update-index --again

After running 'git-update-index' for some paths, you may want to
do the update on the same set of paths again.

The new flag --again checks the paths whose index entries are
are different from the HEAD commit and updates them from the
working tree contents.

This was brought up by Carl Worth on #git.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/Documentation/git-update-index.txt b/Documentation/git-update-index.txt
index 57177c7..d043e86 100644 (file)
--- a/Documentation/git-update-index.txt
+++ b/Documentation/git-update-index.txt
@@ -15,7 +15,7 @@ SYNOPSIS
             [--cacheinfo <mode> <object> <file>]\*
             [--chmod=(+|-)x]
             [--assume-unchanged | --no-assume-unchanged]
-            [--really-refresh] [--unresolve]
+            [--really-refresh] [--unresolve] [--again]
             [--info-only] [--index-info]
             [-z] [--stdin]
             [--verbose]
@@ -80,6 +80,10 @@ OPTIONS
        filesystem that has very slow lstat(2) system call
        (e.g. cifs).
 
+--again::
+       Runs `git-update-index` itself on the paths whose index
+       entries are different from those from the `HEAD` commit.
+
 --unresolve::
        Restores the 'unmerged' or 'needs updating' state of a
        file during a merge if it was cleared by accident.

diff --git a/t/t2101-update-index-reupdate.sh b/t/t2101-update-index-reupdate.sh
new file mode 100755 (executable)
index 0000000..5c505c6
--- /dev/null
+++ b/t/t2101-update-index-reupdate.sh
@@ -0,0 +1,73 @@
+#!/bin/sh
+#
+# Copyright (c) 2006 Junio C Hamano
+#
+
+test_description='git-update-index --again test.
+'
+
+. ./test-lib.sh
+
+test_expect_success 'update-index --add' \
+       'echo hello world >file1 &&
+        echo goodbye people >file2 &&
+        git-update-index --add file1 file2 &&
+        git-ls-files -s >current &&
+        cmp current - <<\EOF
+100644 3b18e512dba79e4c8300dd08aeb37f8e728b8dad 0      file1
+100644 9db8893856a8a02eaa73470054b7c1c5a7c82e47 0      file2
+EOF'
+
+test_expect_success 'update-index --again' \
+       'rm -f file1 &&
+       echo hello everybody >file2 &&
+       if git-update-index --again
+       then
+               echo should have refused to remove file1
+               exit 1
+       else
+               echo happy - failed as expected
+       fi &&
+        git-ls-files -s >current &&
+        cmp current - <<\EOF
+100644 3b18e512dba79e4c8300dd08aeb37f8e728b8dad 0      file1
+100644 9db8893856a8a02eaa73470054b7c1c5a7c82e47 0      file2
+EOF'
+
+test_expect_success 'update-index --remove --again' \
+       'git-update-index --remove --again &&
+        git-ls-files -s >current &&
+        cmp current - <<\EOF
+100644 0f1ae1422c2bf43f117d3dbd715c988a9ed2103f 0      file2
+EOF'
+
+test_expect_success 'first commit' 'git-commit -m initial'
+
+test_expect_success 'update-index again' \
+       'mkdir -p dir1 &&
+       echo hello world >dir1/file3 &&
+       echo goodbye people >file2 &&
+       git-update-index --add file2 dir1/file3 &&
+       echo hello everybody >file2
+       echo happy >dir1/file3 &&
+       git-update-index --again &&
+       git-ls-files -s >current &&
+       cmp current - <<\EOF
+100644 53ab446c3f4e42ce9bb728a0ccb283a101be4979 0      dir1/file3
+100644 0f1ae1422c2bf43f117d3dbd715c988a9ed2103f 0      file2
+EOF'
+
+test_expect_success 'update-index --update from subdir' \
+       'echo not so happy >file2 &&
+       cd dir1 &&
+       cat ../file2 >file3 &&
+       git-update-index --again &&
+       cd .. &&
+       git-ls-files -s >current &&
+       cmp current - <<\EOF
+100644 d7fb3f695f06c759dbf3ab00046e7cc2da22d10f 0      dir1/file3
+100644 0f1ae1422c2bf43f117d3dbd715c988a9ed2103f 0      file2
+EOF'
+
+test_done
+

diff --git a/update-index.c b/update-index.c
index d63f8ac..5496d68 100644 (file)
--- a/update-index.c
+++ b/update-index.c
@@ -476,7 +476,7 @@ static void read_index_info(int line_termination)
 }
 
 static const char update_index_usage[] =
-"git-update-index [-q] [--add] [--replace] [--remove] [--unmerged] [--refresh] [--really-refresh] [--cacheinfo] [--chmod=(+|-)x] [--assume-unchanged] [--info-only] [--force-remove] [--stdin] [--index-info] [--unresolve] [--ignore-missing] [-z] [--verbose] [--] <file>...";
+"git-update-index [-q] [--add] [--replace] [--remove] [--unmerged] [--refresh] [--really-refresh] [--cacheinfo] [--chmod=(+|-)x] [--assume-unchanged] [--info-only] [--force-remove] [--stdin] [--index-info] [--unresolve] [--again] [--ignore-missing] [-z] [--verbose] [--] <file>...";
 
 static unsigned char head_sha1[20];
 static unsigned char merge_head_sha1[20];
@@ -491,11 +491,13 @@ static struct cache_entry *read_one_ent(const char *which,
        struct cache_entry *ce;
 
        if (get_tree_entry(ent, path, sha1, &mode)) {
-               error("%s: not in %s branch.", path, which);
+               if (which)
+                       error("%s: not in %s branch.", path, which);
                return NULL;
        }
        if (mode == S_IFDIR) {
-               error("%s: not a blob in %s branch.", path, which);
+               if (which)
+                       error("%s: not a blob in %s branch.", path, which);
                return NULL;
        }
        size = cache_entry_size(namelen);
@@ -600,6 +602,47 @@ static int do_unresolve(int ac, const char **av,
        return err;
 }
 
+static int do_reupdate(int ac, const char **av,
+                      const char *prefix, int prefix_length)
+{
+       /* Read HEAD and run update-index on paths that are
+        * merged and already different between index and HEAD.
+        */
+       int pos;
+       int has_head = 1;
+
+       if (read_ref(git_path("HEAD"), head_sha1))
+               /* If there is no HEAD, that means it is an initial
+                * commit.  Update everything in the index.
+                */
+               has_head = 0;
+ redo:
+       for (pos = 0; pos < active_nr; pos++) {
+               struct cache_entry *ce = active_cache[pos];
+               struct cache_entry *old = NULL;
+               int save_nr;
+               if (ce_stage(ce))
+                       continue;
+               if (has_head)
+                       old = read_one_ent(NULL, head_sha1,
+                                          ce->name, ce_namelen(ce), 0);
+               if (old && ce->ce_mode == old->ce_mode &&
+                   !memcmp(ce->sha1, old->sha1, 20)) {
+                       free(old);
+                       continue; /* unchanged */
+               }
+               /* Be careful.  The working tree may not have the
+                * path anymore, in which case, under 'allow_remove',
+                * or worse yet 'allow_replace', active_nr may decrease.
+                */
+               save_nr = active_nr;
+               update_one(ce->name + prefix_length, prefix, prefix_length);
+               if (save_nr != active_nr)
+                       goto redo;
+       }
+       return 0;
+}
+
 int main(int argc, const char **argv)
 {
        int i, newfd, entries, has_errors = 0, line_termination = '\n';
@@ -717,6 +760,13 @@ int main(int argc, const char **argv)
                                        active_cache_changed = 0;
                                goto finish;
                        }
+                       if (!strcmp(path, "--again")) {
+                               has_errors = do_reupdate(argc - i, argv + i,
+                                                        prefix, prefix_length);
+                               if (has_errors)
+                                       active_cache_changed = 0;
+                               goto finish;
+                       }
                        if (!strcmp(path, "--ignore-missing")) {
                                not_new = 1;
                                continue;