From: Harald Nordgren via GitGitGadget Date: Sat, 25 Apr 2026 18:12:35 GMT Subject: [PATCH v2] checkout: add --fetch to fetch remote before resolving start-point Message-ID: In-Reply-To: From: Harald Nordgren A common workflow is: git fetch origin git checkout -b new_branch origin/some-branch The first command exists purely so the second sees an up-to-date view of the remote. If it is forgotten, origin/some-branch points at a stale commit and the new local branch is created from the wrong start point. Teach checkout (and switch) a --fetch flag that folds the two steps into one: git checkout --fetch -b new_branch origin/some-branch When --fetch is given and names a configured remote (either bare, like "origin", or prefixed, like "origin/foo"), fetch that remote before resolving the ref. Abort the checkout if the fetch fails. Also add a checkout.fetch config to enable this by default. Signed-off-by: Harald Nordgren --- checkout: add --fetch to fetch remote before resolving start-point * Rename the config from checkout.autoFetch to checkout.fetch, so it matches the --fetch option name. * Rename the internal struct field from auto_fetch to fetch for consistency with the option and config names. * Reword the commit message to lead with the problem (forgetting 'git fetch' and ending up with a stale start-point) before describing the solution. * Document --fetch / --no-fetch in git-checkout and git-switch, and document checkout.fetch in the config reference. * Use "remote-tracking branch" instead of "remote-tracking ref" in the option help text. Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2281%2FHaraldNordgren%2Fcheckout-fetch-start-point-v2 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2281/HaraldNordgren/checkout-fetch-start-point-v2 Pull-Request: https://github.com/git/git/pull/2281 Range-diff vs v1: 1: e2fa50ff40 ! 1: 13074c9fea checkout: add --fetch to fetch remote before resolving start-point @@ Metadata ## Commit message ## checkout: add --fetch to fetch remote before resolving start-point - Add a --fetch option to git checkout and git switch, plus a - checkout.autoFetch config to enable it by default. When set and the - start-point argument names a configured remote (either bare, like - "origin", or prefixed, like "origin/foo"), fetch that remote before - resolving the ref. Aborts the checkout if the fetch fails. + A common workflow is: + + git fetch origin + git checkout -b new_branch origin/some-branch + + The first command exists purely so the second sees an up-to-date view + of the remote. If it is forgotten, origin/some-branch points at a stale + commit and the new local branch is created from the wrong start point. + + Teach checkout (and switch) a --fetch flag that folds the two steps + into one: + + git checkout --fetch -b new_branch origin/some-branch + + When --fetch is given and names a configured remote + (either bare, like "origin", or prefixed, like "origin/foo"), fetch + that remote before resolving the ref. Abort the checkout if the fetch + fails. + + Also add a checkout.fetch config to enable this by default. Signed-off-by: Harald Nordgren + ## Documentation/config/checkout.adoc ## +@@ Documentation/config/checkout.adoc: commands or functionality in the future. + option in `git checkout` and `git switch`. See + linkgit:git-switch[1] and linkgit:git-checkout[1]. + ++`checkout.fetch`:: ++ Provides the default value for the `--fetch` or `--no-fetch` ++ option in `git checkout` and `git switch`. See ++ linkgit:git-switch[1] and linkgit:git-checkout[1]. ++ + `checkout.workers`:: + The number of parallel workers to use when updating the working tree. + The default is one, i.e. sequential execution. If set to a value less + + ## Documentation/git-checkout.adoc ## +@@ Documentation/git-checkout.adoc: linkgit:git-config[1]. + The default behavior can be set via the `checkout.guess` configuration + variable. + ++`--fetch`:: ++`--no-fetch`:: ++ If __ names a configured remote -- either bare, ++ like `origin` (which resolves to the remote's default branch), ++ or in _/_ form -- run `git fetch` on that ++ remote before resolving __. If the fetch fails, ++ the checkout is aborted and no local branch is created. +++ ++The default behavior can be set via the `checkout.fetch` configuration ++variable. ++ + `-l`:: + Create the new branch's reflog; see linkgit:git-branch[1] for + details. + + ## Documentation/git-switch.adoc ## +@@ Documentation/git-switch.adoc: ambiguous but exists on the 'origin' remote. See also + The default behavior can be set via the `checkout.guess` configuration + variable. + ++`--fetch`:: ++`--no-fetch`:: ++ If __ names a configured remote -- either bare, ++ like `origin` (which resolves to the remote's default branch), ++ or in _/_ form -- run `git fetch` on that ++ remote before resolving __. If the fetch fails, ++ the switch is aborted and no local branch is created. +++ ++The default behavior can be set via the `checkout.fetch` configuration ++variable. ++ + `-f`:: + `--force`:: + An alias for `--discard-changes`. + ## builtin/checkout.c ## @@ #include "repo-settings.h" @@ builtin/checkout.c: struct checkout_opts { int count_checkout_paths; int overlay_mode; int dwim_new_local_branch; -+ int auto_fetch; ++ int fetch; int discard_changes; int accept_ref; int accept_pathspec; @@ builtin/checkout.c: static int git_checkout_config(const char *var, const char * opts->dwim_new_local_branch = git_config_bool(var, value); return 0; } -+ if (!strcmp(var, "checkout.autofetch")) { -+ opts->auto_fetch = git_config_bool(var, value); ++ if (!strcmp(var, "checkout.fetch")) { ++ opts->fetch = git_config_bool(var, value); + return 0; + } @@ builtin/checkout.c: static int checkout_main(int argc, const char **argv, const - &new_branch_info, opts, &rev); + int n; + -+ if (opts->auto_fetch) ++ if (opts->fetch) + fetch_remote_for_start_point(argv[0]); + + n = parse_branchname_arg(argc, argv, dwim_ok, which_command, @@ builtin/checkout.c: int cmd_checkout(int argc, OPT_BOOL(0, "overlay", &opts.overlay_mode, N_("use overlay mode (default)")), OPT_BOOL(0, "auto-advance", &opts.auto_advance, N_("auto advance to the next file when selecting hunks interactively")), -+ OPT_BOOL(0, "fetch", &opts.auto_fetch, -+ N_("fetch from the remote first if is a remote-tracking ref")), ++ OPT_BOOL(0, "fetch", &opts.fetch, ++ N_("fetch from the remote first if is a remote-tracking branch")), OPT_END() }; @@ builtin/checkout.c: int cmd_switch(int argc, N_("second guess 'git switch '")), OPT_BOOL(0, "discard-changes", &opts.discard_changes, N_("throw away local modifications")), -+ OPT_BOOL(0, "fetch", &opts.auto_fetch, -+ N_("fetch from the remote first if is a remote-tracking ref")), ++ OPT_BOOL(0, "fetch", &opts.fetch, ++ N_("fetch from the remote first if is a remote-tracking branch")), OPT_END() }; @@ t/t7201-co.sh: test_expect_success 'tracking info copied with autoSetupMerge=inh + test_must_fail git rev-parse --verify refs/heads/bogus +' + -+test_expect_success 'checkout.autoFetch=true enables fetching without --fetch' ' ++test_expect_success 'checkout.fetch=true enables fetching without --fetch' ' + git checkout main && + git -C fetch_upstream checkout -b fetch_cfg && + test_commit -C fetch_upstream u_cfg && + test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_cfg && -+ git -c checkout.autoFetch=true checkout -b local_cfg fetch_upstream/fetch_cfg && ++ git -c checkout.fetch=true checkout -b local_cfg fetch_upstream/fetch_cfg && + test_cmp_rev refs/remotes/fetch_upstream/fetch_cfg HEAD +' + Documentation/config/checkout.adoc | 5 +++ Documentation/git-checkout.adoc | 11 +++++++ Documentation/git-switch.adoc | 11 +++++++ builtin/checkout.c | 48 ++++++++++++++++++++++++++-- t/t7201-co.sh | 51 ++++++++++++++++++++++++++++++ t/t9902-completion.sh | 1 + 6 files changed, 125 insertions(+), 2 deletions(-) diff --git a/Documentation/config/checkout.adoc b/Documentation/config/checkout.adoc index e35d212969..c95f72b38e 100644 --- a/Documentation/config/checkout.adoc +++ b/Documentation/config/checkout.adoc @@ -22,6 +22,11 @@ commands or functionality in the future. option in `git checkout` and `git switch`. See linkgit:git-switch[1] and linkgit:git-checkout[1]. +`checkout.fetch`:: + Provides the default value for the `--fetch` or `--no-fetch` + option in `git checkout` and `git switch`. See + linkgit:git-switch[1] and linkgit:git-checkout[1]. + `checkout.workers`:: The number of parallel workers to use when updating the working tree. The default is one, i.e. sequential execution. If set to a value less diff --git a/Documentation/git-checkout.adoc b/Documentation/git-checkout.adoc index 43ccf47cf6..f20e2f4c8c 100644 --- a/Documentation/git-checkout.adoc +++ b/Documentation/git-checkout.adoc @@ -201,6 +201,17 @@ linkgit:git-config[1]. The default behavior can be set via the `checkout.guess` configuration variable. +`--fetch`:: +`--no-fetch`:: + If __ names a configured remote -- either bare, + like `origin` (which resolves to the remote's default branch), + or in _/_ form -- run `git fetch` on that + remote before resolving __. If the fetch fails, + the checkout is aborted and no local branch is created. ++ +The default behavior can be set via the `checkout.fetch` configuration +variable. + `-l`:: Create the new branch's reflog; see linkgit:git-branch[1] for details. diff --git a/Documentation/git-switch.adoc b/Documentation/git-switch.adoc index 87707e9265..3826ed9066 100644 --- a/Documentation/git-switch.adoc +++ b/Documentation/git-switch.adoc @@ -110,6 +110,17 @@ ambiguous but exists on the 'origin' remote. See also The default behavior can be set via the `checkout.guess` configuration variable. +`--fetch`:: +`--no-fetch`:: + If __ names a configured remote -- either bare, + like `origin` (which resolves to the remote's default branch), + or in _/_ form -- run `git fetch` on that + remote before resolving __. If the fetch fails, + the switch is aborted and no local branch is created. ++ +The default behavior can be set via the `checkout.fetch` configuration +variable. + `-f`:: `--force`:: An alias for `--discard-changes`. diff --git a/builtin/checkout.c b/builtin/checkout.c index e031e61886..b2a34f0f00 100644 --- a/builtin/checkout.c +++ b/builtin/checkout.c @@ -30,7 +30,9 @@ #include "repo-settings.h" #include "resolve-undo.h" #include "revision.h" +#include "run-command.h" #include "setup.h" +#include "strvec.h" #include "submodule.h" #include "symlinks.h" #include "trace2.h" @@ -61,6 +63,7 @@ struct checkout_opts { int count_checkout_paths; int overlay_mode; int dwim_new_local_branch; + int fetch; int discard_changes; int accept_ref; int accept_pathspec; @@ -112,6 +115,34 @@ struct branch_info { char *checkout; }; +static void fetch_remote_for_start_point(const char *arg) +{ + const char *slash; + char *remote_name; + struct remote *remote; + struct child_process cmd = CHILD_PROCESS_INIT; + + if (!arg || !*arg) + return; + + slash = strchr(arg, '/'); + if (slash == arg) + return; + remote_name = slash ? xstrndup(arg, slash - arg) : xstrdup(arg); + + remote = remote_get(remote_name); + if (!remote || !remote_is_configured(remote, 1)) { + free(remote_name); + return; + } + + strvec_pushl(&cmd.args, "fetch", remote_name, NULL); + cmd.git_cmd = 1; + free(remote_name); + if (run_command(&cmd)) + die(_("failed to fetch start-point '%s'"), arg); +} + static void branch_info_release(struct branch_info *info) { free(info->name); @@ -1237,6 +1268,10 @@ static int git_checkout_config(const char *var, const char *value, opts->dwim_new_local_branch = git_config_bool(var, value); return 0; } + if (!strcmp(var, "checkout.fetch")) { + opts->fetch = git_config_bool(var, value); + return 0; + } if (starts_with(var, "submodule.")) return git_default_submodule_config(var, value, NULL); @@ -1942,8 +1977,13 @@ static int checkout_main(int argc, const char **argv, const char *prefix, opts->dwim_new_local_branch && opts->track == BRANCH_TRACK_UNSPECIFIED && !opts->new_branch; - int n = parse_branchname_arg(argc, argv, dwim_ok, which_command, - &new_branch_info, opts, &rev); + int n; + + if (opts->fetch) + fetch_remote_for_start_point(argv[0]); + + n = parse_branchname_arg(argc, argv, dwim_ok, which_command, + &new_branch_info, opts, &rev); argv += n; argc -= n; } else if (!opts->accept_ref && opts->from_treeish) { @@ -2052,6 +2092,8 @@ int cmd_checkout(int argc, OPT_BOOL(0, "overlay", &opts.overlay_mode, N_("use overlay mode (default)")), OPT_BOOL(0, "auto-advance", &opts.auto_advance, N_("auto advance to the next file when selecting hunks interactively")), + OPT_BOOL(0, "fetch", &opts.fetch, + N_("fetch from the remote first if is a remote-tracking branch")), OPT_END() }; @@ -2102,6 +2144,8 @@ int cmd_switch(int argc, N_("second guess 'git switch '")), OPT_BOOL(0, "discard-changes", &opts.discard_changes, N_("throw away local modifications")), + OPT_BOOL(0, "fetch", &opts.fetch, + N_("fetch from the remote first if is a remote-tracking branch")), OPT_END() }; diff --git a/t/t7201-co.sh b/t/t7201-co.sh index 9bcf7c0b40..f5729f0831 100755 --- a/t/t7201-co.sh +++ b/t/t7201-co.sh @@ -801,4 +801,55 @@ test_expect_success 'tracking info copied with autoSetupMerge=inherit' ' test_cmp_config "" --default "" branch.main2.merge ' +test_expect_success 'setup upstream for --fetch tests' ' + git checkout main && + git init fetch_upstream && + test_commit -C fetch_upstream u_main && + git remote add fetch_upstream fetch_upstream && + git fetch fetch_upstream && + git -C fetch_upstream checkout -b fetch_new && + test_commit -C fetch_upstream u_new +' + +test_expect_success 'checkout --fetch -b picks up branch created upstream after clone' ' + git checkout main && + test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_new && + git checkout --fetch -b local_new fetch_upstream/fetch_new && + test_cmp_rev refs/remotes/fetch_upstream/fetch_new HEAD +' + +test_expect_success 'checkout --fetch with bare remote name fetches the remote' ' + git checkout main && + git -C fetch_upstream checkout -b fetch_new2 && + test_commit -C fetch_upstream u_new2 && + test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_new2 && + git checkout --fetch -b local_from_remote fetch_upstream && + git rev-parse --verify refs/remotes/fetch_upstream/fetch_new2 +' + +test_expect_success 'checkout --fetch aborts and does not create branch on fetch failure' ' + git checkout main && + test_might_fail git branch -D bogus && + test_must_fail git checkout --fetch -b bogus fetch_upstream/does_not_exist && + test_must_fail git rev-parse --verify refs/heads/bogus +' + +test_expect_success 'checkout.fetch=true enables fetching without --fetch' ' + git checkout main && + git -C fetch_upstream checkout -b fetch_cfg && + test_commit -C fetch_upstream u_cfg && + test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_cfg && + git -c checkout.fetch=true checkout -b local_cfg fetch_upstream/fetch_cfg && + test_cmp_rev refs/remotes/fetch_upstream/fetch_cfg HEAD +' + +test_expect_success 'switch --fetch -c picks up branch created upstream after clone' ' + git checkout main && + git -C fetch_upstream checkout -b fetch_switch && + test_commit -C fetch_upstream u_switch && + test_must_fail git rev-parse --verify refs/remotes/fetch_upstream/fetch_switch && + git switch --fetch -c local_switch fetch_upstream/fetch_switch && + test_cmp_rev refs/remotes/fetch_upstream/fetch_switch HEAD +' + test_done diff --git a/t/t9902-completion.sh b/t/t9902-completion.sh index 2f9a597ec7..dc1d63669f 100755 --- a/t/t9902-completion.sh +++ b/t/t9902-completion.sh @@ -2602,6 +2602,7 @@ test_expect_success 'double dash "git checkout"' ' --ignore-other-worktrees Z --recurse-submodules Z --auto-advance Z + --fetch Z --progress Z --guess Z --no-guess Z base-commit: 94f057755b7941b321fd11fec1b2e3ca5313a4e0 -- gitgitgadget