Re: [PATCH] rebase -x: sanity check command
- Date: Mon, 28 Jan 2019 23:03:30 +0100 (STD)
- From: Johannes Schindelin <Johannes.Schindelin@xxxxxx>
- Subject: Re: [PATCH] rebase -x: sanity check command
Hi Phillip,
On Mon, 28 Jan 2019, Phillip Wood wrote:
> From: Phillip Wood <phillip.wood@xxxxxxxxxxxxx>
>
> If the user gives an empty argument to --exec then the rebase starts to
> run before erroring out with
>
> error: missing arguments for exec
> error: invalid line 2: exec
> You can fix this with 'git rebase --edit-todo' and then run 'git rebase --continue'.
> Or you can abort the rebase with 'git rebase --abort'.
And that's the same if you specify an incorrect command.
In both cases, I would probably heed the second line of the advice: git
rebase --abort.
> Instead check for empty commands before starting the rebase.
>
> Also check that the command does not contain any newlines as the
> todo-list format is unable to cope with multiline commands. Note that
> this changes the behavior, before this change one could do
>
> git rebase --exec='echo one
> exec echo two'
>
> and it would insert two exec lines in the todo list, now it will error
> out.
This, however, makes a ton of sense to me.
> diff --git a/builtin/rebase.c b/builtin/rebase.c
> index 00de70365e..b6c54b03c1 100644
> --- a/builtin/rebase.c
> +++ b/builtin/rebase.c
> @@ -793,6 +793,24 @@ static void set_reflog_action(struct rebase_options *options)
> strbuf_release(&buf);
> }
>
> +static int check_exec_cmd(const char *cmd)
> +{
> + int non_blank = 0;
> +
> + while (*cmd) {
> + if (*cmd == '\n')
> + return error(_("exec commands cannot contain newlines"));
> + if (!isspace(*cmd))
> + non_blank = 1;
> + cmd++;
> + }
> +
> + if (non_blank)
> + return 0;
We are not in a performance critical path here, so I would prefer the
readability of this code:
if (strchr(cmd, '\n'))
return error(...);
And if you *really* must,
/* Does the command consist purely of whitespace? */
if (!cmd[strspn(cmd, " \t\r\n")])
return error(...);
But as I suggested also in a reply to Junio's answer: where would we stop
to validate the commands?
Ciao,
Dscho
> +
> + return error(_("empty exec command"));
> +}
> +
> int cmd_rebase(int argc, const char **argv, const char *prefix)
> {
> struct rebase_options options = {
> @@ -1130,6 +1148,10 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
> }
> }
>
> + for (i = 0; i < exec.nr; i++)
> + if (check_exec_cmd(exec.items[i].string))
> + exit(1);
> +
> if (!(options.flags & REBASE_NO_QUIET))
> argv_array_push(&options.git_am_opts, "-q");
>
> diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
> index 7a440e08d8..c98f64eb2d 100755
> --- a/t/t3404-rebase-interactive.sh
> +++ b/t/t3404-rebase-interactive.sh
> @@ -147,6 +147,25 @@ test_expect_success 'rebase -i with the exec command checks tree cleanness' '
> git rebase --continue
> '
>
> +test_expect_success 'rebase -x with empty command fails' '
> + test_when_finished "git rebase --abort ||:" &&
> + test_must_fail git rebase -x "" @ 2>actual &&
> + test_write_lines "error: empty exec command" >expected &&
> + test_i18ncmp expected actual &&
> + test_must_fail git rebase -x " " @ 2>actual &&
> + test_i18ncmp expected actual
> +'
> +
> +LF='
> +'
> +test_expect_success 'rebase -x with newline in command fails' '
> + test_when_finished "git rebase --abort ||:" &&
> + test_must_fail git rebase -x "a${LF}b" @ 2>actual &&
> + test_write_lines "error: exec commands cannot contain newlines" \
> + >expected &&
> + test_i18ncmp expected actual
> +'
> +
> test_expect_success 'rebase -i with exec of inexistent command' '
> git checkout master &&
> test_when_finished "git rebase --abort" &&
> --
> 2.20.1
>
>