Merge branch 'jk/interpret-branch-name'

"git branch @" created refs/heads/@ as a branch, and in general the
code that handled @{-1} and @{upstream} was a bit too loose in
disambiguating.

* jk/interpret-branch-name:
  checkout: restrict @-expansions when finding branch
  strbuf_check_ref_format(): expand only local branches
  branch: restrict @-expansions when deleting
  t3204: test git-branch @-expansion corner cases
  interpret_branch_name: allow callers to restrict expansions
  strbuf_branchname: add docstring
  strbuf_branchname: drop return value
  interpret_branch_name: move docstring to header file
  interpret_branch_name(): handle auto-namelen for @{-1}
This commit is contained in:
Junio C Hamano 2017-03-14 15:23:18 -07:00
commit c809496c97
10 changed files with 249 additions and 51 deletions

View File

@ -191,17 +191,20 @@ static int delete_branches(int argc, const char **argv, int force, int kinds,
int ret = 0;
int remote_branch = 0;
struct strbuf bname = STRBUF_INIT;
unsigned allowed_interpret;
switch (kinds) {
case FILTER_REFS_REMOTES:
fmt = "refs/remotes/%s";
/* For subsequent UI messages */
remote_branch = 1;
allowed_interpret = INTERPRET_BRANCH_REMOTE;
force = 1;
break;
case FILTER_REFS_BRANCHES:
fmt = "refs/heads/%s";
allowed_interpret = INTERPRET_BRANCH_LOCAL;
break;
default:
die(_("cannot use -a with -d"));
@ -216,7 +219,7 @@ static int delete_branches(int argc, const char **argv, int force, int kinds,
char *target = NULL;
int flags = 0;
strbuf_branchname(&bname, argv[i]);
strbuf_branchname(&bname, argv[i], allowed_interpret);
free(name);
name = mkpathdup(fmt, bname.buf);

View File

@ -452,7 +452,7 @@ static void setup_branch_path(struct branch_info *branch)
{
struct strbuf buf = STRBUF_INIT;
strbuf_branchname(&buf, branch->name);
strbuf_branchname(&buf, branch->name, INTERPRET_BRANCH_LOCAL);
if (strcmp(buf.buf, branch->name))
branch->name = xstrdup(buf.buf);
strbuf_splice(&buf, 0, 0, "refs/heads/", 11);

View File

@ -438,7 +438,7 @@ static void merge_name(const char *remote, struct strbuf *msg)
char *found_ref;
int len, early;
strbuf_branchname(&bname, remote);
strbuf_branchname(&bname, remote, 0);
remote = bname.buf;
memset(branch_head, 0, sizeof(branch_head));

32
cache.h
View File

@ -1360,7 +1360,37 @@ extern char *oid_to_hex_r(char *out, const struct object_id *oid);
extern char *sha1_to_hex(const unsigned char *sha1); /* static buffer result! */
extern char *oid_to_hex(const struct object_id *oid); /* same static buffer as sha1_to_hex */
extern int interpret_branch_name(const char *str, int len, struct strbuf *);
/*
* This reads short-hand syntax that not only evaluates to a commit
* object name, but also can act as if the end user spelled the name
* of the branch from the command line.
*
* - "@{-N}" finds the name of the Nth previous branch we were on, and
* places the name of the branch in the given buf and returns the
* number of characters parsed if successful.
*
* - "<branch>@{upstream}" finds the name of the other ref that
* <branch> is configured to merge with (missing <branch> defaults
* to the current branch), and places the name of the branch in the
* given buf and returns the number of characters parsed if
* successful.
*
* If the input is not of the accepted format, it returns a negative
* number to signal an error.
*
* If the input was ok but there are not N branch switches in the
* reflog, it returns 0.
*
* If "allowed" is non-zero, it is a treated as a bitfield of allowable
* expansions: local branches ("refs/heads/"), remote branches
* ("refs/remotes/"), or "HEAD". If no "allowed" bits are set, any expansion is
* allowed, even ones to refs outside of those namespaces.
*/
#define INTERPRET_BRANCH_LOCAL (1<<0)
#define INTERPRET_BRANCH_REMOTE (1<<1)
#define INTERPRET_BRANCH_HEAD (1<<2)
extern int interpret_branch_name(const char *str, int len, struct strbuf *,
unsigned allowed);
extern int get_oid_mb(const char *str, struct object_id *oid);
extern int validate_headref(const char *ref);

2
refs.c
View File

@ -405,7 +405,7 @@ int refname_match(const char *abbrev_name, const char *full_name)
static char *substitute_branch_name(const char **string, int *len)
{
struct strbuf buf = STRBUF_INIT;
int ret = interpret_branch_name(*string, *len, &buf);
int ret = interpret_branch_name(*string, *len, &buf, 0);
if (ret == *len) {
size_t size;

View File

@ -147,7 +147,7 @@ static void add_pending_object_with_path(struct rev_info *revs,
revs->no_walk = 0;
if (revs->reflog_info && obj->type == OBJ_COMMIT) {
struct strbuf buf = STRBUF_INIT;
int len = interpret_branch_name(name, 0, &buf);
int len = interpret_branch_name(name, 0, &buf, 0);
int st;
if (0 < len && name[len] && buf.len)

View File

@ -1176,7 +1176,8 @@ static int interpret_empty_at(const char *name, int namelen, int len, struct str
return 1;
}
static int reinterpret(const char *name, int namelen, int len, struct strbuf *buf)
static int reinterpret(const char *name, int namelen, int len,
struct strbuf *buf, unsigned allowed)
{
/* we have extra data, which might need further processing */
struct strbuf tmp = STRBUF_INIT;
@ -1184,7 +1185,7 @@ static int reinterpret(const char *name, int namelen, int len, struct strbuf *bu
int ret;
strbuf_add(buf, name + len, namelen - len);
ret = interpret_branch_name(buf->buf, buf->len, &tmp);
ret = interpret_branch_name(buf->buf, buf->len, &tmp, allowed);
/* that data was not interpreted, remove our cruft */
if (ret < 0) {
strbuf_setlen(buf, used);
@ -1205,11 +1206,27 @@ static void set_shortened_ref(struct strbuf *buf, const char *ref)
free(s);
}
static int branch_interpret_allowed(const char *refname, unsigned allowed)
{
if (!allowed)
return 1;
if ((allowed & INTERPRET_BRANCH_LOCAL) &&
starts_with(refname, "refs/heads/"))
return 1;
if ((allowed & INTERPRET_BRANCH_REMOTE) &&
starts_with(refname, "refs/remotes/"))
return 1;
return 0;
}
static int interpret_branch_mark(const char *name, int namelen,
int at, struct strbuf *buf,
int (*get_mark)(const char *, int),
const char *(*get_data)(struct branch *,
struct strbuf *))
struct strbuf *),
unsigned allowed)
{
int len;
struct branch *branch;
@ -1234,64 +1251,55 @@ static int interpret_branch_mark(const char *name, int namelen,
if (!value)
die("%s", err.buf);
if (!branch_interpret_allowed(value, allowed))
return -1;
set_shortened_ref(buf, value);
return len + at;
}
/*
* This reads short-hand syntax that not only evaluates to a commit
* object name, but also can act as if the end user spelled the name
* of the branch from the command line.
*
* - "@{-N}" finds the name of the Nth previous branch we were on, and
* places the name of the branch in the given buf and returns the
* number of characters parsed if successful.
*
* - "<branch>@{upstream}" finds the name of the other ref that
* <branch> is configured to merge with (missing <branch> defaults
* to the current branch), and places the name of the branch in the
* given buf and returns the number of characters parsed if
* successful.
*
* If the input is not of the accepted format, it returns a negative
* number to signal an error.
*
* If the input was ok but there are not N branch switches in the
* reflog, it returns 0.
*/
int interpret_branch_name(const char *name, int namelen, struct strbuf *buf)
int interpret_branch_name(const char *name, int namelen, struct strbuf *buf,
unsigned allowed)
{
char *at;
const char *start;
int len = interpret_nth_prior_checkout(name, namelen, buf);
int len;
if (!namelen)
namelen = strlen(name);
if (!allowed || (allowed & INTERPRET_BRANCH_LOCAL)) {
len = interpret_nth_prior_checkout(name, namelen, buf);
if (!len) {
return len; /* syntax Ok, not enough switches */
} else if (len > 0) {
if (len == namelen)
return len; /* consumed all */
else
return reinterpret(name, namelen, len, buf);
return reinterpret(name, namelen, len, buf, allowed);
}
}
for (start = name;
(at = memchr(start, '@', namelen - (start - name)));
start = at + 1) {
if (!allowed || (allowed & INTERPRET_BRANCH_HEAD)) {
len = interpret_empty_at(name, namelen, at - name, buf);
if (len > 0)
return reinterpret(name, namelen, len, buf);
return reinterpret(name, namelen, len, buf,
allowed);
}
len = interpret_branch_mark(name, namelen, at - name, buf,
upstream_mark, branch_get_upstream);
upstream_mark, branch_get_upstream,
allowed);
if (len > 0)
return len;
len = interpret_branch_mark(name, namelen, at - name, buf,
push_mark, branch_get_push);
push_mark, branch_get_push,
allowed);
if (len > 0)
return len;
}
@ -1299,22 +1307,19 @@ int interpret_branch_name(const char *name, int namelen, struct strbuf *buf)
return -1;
}
int strbuf_branchname(struct strbuf *sb, const char *name)
void strbuf_branchname(struct strbuf *sb, const char *name, unsigned allowed)
{
int len = strlen(name);
int used = interpret_branch_name(name, len, sb);
int used = interpret_branch_name(name, len, sb, allowed);
if (used == len)
return 0;
if (used < 0)
used = 0;
strbuf_add(sb, name + used, len - used);
return len;
}
int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
{
strbuf_branchname(sb, name);
strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);
if (name[0] == '-')
return -1;
strbuf_splice(sb, 0, 0, "refs/heads/", 11);

View File

@ -574,7 +574,26 @@ static inline void strbuf_complete_line(struct strbuf *sb)
strbuf_complete(sb, '\n');
}
extern int strbuf_branchname(struct strbuf *sb, const char *name);
/*
* Copy "name" to "sb", expanding any special @-marks as handled by
* interpret_branch_name(). The result is a non-qualified branch name
* (so "foo" or "origin/master" instead of "refs/heads/foo" or
* "refs/remotes/origin/master").
*
* Note that the resulting name may not be a syntactically valid refname.
*
* If "allowed" is non-zero, restrict the set of allowed expansions. See
* interpret_branch_name() for details.
*/
extern void strbuf_branchname(struct strbuf *sb, const char *name,
unsigned allowed);
/*
* Like strbuf_branchname() above, but confirm that the result is
* syntactically valid to be used as a local branch name in refs/heads/.
*
* The return value is "0" if the result is valid, and "-1" otherwise.
*/
extern int strbuf_check_branch_ref(struct strbuf *sb, const char *name);
extern void strbuf_addstr_urlencode(struct strbuf *, const char *,

View File

@ -56,5 +56,13 @@ test_expect_success 'merge @{-100} before checking out that many branches yet' '
test_must_fail git merge @{-100}
'
test_expect_success 'log -g @{-1}' '
git checkout -b last_branch &&
git checkout -b new_branch &&
echo "last_branch@{0}" >expect &&
git log -g --format=%gd @{-1} >actual &&
test_cmp expect actual
'
test_done

View File

@ -0,0 +1,133 @@
#!/bin/sh
test_description='interpreting exotic branch name arguments
Branch name arguments are usually names which are taken to be inside of
refs/heads/, but we interpret some magic syntax like @{-1}, @{upstream}, etc.
This script aims to check the behavior of those corner cases.
'
. ./test-lib.sh
expect_branch() {
git log -1 --format=%s "$1" >actual &&
echo "$2" >expect &&
test_cmp expect actual
}
expect_deleted() {
test_must_fail git rev-parse --verify "$1"
}
test_expect_success 'set up repo' '
test_commit one &&
test_commit two &&
git remote add origin foo.git
'
test_expect_success 'update branch via @{-1}' '
git branch previous one &&
git checkout previous &&
git checkout master &&
git branch -f @{-1} two &&
expect_branch previous two
'
test_expect_success 'update branch via local @{upstream}' '
git branch local one &&
git branch --set-upstream-to=local &&
git branch -f @{upstream} two &&
expect_branch local two
'
test_expect_success 'disallow updating branch via remote @{upstream}' '
git update-ref refs/remotes/origin/remote one &&
git branch --set-upstream-to=origin/remote &&
test_must_fail git branch -f @{upstream} two
'
test_expect_success 'create branch with pseudo-qualified name' '
git branch refs/heads/qualified two &&
expect_branch refs/heads/refs/heads/qualified two
'
test_expect_success 'delete branch via @{-1}' '
git branch previous-del &&
git checkout previous-del &&
git checkout master &&
git branch -D @{-1} &&
expect_deleted previous-del
'
test_expect_success 'delete branch via local @{upstream}' '
git branch local-del &&
git branch --set-upstream-to=local-del &&
git branch -D @{upstream} &&
expect_deleted local-del
'
test_expect_success 'delete branch via remote @{upstream}' '
git update-ref refs/remotes/origin/remote-del two &&
git branch --set-upstream-to=origin/remote-del &&
git branch -r -D @{upstream} &&
expect_deleted origin/remote-del
'
# Note that we create two oddly named local branches here. We want to make
# sure that we do not accidentally delete either of them, even if
# shorten_unambiguous_ref() tweaks the name to avoid ambiguity.
test_expect_success 'delete @{upstream} expansion matches -r option' '
git update-ref refs/remotes/origin/remote-del two &&
git branch --set-upstream-to=origin/remote-del &&
git update-ref refs/heads/origin/remote-del two &&
git update-ref refs/heads/remotes/origin/remote-del two &&
test_must_fail git branch -D @{upstream} &&
expect_branch refs/heads/origin/remote-del two &&
expect_branch refs/heads/remotes/origin/remote-del two
'
test_expect_success 'disallow deleting remote branch via @{-1}' '
git update-ref refs/remotes/origin/previous one &&
git checkout -b origin/previous two &&
git checkout master &&
test_must_fail git branch -r -D @{-1} &&
expect_branch refs/remotes/origin/previous one &&
expect_branch refs/heads/origin/previous two
'
# The thing we are testing here is that "@" is the real branch refs/heads/@,
# and not refs/heads/HEAD. These tests should not imply that refs/heads/@ is a
# sane thing, but it _is_ technically allowed for now. If we disallow it, these
# can be switched to test_must_fail.
test_expect_success 'create branch named "@"' '
git branch -f @ one &&
expect_branch refs/heads/@ one
'
test_expect_success 'delete branch named "@"' '
git update-ref refs/heads/@ two &&
git branch -D @ &&
expect_deleted refs/heads/@
'
test_expect_success 'checkout does not treat remote @{upstream} as a branch' '
git update-ref refs/remotes/origin/checkout one &&
git branch --set-upstream-to=origin/checkout &&
git update-ref refs/heads/origin/checkout two &&
git update-ref refs/heads/remotes/origin/checkout two &&
git checkout @{upstream} &&
expect_branch HEAD one
'
test_done