give placeholder name to document symbols for decls with empty names

Author: xdBronch

src/features/document_symbol.zig

@@ -203,8 +203,11 @@ fn convertSymbolsInternal(
     const to: []types.DocumentSymbol = symbol_buffer.items[prev_len..];
 
     for (from, to) |symbol, *out| {
+        // LSP spec requires that a symbol name is not empty or consisting only of whitespace
+        const name_is_empty = symbol.name.len == 0 or
+            std.mem.indexOfNone(u8, symbol.name, &std.ascii.whitespace) == null;
         out.* = .{
-            .name = symbol.name,
+            .name = if (name_is_empty) "<unnamed>" else symbol.name,
             .detail = symbol.detail,
             .kind = symbol.kind,
             // will be set later through the mapping below

tests/lsp_features/document_symbol.zig

@@ -93,6 +93,20 @@ test "nested struct with self" {
     );
 }
 
+test "empty decl names return non-empty document symbol" {
+    try testDocumentSymbol(
+        \\test "" {}
+        \\test "          " {}
+        \\const @"" = 0;
+        \\const @"   " = 0;
+    ,
+        \\Method <unnamed>
+        \\Method <unnamed>
+        \\Constant <unnamed>
+        \\Constant <unnamed>
+    );
+}
+
 fn testDocumentSymbol(source: []const u8, expected: []const u8) !void {
     var ctx: Context = try .init();
     defer ctx.deinit();