util: Preserve symlinks when copying

Currently the `copy_all` function resolves all symlinks and crashes on
broken symlinks. Instead it should copy symlinks as symlinks.

Fixes: https://pagure.io/pungi/issue/1084
Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>

pungi/util.py

@@ -564,7 +564,11 @@ def copy_all(src, dest):
         if os.path.isdir(source):
             shutil.copytree(source, destination)
         else:
-            shutil.copy2(source, destination)
+            if os.path.islink(source):
+                # It's a symlink, we should preserve it instead of resolving.
+                os.symlink(os.readlink(source), destination)
+            else:
+                shutil.copy2(source, destination)
 
     return recursive_file_list(src)
 

tests/test_util.py

@@ -753,5 +753,32 @@ class TestParseKojiEvent(PungiTestCase):
             util.parse_koji_event(self.topdir)
 
 
+class TestCopyAll(PungiTestCase):
+
+    def setUp(self):
+        super(TestCopyAll, self).setUp()
+        self.src = os.path.join(self.topdir, "src")
+        self.dst = os.path.join(self.topdir, "dst")
+        util.makedirs(self.src)
+
+    def test_preserve_symlink(self):
+        touch(os.path.join(self.src, "target"))
+        os.symlink("target", os.path.join(self.src, "symlink"))
+
+        util.copy_all(self.src, self.dst)
+
+        self.assertTrue(os.path.isfile(os.path.join(self.dst, "target")))
+        self.assertTrue(os.path.islink(os.path.join(self.dst, "symlink")))
+        self.assertEqual(os.readlink(os.path.join(self.dst, "symlink")), "target")
+
+    def test_copy_broken_symlink(self):
+        os.symlink("broken", os.path.join(self.src, "symlink"))
+
+        util.copy_all(self.src, self.dst)
+
+        self.assertTrue(os.path.islink(os.path.join(self.dst, "symlink")))
+        self.assertEqual(os.readlink(os.path.join(self.dst, "symlink")), "broken")
+
+
 if __name__ == "__main__":
     unittest.main()