Return error if patch file passed to state file.patch is malformed

changelog/59806.fixed.md

@@ -0,0 +1 @@
+Return error if patch file passed to state file.patch is malformed.

salt/states/file.py

@@ -7265,6 +7265,10 @@ def _patch(patch_file, options=None, dry_run=False):
 
         pre_check = _patch(patch_file, patch_opts)
         if pre_check["retcode"] != 0:
+            if not os.path.exists(patch_rejects) or os.path.getsize(patch_rejects) == 0:
+                ret["comment"] = pre_check["stderr"]
+                ret["result"] = False
+                return ret
             # Try to reverse-apply hunks from rejects file using a dry-run.
             # If this returns a retcode of 0, we know that the patch was
             # already applied. Rejects are written from the base of the

tests/pytests/integration/states/test_file.py

@@ -929,6 +929,7 @@ def test_patch_directory_template(
             - source: {all_patch_template}
             - template: "jinja"
             - context: {context}
+            - strip: 1
         """.format(
         base_dir=tmp_path, all_patch_template=all_patch_template, context=context
     )
@@ -945,7 +946,7 @@ def test_patch_directory_template(
         # Check to make sure the patch was applied okay
         state_run = next(iter(ret.data.values()))
         assert state_run["result"] is True
-        assert state_run["comment"] == "Patch was already applied"
+        assert state_run["comment"] == "Patch successfully applied"
 
         # Re-run the state, should succeed and there should be a message about
         # a partially-applied hunk.