diff --git a/tests/Unit/GitLsRemoteParsingTest.php b/tests/Unit/GitLsRemoteParsingTest.php
index f4fd2e881..fce51a210 100644
--- a/tests/Unit/GitLsRemoteParsingTest.php
+++ b/tests/Unit/GitLsRemoteParsingTest.php
@@ -5,7 +5,7 @@
 it('extracts commit SHA from git ls-remote output without warnings', function () {
     $output = "196d3df7665359a8c8fa3329a6bcde0267e550bf\trefs/heads/master";
 
-    preg_match('/([0-9a-f]{40})\s*\t/', $output, $matches);
+    preg_match('/\b([0-9a-fA-F]{40})(?=\s*\t)/', $output, $matches);
     $commit = $matches[1] ?? null;
 
     expect($commit)->toBe('196d3df7665359a8c8fa3329a6bcde0267e550bf');
@@ -14,7 +14,7 @@
 it('extracts commit SHA from git ls-remote output with redirect warning on separate line', function () {
     $output = "warning: redirecting to https://tangled.org/@tangled.org/core/\n196d3df7665359a8c8fa3329a6bcde0267e550bf\trefs/heads/master";
 
-    preg_match('/([0-9a-f]{40})\s*\t/', $output, $matches);
+    preg_match('/\b([0-9a-fA-F]{40})(?=\s*\t)/', $output, $matches);
     $commit = $matches[1] ?? null;
 
     expect($commit)->toBe('196d3df7665359a8c8fa3329a6bcde0267e550bf');
@@ -24,7 +24,7 @@
     // This is the actual format from tangled.sh - warning and result on same line, no newline
     $output = "warning: redirecting to https://tangled.org/@tangled.org/core/196d3df7665359a8c8fa3329a6bcde0267e550bf\trefs/heads/master";
 
-    preg_match('/([0-9a-f]{40})\s*\t/', $output, $matches);
+    preg_match('/\b([0-9a-fA-F]{40})(?=\s*\t)/', $output, $matches);
     $commit = $matches[1] ?? null;
 
     expect($commit)->toBe('196d3df7665359a8c8fa3329a6bcde0267e550bf');
@@ -33,7 +33,7 @@
 it('extracts commit SHA from git ls-remote output with multiple warning lines', function () {
     $output = "warning: redirecting to https://example.org/repo/\ninfo: some other message\n196d3df7665359a8c8fa3329a6bcde0267e550bf\trefs/heads/main";
 
-    preg_match('/([0-9a-f]{40})\s*\t/', $output, $matches);
+    preg_match('/\b([0-9a-fA-F]{40})(?=\s*\t)/', $output, $matches);
     $commit = $matches[1] ?? null;
 
     expect($commit)->toBe('196d3df7665359a8c8fa3329a6bcde0267e550bf');
@@ -42,8 +42,36 @@
 it('handles git ls-remote output with extra whitespace', function () {
     $output = "  196d3df7665359a8c8fa3329a6bcde0267e550bf  \trefs/heads/master";
 
-    preg_match('/([0-9a-f]{40})\s*\t/', $output, $matches);
+    preg_match('/\b([0-9a-fA-F]{40})(?=\s*\t)/', $output, $matches);
     $commit = $matches[1] ?? null;
 
     expect($commit)->toBe('196d3df7665359a8c8fa3329a6bcde0267e550bf');
 });
+
+it('extracts commit SHA with uppercase letters and normalizes to lowercase', function () {
+    $output = "196D3DF7665359A8C8FA3329A6BCDE0267E550BF\trefs/heads/master";
+
+    preg_match('/\b([0-9a-fA-F]{40})(?=\s*\t)/', $output, $matches);
+    $commit = $matches[1] ?? null;
+
+    // Git SHAs are case-insensitive, so we normalize to lowercase for comparison
+    expect(strtolower($commit))->toBe('196d3df7665359a8c8fa3329a6bcde0267e550bf');
+});
+
+it('returns null when no commit SHA is present in output', function () {
+    $output = "warning: redirecting to https://example.org/repo/\nError: repository not found";
+
+    preg_match('/\b([0-9a-fA-F]{40})(?=\s*\t)/', $output, $matches);
+    $commit = $matches[1] ?? null;
+
+    expect($commit)->toBeNull();
+});
+
+it('returns null when output has tab but no valid SHA', function () {
+    $output = "invalid-sha-format\trefs/heads/master";
+
+    preg_match('/\b([0-9a-fA-F]{40})(?=\s*\t)/', $output, $matches);
+    $commit = $matches[1] ?? null;
+
+    expect($commit)->toBeNull();
+});