From 09ebad6faeec11c3dbad0bdaf95faed57be5dcba Mon Sep 17 00:00:00 2001 From: Jonathan Nieder Date: Tue, 8 Feb 2011 04:29:09 -0600 Subject: [PATCH] checkout: split off a function to peel away branchname arg The code to parse and consume the tree name and "--" in commands such as "git checkout @{-1} -- '*.c'" is intimidatingly long. Split it out into a separate function and make it easier to skip on first reading by making the data it uses and produces more explicit. No functional change intended. Signed-off-by: Jonathan Nieder Signed-off-by: Junio C Hamano --- builtin/checkout.c | 229 ++++++++++++++++++++++++++------------------- 1 file changed, 131 insertions(+), 98 deletions(-) diff --git a/builtin/checkout.c b/builtin/checkout.c index 953abdd0f..0e7a6a395 100644 --- a/builtin/checkout.c +++ b/builtin/checkout.c @@ -675,11 +675,123 @@ static const char *unique_tracking_name(const char *name) return NULL; } +static int parse_branchname_arg(int argc, const char **argv, + int dwim_new_local_branch_ok, + struct branch_info *new, + struct tree **source_tree, + unsigned char rev[20], + const char **new_branch) +{ + int argcount = 0; + unsigned char branch_rev[20]; + const char *arg; + int has_dash_dash; + + /* + * case 1: git checkout -- [] + * + * must be a valid tree, everything after the '--' must be + * a path. + * + * case 2: git checkout -- [] + * + * everything after the '--' must be paths. + * + * case 3: git checkout [] + * + * With no paths, if is a commit, that is to + * switch to the branch or detach HEAD at it. As a special case, + * if is A...B (missing A or B means HEAD but you can + * omit at most one side), and if there is a unique merge base + * between A and B, A...B names that merge base. + * + * With no paths, if is _not_ a commit, no -t nor -b + * was given, and there is a tracking branch whose name is + * in one and only one remote, then this is a short-hand + * to fork local from that remote tracking branch. + * + * Otherwise shall not be ambiguous. + * - If it's *only* a reference, treat it like case (1). + * - If it's only a path, treat it like case (2). + * - else: fail. + * + */ + if (!argc) + return 0; + + if (!strcmp(argv[0], "--")) /* case (2) */ + return 1; + + arg = argv[0]; + has_dash_dash = (argc > 1) && !strcmp(argv[1], "--"); + + if (!strcmp(arg, "-")) + arg = "@{-1}"; + + if (get_sha1_mb(arg, rev)) { + if (has_dash_dash) /* case (1) */ + die("invalid reference: %s", arg); + if (dwim_new_local_branch_ok && + !check_filename(NULL, arg) && + argc == 1) { + const char *remote = unique_tracking_name(arg); + if (!remote || get_sha1(remote, rev)) + return argcount; + *new_branch = arg; + arg = remote; + /* DWIMmed to create local branch */ + } else { + return argcount; + } + } + + /* we can't end up being in (2) anymore, eat the argument */ + argcount++; + argv++; + argc--; + + new->name = arg; + setup_branch_path(new); + + if (check_ref_format(new->path) == CHECK_REF_FORMAT_OK && + resolve_ref(new->path, branch_rev, 1, NULL)) + hashcpy(rev, branch_rev); + else + new->path = NULL; /* not an existing branch */ + + new->commit = lookup_commit_reference_gently(rev, 1); + if (!new->commit) { + /* not a commit */ + *source_tree = parse_tree_indirect(rev); + } else { + parse_commit(new->commit); + *source_tree = new->commit->tree; + } + + if (!*source_tree) /* case (1): want a tree */ + die("reference is not a tree: %s", arg); + if (!has_dash_dash) {/* case (3 -> 1) */ + /* + * Do not complain the most common case + * git checkout branch + * even if there happen to be a file called 'branch'; + * it would be extremely annoying. + */ + if (argc) + verify_non_filename(NULL, arg); + } else { + argcount++; + argv++; + argc--; + } + + return argcount; +} + int cmd_checkout(int argc, const char **argv, const char *prefix) { struct checkout_opts opts; - unsigned char rev[20], branch_rev[20]; - const char *arg; + unsigned char rev[20]; struct branch_info new; struct tree *source_tree = NULL; char *conflict_style = NULL; @@ -709,7 +821,6 @@ int cmd_checkout(int argc, const char **argv, const char *prefix) PARSE_OPT_NOARG | PARSE_OPT_HIDDEN }, OPT_END(), }; - int has_dash_dash; memset(&opts, 0, sizeof(opts)); memset(&new, 0, sizeof(new)); @@ -766,108 +877,30 @@ int cmd_checkout(int argc, const char **argv, const char *prefix) die("git checkout: -f and -m are incompatible"); /* - * case 1: git checkout -- [] - * - * must be a valid tree, everything after the '--' must be - * a path. - * - * case 2: git checkout -- [] - * - * everything after the '--' must be paths. + * Extract branch name from command line arguments, so + * all that is left is pathspecs. * - * case 3: git checkout [] - * - * With no paths, if is a commit, that is to - * switch to the branch or detach HEAD at it. As a special case, - * if is A...B (missing A or B means HEAD but you can - * omit at most one side), and if there is a unique merge base - * between A and B, A...B names that merge base. - * - * With no paths, if is _not_ a commit, no -t nor -b - * was given, and there is a tracking branch whose name is - * in one and only one remote, then this is a short-hand - * to fork local from that remote tracking branch. + * Handle * - * Otherwise shall not be ambiguous. - * - If it's *only* a reference, treat it like case (1). - * - If it's only a path, treat it like case (2). - * - else: fail. + * 1) git checkout -- [] + * 2) git checkout -- [] + * 3) git checkout [] * + * including "last branch" syntax and DWIM-ery for names of + * remote branches, erroring out for invalid or ambiguous cases. */ if (argc) { - if (!strcmp(argv[0], "--")) { /* case (2) */ - argv++; - argc--; - goto no_reference; - } - - arg = argv[0]; - has_dash_dash = (argc > 1) && !strcmp(argv[1], "--"); - - if (!strcmp(arg, "-")) - arg = "@{-1}"; - - if (get_sha1_mb(arg, rev)) { - if (has_dash_dash) /* case (1) */ - die("invalid reference: %s", arg); - if (!patch_mode && - dwim_new_local_branch && - opts.track == BRANCH_TRACK_UNSPECIFIED && - !opts.new_branch && - !check_filename(NULL, arg) && - argc == 1) { - const char *remote = unique_tracking_name(arg); - if (!remote || get_sha1(remote, rev)) - goto no_reference; - opts.new_branch = arg; - arg = remote; - /* DWIMmed to create local branch */ - } - else - goto no_reference; - } - - /* we can't end up being in (2) anymore, eat the argument */ - argv++; - argc--; - - new.name = arg; - setup_branch_path(&new); - - if (check_ref_format(new.path) == CHECK_REF_FORMAT_OK && - resolve_ref(new.path, branch_rev, 1, NULL)) - hashcpy(rev, branch_rev); - else - new.path = NULL; /* not an existing branch */ - - if (!(new.commit = lookup_commit_reference_gently(rev, 1))) { - /* not a commit */ - source_tree = parse_tree_indirect(rev); - } else { - parse_commit(new.commit); - source_tree = new.commit->tree; - } - - if (!source_tree) /* case (1): want a tree */ - die("reference is not a tree: %s", arg); - if (!has_dash_dash) {/* case (3 -> 1) */ - /* - * Do not complain the most common case - * git checkout branch - * even if there happen to be a file called 'branch'; - * it would be extremely annoying. - */ - if (argc) - verify_non_filename(NULL, arg); - } - else { - argv++; - argc--; - } + int dwim_ok = + !patch_mode && + dwim_new_local_branch && + opts.track == BRANCH_TRACK_UNSPECIFIED && + !opts.new_branch; + int n = parse_branchname_arg(argc, argv, dwim_ok, + &new, &source_tree, rev, &opts.new_branch); + argv += n; + argc -= n; } -no_reference: - if (opts.track == BRANCH_TRACK_UNSPECIFIED) opts.track = git_branch_track; -- 2.30.2