From 19e8789b236dfe33667747d5523d6689bb59b5ef Mon Sep 17 00:00:00 2001 From: Jeff King Date: Tue, 6 Aug 2019 10:39:58 -0400 Subject: [PATCH 1/3] revision: allow --end-of-options to end option parsing There's currently no robust way to tell Git that a particular option is meant to be a revision, and not an option. So if you have a branch "refs/heads/--foo", you cannot just say: git rev-list --foo You can say: git rev-list refs/heads/--foo But that breaks down if you don't know the refname, and in particular if you're a script passing along a value from elsewhere. In most programs, you can use "--" to end option parsing, like this: some-prog -- "$revision" But that doesn't work for the revision parser, because "--" is already meaningful there: it separates revisions from pathspecs. So we need some other marker to separate options from revisions. This patch introduces "--end-of-options", which serves that purpose: git rev-list --oneline --end-of-options "$revision" will work regardless of what's in "$revision" (well, if you say "--" it may fail, but it won't do something dangerous, like triggering an unexpected option). The name is verbose, but that's probably a good thing; this is meant to be used for scripted invocations where readability is more important than terseness. One alternative would be to introduce an explicit option to mark a revision, like: git rev-list --oneline --revision="$revision" That's slightly _more_ informative than this commit (because it makes even something silly like "--" unambiguous). But the pattern of using a separator like "--" is well established in git and in other commands, and it makes some scripting tasks simpler like: git rev-list --end-of-options "$@" There's no documentation in this patch, because it will make sense to describe the feature once it is available everywhere (and support will be added in further patches). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- revision.c | 8 +++++++- t/t6000-rev-list-misc.sh | 8 ++++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/revision.c b/revision.c index 07412297f0..51690e480d 100644 --- a/revision.c +++ b/revision.c @@ -2523,6 +2523,7 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s int i, flags, left, seen_dashdash, got_rev_arg = 0, revarg_opt; struct argv_array prune_data = ARGV_ARRAY_INIT; const char *submodule = NULL; + int seen_end_of_options = 0; if (opt) submodule = opt->submodule; @@ -2552,7 +2553,7 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s revarg_opt |= REVARG_CANNOT_BE_FILENAME; for (left = i = 1; i < argc; i++) { const char *arg = argv[i]; - if (*arg == '-') { + if (!seen_end_of_options && *arg == '-') { int opts; opts = handle_revision_pseudo_opt(submodule, @@ -2574,6 +2575,11 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s continue; } + if (!strcmp(arg, "--end-of-options")) { + seen_end_of_options = 1; + continue; + } + opts = handle_revision_opt(revs, argc - i, argv + i, &left, argv, opt); if (opts > 0) { diff --git a/t/t6000-rev-list-misc.sh b/t/t6000-rev-list-misc.sh index 52a9e38d66..b8cf82349b 100755 --- a/t/t6000-rev-list-misc.sh +++ b/t/t6000-rev-list-misc.sh @@ -140,4 +140,12 @@ test_expect_success '--header shows a NUL after each commit' ' test_cmp expect actual ' +test_expect_success 'rev-list --end-of-options' ' + git update-ref refs/heads/--output=yikes HEAD && + git rev-list --end-of-options --output=yikes >actual && + test_path_is_missing yikes && + git rev-list HEAD >expect && + test_cmp expect actual +' + test_done From 51b4594b4024d5cb2b4ace36ff932affa31c03f4 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Tue, 6 Aug 2019 10:40:16 -0400 Subject: [PATCH 2/3] parse-options: allow --end-of-options as a synonym for "--" The revision option parser recently learned about --end-of-options, but that's not quite enough for all callers. Some of them, like git-log, pick out some options using parse_options(), and then feed the remainder to setup_revisions(). For those cases we need to stop parse_options() from finding more options when it sees --end-of-options, and to retain that option in argv so that setup_revisions() can see it as well. Let's handle this the same as we do "--". We can even piggy-back on the handling of PARSE_OPT_KEEP_DASHDASH, because any caller that wants to retain one will want to retain the other. I've included two tests here. The "log" test covers "--source", which is one of the options it handles with parse_options(), and would fail before this patch. There's also a test that uses the parse-options helper directly. That confirms that the option is handled correctly even in cases without KEEP_DASHDASH or setup_revisions(). I.e., it is safe to use --end-of-options in place of "--" in other programs. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- parse-options.c | 3 ++- t/t0040-parse-options.sh | 7 +++++++ t/t4202-log.sh | 7 +++++++ 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/parse-options.c b/parse-options.c index 87b26a1d92..b42f54d48b 100644 --- a/parse-options.c +++ b/parse-options.c @@ -780,7 +780,8 @@ int parse_options_step(struct parse_opt_ctx_t *ctx, continue; } - if (!arg[2]) { /* "--" */ + if (!arg[2] /* "--" */ || + !strcmp(arg + 2, "end-of-options")) { if (!(ctx->flags & PARSE_OPT_KEEP_DASHDASH)) { ctx->argc--; ctx->argv++; diff --git a/t/t0040-parse-options.sh b/t/t0040-parse-options.sh index cebc77fab0..705a136ed9 100755 --- a/t/t0040-parse-options.sh +++ b/t/t0040-parse-options.sh @@ -399,4 +399,11 @@ test_expect_success 'GIT_TEST_DISALLOW_ABBREVIATED_OPTIONS works' ' test-tool parse-options --ye ' +test_expect_success '--end-of-options treats remainder as args' ' + test-tool parse-options \ + --expect="verbose: -1" \ + --expect="arg 00: --verbose" \ + --end-of-options --verbose +' + test_done diff --git a/t/t4202-log.sh b/t/t4202-log.sh index c20209324c..e88ccb04a9 100755 --- a/t/t4202-log.sh +++ b/t/t4202-log.sh @@ -1707,4 +1707,11 @@ test_expect_success '--exclude-promisor-objects does not BUG-crash' ' test_must_fail git log --exclude-promisor-objects source-a ' +test_expect_success 'log --end-of-options' ' + git update-ref refs/heads/--source HEAD && + git log --end-of-options --source >actual && + git log >expect && + test_cmp expect actual +' + test_done From 67feca3b1c45a51b204253039139b46cc07e145f Mon Sep 17 00:00:00 2001 From: Jeff King Date: Tue, 6 Aug 2019 10:40:30 -0400 Subject: [PATCH 3/3] gitcli: document --end-of-options Now that --end-of-options is available for any users of setup_revisions() or parse_options(), which should be effectively everywhere, we can guide people to use it for all their disambiguating needs. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- Documentation/gitcli.txt | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/gitcli.txt b/Documentation/gitcli.txt index 1ed3ca33b7..4b32876b6e 100644 --- a/Documentation/gitcli.txt +++ b/Documentation/gitcli.txt @@ -37,6 +37,12 @@ arguments. Here are the rules: file called HEAD in your work tree, `git diff HEAD` is ambiguous, and you have to say either `git diff HEAD --` or `git diff -- HEAD` to disambiguate. + + * Because `--` disambiguates revisions and paths in some commands, it + cannot be used for those commands to separate options and revisions. + You can use `--end-of-options` for this (it also works for commands + that do not distinguish between revisions in paths, in which case it + is simply an alias for `--`). + When writing a script that is expected to handle random user-input, it is a good practice to make it explicit which arguments are which by placing