From 529fef20cf94dbd5c16f7a239ffc2b06f3cf8bb7 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?= Date: Sun, 30 Nov 2014 15:24:47 +0700 Subject: [PATCH] checkout: support checking out into a new working directory MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit "git checkout --to" sets up a new working directory with a .git file pointing to $GIT_DIR/worktrees/. It then executes "git checkout" again on the new worktree with the same arguments except "--to" is taken out. The second checkout execution, which is not contaminated with any info from the current repository, will actually check out and everything that normal "git checkout" does. Helped-by: Marc Branchaud Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano --- Documentation/git-checkout.txt | 46 ++++++++++++++++ Documentation/git.txt | 3 +- Documentation/gitrepository-layout.txt | 7 +++ builtin/checkout.c | 95 +++++++++++++++++++++++++++++++++- path.c | 2 +- t/t2025-checkout-to.sh | 63 ++++++++++++++++++++++ 6 files changed, 212 insertions(+), 4 deletions(-) create mode 100755 t/t2025-checkout-to.sh diff --git a/Documentation/git-checkout.txt b/Documentation/git-checkout.txt index 33ad2adf5c..c101575ac2 100644 --- a/Documentation/git-checkout.txt +++ b/Documentation/git-checkout.txt @@ -225,6 +225,13 @@ This means that you can use `git checkout -p` to selectively discard edits from your current working tree. See the ``Interactive Mode'' section of linkgit:git-add[1] to learn how to operate the `--patch` mode. +--to=:: + Check out a branch in a separate working directory at + ``. A new working directory is linked to the current + repository, sharing everything except working directory + specific files such as HEAD, index... See "MULTIPLE WORKING + TREES" section for more information. + :: Branch to checkout; if it refers to a branch (i.e., a name that, when prepended with "refs/heads/", is a valid ref), then that @@ -388,6 +395,45 @@ $ git reflog -2 HEAD # or $ git log -g -2 HEAD ------------ +MULTIPLE WORKING TREES +---------------------- + +A git repository can support multiple working trees, allowing you to check +out more than one branch at a time. With `git checkout --to` a new working +tree is associated with the repository. This new working tree is called a +"linked working tree" as opposed to the "main working tree" prepared by "git +init" or "git clone". A repository has one main working tree (if it's not a +bare repository) and zero or more linked working trees. + +Each linked working tree has a private sub-directory in the repository's +$GIT_DIR/worktrees directory. The private sub-directory's name is usually +the base name of the linked working tree's path, possibly appended with a +number to make it unique. For example, when `$GIT_DIR=/path/main/.git` the +command `git checkout --to /path/other/test-next next` creates the linked +working tree in `/path/other/test-next` and also creates a +`$GIT_DIR/worktrees/test-next` directory (or `$GIT_DIR/worktrees/test-next1` +if `test-next` is already taken). + +Within a linked working tree, $GIT_DIR is set to point to this private +directory (e.g. `/path/main/.git/worktrees/test-next` in the example) and +$GIT_COMMON_DIR is set to point back to the main working tree's $GIT_DIR +(e.g. `/path/main/.git`). These settings are made in a `.git` file located at +the top directory of the linked working tree. + +Path resolution via `git rev-parse --git-path` uses either +$GIT_DIR or $GIT_COMMON_DIR depending on the path. For example, in the +linked working tree `git rev-parse --git-path HEAD` returns +`/path/main/.git/worktrees/test-next/HEAD` (not +`/path/other/test-next/.git/HEAD` or `/path/main/.git/HEAD`) while `git +rev-parse --git-path refs/heads/master` uses +$GIT_COMMON_DIR and returns `/path/main/.git/refs/heads/master`, +since refs are shared across all working trees. + +See linkgit:gitrepository-layout[5] for more information. The rule of +thumb is do not make any assumption about whether a path belongs to +$GIT_DIR or $GIT_COMMON_DIR when you need to directly access something +inside $GIT_DIR. Use `git rev-parse --git-path` to get the final path. + EXAMPLES -------- diff --git a/Documentation/git.txt b/Documentation/git.txt index 96354af0d7..0c2dcfa9cc 100644 --- a/Documentation/git.txt +++ b/Documentation/git.txt @@ -813,7 +813,8 @@ Git so take care if using Cogito etc. If this variable is set to a path, non-worktree files that are normally in $GIT_DIR will be taken from this path instead. Worktree-specific files such as HEAD or index are - taken from $GIT_DIR. See linkgit:gitrepository-layout[5] for + taken from $GIT_DIR. See linkgit:gitrepository-layout[5] and + the section 'MULTIPLE CHECKOUT MODE' in linkgit:checkout[1] details. This variable has lower precedence than other path variables such as GIT_INDEX_FILE, GIT_OBJECT_DIRECTORY... diff --git a/Documentation/gitrepository-layout.txt b/Documentation/gitrepository-layout.txt index 2dc5667a0c..82284506a4 100644 --- a/Documentation/gitrepository-layout.txt +++ b/Documentation/gitrepository-layout.txt @@ -252,6 +252,13 @@ modules:: directory is ignored if $GIT_COMMON_DIR is set and "$GIT_COMMON_DIR/modules" will be used instead. +worktrees:: + Contains worktree specific information of linked + checkouts. Each subdirectory contains the worktree-related + part of a linked checkout. This directory is ignored if + $GIT_COMMON_DIR is set and "$GIT_COMMON_DIR/worktrees" will be + used instead. + SEE ALSO -------- linkgit:git-init[1], diff --git a/builtin/checkout.c b/builtin/checkout.c index 195aca7257..797e14df41 100644 --- a/builtin/checkout.c +++ b/builtin/checkout.c @@ -48,6 +48,10 @@ struct checkout_opts { const char *prefix; struct pathspec pathspec; struct tree *source_tree; + + const char *new_worktree; + const char **saved_argv; + int new_worktree_mode; }; static int post_checkout_hook(struct commit *old, struct commit *new, @@ -249,6 +253,9 @@ static int checkout_paths(const struct checkout_opts *opts, die(_("Cannot update paths and switch to branch '%s' at the same time."), opts->new_branch); + if (opts->new_worktree) + die(_("'%s' cannot be used with updating paths"), "--to"); + if (opts->patch_mode) return run_add_interactive(revision, "--patch=checkout", &opts->pathspec); @@ -484,7 +491,7 @@ static int merge_working_tree(const struct checkout_opts *opts, topts.dir->flags |= DIR_SHOW_IGNORED; setup_standard_excludes(topts.dir); } - tree = parse_tree_indirect(old->commit ? + tree = parse_tree_indirect(old->commit && !opts->new_worktree_mode ? old->commit->object.sha1 : EMPTY_TREE_SHA1_BIN); init_tree_desc(&trees[0], tree->buffer, tree->size); @@ -800,7 +807,8 @@ static int switch_branches(const struct checkout_opts *opts, return ret; } - if (!opts->quiet && !old.path && old.commit && new->commit != old.commit) + if (!opts->quiet && !old.path && old.commit && + new->commit != old.commit && !opts->new_worktree_mode) orphaned_commit_warning(old.commit, new->commit); update_refs_for_switch(opts, &old, new); @@ -810,6 +818,76 @@ static int switch_branches(const struct checkout_opts *opts, return ret || writeout_error; } +static int prepare_linked_checkout(const struct checkout_opts *opts, + struct branch_info *new) +{ + struct strbuf sb_git = STRBUF_INIT, sb_repo = STRBUF_INIT; + struct strbuf sb = STRBUF_INIT; + const char *path = opts->new_worktree, *name; + struct stat st; + struct child_process cp; + int counter = 0, len; + + if (!new->commit) + die(_("no branch specified")); + if (file_exists(path)) + die(_("'%s' already exists"), path); + + len = strlen(path); + while (len && is_dir_sep(path[len - 1])) + len--; + + for (name = path + len - 1; name > path; name--) + if (is_dir_sep(*name)) { + name++; + break; + } + strbuf_addstr(&sb_repo, + git_path("worktrees/%.*s", (int)(path + len - name), name)); + len = sb_repo.len; + if (safe_create_leading_directories_const(sb_repo.buf)) + die_errno(_("could not create leading directories of '%s'"), + sb_repo.buf); + while (!stat(sb_repo.buf, &st)) { + counter++; + strbuf_setlen(&sb_repo, len); + strbuf_addf(&sb_repo, "%d", counter); + } + name = strrchr(sb_repo.buf, '/') + 1; + if (mkdir(sb_repo.buf, 0777)) + die_errno(_("could not create directory of '%s'"), sb_repo.buf); + + strbuf_addf(&sb_git, "%s/.git", path); + if (safe_create_leading_directories_const(sb_git.buf)) + die_errno(_("could not create leading directories of '%s'"), + sb_git.buf); + + write_file(sb_git.buf, 1, "gitdir: %s/worktrees/%s\n", + real_path(get_git_common_dir()), name); + /* + * This is to keep resolve_ref() happy. We need a valid HEAD + * or is_git_directory() will reject the directory. Any valid + * value would do because this value will be ignored and + * replaced at the next (real) checkout. + */ + strbuf_addf(&sb, "%s/HEAD", sb_repo.buf); + write_file(sb.buf, 1, "%s\n", sha1_to_hex(new->commit->object.sha1)); + strbuf_reset(&sb); + strbuf_addf(&sb, "%s/commondir", sb_repo.buf); + write_file(sb.buf, 1, "../..\n"); + + if (!opts->quiet) + fprintf_ln(stderr, _("Enter %s (identifier %s)"), path, name); + + setenv("GIT_CHECKOUT_NEW_WORKTREE", "1", 1); + setenv(GIT_DIR_ENVIRONMENT, sb_git.buf, 1); + setenv(GIT_WORK_TREE_ENVIRONMENT, path, 1); + memset(&cp, 0, sizeof(cp)); + cp.git_cmd = 1; + cp.argv = opts->saved_argv; + return run_command(&cp); +} + static int git_checkout_config(const char *var, const char *value, void *cb) { if (!strcmp(var, "diff.ignoresubmodules")) { @@ -1071,6 +1149,9 @@ static int checkout_branch(struct checkout_opts *opts, die(_("Cannot switch branch to a non-commit '%s'"), new->name); + if (opts->new_worktree) + return prepare_linked_checkout(opts, new); + if (!new->commit && opts->new_branch) { unsigned char rev[20]; int flag; @@ -1113,6 +1194,8 @@ int cmd_checkout(int argc, const char **argv, const char *prefix) N_("do not limit pathspecs to sparse entries only")), OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch, N_("second guess 'git checkout no-such-branch'")), + OPT_FILENAME(0, "to", &opts.new_worktree, + N_("check a branch out in a separate working directory")), OPT_END(), }; @@ -1121,6 +1204,9 @@ int cmd_checkout(int argc, const char **argv, const char *prefix) opts.overwrite_ignore = 1; opts.prefix = prefix; + opts.saved_argv = xmalloc(sizeof(const char *) * (argc + 2)); + memcpy(opts.saved_argv, argv, sizeof(const char *) * (argc + 1)); + gitmodules_config(); git_config(git_checkout_config, &opts); @@ -1129,6 +1215,11 @@ int cmd_checkout(int argc, const char **argv, const char *prefix) argc = parse_options(argc, argv, prefix, options, checkout_usage, PARSE_OPT_KEEP_DASHDASH); + /* recursive execution from checkout_new_worktree() */ + opts.new_worktree_mode = getenv("GIT_CHECKOUT_NEW_WORKTREE") != NULL; + if (opts.new_worktree_mode) + opts.new_worktree = NULL; + if (conflict_style) { opts.merge = 1; /* implied */ git_xmerge_config("merge.conflictstyle", conflict_style, NULL); diff --git a/path.c b/path.c index 94db5016c4..72eca6dfa5 100644 --- a/path.c +++ b/path.c @@ -92,7 +92,7 @@ static void replace_dir(struct strbuf *buf, int len, const char *newdir) static const char *common_list[] = { "/branches", "/hooks", "/info", "/logs", "/lost-found", "/modules", - "/objects", "/refs", "/remotes", "/rr-cache", "/svn", + "/objects", "/refs", "/remotes", "/worktrees", "/rr-cache", "/svn", "config", "gc.pid", "packed-refs", "shallow", NULL }; diff --git a/t/t2025-checkout-to.sh b/t/t2025-checkout-to.sh new file mode 100755 index 0000000000..49634157bf --- /dev/null +++ b/t/t2025-checkout-to.sh @@ -0,0 +1,63 @@ +#!/bin/sh + +test_description='test git checkout --to' + +. ./test-lib.sh + +test_expect_success 'setup' ' + test_commit init +' + +test_expect_success 'checkout --to not updating paths' ' + test_must_fail git checkout --to -- init.t +' + +test_expect_success 'checkout --to an existing worktree' ' + mkdir existing && + test_must_fail git checkout --detach --to existing master +' + +test_expect_success 'checkout --to a new worktree' ' + git checkout --to here master && + ( + cd here && + test_cmp ../init.t init.t && + git symbolic-ref HEAD >actual && + echo refs/heads/master >expect && + test_cmp expect actual && + git fsck + ) +' + +test_expect_success 'checkout --to a new worktree from a subdir' ' + ( + mkdir sub && + cd sub && + git checkout --detach --to here master && + cd here && + test_cmp ../../init.t init.t + ) +' + +test_expect_success 'checkout --to from a linked checkout' ' + ( + cd here && + git checkout --to nested-here master && + cd nested-here && + git fsck + ) +' + +test_expect_success 'checkout --to a new worktree creating new branch' ' + git checkout --to there -b newmaster master && + ( + cd there && + test_cmp ../init.t init.t && + git symbolic-ref HEAD >actual && + echo refs/heads/newmaster >expect && + test_cmp expect actual && + git fsck + ) +' + +test_done -- 2.11.4.GIT