cat-file ambiguity prints "dangling"

cat-file ambiguity prints "dangling"

[Eric Wong]

Hi David,

Perhaps I'm confused, the cat-file manpage seems to indicate
"dangling" only gets printed if I use "--follow-symlinks".

However, I'm not using "--follow-symlinks" and I get
"dangling" when passing ambiguous object IDs:

Trying to check the ambiguous "dead" against git.git, I get:

	$ echo dead | git cat-file --batch-check 2>/dev/null
	dangling 4
	dead

Is the above intended?

stderr shows the ambiguity and gives me hints, which is expected.

Thanks.

Re: cat-file ambiguity prints "dangling"

[David Turner]

[-- Attachment #1: Type: text/plain, Size: 838 bytes --]

It appears that get_oid_with_context calls into get_short_oid for that
case, and get_short_oid returns SHORT_NAME_AMBIGUOUS, which is -2.  We
treat that as DANGLING_SYMLINK, which also seems to have the value -2. 
So, it's an ambiguity in ambiguity resolution.

Fix attached.  

On Fri, 2019-01-18 at 03:38 +0000, Eric Wong wrote:
> Hi David,
> 
> Perhaps I'm confused, the cat-file manpage seems to indicate
> "dangling" only gets printed if I use "--follow-symlinks".
> 
> However, I'm not using "--follow-symlinks" and I get
> "dangling" when passing ambiguous object IDs:
> 
> Trying to check the ambiguous "dead" against git.git, I get:
> 
> 	$ echo dead | git cat-file --batch-check 2>/dev/null
> 	dangling 4
> 	dead
> 
> Is the above intended?
> 
> stderr shows the ambiguity and gives me hints, which is expected.
> 
> Thanks.
> 

[-- Attachment #2: 0001-Do-not-print-dangling-for-cat-file-in-case-of-ambigu.patch --]
[-- Type: text/x-patch, Size: 10328 bytes --]

From 319a4c76f1939a004775a3440d504e14f53074f3 Mon Sep 17 00:00:00 2001
From: David Turner <novalis@novalis.org>
Date: Thu, 17 Jan 2019 23:19:43 -0500
Subject: [PATCH] Do not print 'dangling' for cat-file in case of ambiguity

The return values -1 and -2 from get_oid could mean two different
things, depending on whether they were from an enum returned by
get_tree_entry_follow_symlinks, or from a different code path.  This
caused 'dangling' to be printed from a git cat-file in the case of an
ambiguous (-2) result.

Unify the results of get_oid* and get_tree_entry_follow_symlinks to be
one common type, with unambiguous values.

Signed-off-by: David Turner <novalis@novalis.org>
Reported-by: Eric Wong <e@80x24.org>
---
 builtin/cat-file.c |  5 +++-
 cache.h            | 20 +++++++++++++++-
 sha1-name.c        | 58 ++++++++++++++++++++++++----------------------
 tree-walk.c        |  4 ++--
 tree-walk.h        | 18 +-------------
 5 files changed, 56 insertions(+), 49 deletions(-)

diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index 2ca56fd086..f2344b199f 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -380,7 +380,7 @@ static void batch_one_object(const char *obj_name,
 {
 	struct object_context ctx;
 	int flags = opt->follow_symlinks ? GET_OID_FOLLOW_SYMLINKS : 0;
-	enum follow_symlinks_result result;
+	enum get_oid_result result;
 
 	result = get_oid_with_context(obj_name, flags, &data->oid, &ctx);
 	if (result != FOUND) {
@@ -388,6 +388,9 @@ static void batch_one_object(const char *obj_name,
 		case MISSING_OBJECT:
 			printf("%s missing\n", obj_name);
 			break;
+		case SHORT_NAME_AMBIGUOUS:
+			/* We've already printed the ambiguous message */
+			break;
 		case DANGLING_SYMLINK:
 			printf("dangling %"PRIuMAX"\n%s\n",
 			       (uintmax_t)strlen(obj_name), obj_name);
diff --git a/cache.h b/cache.h
index 49713cc5a5..70652e99dc 100644
--- a/cache.h
+++ b/cache.h
@@ -1332,6 +1332,24 @@ struct object_context {
 	GET_OID_TREE | GET_OID_TREEISH | \
 	GET_OID_BLOB)
 
+enum get_oid_result {
+	FOUND = 0,
+	MISSING_OBJECT = -1, /* The requested object is missing */
+	SHORT_NAME_AMBIGUOUS = -2,
+	/* The following only apply when symlinks are followed */
+	DANGLING_SYMLINK = -4, /*
+				* The initial symlink is there, but
+				* (transitively) points to a missing
+				* in-tree file
+				*/
+	SYMLINK_LOOP = -5,
+	NOT_DIR = -6, /*
+		       * Somewhere along the symlink chain, a path is
+		       * requested which contains a file as a
+		       * non-final element.
+		       */
+};
+
 extern int get_oid(const char *str, struct object_id *oid);
 extern int get_oid_commit(const char *str, struct object_id *oid);
 extern int get_oid_committish(const char *str, struct object_id *oid);
@@ -1339,7 +1357,7 @@ extern int get_oid_tree(const char *str, struct object_id *oid);
 extern int get_oid_treeish(const char *str, struct object_id *oid);
 extern int get_oid_blob(const char *str, struct object_id *oid);
 extern void maybe_die_on_misspelt_object_name(const char *name, const char *prefix);
-extern int get_oid_with_context(const char *str, unsigned flags, struct object_id *oid, struct object_context *oc);
+extern enum get_oid_result get_oid_with_context(const char *str, unsigned flags, struct object_id *oid, struct object_context *oc);
 
 
 typedef int each_abbrev_fn(const struct object_id *oid, void *);
diff --git a/sha1-name.c b/sha1-name.c
index b24502811b..12313165d0 100644
--- a/sha1-name.c
+++ b/sha1-name.c
@@ -190,9 +190,6 @@ static void find_short_packed_object(struct disambiguate_state *ds)
 		unique_in_pack(p, ds);
 }
 
-#define SHORT_NAME_NOT_FOUND (-1)
-#define SHORT_NAME_AMBIGUOUS (-2)
-
 static int finish_object_disambiguation(struct disambiguate_state *ds,
 					struct object_id *oid)
 {
@@ -200,7 +197,7 @@ static int finish_object_disambiguation(struct disambiguate_state *ds,
 		return SHORT_NAME_AMBIGUOUS;
 
 	if (!ds->candidate_exists)
-		return SHORT_NAME_NOT_FOUND;
+		return MISSING_OBJECT;
 
 	if (!ds->candidate_checked)
 		/*
@@ -414,8 +411,9 @@ static int sort_ambiguous(const void *a, const void *b)
 	return a_type_sort > b_type_sort ? 1 : -1;
 }
 
-static int get_short_oid(const char *name, int len, struct object_id *oid,
-			  unsigned flags)
+static enum get_oid_result get_short_oid(const char *name, int len,
+					 struct object_id *oid,
+					 unsigned flags)
 {
 	int status;
 	struct disambiguate_state ds;
@@ -733,7 +731,7 @@ static inline int push_mark(const char *string, int len)
 	return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
 }
 
-static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags);
+static enum get_oid_result get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags);
 static int interpret_nth_prior_checkout(const char *name, int namelen, struct strbuf *buf);
 
 static int get_oid_basic(const char *str, int len, struct object_id *oid,
@@ -883,11 +881,12 @@ static int get_oid_basic(const char *str, int len, struct object_id *oid,
 	return 0;
 }
 
-static int get_parent(const char *name, int len,
-		      struct object_id *result, int idx)
+static enum get_oid_result get_parent(const char *name, int len,
+				      struct object_id *result, int idx)
 {
 	struct object_id oid;
-	int ret = get_oid_1(name, len, &oid, GET_OID_COMMITTISH);
+	enum get_oid_result ret = get_oid_1(name, len, &oid,
+					    GET_OID_COMMITTISH);
 	struct commit *commit;
 	struct commit_list *p;
 
@@ -895,24 +894,25 @@ static int get_parent(const char *name, int len,
 		return ret;
 	commit = lookup_commit_reference(the_repository, &oid);
 	if (parse_commit(commit))
-		return -1;
+		return MISSING_OBJECT;
 	if (!idx) {
 		oidcpy(result, &commit->object.oid);
-		return 0;
+		return FOUND;
 	}
 	p = commit->parents;
 	while (p) {
 		if (!--idx) {
 			oidcpy(result, &p->item->object.oid);
-			return 0;
+			return FOUND;
 		}
 		p = p->next;
 	}
-	return -1;
+	return MISSING_OBJECT;
 }
 
-static int get_nth_ancestor(const char *name, int len,
-			    struct object_id *result, int generation)
+static enum get_oid_result get_nth_ancestor(const char *name, int len,
+					    struct object_id *result,
+					    int generation)
 {
 	struct object_id oid;
 	struct commit *commit;
@@ -923,15 +923,15 @@ static int get_nth_ancestor(const char *name, int len,
 		return ret;
 	commit = lookup_commit_reference(the_repository, &oid);
 	if (!commit)
-		return -1;
+		return MISSING_OBJECT;
 
 	while (generation--) {
 		if (parse_commit(commit) || !commit->parents)
-			return -1;
+			return MISSING_OBJECT;
 		commit = commit->parents->item;
 	}
 	oidcpy(result, &commit->object.oid);
-	return 0;
+	return FOUND;
 }
 
 struct object *peel_to_type(const char *name, int namelen,
@@ -1077,7 +1077,9 @@ static int get_describe_name(const char *name, int len, struct object_id *oid)
 	return -1;
 }
 
-static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags)
+static enum get_oid_result get_oid_1(const char *name, int len,
+				     struct object_id *oid,
+				     unsigned lookup_flags)
 {
 	int ret, has_suffix;
 	const char *cp;
@@ -1111,16 +1113,16 @@ static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned
 
 	ret = peel_onion(name, len, oid, lookup_flags);
 	if (!ret)
-		return 0;
+		return FOUND;
 
 	ret = get_oid_basic(name, len, oid, lookup_flags);
 	if (!ret)
-		return 0;
+		return FOUND;
 
 	/* It could be describe output that is "SOMETHING-gXXXX" */
 	ret = get_describe_name(name, len, oid);
 	if (!ret)
-		return 0;
+		return FOUND;
 
 	return get_short_oid(name, len, oid, lookup_flags);
 }
@@ -1664,11 +1666,11 @@ static char *resolve_relative_path(const char *rel)
 			   rel);
 }
 
-static int get_oid_with_context_1(const char *name,
-				  unsigned flags,
-				  const char *prefix,
-				  struct object_id *oid,
-				  struct object_context *oc)
+static enum get_oid_result get_oid_with_context_1(const char *name,
+						  unsigned flags,
+						  const char *prefix,
+						  struct object_id *oid,
+						  struct object_context *oc)
 {
 	int ret, bracket_depth;
 	int namelen = strlen(name);
diff --git a/tree-walk.c b/tree-walk.c
index 08210a4109..fb7959b21d 100644
--- a/tree-walk.c
+++ b/tree-walk.c
@@ -579,10 +579,10 @@ int get_tree_entry(const struct object_id *tree_oid, const char *name, struct ob
  * with the sha1 of the found object, and *mode will hold the mode of
  * the object.
  *
- * See the code for enum follow_symlink_result for a description of
+ * See the code for enum get_oid_result for a description of
  * the return values.
  */
-enum follow_symlinks_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode)
+enum get_oid_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode)
 {
 	int retval = MISSING_OBJECT;
 	struct dir_state *parents = NULL;
diff --git a/tree-walk.h b/tree-walk.h
index eefd26bb62..de6b95179d 100644
--- a/tree-walk.h
+++ b/tree-walk.h
@@ -51,23 +51,7 @@ struct traverse_info;
 typedef int (*traverse_callback_t)(int n, unsigned long mask, unsigned long dirmask, struct name_entry *entry, struct traverse_info *);
 int traverse_trees(struct index_state *istate, int n, struct tree_desc *t, struct traverse_info *info);
 
-enum follow_symlinks_result {
-	FOUND = 0, /* This includes out-of-tree links */
-	MISSING_OBJECT = -1, /* The initial symlink is missing */
-	DANGLING_SYMLINK = -2, /*
-				* The initial symlink is there, but
-				* (transitively) points to a missing
-				* in-tree file
-				*/
-	SYMLINK_LOOP = -3,
-	NOT_DIR = -4, /*
-		       * Somewhere along the symlink chain, a path is
-		       * requested which contains a file as a
-		       * non-final element.
-		       */
-};
-
-enum follow_symlinks_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode);
+enum get_oid_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode);
 
 struct traverse_info {
 	const char *traverse_path;
-- 
2.19.1

Re: cat-file ambiguity prints "dangling"

[Eric Wong]

David Turner <novalis@novalis.org> wrote:
> It appears that get_oid_with_context calls into get_short_oid for that
> case, and get_short_oid returns SHORT_NAME_AMBIGUOUS, which is -2.  We
> treat that as DANGLING_SYMLINK, which also seems to have the value -2. 
> So, it's an ambiguity in ambiguity resolution.
> 
> Fix attached.  

Thanks for the quick response.  Unfortunately, the patch makes
the situation worse for me...

> diff --git a/builtin/cat-file.c b/builtin/cat-file.c
> index 2ca56fd086..f2344b199f 100644
> --- a/builtin/cat-file.c
> +++ b/builtin/cat-file.c
> @@ -380,7 +380,7 @@ static void batch_one_object(const char *obj_name,
>  {
>  	struct object_context ctx;
>  	int flags = opt->follow_symlinks ? GET_OID_FOLLOW_SYMLINKS : 0;
> -	enum follow_symlinks_result result;
> +	enum get_oid_result result;
>  
>  	result = get_oid_with_context(obj_name, flags, &data->oid, &ctx);
>  	if (result != FOUND) {
> @@ -388,6 +388,9 @@ static void batch_one_object(const char *obj_name,
>  		case MISSING_OBJECT:
>  			printf("%s missing\n", obj_name);
>  			break;
> +		case SHORT_NAME_AMBIGUOUS:
> +			/* We've already printed the ambiguous message */
> +			break;

Because the message about ambiguity only goes to stderr.
Something needs to go to stdout, or else the reader process
would hang forever.

I've already updated my code[1] to work around "dangling",
but maybe printing "ambiguous" similar to the "missing" message
would be appropriate?  Something like:

		case SHORT_NAME_AMBIGUOUS:
			printf("%s ambiguous\n", obj_name);
			break;

(Along with a manpage update)


[1] new stuff for public-inbox on the way :>

Re: cat-file ambiguity prints "dangling"

[David Turner]

[-- Attachment #1: Type: text/plain, Size: 1839 bytes --]

Let's try this version.

On Fri, 2019-01-18 at 10:45 +0000, Eric Wong wrote:
> David Turner <novalis@novalis.org> wrote:
> > It appears that get_oid_with_context calls into get_short_oid for
> > that
> > case, and get_short_oid returns SHORT_NAME_AMBIGUOUS, which is
> > -2.  We
> > treat that as DANGLING_SYMLINK, which also seems to have the value
> > -2. 
> > So, it's an ambiguity in ambiguity resolution.
> > 
> > Fix attached.  
> 
> Thanks for the quick response.  Unfortunately, the patch makes
> the situation worse for me...
> 
> > diff --git a/builtin/cat-file.c b/builtin/cat-file.c
> > index 2ca56fd086..f2344b199f 100644
> > --- a/builtin/cat-file.c
> > +++ b/builtin/cat-file.c
> > @@ -380,7 +380,7 @@ static void batch_one_object(const char
> > *obj_name,
> >  {
> >  	struct object_context ctx;
> >  	int flags = opt->follow_symlinks ? GET_OID_FOLLOW_SYMLINKS : 0;
> > -	enum follow_symlinks_result result;
> > +	enum get_oid_result result;
> >  
> >  	result = get_oid_with_context(obj_name, flags, &data->oid,
> > &ctx);
> >  	if (result != FOUND) {
> > @@ -388,6 +388,9 @@ static void batch_one_object(const char
> > *obj_name,
> >  		case MISSING_OBJECT:
> >  			printf("%s missing\n", obj_name);
> >  			break;
> > +		case SHORT_NAME_AMBIGUOUS:
> > +			/* We've already printed the ambiguous message
> > */
> > +			break;
> 
> Because the message about ambiguity only goes to stderr.
> Something needs to go to stdout, or else the reader process
> would hang forever.
> 
> I've already updated my code[1] to work around "dangling",
> but maybe printing "ambiguous" similar to the "missing" message
> would be appropriate?  Something like:
> 
> 		case SHORT_NAME_AMBIGUOUS:
> 			printf("%s ambiguous\n", obj_name);
> 			break;
> 
> (Along with a manpage update)
> 
> 
> [1] new stuff for public-inbox on the way :>
> 

[-- Attachment #2: v2-0001-Do-not-print-dangling-for-cat-file-in-case-of-amb.patch --]
[-- Type: text/x-patch, Size: 11078 bytes --]

From b152b3463477a8260d2b8c0ab46ad76562feed37 Mon Sep 17 00:00:00 2001
From: David Turner <novalis@novalis.org>
Date: Thu, 17 Jan 2019 23:19:43 -0500
Subject: [PATCH v2] Do not print 'dangling' for cat-file in case of ambiguity

The return values -1 and -2 from get_oid could mean two different
things, depending on whether they were from an enum returned by
get_tree_entry_follow_symlinks, or from a different code path.  This
caused 'dangling' to be printed from a git cat-file in the case of an
ambiguous (-2) result.

Unify the results of get_oid* and get_tree_entry_follow_symlinks to be
one common type, with unambiguous values.

Signed-off-by: David Turner <novalis@novalis.org>
Reported-by: Eric Wong <e@80x24.org>
---
 Documentation/git-cat-file.txt |  6 ++++
 builtin/cat-file.c             |  5 ++-
 cache.h                        | 20 +++++++++++-
 sha1-name.c                    | 58 ++++++++++++++++++----------------
 tree-walk.c                    |  4 +--
 tree-walk.h                    | 18 +----------
 6 files changed, 62 insertions(+), 49 deletions(-)

diff --git a/Documentation/git-cat-file.txt b/Documentation/git-cat-file.txt
index 74013335a1..e27a940985 100644
--- a/Documentation/git-cat-file.txt
+++ b/Documentation/git-cat-file.txt
@@ -252,6 +252,12 @@ the repository, then `cat-file` will ignore any custom format and print:
 <object> SP missing LF
 ------------
 
+If a name is specified that might refer to more than one object (an ambiguous short sha), then `cat-file` will ignore any custom format and print:
+
+------------
+<object> SP ambiguous LF
+------------
+
 If --follow-symlinks is used, and a symlink in the repository points
 outside the repository, then `cat-file` will ignore any custom format
 and print:
diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index 2ca56fd086..cebc6d7f8a 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -380,7 +380,7 @@ static void batch_one_object(const char *obj_name,
 {
 	struct object_context ctx;
 	int flags = opt->follow_symlinks ? GET_OID_FOLLOW_SYMLINKS : 0;
-	enum follow_symlinks_result result;
+	enum get_oid_result result;
 
 	result = get_oid_with_context(obj_name, flags, &data->oid, &ctx);
 	if (result != FOUND) {
@@ -388,6 +388,9 @@ static void batch_one_object(const char *obj_name,
 		case MISSING_OBJECT:
 			printf("%s missing\n", obj_name);
 			break;
+		case SHORT_NAME_AMBIGUOUS:
+			printf("%s ambiguous\n", obj_name);
+			break;
 		case DANGLING_SYMLINK:
 			printf("dangling %"PRIuMAX"\n%s\n",
 			       (uintmax_t)strlen(obj_name), obj_name);
diff --git a/cache.h b/cache.h
index 49713cc5a5..70652e99dc 100644
--- a/cache.h
+++ b/cache.h
@@ -1332,6 +1332,24 @@ struct object_context {
 	GET_OID_TREE | GET_OID_TREEISH | \
 	GET_OID_BLOB)
 
+enum get_oid_result {
+	FOUND = 0,
+	MISSING_OBJECT = -1, /* The requested object is missing */
+	SHORT_NAME_AMBIGUOUS = -2,
+	/* The following only apply when symlinks are followed */
+	DANGLING_SYMLINK = -4, /*
+				* The initial symlink is there, but
+				* (transitively) points to a missing
+				* in-tree file
+				*/
+	SYMLINK_LOOP = -5,
+	NOT_DIR = -6, /*
+		       * Somewhere along the symlink chain, a path is
+		       * requested which contains a file as a
+		       * non-final element.
+		       */
+};
+
 extern int get_oid(const char *str, struct object_id *oid);
 extern int get_oid_commit(const char *str, struct object_id *oid);
 extern int get_oid_committish(const char *str, struct object_id *oid);
@@ -1339,7 +1357,7 @@ extern int get_oid_tree(const char *str, struct object_id *oid);
 extern int get_oid_treeish(const char *str, struct object_id *oid);
 extern int get_oid_blob(const char *str, struct object_id *oid);
 extern void maybe_die_on_misspelt_object_name(const char *name, const char *prefix);
-extern int get_oid_with_context(const char *str, unsigned flags, struct object_id *oid, struct object_context *oc);
+extern enum get_oid_result get_oid_with_context(const char *str, unsigned flags, struct object_id *oid, struct object_context *oc);
 
 
 typedef int each_abbrev_fn(const struct object_id *oid, void *);
diff --git a/sha1-name.c b/sha1-name.c
index b24502811b..12313165d0 100644
--- a/sha1-name.c
+++ b/sha1-name.c
@@ -190,9 +190,6 @@ static void find_short_packed_object(struct disambiguate_state *ds)
 		unique_in_pack(p, ds);
 }
 
-#define SHORT_NAME_NOT_FOUND (-1)
-#define SHORT_NAME_AMBIGUOUS (-2)
-
 static int finish_object_disambiguation(struct disambiguate_state *ds,
 					struct object_id *oid)
 {
@@ -200,7 +197,7 @@ static int finish_object_disambiguation(struct disambiguate_state *ds,
 		return SHORT_NAME_AMBIGUOUS;
 
 	if (!ds->candidate_exists)
-		return SHORT_NAME_NOT_FOUND;
+		return MISSING_OBJECT;
 
 	if (!ds->candidate_checked)
 		/*
@@ -414,8 +411,9 @@ static int sort_ambiguous(const void *a, const void *b)
 	return a_type_sort > b_type_sort ? 1 : -1;
 }
 
-static int get_short_oid(const char *name, int len, struct object_id *oid,
-			  unsigned flags)
+static enum get_oid_result get_short_oid(const char *name, int len,
+					 struct object_id *oid,
+					 unsigned flags)
 {
 	int status;
 	struct disambiguate_state ds;
@@ -733,7 +731,7 @@ static inline int push_mark(const char *string, int len)
 	return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
 }
 
-static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags);
+static enum get_oid_result get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags);
 static int interpret_nth_prior_checkout(const char *name, int namelen, struct strbuf *buf);
 
 static int get_oid_basic(const char *str, int len, struct object_id *oid,
@@ -883,11 +881,12 @@ static int get_oid_basic(const char *str, int len, struct object_id *oid,
 	return 0;
 }
 
-static int get_parent(const char *name, int len,
-		      struct object_id *result, int idx)
+static enum get_oid_result get_parent(const char *name, int len,
+				      struct object_id *result, int idx)
 {
 	struct object_id oid;
-	int ret = get_oid_1(name, len, &oid, GET_OID_COMMITTISH);
+	enum get_oid_result ret = get_oid_1(name, len, &oid,
+					    GET_OID_COMMITTISH);
 	struct commit *commit;
 	struct commit_list *p;
 
@@ -895,24 +894,25 @@ static int get_parent(const char *name, int len,
 		return ret;
 	commit = lookup_commit_reference(the_repository, &oid);
 	if (parse_commit(commit))
-		return -1;
+		return MISSING_OBJECT;
 	if (!idx) {
 		oidcpy(result, &commit->object.oid);
-		return 0;
+		return FOUND;
 	}
 	p = commit->parents;
 	while (p) {
 		if (!--idx) {
 			oidcpy(result, &p->item->object.oid);
-			return 0;
+			return FOUND;
 		}
 		p = p->next;
 	}
-	return -1;
+	return MISSING_OBJECT;
 }
 
-static int get_nth_ancestor(const char *name, int len,
-			    struct object_id *result, int generation)
+static enum get_oid_result get_nth_ancestor(const char *name, int len,
+					    struct object_id *result,
+					    int generation)
 {
 	struct object_id oid;
 	struct commit *commit;
@@ -923,15 +923,15 @@ static int get_nth_ancestor(const char *name, int len,
 		return ret;
 	commit = lookup_commit_reference(the_repository, &oid);
 	if (!commit)
-		return -1;
+		return MISSING_OBJECT;
 
 	while (generation--) {
 		if (parse_commit(commit) || !commit->parents)
-			return -1;
+			return MISSING_OBJECT;
 		commit = commit->parents->item;
 	}
 	oidcpy(result, &commit->object.oid);
-	return 0;
+	return FOUND;
 }
 
 struct object *peel_to_type(const char *name, int namelen,
@@ -1077,7 +1077,9 @@ static int get_describe_name(const char *name, int len, struct object_id *oid)
 	return -1;
 }
 
-static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags)
+static enum get_oid_result get_oid_1(const char *name, int len,
+				     struct object_id *oid,
+				     unsigned lookup_flags)
 {
 	int ret, has_suffix;
 	const char *cp;
@@ -1111,16 +1113,16 @@ static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned
 
 	ret = peel_onion(name, len, oid, lookup_flags);
 	if (!ret)
-		return 0;
+		return FOUND;
 
 	ret = get_oid_basic(name, len, oid, lookup_flags);
 	if (!ret)
-		return 0;
+		return FOUND;
 
 	/* It could be describe output that is "SOMETHING-gXXXX" */
 	ret = get_describe_name(name, len, oid);
 	if (!ret)
-		return 0;
+		return FOUND;
 
 	return get_short_oid(name, len, oid, lookup_flags);
 }
@@ -1664,11 +1666,11 @@ static char *resolve_relative_path(const char *rel)
 			   rel);
 }
 
-static int get_oid_with_context_1(const char *name,
-				  unsigned flags,
-				  const char *prefix,
-				  struct object_id *oid,
-				  struct object_context *oc)
+static enum get_oid_result get_oid_with_context_1(const char *name,
+						  unsigned flags,
+						  const char *prefix,
+						  struct object_id *oid,
+						  struct object_context *oc)
 {
 	int ret, bracket_depth;
 	int namelen = strlen(name);
diff --git a/tree-walk.c b/tree-walk.c
index 08210a4109..fb7959b21d 100644
--- a/tree-walk.c
+++ b/tree-walk.c
@@ -579,10 +579,10 @@ int get_tree_entry(const struct object_id *tree_oid, const char *name, struct ob
  * with the sha1 of the found object, and *mode will hold the mode of
  * the object.
  *
- * See the code for enum follow_symlink_result for a description of
+ * See the code for enum get_oid_result for a description of
  * the return values.
  */
-enum follow_symlinks_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode)
+enum get_oid_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode)
 {
 	int retval = MISSING_OBJECT;
 	struct dir_state *parents = NULL;
diff --git a/tree-walk.h b/tree-walk.h
index eefd26bb62..de6b95179d 100644
--- a/tree-walk.h
+++ b/tree-walk.h
@@ -51,23 +51,7 @@ struct traverse_info;
 typedef int (*traverse_callback_t)(int n, unsigned long mask, unsigned long dirmask, struct name_entry *entry, struct traverse_info *);
 int traverse_trees(struct index_state *istate, int n, struct tree_desc *t, struct traverse_info *info);
 
-enum follow_symlinks_result {
-	FOUND = 0, /* This includes out-of-tree links */
-	MISSING_OBJECT = -1, /* The initial symlink is missing */
-	DANGLING_SYMLINK = -2, /*
-				* The initial symlink is there, but
-				* (transitively) points to a missing
-				* in-tree file
-				*/
-	SYMLINK_LOOP = -3,
-	NOT_DIR = -4, /*
-		       * Somewhere along the symlink chain, a path is
-		       * requested which contains a file as a
-		       * non-final element.
-		       */
-};
-
-enum follow_symlinks_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode);
+enum get_oid_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode);
 
 struct traverse_info {
 	const char *traverse_path;
-- 
2.19.1

[PATCH] t1512: test ambiguous cat-file --batch and --batch-output

[Eric Wong]

David Turner <novalis@novalis.org> wrote:
> Let's try this version.

Thanks!

Tested-by: Eric Wong <e@80x24.org>

Not sure if t1512 would be the best place to put the test, but
having a repo with ambiguous data already at hand was easiest.

---------8<-------
Subject: [PATCH] t1512: test ambiguous cat-file --batch and --batch-output

Test the new "ambiguous" result from cat-file --batch and
--batch-check.  This is in t1512 instead of t1006 since
we need a repo with ambiguous object_id names.

Signed-off-by: Eric Wong <e@80x24.org>
---
 t/t1512-rev-parse-disambiguation.sh | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/t/t1512-rev-parse-disambiguation.sh b/t/t1512-rev-parse-disambiguation.sh
index e4d5b56014..b0819630c9 100755
--- a/t/t1512-rev-parse-disambiguation.sh
+++ b/t/t1512-rev-parse-disambiguation.sh
@@ -388,4 +388,14 @@ test_expect_success C_LOCALE_OUTPUT 'ambiguous commits are printed by type first
 	done
 '
 
+test_expect_success 'cat-file --batch and --batch-check show ambiguous' '
+	echo "0000 ambiguous" >expect &&
+	echo 0000 | git cat-file --batch-check >actual 2>err &&
+	test_cmp expect actual &&
+	grep hint: err &&
+	echo 0000 | git cat-file --batch >actual 2>err &&
+	test_cmp expect actual &&
+	grep hint: err
+'
+
 test_done
-- 
EW

Re: [PATCH] t1512: test ambiguous cat-file --batch and --batch-output

[David Turner]

Thanks for adding the test. 

On Fri, 2019-01-18 at 22:26 +0000, Eric Wong wrote:
> David Turner <novalis@novalis.org> wrote:
> > Let's try this version.
> 
> Thanks!
> 
> Tested-by: Eric Wong <e@80x24.org>
> 
> Not sure if t1512 would be the best place to put the test, but
> having a repo with ambiguous data already at hand was easiest.
> 
> ---------8<-------
> Subject: [PATCH] t1512: test ambiguous cat-file --batch and --batch-
> output
> 
> Test the new "ambiguous" result from cat-file --batch and
> --batch-check.  This is in t1512 instead of t1006 since
> we need a repo with ambiguous object_id names.
> 
> Signed-off-by: Eric Wong <e@80x24.org>
> ---
>  t/t1512-rev-parse-disambiguation.sh | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/t/t1512-rev-parse-disambiguation.sh b/t/t1512-rev-parse-
> disambiguation.sh
> index e4d5b56014..b0819630c9 100755
> --- a/t/t1512-rev-parse-disambiguation.sh
> +++ b/t/t1512-rev-parse-disambiguation.sh
> @@ -388,4 +388,14 @@ test_expect_success C_LOCALE_OUTPUT 'ambiguous
> commits are printed by type first
>  	done
>  '
>  
> +test_expect_success 'cat-file --batch and --batch-check show
> ambiguous' '
> +	echo "0000 ambiguous" >expect &&
> +	echo 0000 | git cat-file --batch-check >actual 2>err &&
> +	test_cmp expect actual &&
> +	grep hint: err &&
> +	echo 0000 | git cat-file --batch >actual 2>err &&
> +	test_cmp expect actual &&
> +	grep hint: err
> +'
> +
>  test_done

Re: [PATCH] t1512: test ambiguous cat-file --batch and --batch-output

[SZEDER Gábor]

On Fri, Jan 18, 2019 at 10:26:29PM +0000, Eric Wong wrote:
> Test the new "ambiguous" result from cat-file --batch and
> --batch-check.  This is in t1512 instead of t1006 since
> we need a repo with ambiguous object_id names.
> 
> Signed-off-by: Eric Wong <e@80x24.org>
> ---
>  t/t1512-rev-parse-disambiguation.sh | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/t/t1512-rev-parse-disambiguation.sh b/t/t1512-rev-parse-disambiguation.sh
> index e4d5b56014..b0819630c9 100755
> --- a/t/t1512-rev-parse-disambiguation.sh
> +++ b/t/t1512-rev-parse-disambiguation.sh
> @@ -388,4 +388,14 @@ test_expect_success C_LOCALE_OUTPUT 'ambiguous commits are printed by type first
>  	done
>  '
>  
> +test_expect_success 'cat-file --batch and --batch-check show ambiguous' '
> +	echo "0000 ambiguous" >expect &&
> +	echo 0000 | git cat-file --batch-check >actual 2>err &&
> +	test_cmp expect actual &&
> +	grep hint: err &&
> +	echo 0000 | git cat-file --batch >actual 2>err &&
> +	test_cmp expect actual &&
> +	grep hint: err

The 'git cat-file's error message and hints are translated, so they
should be checked by 'test_i18ngrep' instead of plain old grep.

> +'
> +
>  test_done
> -- 
> EW

[PATCH v2] t1512: test ambiguous cat-file --batch and --batch-output

[Eric Wong]

SZEDER Gábor <szeder.dev@gmail.com> wrote:
> The 'git cat-file's error message and hints are translated, so they
> should be checked by 'test_i18ngrep' instead of plain old grep.

Thanks, here's v2 with test_i18ngrep

--------8<------
Subject: [PATCH] t1512: test ambiguous cat-file --batch and --batch-output

Test the new "ambiguous" result from cat-file --batch and
--batch-check.  This is in t1512 instead of t1006 since
we need a repo with ambiguous object_id names.

Signed-off-by: Eric Wong <e@80x24.org>
---
 t/t1512-rev-parse-disambiguation.sh | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/t/t1512-rev-parse-disambiguation.sh b/t/t1512-rev-parse-disambiguation.sh
index e4d5b56014..c19fb500cb 100755
--- a/t/t1512-rev-parse-disambiguation.sh
+++ b/t/t1512-rev-parse-disambiguation.sh
@@ -388,4 +388,14 @@ test_expect_success C_LOCALE_OUTPUT 'ambiguous commits are printed by type first
 	done
 '
 
+test_expect_success 'cat-file --batch and --batch-check show ambiguous' '
+	echo "0000 ambiguous" >expect &&
+	echo 0000 | git cat-file --batch-check >actual 2>err &&
+	test_cmp expect actual &&
+	test_i18ngrep hint: err &&
+	echo 0000 | git cat-file --batch >actual 2>err &&
+	test_cmp expect actual &&
+	test_i18ngrep hint: err
+'
+
 test_done
-- 
EW