Teach "git apply" to prepend a prefix with "--root=<root>"

With "git apply --root=<root>", all file names in the patch are prepended
with <root>.  If a "-p" value was given, the paths are stripped _before_
prepending <root>.

Wished for by HPA.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/git-apply.txt b/Documentation/git-apply.txt
index c834763..63fce53 100644 (file)
--- a/Documentation/git-apply.txt
+++ b/Documentation/git-apply.txt
@@ -14,7 +14,7 @@ SYNOPSIS
          [--allow-binary-replacement | --binary] [--reject] [-z]
          [-pNUM] [-CNUM] [--inaccurate-eof] [--cached]
          [--whitespace=<nowarn|warn|fix|error|error-all>]
-         [--exclude=PATH] [--verbose] [<patch>...]
+         [--exclude=PATH] [--root=<root>] [--verbose] [<patch>...]
 
 DESCRIPTION
 -----------
@@ -177,6 +177,10 @@ behavior:
        current patch being applied will be printed. This option will cause
        additional information to be reported.
 
+--root=<root>::
+       Prepend <root> to all filenames.  If a "-p" argument was passed, too,
+       it is applied before prepending the new root.
+
 Configuration
 -------------
 

diff --git a/builtin-apply.c b/builtin-apply.c
index c497889..bf52896 100644 (file)
--- a/builtin-apply.c
+++ b/builtin-apply.c
@@ -57,6 +57,8 @@ static int whitespace_error;
 static int squelch_whitespace_errors = 5;
 static int applied_after_fixing_ws;
 static const char *patch_input_file;
+static const char *root;
+static int root_len;
 
 static void parse_whitespace_option(const char *option)
 {
@@ -331,6 +333,8 @@ static char *find_name(const char *line, char *def, int p_value, int terminate)
                                 */
                                strbuf_remove(&name, 0, cp - name.buf);
                                free(def);
+                               if (root)
+                                       strbuf_insert(&name, 0, root, root_len);
                                return strbuf_detach(&name, NULL);
                        }
                }
@@ -369,6 +373,14 @@ static char *find_name(const char *line, char *def, int p_value, int terminate)
                free(def);
        }
 
+       if (root) {
+               char *ret = xmalloc(root_len + len + 1);
+               strcpy(ret, root);
+               memcpy(ret + root_len, start, len);
+               ret[root_len + len] = '\0';
+               return ret;
+       }
+
        return xmemdupz(start, len);
 }
 
@@ -3118,6 +3130,18 @@ int cmd_apply(int argc, const char **argv, const char *unused_prefix)
                        inaccurate_eof = 1;
                        continue;
                }
+               if (!strncmp(arg, "--root=", strlen("--root="))) {
+                       arg += strlen("--root=");
+                       root_len = strlen(arg);
+                       if (root_len && arg[root_len + 1] != '/') {
+                               char *new_root;
+                               root = new_root = xmalloc(root_len + 2);
+                               strcpy(new_root, arg);
+                               strcpy(new_root + root_len++, "/");
+                       } else
+                               root = arg;
+                       continue;
+               }
                if (0 < prefix_length)
                        arg = prefix_filename(prefix, prefix_length, arg);
 

diff --git a/t/t4128-apply-root.sh b/t/t4128-apply-root.sh
new file mode 100755 (executable)
index 0000000..80b5af2
--- /dev/null
+++ b/t/t4128-apply-root.sh
@@ -0,0 +1,32 @@
+#!/bin/sh
+
+test_description='apply same filename'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+
+       mkdir -p some/sub/dir &&
+       echo Hello > some/sub/dir/file &&
+       git add some/sub/dir/file
+
+'
+
+cat > patch << EOF
+diff a/bla/blub/dir/file b/bla/blub/dir/file
+--- a/bla/blub/dir/file
++++ b/bla/blub/dir/file
+@@ -1,1 +1,1 @@
+-Hello
++Bello
+EOF
+
+test_expect_success 'apply --root -p --index' '
+
+       git apply --root=some/sub -p3 --index patch &&
+       test Bello = $(git show :some/sub/dir/file) &&
+       test Bello = $(cat some/sub/dir/file)
+
+'
+
+test_done