("GetString", lang: "csharp", exact: true, pathPatterns: ["common_member_graph_fixture"]);
+        Assert.Equal(1, total.Count);
+        Assert.Equal(1, total.FileCount);
+    }
+
     [Fact]
     public void SqlQualifiedNames_AlignGraphReadersHotspotsAndUnused()
     {