[fix] Recognize full-index git patch format correctly (#45)

* Validate full index patch format

Signed-off-by: Uilian Ries <uilianr@jfrog.com>

* Add support for full-index patch format

Signed-off-by: Uilian Ries <uilianr@jfrog.com>

* Update validation for Windows

Signed-off-by: Uilian Ries <uilianr@jfrog.com>

---------

Signed-off-by: Uilian Ries <uilianr@jfrog.com>

Author: uilianries

patch_ng.py

@@ -707,7 +707,9 @@ def _detect_type(self, p):
           break
       if p.header[idx].startswith(b'diff --git a/'):
         if (idx+1 < len(p.header)
-            and re.match(b'(?:index \\w{7}..\\w{7} \\d{6}|new file mode \\d*)', p.header[idx+1])):
+            and re.match(
+              b'(?:index \\w{4,40}\\.\\.\\w{4,40}(?: \\d{6})?|new file mode \\d+|deleted file mode \\d+)',
+              p.header[idx+1])):
           if DVCS:
             return GIT
 

tests/patchformat/create.patch

@@ -0,0 +1,20 @@
+From 8cacee878aff9a79603c87366d3eeefa68d80cf3 Mon Sep 17 00:00:00 2001
+From: John Doe <john.doe@email.com>
+Date: Wed, 1 Oct 2025 10:59:19 +0200
+Subject: [PATCH] Add quotes.txt
+
+Signed-off-by: John Doe <john.doe@email.com>
+---
+ quotes.txt | 1 +
+ 1 file changed, 1 insertion(+)
+ create mode 100644 quotes.txt
+
+diff --git a/quotes.txt b/quotes.txt
+new file mode 100644
+index 0000000000000000000000000000000000000000..edcfcc5846847fffa4986b8437f1d7a3bd8aa8cf
+--- /dev/null
++++ b/quotes.txt
+@@ -0,0 +1 @@
++habita fides ipsam plerumque obligat fidem.
+--
+2.51.0

tests/patchformat/remove.patch

@@ -0,0 +1,20 @@
+From 22751ffae72c0b955b55e68ec0e25a80e434e890 Mon Sep 17 00:00:00 2001
+From: John Doe <john.doe@email.com>
+Date: Wed, 1 Oct 2025 10:59:47 +0200
+Subject: [PATCH] Remove quotes.txt
+
+Signed-off-by: John Doe <john.doe@email.com>
+---
+ quotes.txt | 1 -
+ 1 file changed, 1 deletion(-)
+ delete mode 100644 quotes.txt
+
+diff --git a/quotes.txt b/quotes.txt
+deleted file mode 100644
+index 22174d6b96bbdd674d38f8be446d22758f996aba..0000000000000000000000000000000000000000
+--- a/quotes.txt
++++ /dev/null
+@@ -1 +0,0 @@
+-Si vis pacem cole justitiam.
+--
+2.51.0

tests/patchformat/update.patch

@@ -0,0 +1,19 @@
+From 3360e00554544de3a68a227ac9eff5bb687da723 Mon Sep 17 00:00:00 2001
+From: John Doe <john.doe@email.com>
+Date: Wed, 1 Oct 2025 10:59:37 +0200
+Subject: [PATCH] Update quote
+
+Signed-off-by: John Doe <john.doe@email.com>
+---
+ quotes.txt | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/quotes.txt b/quotes.txt
+index edcfcc5846847fffa4986b8437f1d7a3bd8aa8cf..22174d6b96bbdd674d38f8be446d22758f996aba 100644
+--- a/quotes.txt
++++ b/quotes.txt
+@@ -1 +1 @@
+-habita fides ipsam plerumque obligat fidem.
++Si vis pacem cole justitiam.
+--
+2.51.0

tests/run_tests.py

@@ -518,6 +518,47 @@ def test_pathstrip(self):
         self.assertEqual(patch_ng.pathstrip(b'path/name.diff', 1), b'name.diff')
         self.assertEqual(patch_ng.pathstrip(b'path/name.diff', 0), b'path/name.diff')
 
+
+class TestPatchFormat(unittest.TestCase):
+    def setUp(self):
+        self.save_cwd = os.getcwd()
+        self.tmpdir = mkdtemp(prefix=self.__class__.__name__)        
+        shutil.copytree(join(TESTS, 'patchformat'), join(self.tmpdir, 'patchformat'))
+
+    def tearDown(self):
+        os.chdir(self.save_cwd)
+        remove_tree_force(self.tmpdir)
+
+    def test_handle_full_index_patch_format(self):
+        """Test that a full index patch format is handled correctly
+
+        When parsing a git patch with a full index line (40 hex chars),
+        the patch type should be detected as GIT and the patch should be
+        applied correctly (create, update, remove a file).
+        """
+
+        os.chdir(self.tmpdir)
+        pto = patch_ng.fromfile(join(self.tmpdir, 'patchformat', 'create.patch'))
+        self.assertEqual(len(pto), 1)
+        self.assertEqual(pto.items[0].type, patch_ng.GIT)
+        self.assertTrue(pto.apply())
+        self.assertTrue(os.path.exists(join(self.tmpdir, 'quotes.txt')))
+
+        pto = patch_ng.fromfile(join(self.tmpdir, 'patchformat', 'update.patch'))
+        self.assertEqual(len(pto), 1)
+        self.assertEqual(pto.items[0].type, patch_ng.GIT)
+        self.assertTrue(pto.apply())
+        with open(join(self.tmpdir, 'quotes.txt'), 'rb') as f:
+            content = f.read()
+            self.assertTrue(b'Si vis pacem cole justitiam.' in content)
+
+        pto = patch_ng.fromfile(join(self.tmpdir, 'patchformat', 'remove.patch'))
+        self.assertEqual(len(pto), 1)
+        self.assertEqual(pto.items[0].type, patch_ng.GIT)
+        self.assertTrue(pto.apply())
+        self.assertFalse(os.path.exists(join(self.tmpdir, 'quotes.txt')))
+
+
 def remove_tree_force(folder):
     for root, _, files in os.walk(folder):
         for it in files: