status: show more info than "currently not on any branch"

When a remote ref or a tag is checked out, HEAD is automatically
detached. There is no user-friendly way to find out what ref is
checked out in this case. This patch digs in reflog for this
information and shows "HEAD detached from origin/master" or "HEAD
detached at v1.8.0" instead of "currently not on any branch".

When it cannot figure out the original ref, it shows an abbreviated
SHA-1. "Currently not on any branch" would never display (unless
reflog is pruned to near empty that the last checkout entry is lost).

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/t7406-submodule-update.sh b/t/t7406-submodule-update.sh
index 4975ec07ce614c8473f7f5638a008d7058730f06..50ac02028df0cc83e3f30cc73373ddf930634e3f 100755 (executable)
--- a/t/t7406-submodule-update.sh
+++ b/t/t7406-submodule-update.sh
@@ -664,8 +664,10 @@ test_expect_success 'submodule add properly re-creates deeper level submodules'
 
 test_expect_success 'submodule update properly revives a moved submodule' '
        (cd super &&
+        H=$(git rev-parse --short HEAD) &&
         git commit -am "pre move" &&
-        git status >expect&&
+        H2=$(git rev-parse --short HEAD) &&
+        git status | sed "s/$H/XXX/" >expect &&
         H=$(cd submodule2; git rev-parse HEAD) &&
         git rm --cached submodule2 &&
         rm -rf submodule2 &&
@@ -674,7 +676,7 @@ test_expect_success 'submodule update properly revives a moved submodule' '
         git config -f .gitmodules submodule.submodule2.path "moved/sub module"
         git commit -am "post move" &&
         git submodule update &&
-        git status >actual &&
+        git status | sed "s/$H2/XXX/" >actual &&
         test_cmp expect actual
        )
 '

diff --git a/t/t7512-status-help.sh b/t/t7512-status-help.sh
index 51ab89411f06aa200c27815b8642cb0c78caeba4..5adba4f5e4f2476a60bfe41c0246f7a5a72127b6 100755 (executable)
--- a/t/t7512-status-help.sh
+++ b/t/t7512-status-help.sh
@@ -76,7 +76,7 @@ test_expect_success 'status when rebase in progress before resolving conflicts'
        ONTO=$(git rev-parse --short HEAD^^) &&
        test_must_fail git rebase HEAD^ --onto HEAD^^ &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached at $ONTO
        # You are currently rebasing branch '\''rebase_conflicts'\'' on '\''$ONTO'\''.
        #   (fix conflicts and then run "git rebase --continue")
        #   (use "git rebase --skip" to skip this patch)
@@ -103,7 +103,7 @@ test_expect_success 'status when rebase in progress before rebase --continue' '
        echo three >main.txt &&
        git add main.txt &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached at $ONTO
        # You are currently rebasing branch '\''rebase_conflicts'\'' on '\''$ONTO'\''.
        #   (all conflicts fixed: run "git rebase --continue")
        #
@@ -135,7 +135,7 @@ test_expect_success 'status during rebase -i when conflicts unresolved' '
        ONTO=$(git rev-parse --short rebase_i_conflicts) &&
        test_must_fail git rebase -i rebase_i_conflicts &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached at $ONTO
        # You are currently rebasing branch '\''rebase_i_conflicts_second'\'' on '\''$ONTO'\''.
        #   (fix conflicts and then run "git rebase --continue")
        #   (use "git rebase --skip" to skip this patch)
@@ -161,7 +161,7 @@ test_expect_success 'status during rebase -i after resolving conflicts' '
        test_must_fail git rebase -i rebase_i_conflicts &&
        git add main.txt &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached at $ONTO
        # You are currently rebasing branch '\''rebase_i_conflicts_second'\'' on '\''$ONTO'\''.
        #   (all conflicts fixed: run "git rebase --continue")
        #
@@ -187,9 +187,10 @@ test_expect_success 'status when rebasing -i in edit mode' '
        export FAKE_LINES &&
        test_when_finished "git rebase --abort" &&
        ONTO=$(git rev-parse --short HEAD~2) &&
+       TGT=$(git rev-parse --short two_rebase_i) &&
        git rebase -i HEAD~2 &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $TGT
        # You are currently editing a commit while rebasing branch '\''rebase_i_edit'\'' on '\''$ONTO'\''.
        #   (use "git commit --amend" to amend the current commit)
        #   (use "git rebase --continue" once you are satisfied with your changes)
@@ -214,8 +215,9 @@ test_expect_success 'status when splitting a commit' '
        ONTO=$(git rev-parse --short HEAD~3) &&
        git rebase -i HEAD~3 &&
        git reset HEAD^ &&
+       TGT=$(git rev-parse --short HEAD) &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached at $TGT
        # You are currently splitting a commit while rebasing branch '\''split_commit'\'' on '\''$ONTO'\''.
        #   (Once your working directory is clean, run "git rebase --continue")
        #
@@ -243,10 +245,11 @@ test_expect_success 'status after editing the last commit with --amend during a
        export FAKE_LINES &&
        test_when_finished "git rebase --abort" &&
        ONTO=$(git rev-parse --short HEAD~3) &&
+       TGT=$(git rev-parse --short three_amend) &&
        git rebase -i HEAD~3 &&
        git commit --amend -m "foo" &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $TGT
        # You are currently editing a commit while rebasing branch '\''amend_last'\'' on '\''$ONTO'\''.
        #   (use "git commit --amend" to amend the current commit)
        #   (use "git rebase --continue" once you are satisfied with your changes)
@@ -276,7 +279,7 @@ test_expect_success 'status: (continue first edit) second edit' '
        git rebase -i HEAD~3 &&
        git rebase --continue &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $ONTO
        # You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
        #   (use "git commit --amend" to amend the current commit)
        #   (use "git rebase --continue" once you are satisfied with your changes)
@@ -298,7 +301,7 @@ test_expect_success 'status: (continue first edit) second edit and split' '
        git rebase --continue &&
        git reset HEAD^ &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $ONTO
        # You are currently splitting a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
        #   (Once your working directory is clean, run "git rebase --continue")
        #
@@ -325,7 +328,7 @@ test_expect_success 'status: (continue first edit) second edit and amend' '
        git rebase --continue &&
        git commit --amend -m "foo" &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $ONTO
        # You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
        #   (use "git commit --amend" to amend the current commit)
        #   (use "git rebase --continue" once you are satisfied with your changes)
@@ -347,7 +350,7 @@ test_expect_success 'status: (amend first edit) second edit' '
        git commit --amend -m "a" &&
        git rebase --continue &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $ONTO
        # You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
        #   (use "git commit --amend" to amend the current commit)
        #   (use "git rebase --continue" once you are satisfied with your changes)
@@ -370,7 +373,7 @@ test_expect_success 'status: (amend first edit) second edit and split' '
        git rebase --continue &&
        git reset HEAD^ &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $ONTO
        # You are currently splitting a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
        #   (Once your working directory is clean, run "git rebase --continue")
        #
@@ -398,7 +401,7 @@ test_expect_success 'status: (amend first edit) second edit and amend' '
        git rebase --continue &&
        git commit --amend -m "d" &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $ONTO
        # You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
        #   (use "git commit --amend" to amend the current commit)
        #   (use "git rebase --continue" once you are satisfied with your changes)
@@ -422,7 +425,7 @@ test_expect_success 'status: (split first edit) second edit' '
        git commit -m "e" &&
        git rebase --continue &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $ONTO
        # You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
        #   (use "git commit --amend" to amend the current commit)
        #   (use "git rebase --continue" once you are satisfied with your changes)
@@ -447,7 +450,7 @@ test_expect_success 'status: (split first edit) second edit and split' '
        git rebase --continue &&
        git reset HEAD^ &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $ONTO
        # You are currently splitting a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
        #   (Once your working directory is clean, run "git rebase --continue")
        #
@@ -477,7 +480,7 @@ test_expect_success 'status: (split first edit) second edit and amend' '
        git rebase --continue &&
        git commit --amend -m "h" &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached from $ONTO
        # You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
        #   (use "git commit --amend" to amend the current commit)
        #   (use "git rebase --continue" once you are satisfied with your changes)
@@ -572,8 +575,9 @@ test_expect_success 'status when bisecting' '
        git bisect start &&
        git bisect bad &&
        git bisect good one_bisect &&
-       cat >expected <<-\EOF &&
-       # Not currently on any branch.
+       TGT=$(git rev-parse --short two_bisect) &&
+       cat >expected <<-EOF &&
+       # HEAD detached at $TGT
        # You are currently bisecting branch '\''bisect'\''.
        #   (use "git bisect reset" to get back to the original branch)
        #
@@ -596,7 +600,7 @@ test_expect_success 'status when rebase conflicts with statushints disabled' '
        ONTO=$(git rev-parse --short HEAD^^) &&
        test_must_fail git rebase HEAD^ --onto HEAD^^ &&
        cat >expected <<-EOF &&
-       # Not currently on any branch.
+       # HEAD detached at $ONTO
        # You are currently rebasing branch '\''statushints_disabled'\'' on '\''$ONTO'\''.
        #
        # Unmerged paths:
@@ -662,5 +666,15 @@ test_expect_success 'status when cherry-picking after resolving conflicts' '
        test_i18ncmp expected actual
 '
 
+test_expect_success 'status showing detached from a tag' '
+       test_commit atag tagging &&
+       git checkout atag &&
+       cat >expected <<-\EOF
+       # HEAD detached at atag
+       nothing to commit (use -u to show untracked files)
+       EOF
+       git status --untracked-files=no >actual &&
+       test_i18ncmp expected actual
+'
 
 test_done

diff --git a/wt-status.c b/wt-status.c
index 40dced3ef980868d432a70457053abf6d886a153..32a51e1323e28a49f617be4b53e35416f52cb066 100644 (file)
--- a/wt-status.c
+++ b/wt-status.c
@@ -999,7 +999,73 @@ static char *read_and_strip_branch(const char *path)
        return NULL;
 }
 
-void wt_status_get_state(struct wt_status_state *state)
+struct grab_1st_switch_cbdata {
+       int found;
+       struct strbuf buf;
+       unsigned char nsha1[20];
+};
+
+static int grab_1st_switch(unsigned char *osha1, unsigned char *nsha1,
+                          const char *email, unsigned long timestamp, int tz,
+                          const char *message, void *cb_data)
+{
+       struct grab_1st_switch_cbdata *cb = cb_data;
+       const char *target = NULL, *end;
+
+       if (prefixcmp(message, "checkout: moving from "))
+               return 0;
+       message += strlen("checkout: moving from ");
+       target = strstr(message, " to ");
+       if (!target)
+               return 0;
+       target += strlen(" to ");
+       strbuf_reset(&cb->buf);
+       hashcpy(cb->nsha1, nsha1);
+       for (end = target; *end && *end != '\n'; end++)
+               ;
+       strbuf_add(&cb->buf, target, end - target);
+       cb->found = 1;
+       return 1;
+}
+
+static void wt_status_get_detached_from(struct wt_status_state *state)
+{
+       struct grab_1st_switch_cbdata cb;
+       struct commit *commit;
+       unsigned char sha1[20];
+       char *ref = NULL;
+
+       strbuf_init(&cb.buf, 0);
+       if (for_each_reflog_ent_reverse("HEAD", grab_1st_switch, &cb) <= 0) {
+               strbuf_release(&cb.buf);
+               return;
+       }
+
+       if (dwim_ref(cb.buf.buf, cb.buf.len, sha1, &ref) == 1 &&
+           /* sha1 is a commit? match without further lookup */
+           (!hashcmp(cb.nsha1, sha1) ||
+            /* perhaps sha1 is a tag, try to dereference to a commit */
+            ((commit = lookup_commit_reference_gently(sha1, 1)) != NULL &&
+             !hashcmp(cb.nsha1, commit->object.sha1)))) {
+               int ofs;
+               if (!prefixcmp(ref, "refs/tags/"))
+                       ofs = strlen("refs/tags/");
+               else if (!prefixcmp(ref, "refs/remotes/"))
+                       ofs = strlen("refs/remotes/");
+               else
+                       ofs = 0;
+               state->detached_from = xstrdup(ref + ofs);
+       } else
+               state->detached_from =
+                       xstrdup(find_unique_abbrev(cb.nsha1, DEFAULT_ABBREV));
+       hashcpy(state->detached_sha1, cb.nsha1);
+
+       free(ref);
+       strbuf_release(&cb.buf);
+}
+
+void wt_status_get_state(struct wt_status_state *state,
+                        int get_detached_from)
 {
        struct stat st;
 
@@ -1029,6 +1095,9 @@ void wt_status_get_state(struct wt_status_state *state)
                state->bisect_in_progress = 1;
                state->branch = read_and_strip_branch("BISECT_START");
        }
+
+       if (get_detached_from)
+               wt_status_get_detached_from(state);
 }
 
 static void wt_status_print_state(struct wt_status *s,
@@ -1054,7 +1123,8 @@ void wt_status_print(struct wt_status *s)
        struct wt_status_state state;
 
        memset(&state, 0, sizeof(state));
-       wt_status_get_state(&state);
+       wt_status_get_state(&state,
+                           s->branch && !strcmp(s->branch, "HEAD"));
 
        if (s->branch) {
                const char *on_what = _("On branch ");
@@ -1062,9 +1132,19 @@ void wt_status_print(struct wt_status *s)
                if (!prefixcmp(branch_name, "refs/heads/"))
                        branch_name += 11;
                else if (!strcmp(branch_name, "HEAD")) {
-                       branch_name = "";
                        branch_status_color = color(WT_STATUS_NOBRANCH, s);
-                       on_what = _("Not currently on any branch.");
+                       if (state.detached_from) {
+                               unsigned char sha1[20];
+                               branch_name = state.detached_from;
+                               if (!get_sha1("HEAD", sha1) &&
+                                   !hashcmp(sha1, state.detached_sha1))
+                                       on_what = _("HEAD detached at ");
+                               else
+                                       on_what = _("HEAD detached from ");
+                       } else {
+                               branch_name = "";
+                               on_what = _("Not currently on any branch.");
+                       }
                }
                status_printf(s, color(WT_STATUS_HEADER, s), "");
                status_printf_more(s, branch_status_color, "%s", on_what);
@@ -1076,6 +1156,7 @@ void wt_status_print(struct wt_status *s)
        wt_status_print_state(s, &state);
        free(state.branch);
        free(state.onto);
+       free(state.detached_from);
 
        if (s->is_initial) {
                status_printf_ln(s, color(WT_STATUS_HEADER, s), "");

diff --git a/wt-status.h b/wt-status.h
index 5ddcbf6b17b5b1d1e60dc562b1fd681bddbb9fde..5cb7df91571c79bbd809943287ddbe1eb76d98ed 100644 (file)
--- a/wt-status.h
+++ b/wt-status.h
@@ -81,12 +81,14 @@ struct wt_status_state {
        int bisect_in_progress;
        char *branch;
        char *onto;
+       char *detached_from;
+       unsigned char detached_sha1[20];
 };
 
 void wt_status_prepare(struct wt_status *s);
 void wt_status_print(struct wt_status *s);
 void wt_status_collect(struct wt_status *s);
-void wt_status_get_state(struct wt_status_state *state);
+void wt_status_get_state(struct wt_status_state *state, int get_detached_from);
 
 void wt_shortstatus_print(struct wt_status *s);
 void wt_porcelain_print(struct wt_status *s);