修补程序与系统的修补程序一起应用，但被git-apply拒绝

Question

I'm trying to understand how does git apply unified diffs.

I wrote the following "identity" patch:

--- a/js/controllers.js
+++ b/js/controllers.js
@@ -15,3 +15,3 @@
-  '$location',
-  function ($scope, $routeParams, $location) {
-    doSomething();
+  '$location',
+  function ($scope, $routeParams, $location) {
+    doSomething();

The system's patch command applies this patch with success while git-apply gives the following output:

error: patch failed: [...]js/controllers.js:15
error: [...]js/controllers.js: patch does not apply

I don't understand why.

Answer 1

Your patch has no context. diff would have included a few unmodified lines before and after the changes as well. From the git apply documentation:

--unidiff-zero

By default, git apply expects that the patch being applied is a unified diff with at least one line of context. This provides good safety measures, but breaks down when applying a diff generated with --unified=0 . To bypass these checks use --unidiff-zero .

Note, for the reasons stated above usage of context-free patches is discouraged.