Fix: should noop if info array has no values (closes #14)

Author: JPeer264

__tests__/test.spec.ts

@@ -56,6 +56,16 @@ test('unknown commit hash', () => {
   expect(!!latestInfo.error).toBe(true);
 });
 
+test('check up to date', () => {
+  const mergeInfo = gitCommitInfo({
+    cwd: path.join(fixtures, 'upToDate'),
+    commit: '31107b9051efe17e57c583937e027993860b11a9',
+  });
+
+  expect(mergeInfo.commit).toBe('31107b9051efe17e57c583937e027993860b11a9');
+  expect(mergeInfo.message).toBe('Initial commit');
+});
+
 test('merge conflict - named automatically', () => {
   const mergeInfo = gitCommitInfo({
     cwd: path.join(fixtures, 'merge'),

index.ts

@@ -39,7 +39,7 @@ const gitCommitInfo = (options: GitCommitInfoOptions = {}): GitCommitInfoResult
     const info = stdout
       .split('\n')
       .filter((entry) => entry.length !== 0);
-    const mergeIndex = info[1].indexOf('Merge') === -1 ? 0 : 1;
+    const mergeIndex = info[1]?.indexOf('Merge') === -1 ? 0 : 1;
 
     const hash = (new RegExp(regex).exec(info[0]) || [])[1];
     const shortHash = hash.slice(0, 7);