@matheusbsbs / matheus-bagliano / commits / 7c3f847aad

check-ref-format --branch: do not expand @{...} outside repository

Running "git check-ref-format --branch @{-1}" from outside any repository produces $ git check-ref-format --branch @{-1} BUG: environment.c:182: git environment hasn't been setup This is because the expansion of @{-1} must come from the HEAD reflog, which involves opening the repository. @{u} and @{push} (which are more unusual because they typically would not expand to a local branch) trigger the same assertion. This has been broken since day one. Before v2.13.0-rc0~48^2 (setup_git_env: avoid blind fall-back to ".git", 2016-10-02), the breakage was more subtle: Git would read reflogs from ".git" within the current directory even if it was not a valid repository. Usually that is harmless because Git is not being run from the root directory of an invalid repository, but in edge cases such accesses can be confusing or harmful. Since v2.13.0, the problem is easier to diagnose because Git aborts with a BUG message. Erroring out is the right behavior: when asked to interpret a branch name like "@{-1}", there is no reasonable answer in this context. But we should print a message saying so instead of an assertion failure. We do not forbid "check-ref-format --branch" from outside a repository altogether because it is ok for a script to pre-process branch arguments without @{...} in such a context. For example, with pre-2.13 Git, a script that does branch='master'; # default value parse_options branch=$(git check-ref-format --branch "$branch") to normalize an optional branch name provided by the user would work both inside a repository (where the user could provide '@{-1}') and outside (where '@{-1}' should not be accepted). So disable the "expand @{...}" half of the feature when run outside a repository, but keep the check of the syntax of a proposed branch name. This way, when run from outside a repository, "git check-ref-format --branch @{-1}" will gracefully fail: $ git check-ref-format --branch @{-1} fatal: '@{-1}' is not a valid branch name and "git check-ref-format --branch master" will succeed as before: $ git check-ref-format --branch master master restoring the usual pre-2.13 behavior. [jn: split out from a larger patch; moved conditional to strbuf_check_branch_ref instead of its caller; fleshed out commit message; some style tweaks in tests] Reported-by: Marko Kungla <marko.kungla@gmail.com> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Junio C Hamano committed Oct 17, 2017 at 00:08 UTC 7c3f847aad79f847e3b786e1bb56361af3f61a69

2 files changed +20 -1

sha1_name.c

+4 -1

@@ -1321,7 +1321,10 @@ void strbuf_branchname(struct strbuf *sb, const char *name, unsigned allowed)

1321

1322 int strbuf_check_branch_ref(struct strbuf *sb, const char *name)

1323 {

1324 - strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);

1324 + if (startup_info->have_repository)

1325 + strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);

1326 + else

1327 + strbuf_addstr(sb, name);

1328 if (name[0] == '-')

1329 return -1;

1330 strbuf_splice(sb, 0, 0, "refs/heads/", 11);

t/t1402-check-ref-format.sh

+16

@@ -144,6 +144,11 @@ test_expect_success "check-ref-format --branch @{-1}" '

144 refname2=$(git check-ref-format --branch @{-2}) &&

145 test "$refname2" = master'

146

147 +test_expect_success 'check-ref-format --branch -naster' '

148 + test_must_fail git check-ref-format --branch -naster >actual &&

149 + test_must_be_empty actual

150 +'

151 +

152 test_expect_success 'check-ref-format --branch from subdir' '

153 mkdir subdir &&

154

@@ -161,6 +166,17 @@ test_expect_success 'check-ref-format --branch from subdir' '

166 test "$refname" = "$sha1"

167 '

168

169 +test_expect_success 'check-ref-format --branch @{-1} from non-repo' '

170 + nongit test_must_fail git check-ref-format --branch @{-1} >actual &&

171 + test_must_be_empty actual

172 +'

173 +

174 +test_expect_success 'check-ref-format --branch master from non-repo' '

175 + echo master >expect &&

176 + nongit git check-ref-format --branch master >actual &&

177 + test_cmp expect actual

178 +'

179 +

180 valid_ref_normalized() {

181 prereq=

182 case $1 in