From: Alexandr Miloslavskiy via GitGitGadget Date: Thu, 28 Nov 2019 19:32:16 GMT Subject: [PATCH 3/5] parse_branchname_arg(): update code comments Message-ID: <3918aafdbd6ae63ddb9b4ea7328b9ec2e0f76fe9.1574969538.git.gitgitgadget@gmail.com> In-Reply-To: From: Alexandr Miloslavskiy These parts repeat git documentation: ... if is A...B <...> ... remote named in checkout.defaultRemote ... Some parts repeat the code below. With next patch, code will be easier to understand, so this is no longer needed. This is a separate patch to reduce the amount of diffs in next patch. Signed-off-by: Alexandr Miloslavskiy --- builtin/checkout.c | 86 +++++++++++----------------------------------- 1 file changed, 21 insertions(+), 65 deletions(-) diff --git a/builtin/checkout.c b/builtin/checkout.c index 5c6131dbe6..723aaca0ef 100644 --- a/builtin/checkout.c +++ b/builtin/checkout.c @@ -1127,45 +1127,21 @@ static int parse_branchname_arg(int argc, const char **argv, int i; /* - * 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 [--] - * - * (a) 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. - * - * (b) If is _not_ a commit, either "--" is present - * or is not a path, no -t or -b was given, and - * and there is a tracking branch whose name is - * in one and only one remote (or if the branch exists on the - * remote named in checkout.defaultRemote), then this is a - * short-hand to fork local from that - * remote-tracking branch. - * - * (c) Otherwise, if "--" is present, treat it like case (1). - * - * (d) Otherwise : - * - if it's a reference, treat it like case (1) - * - else if it's a path, treat it like case (2) - * - else: fail. - * - * case 4: git checkout - * - * The first argument must 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. - * + * Resolve ambiguity where argv[0] may be or . + * High-level approach is: + * 1) Use various things to reduce ambiguity, examples: + * * '--' is present + * * command doesn't accept + * * additional options like '-b' were given + * 2) If ambiguous and matches both existing and existing + * file, complain. However, in 1-argument 'git checkout ' + * treat as to avoid annoying users. + * 3) Otherwise, if it matches some existing , treat as + * . + * 4) Otherwise, if it matches a remote branch, and it's considered + * reasonable to DWIM to create a local branch from remote branch, + * do that and proceed with (2)(3). + * 5) Otherwise, let caller proceed with interpretation. */ if (!argc) return 0; @@ -1187,9 +1163,9 @@ static int parse_branchname_arg(int argc, const char **argv, if (opts->accept_pathspec) { if (dash_dash_pos == 0) - return 1; /* case (2) */ + return 1; else if (dash_dash_pos == 1) - has_dash_dash = 1; /* case (3) or (1) */ + has_dash_dash = 1; else if (dash_dash_pos >= 2) die(_("only one reference expected, %d given."), dash_dash_pos); } @@ -1203,14 +1179,6 @@ static int parse_branchname_arg(int argc, const char **argv, arg = "@{-1}"; if (get_oid_mb(arg, rev)) { - /* - * Either case (3) or (4), with not being - * a commit, or an attempt to use case (1) with an - * invalid ref. - * - * It's likely an error, but we need to find out if - * we should auto-create the branch, case (3).(b). - */ int recover_with_dwim = dwim_new_local_branch_ok; int could_be_checkout_paths = !expect_commit_only && @@ -1219,10 +1187,6 @@ static int parse_branchname_arg(int argc, const char **argv, if (!expect_commit_only && !no_wildcard(arg)) recover_with_dwim = 0; - /* - * Accept "git checkout foo", "git checkout foo --" - * and "git switch foo" as candidates for dwim. - */ if (!(argc == 1 && !has_dash_dash) && !(argc == 2 && has_dash_dash) && opts->accept_pathspec) @@ -1238,7 +1202,7 @@ static int parse_branchname_arg(int argc, const char **argv, arg); *new_branch = arg; arg = remote; - /* DWIMmed to create local branch, case (3).(b) */ + /* DWIMmed to create local branch */ } else { recover_with_dwim = 0; } @@ -1253,19 +1217,11 @@ static int parse_branchname_arg(int argc, const char **argv, setup_new_branch_info_and_source_tree(new_branch_info, opts, rev, arg); - if (!opts->source_tree) /* case (1): want a tree */ + if (!opts->source_tree) die(_("reference is not a tree: %s"), arg); - if (!expect_commit_only) { /* case (3).(d) -> (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 > 1) - verify_non_filename(opts->prefix, arg); - } + if (!expect_commit_only && argc > 1) + verify_non_filename(opts->prefix, arg); return (dash_dash_pos == 1) ? 2 : 1; } -- gitgitgadget