Fix JSDoc comment formatting with tab indentation (#1900)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: jakebailey <5341706+jakebailey@users.noreply.github.com>

Author: Copilot

internal/format/comment_test.go

@@ -64,6 +64,43 @@ func TestCommentFormatting(t *testing.T) {
 		assert.Check(t, !contains(secondFormatted, " sync x()"), "should not corrupt async to sync")
 		assert.Check(t, contains(secondFormatted, "async"), "should preserve async keyword on second pass")
 	})
+
+	t.Run("format JSDoc with tab indentation", func(t *testing.T) {
+		t.Parallel()
+		ctx := format.WithFormatCodeSettings(t.Context(), &format.FormatCodeSettings{
+			EditorSettings: format.EditorSettings{
+				TabSize:                4,
+				IndentSize:             4,
+				BaseIndentSize:         0,
+				NewLineCharacter:       "\n",
+				ConvertTabsToSpaces:    false, // Use tabs
+				IndentStyle:            format.IndentStyleSmart,
+				TrimTrailingWhitespace: true,
+			},
+			InsertSpaceBeforeTypeAnnotation: core.TSTrue,
+		}, "\n")
+
+		// Original code with tab indentation (tabs represented as \t)
+		originalText := "class Foo {\n\t/**\n\t * @param {string} argument - This is a param description.\n\t */\n\texample(argument) {\nconsole.log(argument);\n\t}\n}"
+
+		sourceFile := parser.ParseSourceFile(ast.SourceFileParseOptions{
+			FileName: "/test.ts",
+			Path:     "/test.ts",
+		}, originalText, core.ScriptKindTS)
+
+		// Apply formatting
+		edits := format.FormatDocument(ctx, sourceFile)
+		formatted := applyBulkEdits(originalText, edits)
+
+		// Check that tabs come before spaces (not spaces before tabs)
+		// The comment lines should have format: tab followed by space and asterisk
+		// NOT: space followed by tab and asterisk
+		assert.Check(t, !contains(formatted, " \t*"), "should not have space before tab before asterisk")
+		assert.Check(t, contains(formatted, "\t *"), "should have tab before space before asterisk")
+
+		// Verify console.log is properly indented with tabs
+		assert.Check(t, contains(formatted, "\t\tconsole.log"), "console.log should be indented with two tabs")
+	})
 }
 
 func contains(s, substr string) bool {

internal/format/span.go

@@ -975,7 +975,7 @@ func getIndentationString(indentation int, options *FormatCodeSettings) string {
 		spaces := indentation - (tabs * options.TabSize)
 		res := strings.Repeat("\t", tabs)
 		if spaces > 0 {
-			res = strings.Repeat(" ", spaces) + res
+			res = res + strings.Repeat(" ", spaces)
 		}
 
 		return res