Re: [PATCH v5 1/3] ref-filter: add worktreepath atom
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jan 7, 2019, 18:20 UTC
- Message-ID
- <xmqq5zv09vns.fsf@gitster-ct.c.googlers.com>
- In-Reply-To
- <20190106002619.54741-2-nbelakovski@gmail.com>
nbelakovski@gmail.com writes:
Show 19 quoted lines
> +static struct hashmap ref_to_worktree_map;
> +static struct worktree **worktrees = NULL;
> +
> /*
> * An atom is a valid field atom listed below, possibly prefixed with
> * a "*" to denote deref_tag().
> @@ -420,6 +438,34 @@ static int head_atom_parser(const struct ref_format *format, struct used_atom *a
> return 0;
> }
>
> +static int worktree_atom_parser(const struct ref_format *format,
> + struct used_atom *atom,
> + const char *arg,
> + struct strbuf *unused_err)
> +{
> + int i;
> +
> + if (worktrees)
> + return 0;OK, so verify_ref_format() etc. will trigger this to be called via valid_atom[].parser when "%(worktreepath)" is seen in the user format, and then this grabs all the worktrees and record their paths in the hashmap. This if() statement makes sure that it happens only once.
Show 38 quoted lines
> + worktrees = get_worktrees(0);
> +
> + hashmap_init(&ref_to_worktree_map, ref_to_worktree_map_cmpfnc, NULL, 0);
> +
> + for (i = 0; worktrees[i]; i++) {
> + if (worktrees[i]->head_ref) {
> + struct ref_to_worktree_entry *entry;
> + entry = xmalloc(sizeof(*entry));
> + entry->wt = worktrees[i];
> + hashmap_entry_init(entry, strhash(worktrees[i]->head_ref));
> +
> + hashmap_add(&ref_to_worktree_map, entry);
> + }
> + }
> +
> + return 0;
> +}
> +
> static struct {
> const char *name;
> info_source source;
> @@ -461,6 +507,7 @@ static struct {
> { "flag", SOURCE_NONE },
> { "HEAD", SOURCE_NONE, FIELD_STR, head_atom_parser },
> { "color", SOURCE_NONE, FIELD_STR, color_atom_parser },
> + { "worktreepath", SOURCE_NONE, FIELD_STR, worktree_atom_parser },
> { "align", SOURCE_NONE, FIELD_STR, align_atom_parser },
> { "end", SOURCE_NONE },
> { "if", SOURCE_NONE, FIELD_STR, if_atom_parser },
> @@ -1500,6 +1547,21 @@ static int get_object(struct ref_array_item *ref, int deref, struct object **obj
> return 0;
> }
>
> +static char *get_worktree_path(const struct used_atom *atom, const struct ref_array_item *ref)
> +{
> + struct strbuf val = STRBUF_INIT;
> + struct hashmap_entry entry;
> + struct ref_to_worktree_entry *lookup_result;And then this will be called from populate_value() for each of the ref. It looks up the worktree that has checked out this branch, if any, from the hashmap, and yields the path to it.
When seeing a tag or note ref, by definition that's not something we can have checked out in any worktree. I wonder if it is worth to optimize further by omitting this lookup when ref is not a local branch?
IOW, with a typical number of worktrees and refs, how costly would ...
> + hashmap_entry_init(&entry, strhash(ref->refname)); > + lookup_result = hashmap_get(&ref_to_worktree_map, &entry, ref->refname);
... this sequence of calls be.
Show 27 quoted lines
> +
> + if (lookup_result)
> + strbuf_addstr(&val, lookup_result->wt->path);
> +
> + return strbuf_detach(&val, NULL);
> +}
> +
> /*
> * Parse the object referred by ref, and grab needed value.
> */
> @@ -1537,6 +1599,10 @@ static int populate_value(struct ref_array_item *ref, struct strbuf *err)
>
> if (starts_with(name, "refname"))
> refname = get_refname(atom, ref);
> + else if (starts_with(name, "worktreepath")) {
> + v->s = get_worktree_path(atom, ref);
> + continue;
> + }
> else if (starts_with(name, "symref"))
> refname = get_symref(atom, ref);
> else if (starts_with(name, "upstream")) {
> @@ -2020,6 +2086,11 @@ void ref_array_clear(struct ref_array *array)
> free_array_item(array->items[i]);
> FREE_AND_NULL(array->items);
> array->nr = array->alloc = 0;
> + if (worktrees)
> + {Have this opening brace at the end of the previous line, i.e.
if (worktrees) {> + hashmap_free(&ref_to_worktree_map, 1); > + free_worktrees(worktrees); > + } > }
What's the point of ref_array_clear()? What does the caller of this function really want? Is it merely to release the resources consumed? If so, then this is good enough, but then the existing calls to FREE_AND_NULL() for releasing resources in the function is overkill.
Or is it envisioned that we are preparing a clean slate so that another call, possibly after the external environment changed, can be made into this machinery (i.e. imagine we lift ref-filter.c code and link it to a long running service process; after serving one for-each-ref request, a new worktree or a new branch may get created, and then we may get another for-each-ref request)? If that is the case, then the added code breaks that hope, as it leaves a dangling pointer in the worktrees variable.
Show 25 quoted lines
> static void do_merge_filter(struct ref_filter_cbdata *ref_cbdata) > diff --git a/t/t6302-for-each-ref-filter.sh b/t/t6302-for-each-ref-filter.sh > index fc067ed672..87e0222ea1 100755 > --- a/t/t6302-for-each-ref-filter.sh > +++ b/t/t6302-for-each-ref-filter.sh > @@ -441,4 +441,19 @@ test_expect_success '--merged is incompatible with --no-merged' ' > test_must_fail git for-each-ref --merged HEAD --no-merged HEAD > ' > > +test_expect_success '"add" a worktree' ' > + mkdir worktree_dir && > + git worktree add -b master_worktree worktree_dir master > +' > + > +test_expect_success 'validate worktree atom' ' > + cat >expect <<-EOF && > + master: $(pwd) > + master_worktree: $(pwd)/worktree_dir > + side: not checked out > + EOF > + git for-each-ref --format="%(refname:short): %(if)%(worktreepath)%(then)%(worktreepath)%(else)not checked out%(end)" refs/heads/ >actual && > + test_cmp expect actual > +' > + > test_done