Merge branch 'jn/branch-move-to-self'

* jn/branch-move-to-self:
  Allow checkout -B <current-branch> to update the current branch
  branch: allow a no-op "branch -M <current-branch> HEAD"

diff --git a/branch.c b/branch.c
index d91a099fdd22b9131a1d2ddaf3778b645c53eca0..a715a1174982970943ed2c4fc1c2ab4906699fdc 100644 (file)
--- a/branch.c
+++ b/branch.c
@@ -191,7 +191,8 @@ int validate_new_branchname(const char *name, struct strbuf *ref,
 
 void create_branch(const char *head,
                   const char *name, const char *start_name,
-                  int force, int reflog, enum branch_track track)
+                  int force, int reflog, int clobber_head,
+                  enum branch_track track)
 {
        struct ref_lock *lock = NULL;
        struct commit *commit;
@@ -206,7 +207,8 @@ void create_branch(const char *head,
                explicit_tracking = 1;
 
        if (validate_new_branchname(name, &ref, force,
-                                   track == BRANCH_TRACK_OVERRIDE)) {
+                                   track == BRANCH_TRACK_OVERRIDE ||
+                                   clobber_head)) {
                if (!force)
                        dont_change_ref = 1;
                else

diff --git a/branch.h b/branch.h
index 1493f73722161cc191f0c7fd655781d8b748ed41..b99c5a369e31a85d1fff822460e69a79d8c6102b 100644 (file)
--- a/branch.h
+++ b/branch.h
@@ -13,7 +13,8 @@
  * branch for (if any).
  */
 void create_branch(const char *head, const char *name, const char *start_name,
-                  int force, int reflog, enum branch_track track);
+                  int force, int reflog,
+                  int clobber_head, enum branch_track track);
 
 /*
  * Validates that the requested branch may be created, returning the

diff --git a/builtin/branch.c b/builtin/branch.c
index e1e486e4c51194e09df3779be254cb72855d1103..465ff6a513f3e314d4a526b6f8ee9f7a7c7b43f4 100644 (file)
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -570,6 +570,7 @@ static void rename_branch(const char *oldname, const char *newname, int force)
        struct strbuf oldref = STRBUF_INIT, newref = STRBUF_INIT, logmsg = STRBUF_INIT;
        struct strbuf oldsection = STRBUF_INIT, newsection = STRBUF_INIT;
        int recovery = 0;
+       int clobber_head_ok;
 
        if (!oldname)
                die(_("cannot rename the current branch while not on any."));
@@ -585,7 +586,13 @@ static void rename_branch(const char *oldname, const char *newname, int force)
                        die(_("Invalid branch name: '%s'"), oldname);
        }
 
-       validate_new_branchname(newname, &newref, force, 0);
+       /*
+        * A command like "git branch -M currentbranch currentbranch" cannot
+        * cause the worktree to become inconsistent with HEAD, so allow it.
+        */
+       clobber_head_ok = !strcmp(oldname, newname);
+
+       validate_new_branchname(newname, &newref, force, clobber_head_ok);
 
        strbuf_addf(&logmsg, "Branch: renamed %s to %s",
                 oldref.buf, newref.buf);
@@ -784,7 +791,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
                if (kinds != REF_LOCAL_BRANCH)
                        die(_("-a and -r options to 'git branch' do not make sense with a branch name"));
                create_branch(head, argv[0], (argc == 2) ? argv[1] : head,
-                             force_create, reflog, track);
+                             force_create, reflog, 0, track);
        } else
                usage_with_options(builtin_branch_usage, options);
 

diff --git a/builtin/checkout.c b/builtin/checkout.c
index b7c630287dda662630af9883655ed23bd50e7b7e..3f5d9b629a515d1531ff801fabdb9a72246d5d5c 100644 (file)
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -540,7 +540,9 @@ static void update_refs_for_switch(struct checkout_opts *opts,
                else
                        create_branch(old->name, opts->new_branch, new->name,
                                      opts->new_branch_force ? 1 : 0,
-                                     opts->new_branch_log, opts->track);
+                                     opts->new_branch_log,
+                                     opts->new_branch_force ? 1 : 0,
+                                     opts->track);
                new->name = opts->new_branch;
                setup_branch_path(new);
        }
@@ -565,8 +567,12 @@ static void update_refs_for_switch(struct checkout_opts *opts,
                create_symref("HEAD", new->path, msg.buf);
                if (!opts->quiet) {
                        if (old->path && !strcmp(new->path, old->path)) {
-                               fprintf(stderr, _("Already on '%s'\n"),
-                                       new->name);
+                               if (opts->new_branch_force)
+                                       fprintf(stderr, _("Reset branch '%s'\n"),
+                                               new->name);
+                               else
+                                       fprintf(stderr, _("Already on '%s'\n"),
+                                               new->name);
                        } else if (opts->new_branch) {
                                if (opts->branch_exists)
                                        fprintf(stderr, _("Switched to and reset branch '%s'\n"), new->name);
@@ -1059,7 +1065,8 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                struct strbuf buf = STRBUF_INIT;
 
                opts.branch_exists = validate_new_branchname(opts.new_branch, &buf,
-                                                            !!opts.new_branch_force, 0);
+                                                            !!opts.new_branch_force,
+                                                            !!opts.new_branch_force);
 
                strbuf_release(&buf);
        }

diff --git a/t/t2018-checkout-branch.sh b/t/t2018-checkout-branch.sh
index 75874e85dfbcae8ea9634693a93524841b741559..2741262369e40a05cdc6732e4c9e6f04acb63bba 100755 (executable)
--- a/t/t2018-checkout-branch.sh
+++ b/t/t2018-checkout-branch.sh
@@ -189,12 +189,13 @@ test_expect_success 'checkout -b <describe>' '
        test_cmp expect actual
 '
 
-test_expect_success 'checkout -B to the current branch fails before merging' '
+test_expect_success 'checkout -B to the current branch works' '
        git checkout branch1 &&
+       git checkout -B branch1-scratch &&
+
        setup_dirty_mergeable &&
-       git commit -mfooble &&
-       test_must_fail git checkout -B branch1 initial &&
-       test_must_fail test_dirty_mergeable
+       git checkout -B branch1-scratch initial &&
+       test_dirty_mergeable
 '
 
 test_done

diff --git a/t/t3200-branch.sh b/t/t3200-branch.sh
index bc73c2099b5069ab136a1d93aef5a8ab4a0dad1f..76903323af37ed1a96b5a11c27eb1e9d63a0e9ef 100755 (executable)
--- a/t/t3200-branch.sh
+++ b/t/t3200-branch.sh
@@ -115,6 +115,22 @@ test_expect_success 'git branch -M baz bam should succeed when baz is checked ou
        git branch -M baz bam
 '
 
+test_expect_success 'git branch -M master should work when master is checked out' '
+       git checkout master &&
+       git branch -M master
+'
+
+test_expect_success 'git branch -M master master should work when master is checked out' '
+       git checkout master &&
+       git branch -M master master
+'
+
+test_expect_success 'git branch -M master2 master2 should work when master is checked out' '
+       git checkout master &&
+       git branch master2 &&
+       git branch -M master2 master2
+'
+
 test_expect_success 'git branch -v -d t should work' '
        git branch t &&
        test_path_is_file .git/refs/heads/t &&