Fix missing matchedText key in JSON result

src/api.test.ts

@@ -146,6 +146,28 @@ describe("fetchAllResults", () => {
     expect(results[0].textMatches[0].matches[0].col).toBe(1);
   });
 
+  it("derives segment text from fragment when GitHub omits match text", async () => {
+    const fakeItem = {
+      path: "package.json",
+      html_url: "https://github.com/org/repo/blob/main/package.json",
+      repository: { full_name: "org/repo", archived: false },
+      text_matches: [
+        {
+          fragment: '{"dependencies":{"react-dom":"18.3.1"}}',
+          matches: [{ indices: [18, 27] }],
+        },
+      ],
+    };
+    globalThis.fetch = (async () =>
+      new Response(JSON.stringify({ items: [fakeItem], total_count: 1 }), {
+        status: 200,
+        headers: { "content-type": "application/json" },
+      })) as typeof fetch;
+
+    const results = await fetchAllResults("react-dom filename:package.json", "org", "tok");
+    expect(results[0].textMatches[0].matches[0].text).toBe("react-dom");
+  });
+
   it("marks archived repos correctly", async () => {
     const fakeItem = {
       path: "lib/old.ts",

src/api.ts

@@ -22,6 +22,18 @@ interface RawCodeItem {
   text_matches?: RawTextMatch[];
 }
 
+function deriveSegmentText(
+  fragment: string,
+  indices: [number, number],
+  providedText?: string,
+): string {
+  if (providedText !== undefined) return providedText;
+  const [rawStart, rawEnd] = indices;
+  const start = Math.max(0, Math.min(rawStart, fragment.length));
+  const end = Math.max(start, Math.min(rawEnd, fragment.length));
+  return fragment.slice(start, end);
+}
+
 interface SearchCodeResponse {
   items: RawCodeItem[];
   total_count: number;
@@ -287,7 +299,7 @@ export async function fetchAllResults(
             const indices = seg.indices;
             const { line: fragLine, col } = segmentLineCol(fragment, indices[0]);
             const line = fragmentStartLine + fragLine - 1;
-            return { text: seg.text ?? "", indices, line, col };
+            return { text: deriveSegmentText(fragment, indices, seg.text), indices, line, col };
           }),
         };
       }),

src/output.test.ts

@@ -622,7 +622,7 @@ describe("buildJsonOutput — line/col fields", () => {
   });
 
   it("omits matchedText when seg.text is an empty string", () => {
-    // api.ts normalizes missing segment text to "" — matchedText must not be emitted
+    // Empty segment text should not emit matchedText in JSON output.
     const groups: RepoGroup[] = [
       {
         repoFullName: "myorg/repoA",