worktree add: extend DWIM to infer --orphan

Extend DWIM to try to infer `--orphan` when in an empty repository. i.e.
a repository with an invalid/unborn HEAD, no local branches, and if
`--guess-remote` is used then no remote branches.

This behavior is equivalent to `git switch -c` or `git checkout -b` in
an empty repository.

Also warn the user (overriden with `-f`/`--force`) when they likely
intend to checkout a remote branch to the worktree but have not yet
fetched from the remote. i.e. when using `--guess-remote` and there is a
remote but no local or remote refs.

Current Behavior:
% git --no-pager branch --list --remotes
% git remote
origin
% git workree add ../main
hint: If you meant to create a worktree containing a new orphan branch
[...]
hint: Disable this message with "git config advice.worktreeAddOrphan false"
fatal: invalid reference: HEAD
% git workree add --guess-remote ../main
hint: If you meant to create a worktree containing a new orphan branch
[...]
hint: Disable this message with "git config advice.worktreeAddOrphan false"
fatal: invalid reference: HEAD
% git fetch --quiet
% git --no-pager branch --list --remotes
origin/HEAD -> origin/main
origin/main
% git workree add --guess-remote ../main
Preparing worktree (new branch 'main')
branch 'main' set up to track 'origin/main'.
HEAD is now at dadc8e6dac commit message
%

New Behavior:
% git --no-pager branch --list --remotes
% git remote
origin
% git workree add ../main
No possible source branch, inferring '--orphan'
Preparing worktree (new branch 'main')
% git worktree remove ../main
% git workree add --guess-remote ../main
fatal: No local or remote refs exist despite at least one remote
present, stopping; use 'add -f' to overide or fetch a remote first
% git workree add --guess-remote -f ../main
No possible source branch, inferring '--orphan'
Preparing worktree (new branch 'main')
% git worktree remove ../main
% git fetch --quiet
% git --no-pager branch --list --remotes
origin/HEAD -> origin/main
origin/main
% git workree add --guess-remote ../main
Preparing worktree (new branch 'main')
branch 'main' set up to track 'origin/main'.
HEAD is now at dadc8e6dac commit message
%

Signed-off-by: Jacob Abel <jacobabel@nullpo.dev>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Jacob Abel 2023-05-17 21:48:58 +00:00 committed by Junio C Hamano
parent 35f0383ca6
commit 128e5496b3
3 changed files with 449 additions and 1 deletions

View file

@ -95,6 +95,16 @@ exist, a new branch based on `HEAD` is automatically created as if
`-b <branch>` was given. If `<branch>` does exist, it will be checked out
in the new worktree, if it's not checked out anywhere else, otherwise the
command will refuse to create the worktree (unless `--force` is used).
+
If `<commit-ish>` is omitted, neither `--detach`, or `--orphan` is
used, and there are no valid local branches (or remote branches if
`--guess-remote` is specified) then, as a convenience, the new worktree is
associated with a new orphan branch named `<branch>` (after
`$(basename <path>)` if neither `-b` or `-B` is used) as if `--orphan` was
passed to the command. In the event the repository has a remote and
`--guess-remote` is used, but no remote or local branches exist, then the
command fails with a warning reminding the user to fetch from their remote
first (or override by using `-f/--force`).
list::

View file

@ -12,6 +12,7 @@
#include "strvec.h"
#include "branch.h"
#include "refs.h"
#include "remote.h"
#include "run-command.h"
#include "hook.h"
#include "sigchain.h"
@ -40,6 +41,9 @@
#define BUILTIN_WORKTREE_UNLOCK_USAGE \
N_("git worktree unlock <worktree>")
#define WORKTREE_ADD_DWIM_ORPHAN_INFER_TEXT \
_("No possible source branch, inferring '--orphan'")
#define WORKTREE_ADD_ORPHAN_WITH_DASH_B_HINT_TEXT \
_("If you meant to create a worktree containing a new orphan branch\n" \
"(branch with no commits) for this repository, you can do so\n" \
@ -613,6 +617,107 @@ static void print_preparing_worktree_line(int detach,
}
}
/**
* Callback to short circuit iteration over refs on the first reference
* corresponding to a valid oid.
*
* Returns 0 on failure and non-zero on success.
*/
static int first_valid_ref(const char *refname,
const struct object_id *oid,
int flags,
void *cb_data)
{
return 1;
}
/**
* Verifies HEAD and determines whether there exist any valid local references.
*
* - Checks whether HEAD points to a valid reference.
*
* - Checks whether any valid local branches exist.
*
* Returns 1 if any of the previous checks are true, otherwise returns 0.
*/
static int can_use_local_refs(const struct add_opts *opts)
{
if (head_ref(first_valid_ref, NULL)) {
return 1;
} else if (for_each_branch_ref(first_valid_ref, NULL)) {
return 1;
}
return 0;
}
/**
* Reports whether the necessary flags were set and whether the repository has
* remote references to attempt DWIM tracking of upstream branches.
*
* 1. Checks that `--guess-remote` was used or `worktree.guessRemote = true`.
*
* 2. Checks whether any valid remote branches exist.
*
* 3. Checks that there exists at least one remote and emits a warning/error
* if both checks 1. and 2. are false (can be bypassed with `--force`).
*
* Returns 1 if checks 1. and 2. are true, otherwise 0.
*/
static int can_use_remote_refs(const struct add_opts *opts)
{
if (!guess_remote) {
if (!opts->quiet)
fprintf_ln(stderr, WORKTREE_ADD_DWIM_ORPHAN_INFER_TEXT);
return 0;
} else if (for_each_remote_ref(first_valid_ref, NULL)) {
return 1;
} else if (!opts->force && remote_get(NULL)) {
die(_("No local or remote refs exist despite at least one remote\n"
"present, stopping; use 'add -f' to overide or fetch a remote first"));
} else if (!opts->quiet) {
fprintf_ln(stderr, WORKTREE_ADD_DWIM_ORPHAN_INFER_TEXT);
}
return 0;
}
/**
* Determines whether `--orphan` should be inferred in the evaluation of
* `worktree add path/` or `worktree add -b branch path/` and emits an error
* if the supplied arguments would produce an illegal combination when the
* `--orphan` flag is included.
*
* `opts` and `opt_track` contain the other options & flags supplied to the
* command.
*
* remote determines whether to check `can_use_remote_refs()` or not. This
* is primarily to differentiate between the basic `add` DWIM and `add -b`.
*
* Returns 1 when inferring `--orphan`, 0 otherwise, and emits an error when
* `--orphan` is inferred but doing so produces an illegal combination of
* options and flags. Additionally produces an error when remote refs are
* checked and the repo is in a state that looks like the user added a remote
* but forgot to fetch (and did not override the warning with -f).
*/
static int dwim_orphan(const struct add_opts *opts, int opt_track, int remote)
{
if (can_use_local_refs(opts)) {
return 0;
} else if (remote && can_use_remote_refs(opts)) {
return 0;
} else if (!opts->quiet) {
fprintf_ln(stderr, WORKTREE_ADD_DWIM_ORPHAN_INFER_TEXT);
}
if (opt_track) {
die(_("'%s' and '%s' cannot be used together"), "--orphan",
"--track");
} else if (!opts->checkout) {
die(_("'%s' and '%s' cannot be used together"), "--orphan",
"--no-checkout");
}
return 1;
}
static const char *dwim_branch(const char *path, const char **new_branch)
{
int n;
@ -723,12 +828,19 @@ static int add(int ac, const char **av, const char *prefix)
int n;
const char *s = worktree_basename(path, &n);
new_branch = xstrndup(s, n);
} else if (new_branch || opts.detach || opts.orphan) {
} else if (opts.orphan || opts.detach) {
// No-op
} else if (ac < 2 && new_branch) {
// DWIM: Infer --orphan when repo has no refs.
opts.orphan = dwim_orphan(&opts, !!opt_track, 0);
} else if (ac < 2) {
// DWIM: Guess branch name from path.
const char *s = dwim_branch(path, &new_branch);
if (s)
branch = s;
// DWIM: Infer --orphan when repo has no refs.
opts.orphan = (!s) && dwim_orphan(&opts, !!opt_track, 1);
} else if (ac == 2) {
struct object_id oid;
struct commit *commit;

View file

@ -705,6 +705,332 @@ test_expect_success 'git worktree --no-guess-remote option overrides config' '
)
'
test_dwim_orphan () {
local info_text="No possible source branch, inferring '--orphan'" &&
local fetch_error_text="fatal: No local or remote refs exist despite at least one remote" &&
local orphan_hint="hint: If you meant to create a worktree containing a new orphan branch" &&
local invalid_ref_regex="^fatal: invalid reference:\s\+.*" &&
local bad_combo_regex="^fatal: '[a-z-]\+' and '[a-z-]\+' cannot be used together" &&
local git_ns="repo" &&
local dashc_args="-C $git_ns" &&
local use_cd=0 &&
local bad_head=0 &&
local empty_repo=1 &&
local local_ref=0 &&
local use_quiet=0 &&
local remote=0 &&
local remote_ref=0 &&
local use_new_branch=0 &&
local outcome="$1" &&
local outcome_text &&
local success &&
shift &&
local args="" &&
local context="" &&
case "$outcome" in
"infer")
success=1 &&
outcome_text='"add" DWIM infer --orphan'
;;
"no_infer")
success=1 &&
outcome_text='"add" DWIM doesnt infer --orphan'
;;
"fetch_error")
success=0 &&
outcome_text='"add" error need fetch'
;;
"fatal_orphan_bad_combo")
success=0 &&
outcome_text='"add" error inferred "--orphan" gives illegal opts combo'
;;
*)
echo "test_dwim_orphan(): invalid outcome: '$outcome'" >&2 &&
return 1
;;
esac &&
while [ $# -gt 0 ]
do
case "$1" in
# How and from where to create the worktree
"-C_repo")
use_cd=0 &&
git_ns="repo" &&
dashc_args="-C $git_ns" &&
context="$context, 'git -C repo'"
;;
"-C_wt")
use_cd=0 &&
git_ns="wt" &&
dashc_args="-C $git_ns" &&
context="$context, 'git -C wt'"
;;
"cd_repo")
use_cd=1 &&
git_ns="repo" &&
dashc_args="" &&
context="$context, 'cd repo && git'"
;;
"cd_wt")
use_cd=1 &&
git_ns="wt" &&
dashc_args="" &&
context="$context, 'cd wt && git'"
;;
# Bypass the "pull first" warning
"force")
args="$args --force" &&
context="$context, --force"
;;
# Try to use remote refs when DWIM
"guess_remote")
args="$args --guess-remote" &&
context="$context, --guess-remote"
;;
"no_guess_remote")
args="$args --no-guess-remote" &&
context="$context, --no-guess-remote"
;;
# Whether there is at least one local branch present
"local_ref")
empty_repo=0 &&
local_ref=1 &&
context="$context, >=1 local branches"
;;
"no_local_ref")
empty_repo=0 &&
context="$context, 0 local branches"
;;
# Whether the HEAD points at a valid ref (skip this opt when no refs)
"good_head")
# requires: local_ref
context="$context, valid HEAD"
;;
"bad_head")
bad_head=1 &&
context="$context, invalid (or orphan) HEAD"
;;
# Whether the code path is tested with the base add command or -b
"no_-b")
use_new_branch=0 &&
context="$context, no --branch"
;;
"-b")
use_new_branch=1 &&
context="$context, --branch"
;;
# Whether to check that all output is suppressed (except errors)
# or that the output is as expected
"quiet")
use_quiet=1 &&
args="$args --quiet" &&
context="$context, --quiet"
;;
"no_quiet")
use_quiet=0 &&
context="$context, no --quiet (expect output)"
;;
# Whether there is at least one remote attached to the repo
"remote")
empty_repo=0 &&
remote=1 &&
context="$context, >=1 remotes"
;;
"no_remote")
empty_repo=0 &&
remote=0 &&
context="$context, 0 remotes"
;;
# Whether there is at least one valid remote ref
"remote_ref")
# requires: remote
empty_repo=0 &&
remote_ref=1 &&
context="$context, >=1 fetched remote branches"
;;
"no_remote_ref")
empty_repo=0 &&
remote_ref=0 &&
context="$context, 0 fetched remote branches"
;;
# Options or flags that become illegal when --orphan is inferred
"no_checkout")
args="$args --no-checkout" &&
context="$context, --no-checkout"
;;
"track")
args="$args --track" &&
context="$context, --track"
;;
# All other options are illegal
*)
echo "test_dwim_orphan(): invalid arg: '$1'" >&2 &&
return 1
;;
esac &&
shift
done &&
context="${context#', '}" &&
if [ $use_new_branch -eq 1 ]
then
args="$args -b foo"
else
context="DWIM (no --branch), $context"
fi &&
if [ $empty_repo -eq 1 ]
then
context="empty repo, $context"
fi &&
args="$args ../foo" &&
context="${context%', '}" &&
test_expect_success "$outcome_text w/ $context" '
test_when_finished "rm -rf repo" &&
git init repo &&
if [ $local_ref -eq 1 ] && [ "$git_ns" = "repo" ]
then
(cd repo && test_commit commit) &&
if [ $bad_head -eq 1 ]
then
git -C repo symbolic-ref HEAD refs/heads/badbranch
fi
elif [ $local_ref -eq 1 ] && [ "$git_ns" = "wt" ]
then
test_when_finished "git -C repo worktree remove -f ../wt" &&
git -C repo worktree add --orphan -b main ../wt &&
(cd wt && test_commit commit) &&
if [ $bad_head -eq 1 ]
then
git -C wt symbolic-ref HEAD refs/heads/badbranch
fi
elif [ $local_ref -eq 0 ] && [ "$git_ns" = "wt" ]
then
test_when_finished "git -C repo worktree remove -f ../wt" &&
git -C repo worktree add --orphan -b orphanbranch ../wt
fi &&
if [ $remote -eq 1 ]
then
test_when_finished "rm -rf upstream" &&
git init upstream &&
(cd upstream && test_commit commit) &&
git -C upstream switch -c foo &&
git -C repo remote add upstream ../upstream
fi &&
if [ $remote_ref -eq 1 ]
then
git -C repo fetch
fi &&
if [ $success -eq 1 ]
then
test_when_finished git -C repo worktree remove ../foo
fi &&
(
if [ $use_cd -eq 1 ]
then
cd $git_ns
fi &&
if [ "$outcome" = "infer" ]
then
git $dashc_args worktree add $args 2>actual &&
if [ $use_quiet -eq 1 ]
then
test_must_be_empty actual
else
grep "$info_text" actual
fi
elif [ "$outcome" = "no_infer" ]
then
git $dashc_args worktree add $args 2>actual &&
if [ $use_quiet -eq 1 ]
then
test_must_be_empty actual
else
! grep "$info_text" actual
fi
elif [ "$outcome" = "fetch_error" ]
then
test_must_fail git $dashc_args worktree add $args 2>actual &&
grep "$fetch_error_text" actual
elif [ "$outcome" = "fatal_orphan_bad_combo" ]
then
test_must_fail git $dashc_args worktree add $args 2>actual &&
if [ $use_quiet -eq 1 ]
then
! grep "$info_text" actual
else
grep "$info_text" actual
fi &&
grep "$bad_combo_regex" actual
elif [ "$outcome" = "warn_bad_head" ]
then
test_must_fail git $dashc_args worktree add $args 2>actual &&
if [ $use_quiet -eq 1 ]
then
grep "$invalid_ref_regex" actual &&
! grep "$orphan_hint" actual
else
headpath=$(git $dashc_args rev-parse --sq --path-format=absolute --git-path HEAD) &&
headcontents=$(cat "$headpath") &&
grep "HEAD points to an invalid (or orphaned) reference" actual &&
grep "HEAD path:\s*.$headpath." actual &&
grep "HEAD contents:\s*.$headcontents." actual &&
grep "$orphan_hint" actual &&
! grep "$info_text" actual
fi &&
grep "$invalid_ref_regex" actual
else
# Unreachable
false
fi
) &&
if [ $success -ne 1 ]
then
test_path_is_missing foo
fi
'
}
for quiet_mode in "no_quiet" "quiet"
do
for changedir_type in "cd_repo" "cd_wt" "-C_repo" "-C_wt"
do
dwim_test_args="$quiet_mode $changedir_type"
test_dwim_orphan 'infer' $dwim_test_args no_-b
test_dwim_orphan 'no_infer' $dwim_test_args no_-b local_ref good_head
test_dwim_orphan 'infer' $dwim_test_args no_-b no_local_ref no_remote no_remote_ref no_guess_remote
test_dwim_orphan 'infer' $dwim_test_args no_-b no_local_ref remote no_remote_ref no_guess_remote
test_dwim_orphan 'fetch_error' $dwim_test_args no_-b no_local_ref remote no_remote_ref guess_remote
test_dwim_orphan 'infer' $dwim_test_args no_-b no_local_ref remote no_remote_ref guess_remote force
test_dwim_orphan 'no_infer' $dwim_test_args no_-b no_local_ref remote remote_ref guess_remote
test_dwim_orphan 'infer' $dwim_test_args -b
test_dwim_orphan 'no_infer' $dwim_test_args -b local_ref good_head
test_dwim_orphan 'infer' $dwim_test_args -b no_local_ref no_remote no_remote_ref no_guess_remote
test_dwim_orphan 'infer' $dwim_test_args -b no_local_ref remote no_remote_ref no_guess_remote
test_dwim_orphan 'infer' $dwim_test_args -b no_local_ref remote no_remote_ref guess_remote
test_dwim_orphan 'infer' $dwim_test_args -b no_local_ref remote remote_ref guess_remote
done
test_dwim_orphan 'fatal_orphan_bad_combo' $quiet_mode no_-b no_checkout
test_dwim_orphan 'fatal_orphan_bad_combo' $quiet_mode no_-b track
test_dwim_orphan 'fatal_orphan_bad_combo' $quiet_mode -b no_checkout
test_dwim_orphan 'fatal_orphan_bad_combo' $quiet_mode -b track
done
post_checkout_hook () {
test_when_finished "rm -rf .git/hooks" &&
mkdir .git/hooks &&