From 2957709bd44a5b18d180ba4c3864a431a5aaed38 Mon Sep 17 00:00:00 2001 From: Alexandr Miloslavskiy Date: Mon, 30 Dec 2019 18:38:12 +0000 Subject: [PATCH 1/2] parse_branchname_arg(): extract part as new function This is done for the next commit to avoid crazy 7x tab code padding. Signed-off-by: Alexandr Miloslavskiy Signed-off-by: Junio C Hamano --- builtin/checkout.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/builtin/checkout.c b/builtin/checkout.c index 3634a3dac15ae9..11fe4fa7e7e0e9 100644 --- a/builtin/checkout.c +++ b/builtin/checkout.c @@ -1113,6 +1113,22 @@ static void setup_new_branch_info_and_source_tree( } } +static const char *parse_remote_branch(const char *arg, + struct object_id *rev, + int could_be_checkout_paths, + int *dwim_remotes_matched) +{ + const char *remote = unique_tracking_name(arg, rev, dwim_remotes_matched); + + if (remote && could_be_checkout_paths) { + die(_("'%s' could be both a local file and a tracking branch.\n" + "Please use -- (and optionally --no-guess) to disambiguate"), + arg); + } + + return remote; +} + static int parse_branchname_arg(int argc, const char **argv, int dwim_new_local_branch_ok, struct branch_info *new_branch_info, @@ -1223,13 +1239,10 @@ static int parse_branchname_arg(int argc, const char **argv, recover_with_dwim = 0; if (recover_with_dwim) { - const char *remote = unique_tracking_name(arg, rev, - dwim_remotes_matched); + const char *remote = parse_remote_branch(arg, rev, + could_be_checkout_paths, + dwim_remotes_matched); if (remote) { - if (could_be_checkout_paths) - die(_("'%s' could be both a local file and a tracking branch.\n" - "Please use -- (and optionally --no-guess) to disambiguate"), - arg); *new_branch = arg; arg = remote; /* DWIMmed to create local branch, case (3).(b) */ From fa74180d08e0a82bdae0c127a009b055c603b11a Mon Sep 17 00:00:00 2001 From: Alexandr Miloslavskiy Date: Mon, 30 Dec 2019 18:38:13 +0000 Subject: [PATCH 2/2] checkout: don't revert file on ambiguous tracking branches For easier understanding, here are the existing good scenarios: 1) Have *no* file 'foo', *no* local branch 'foo' and a *single* remote branch 'foo' 2) `git checkout foo` will create local branch foo, see [1] and 1) Have *a* file 'foo', *no* local branch 'foo' and a *single* remote branch 'foo' 2) `git checkout foo` will complain, see [3] This patch prevents the following scenario: 1) Have *a* file 'foo', *no* local branch 'foo' and *multiple* remote branches 'foo' 2) `git checkout foo` will successfully... revert contents of file `foo`! That is, adding another remote suddenly changes behavior significantly, which is a surprise at best and could go unnoticed by user at worst. Please see [3] which gives some real world complaints. To my understanding, fix in [3] overlooked the case of multiple remotes, and the whole behavior of falling back to reverting file was never intended: [1] introduces the unexpected behavior. Before, there was fallback from not-a-ref to pathspec. This is reasonable fallback. After, there is another fallback from ambiguous-remote to pathspec. I understand that it was a copy&paste oversight. [2] noticed the unexpected behavior but chose to semi-document it instead of forbidding, because the goal of the patch series was focused on something else. [3] adds `die()` when there is ambiguity between branch and file. The case of multiple tracking branches is seemingly overlooked. The new behavior: if there is no local branch and multiple remote candidates, just die() and don't try reverting file whether it exists (prevents surprise) or not (improves error message). [1] Commit 70c9ac2f ("DWIM "git checkout frotz" to "git checkout -b frotz origin/frotz"" 2009-10-18) https://public-inbox.org/git/7vaazpxha4.fsf_-_@alter.siamese.dyndns.org/ [2] Commit ad8d5104 ("checkout: add advice for ambiguous "checkout "", 2018-06-05) https://public-inbox.org/git/20180502105452.17583-1-avarab@gmail.com/ [3] Commit be4908f1 ("checkout: disambiguate dwim tracking branches and local files", 2018-11-13) https://public-inbox.org/git/20181110120707.25846-1-pclouds@gmail.com/ Signed-off-by: Alexandr Miloslavskiy Signed-off-by: Junio C Hamano --- builtin/checkout.c | 56 ++++++++++++++++++---------------------- t/t2024-checkout-dwim.sh | 28 ++++++++++++++++++-- 2 files changed, 51 insertions(+), 33 deletions(-) diff --git a/builtin/checkout.c b/builtin/checkout.c index 11fe4fa7e7e0e9..01c6790dab0a1d 100644 --- a/builtin/checkout.c +++ b/builtin/checkout.c @@ -1115,10 +1115,10 @@ static void setup_new_branch_info_and_source_tree( static const char *parse_remote_branch(const char *arg, struct object_id *rev, - int could_be_checkout_paths, - int *dwim_remotes_matched) + int could_be_checkout_paths) { - const char *remote = unique_tracking_name(arg, rev, dwim_remotes_matched); + int num_matches = 0; + const char *remote = unique_tracking_name(arg, rev, &num_matches); if (remote && could_be_checkout_paths) { die(_("'%s' could be both a local file and a tracking branch.\n" @@ -1126,6 +1126,22 @@ static const char *parse_remote_branch(const char *arg, arg); } + if (!remote && num_matches > 1) { + if (advice_checkout_ambiguous_remote_branch_name) { + advise(_("If you meant to check out a remote tracking branch on, e.g. 'origin',\n" + "you can do so by fully qualifying the name with the --track option:\n" + "\n" + " git checkout --track origin/\n" + "\n" + "If you'd like to always have checkouts of an ambiguous prefer\n" + "one remote, e.g. the 'origin' remote, consider setting\n" + "checkout.defaultRemote=origin in your config.")); + } + + die(_("'%s' matched multiple (%d) remote tracking branches"), + arg, num_matches); + } + return remote; } @@ -1133,8 +1149,7 @@ static int parse_branchname_arg(int argc, const char **argv, int dwim_new_local_branch_ok, struct branch_info *new_branch_info, struct checkout_opts *opts, - struct object_id *rev, - int *dwim_remotes_matched) + struct object_id *rev) { const char **new_branch = &opts->new_branch; int argcount = 0; @@ -1240,8 +1255,7 @@ static int parse_branchname_arg(int argc, const char **argv, if (recover_with_dwim) { const char *remote = parse_remote_branch(arg, rev, - could_be_checkout_paths, - dwim_remotes_matched); + could_be_checkout_paths); if (remote) { *new_branch = arg; arg = remote; @@ -1505,7 +1519,6 @@ static int checkout_main(int argc, const char **argv, const char *prefix, const char * const usagestr[]) { struct branch_info new_branch_info; - int dwim_remotes_matched = 0; int parseopt_flags = 0; memset(&new_branch_info, 0, sizeof(new_branch_info)); @@ -1613,8 +1626,7 @@ static int checkout_main(int argc, const char **argv, const char *prefix, opts->track == BRANCH_TRACK_UNSPECIFIED && !opts->new_branch; int n = parse_branchname_arg(argc, argv, dwim_ok, - &new_branch_info, opts, &rev, - &dwim_remotes_matched); + &new_branch_info, opts, &rev); argv += n; argc -= n; } else if (!opts->accept_ref && opts->from_treeish) { @@ -1672,28 +1684,10 @@ static int checkout_main(int argc, const char **argv, const char *prefix, } UNLEAK(opts); - if (opts->patch_mode || opts->pathspec.nr) { - int ret = checkout_paths(opts, new_branch_info.name); - if (ret && dwim_remotes_matched > 1 && - advice_checkout_ambiguous_remote_branch_name) - advise(_("'%s' matched more than one remote tracking branch.\n" - "We found %d remotes with a reference that matched. So we fell back\n" - "on trying to resolve the argument as a path, but failed there too!\n" - "\n" - "If you meant to check out a remote tracking branch on, e.g. 'origin',\n" - "you can do so by fully qualifying the name with the --track option:\n" - "\n" - " git checkout --track origin/\n" - "\n" - "If you'd like to always have checkouts of an ambiguous prefer\n" - "one remote, e.g. the 'origin' remote, consider setting\n" - "checkout.defaultRemote=origin in your config."), - argv[0], - dwim_remotes_matched); - return ret; - } else { + if (opts->patch_mode || opts->pathspec.nr) + return checkout_paths(opts, new_branch_info.name); + else return checkout_branch(opts, &new_branch_info); - } } int cmd_checkout(int argc, const char **argv, const char *prefix) diff --git a/t/t2024-checkout-dwim.sh b/t/t2024-checkout-dwim.sh index fa0718c730c322..accfa9aa4bd82a 100755 --- a/t/t2024-checkout-dwim.sh +++ b/t/t2024-checkout-dwim.sh @@ -37,7 +37,9 @@ test_expect_success 'setup' ' git checkout -b foo && test_commit a_foo && git checkout -b bar && - test_commit a_bar + test_commit a_bar && + git checkout -b ambiguous_branch_and_file && + test_commit a_ambiguous_branch_and_file ) && git init repo_b && ( @@ -46,7 +48,9 @@ test_expect_success 'setup' ' git checkout -b foo && test_commit b_foo && git checkout -b baz && - test_commit b_baz + test_commit b_baz && + git checkout -b ambiguous_branch_and_file && + test_commit b_ambiguous_branch_and_file ) && git remote add repo_a repo_a && git remote add repo_b repo_b && @@ -75,6 +79,26 @@ test_expect_success 'checkout of branch from multiple remotes fails #1' ' test_branch master ' +test_expect_success 'when arg matches multiple remotes, do not fallback to interpreting as pathspec' ' + # create a file with name matching remote branch name + git checkout -b t_ambiguous_branch_and_file && + >ambiguous_branch_and_file && + git add ambiguous_branch_and_file && + git commit -m "ambiguous_branch_and_file" && + + # modify file to verify that it will not be touched by checkout + test_when_finished "git checkout -- ambiguous_branch_and_file" && + echo "file contents" >ambiguous_branch_and_file && + cp ambiguous_branch_and_file expect && + + test_must_fail git checkout ambiguous_branch_and_file 2>err && + + test_i18ngrep "matched multiple (2) remote tracking branches" err && + + # file must not be altered + test_cmp expect ambiguous_branch_and_file +' + test_expect_success 'checkout of branch from multiple remotes fails with advice' ' git checkout -B master && test_might_fail git branch -D foo &&