notes: allow treeish expressions as notes ref

init_notes() is the main point of entry to the notes API. It ensures
that the input can be used as ref, because it needs a ref to update to
store notes tree after modifying it.

There however are many use cases where notes tree is only read, e.g.
"git log --notes=...".  Any notes-shaped treeish could be used for such
purpose, but it is not allowed due to existing restriction.

Allow treeish expressions to be used in the case the notes tree is going
to be used without write "permissions".  Add a flag to distinguish
whether the notes tree is intended to be used read-only, or will be
updated.

With this change, operations that use notes read-only can be fed any
notes-shaped tree-ish can be used, e.g. git log --notes=notes@{1}.

Signed-off-by: Mike Hommey <mh@glandium.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/pretty-options.txt b/Documentation/pretty-options.txt
index 4b659ac1a6a6c1b57d0cadc5cd69ce6b69525cc1..54b88b6dcaaa5df06fc8dad2e5f5172682269bc9 100644 (file)
--- a/Documentation/pretty-options.txt
+++ b/Documentation/pretty-options.txt
@@ -43,7 +43,7 @@ people using 80-column terminals.
        commit may be copied to the output.
 
 ifndef::git-rev-list[]
---notes[=<ref>]::
+--notes[=<treeish>]::
        Show the notes (see linkgit:git-notes[1]) that annotate the
        commit, when showing the commit log message.  This is the default
        for `git log`, `git show` and `git whatchanged` commands when
@@ -54,8 +54,8 @@ By default, the notes shown are from the notes refs listed in the
 'core.notesRef' and 'notes.displayRef' variables (or corresponding
 environment overrides). See linkgit:git-config[1] for more details.
 +
-With an optional '<ref>' argument, show this notes ref instead of the
-default notes ref(s). The ref specifies the full refname when it begins
+With an optional '<treeish>' argument, use the treeish to find the notes
+to display.  The treeish can specify the full refname when it begins
 with `refs/notes/`; when it begins with `notes/`, `refs/` and otherwise
 `refs/notes/` is prefixed to form a full name of the ref.
 +
@@ -71,7 +71,7 @@ being displayed. Examples: "--notes=foo" will show only notes from
        "--notes --notes=foo --no-notes --notes=bar" will only show notes
        from "refs/notes/bar".
 
---show-notes[=<ref>]::
+--show-notes[=<treeish>]::
 --[no-]standard-notes::
        These options are deprecated. Use the above --notes/--no-notes
        options instead.

diff --git a/builtin/notes.c b/builtin/notes.c
index 52aa9af74be8d47780d4762185c5cbe09624b382..e1556896f9ea653f562e073f9ec23bfdcd0d4d7b 100644 (file)
--- a/builtin/notes.c
+++ b/builtin/notes.c
@@ -286,7 +286,7 @@ static int notes_copy_from_stdin(int force, const char *rewrite_cmd)
                if (!c)
                        return 0;
        } else {
-               init_notes(NULL, NULL, NULL, 0);
+               init_notes(NULL, NULL, NULL, NOTES_INIT_WRITABLE);
                t = &default_notes_tree;
        }
 
@@ -329,15 +329,18 @@ static int notes_copy_from_stdin(int force, const char *rewrite_cmd)
        return ret;
 }
 
-static struct notes_tree *init_notes_check(const char *subcommand)
+static struct notes_tree *init_notes_check(const char *subcommand,
+                                          int flags)
 {
        struct notes_tree *t;
-       init_notes(NULL, NULL, NULL, 0);
+       const char *ref;
+       init_notes(NULL, NULL, NULL, flags);
        t = &default_notes_tree;
 
-       if (!starts_with(t->ref, "refs/notes/"))
+       ref = (flags & NOTES_INIT_WRITABLE) ? t->update_ref : t->ref;
+       if (!starts_with(ref, "refs/notes/"))
                die("Refusing to %s notes in %s (outside of refs/notes/)",
-                   subcommand, t->ref);
+                   subcommand, ref);
        return t;
 }
 
@@ -360,7 +363,7 @@ static int list(int argc, const char **argv, const char *prefix)
                usage_with_options(git_notes_list_usage, options);
        }
 
-       t = init_notes_check("list");
+       t = init_notes_check("list", 0);
        if (argc) {
                if (get_sha1(argv[0], object))
                        die(_("Failed to resolve '%s' as a valid ref."), argv[0]);
@@ -420,7 +423,7 @@ static int add(int argc, const char **argv, const char *prefix)
        if (get_sha1(object_ref, object))
                die(_("Failed to resolve '%s' as a valid ref."), object_ref);
 
-       t = init_notes_check("add");
+       t = init_notes_check("add", NOTES_INIT_WRITABLE);
        note = get_note(t, object);
 
        if (note) {
@@ -511,7 +514,7 @@ static int copy(int argc, const char **argv, const char *prefix)
        if (get_sha1(object_ref, object))
                die(_("Failed to resolve '%s' as a valid ref."), object_ref);
 
-       t = init_notes_check("copy");
+       t = init_notes_check("copy", NOTES_INIT_WRITABLE);
        note = get_note(t, object);
 
        if (note) {
@@ -589,7 +592,7 @@ static int append_edit(int argc, const char **argv, const char *prefix)
        if (get_sha1(object_ref, object))
                die(_("Failed to resolve '%s' as a valid ref."), object_ref);
 
-       t = init_notes_check(argv[0]);
+       t = init_notes_check(argv[0], NOTES_INIT_WRITABLE);
        note = get_note(t, object);
 
        prepare_note_data(object, &d, edit ? note : NULL);
@@ -652,7 +655,7 @@ static int show(int argc, const char **argv, const char *prefix)
        if (get_sha1(object_ref, object))
                die(_("Failed to resolve '%s' as a valid ref."), object_ref);
 
-       t = init_notes_check("show");
+       t = init_notes_check("show", 0);
        note = get_note(t, object);
 
        if (!note)
@@ -809,7 +812,7 @@ static int merge(int argc, const char **argv, const char *prefix)
        expand_notes_ref(&remote_ref);
        o.remote_ref = remote_ref.buf;
 
-       t = init_notes_check("merge");
+       t = init_notes_check("merge", NOTES_INIT_WRITABLE);
 
        if (strategy) {
                if (parse_notes_merge_strategy(strategy, &o.strategy)) {
@@ -901,7 +904,7 @@ static int remove_cmd(int argc, const char **argv, const char *prefix)
        argc = parse_options(argc, argv, prefix, options,
                             git_notes_remove_usage, 0);
 
-       t = init_notes_check("remove");
+       t = init_notes_check("remove", NOTES_INIT_WRITABLE);
 
        if (!argc && !from_stdin) {
                retval = remove_one_note(t, "HEAD", flag);
@@ -943,7 +946,7 @@ static int prune(int argc, const char **argv, const char *prefix)
                usage_with_options(git_notes_prune_usage, options);
        }
 
-       t = init_notes_check("prune");
+       t = init_notes_check("prune", NOTES_INIT_WRITABLE);
 
        prune_notes(t, (verbose ? NOTES_PRUNE_VERBOSE : 0) |
                (show_only ? NOTES_PRUNE_VERBOSE|NOTES_PRUNE_DRYRUN : 0) );

diff --git a/notes-cache.c b/notes-cache.c
index c4e9bb7f6c0bde97c7c6d34094baa5ef7e318157..5dfc5cbd08e496748880bda6a67264c7d63f68b4 100644 (file)
--- a/notes-cache.c
+++ b/notes-cache.c
@@ -32,14 +32,14 @@ void notes_cache_init(struct notes_cache *c, const char *name,
                     const char *validity)
 {
        struct strbuf ref = STRBUF_INIT;
-       int flags = 0;
+       int flags = NOTES_INIT_WRITABLE;
 
        memset(c, 0, sizeof(*c));
        c->validity = xstrdup(validity);
 
        strbuf_addf(&ref, "refs/notes/%s", name);
        if (!notes_cache_match_validity(ref.buf, validity))
-               flags = NOTES_INIT_EMPTY;
+               flags |= NOTES_INIT_EMPTY;
        init_notes(&c->tree, ref.buf, combine_notes_overwrite, flags);
        strbuf_release(&ref);
 }
@@ -49,7 +49,8 @@ int notes_cache_write(struct notes_cache *c)
        unsigned char tree_sha1[20];
        unsigned char commit_sha1[20];
 
-       if (!c || !c->tree.initialized || !c->tree.ref || !*c->tree.ref)
+       if (!c || !c->tree.initialized || !c->tree.update_ref ||
+           !*c->tree.update_ref)
                return -1;
        if (!c->tree.dirty)
                return 0;
@@ -59,8 +60,8 @@ int notes_cache_write(struct notes_cache *c)
        if (commit_tree(c->validity, strlen(c->validity), tree_sha1, NULL,
                        commit_sha1, NULL, NULL) < 0)
                return -1;
-       if (update_ref("update notes cache", c->tree.ref, commit_sha1, NULL,
-                      0, UPDATE_REFS_QUIET_ON_ERR) < 0)
+       if (update_ref("update notes cache", c->tree.update_ref, commit_sha1,
+                      NULL, 0, UPDATE_REFS_QUIET_ON_ERR) < 0)
                return -1;
 
        return 0;

diff --git a/notes-utils.c b/notes-utils.c
index 299e34bccc5893529cb5db1abe061529304e6074..24a33616a47737e6ae8cf917080cbb314dcf2762 100644 (file)
--- a/notes-utils.c
+++ b/notes-utils.c
@@ -37,7 +37,7 @@ void commit_notes(struct notes_tree *t, const char *msg)
 
        if (!t)
                t = &default_notes_tree;
-       if (!t->initialized || !t->ref || !*t->ref)
+       if (!t->initialized || !t->update_ref || !*t->update_ref)
                die(_("Cannot commit uninitialized/unreferenced notes tree"));
        if (!t->dirty)
                return; /* don't have to commit an unchanged tree */
@@ -48,7 +48,7 @@ void commit_notes(struct notes_tree *t, const char *msg)
 
        create_notes_commit(t, NULL, buf.buf, buf.len, commit_sha1);
        strbuf_insert(&buf, 0, "notes: ", 7); /* commit message starts at index 7 */
-       update_ref(buf.buf, t->ref, commit_sha1, NULL, 0,
+       update_ref(buf.buf, t->update_ref, commit_sha1, NULL, 0,
                   UPDATE_REFS_DIE_ON_ERR);
 
        strbuf_release(&buf);
@@ -148,7 +148,7 @@ struct notes_rewrite_cfg *init_copy_notes_for_rewrite(const char *cmd)
                free(c);
                return NULL;
        }
-       c->trees = load_notes_trees(c->refs);
+       c->trees = load_notes_trees(c->refs, NOTES_INIT_WRITABLE);
        string_list_clear(c->refs, 0);
        free(c->refs);
        return c;

diff --git a/notes.c b/notes.c
index db77922130b4f7df6ab72122206a76d6c580faac..358e2fdb74eb8cc92f16b33891a9a5f0a508de9c 100644 (file)
--- a/notes.c
+++ b/notes.c
@@ -1011,13 +1011,16 @@ void init_notes(struct notes_tree *t, const char *notes_ref,
        t->first_non_note = NULL;
        t->prev_non_note = NULL;
        t->ref = xstrdup_or_null(notes_ref);
+       t->update_ref = (flags & NOTES_INIT_WRITABLE) ? t->ref : NULL;
        t->combine_notes = combine_notes;
        t->initialized = 1;
        t->dirty = 0;
 
        if (flags & NOTES_INIT_EMPTY || !notes_ref ||
-           read_ref(notes_ref, object_sha1))
+           get_sha1_treeish(notes_ref, object_sha1))
                return;
+       if (flags & NOTES_INIT_WRITABLE && read_ref(notes_ref, object_sha1))
+               die("Cannot use notes ref %s", notes_ref);
        if (get_tree_entry(object_sha1, "", sha1, &mode))
                die("Failed to read notes tree referenced by %s (%s)",
                    notes_ref, sha1_to_hex(object_sha1));
@@ -1027,7 +1030,7 @@ void init_notes(struct notes_tree *t, const char *notes_ref,
        load_subtree(t, &root_tree, t->root, 0);
 }
 
-struct notes_tree **load_notes_trees(struct string_list *refs)
+struct notes_tree **load_notes_trees(struct string_list *refs, int flags)
 {
        struct string_list_item *item;
        int counter = 0;
@@ -1035,7 +1038,7 @@ struct notes_tree **load_notes_trees(struct string_list *refs)
        trees = xmalloc((refs->nr+1) * sizeof(struct notes_tree *));
        for_each_string_list_item(item, refs) {
                struct notes_tree *t = xcalloc(1, sizeof(struct notes_tree));
-               init_notes(t, item->string, combine_notes_ignore, 0);
+               init_notes(t, item->string, combine_notes_ignore, flags);
                trees[counter++] = t;
        }
        trees[counter] = NULL;
@@ -1071,7 +1074,7 @@ void init_display_notes(struct display_notes_opt *opt)
                                                     item->string);
        }
 
-       display_notes_trees = load_notes_trees(&display_notes_refs);
+       display_notes_trees = load_notes_trees(&display_notes_refs, 0);
        string_list_clear(&display_notes_refs, 0);
 }
 

diff --git a/notes.h b/notes.h
index 2a3f92338076ef8e4b8238aaf570c3273b0f28f0..e5d67fd3754aab644791f2062d3789b38cf6bd38 100644 (file)
--- a/notes.h
+++ b/notes.h
@@ -44,6 +44,7 @@ extern struct notes_tree {
        struct int_node *root;
        struct non_note *first_non_note, *prev_non_note;
        char *ref;
+       char *update_ref;
        combine_notes_fn combine_notes;
        int initialized;
        int dirty;
@@ -71,6 +72,13 @@ const char *default_notes_ref(void);
  */
 #define NOTES_INIT_EMPTY 1
 
+/*
+ * By default, the notes tree is only readable, and the notes ref can be
+ * any treeish. The notes tree can however be made writable with this flag,
+ * in which case only strict ref names can be used.
+ */
+#define NOTES_INIT_WRITABLE 2
+
 /*
  * Initialize the given notes_tree with the notes tree structure at the given
  * ref. If given ref is NULL, the value of the $GIT_NOTES_REF environment
@@ -276,7 +284,7 @@ void format_display_notes(const unsigned char *object_sha1,
  * Load the notes tree from each ref listed in 'refs'.  The output is
  * an array of notes_tree*, terminated by a NULL.
  */
-struct notes_tree **load_notes_trees(struct string_list *refs);
+struct notes_tree **load_notes_trees(struct string_list *refs, int flags);
 
 /*
  * Add all refs that match 'glob' to the 'list'.

diff --git a/t/t3301-notes.sh b/t/t3301-notes.sh
index cd70274ea51ac5c5ba6669495b944da5b7b97431..2d200fdf36c62c12cbbf2a964d3489edef401257 100755 (executable)
--- a/t/t3301-notes.sh
+++ b/t/t3301-notes.sh
@@ -83,6 +83,16 @@ test_expect_success 'edit existing notes' '
        test_must_fail git notes show HEAD^
 '
 
+test_expect_success 'show notes from treeish' '
+       test "b3" = "$(git notes --ref commits^{tree} show)" &&
+       test "b4" = "$(git notes --ref commits@{1} show)"
+'
+
+test_expect_success 'cannot edit notes from non-ref' '
+       test_must_fail git notes --ref commits^{tree} edit &&
+       test_must_fail git notes --ref commits@{1} edit
+'
+
 test_expect_success 'cannot "git notes add -m" where notes already exists' '
        test_must_fail git notes add -m "b2" &&
        test_path_is_missing .git/NOTES_EDITMSG &&