rebase -x: sanity check command

If the user gives an empty argument to --exec then git creates a todo
list that it cannot parse. 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'.

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.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/rebase.c b/builtin/rebase.c
index b5c99ec10c200a5fccb293c0acadae80642f2808..f9f231a5f09a15ee5b62fd81aebc898c4c1804bf 100644 (file)
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -793,6 +793,19 @@ static void set_reflog_action(struct rebase_options *options)
        strbuf_release(&buf);
 }
 
+static int check_exec_cmd(const char *cmd)
+{
+       if (strchr(cmd, '\n'))
+               return error(_("exec commands cannot contain newlines"));
+
+       /* Does the command consist purely of whitespace? */
+       if (!cmd[strspn(cmd, " \t\r\f\v")])
+               return error(_("empty exec command"));
+
+       return 0;
+}
+
+
 int cmd_rebase(int argc, const char **argv, const char *prefix)
 {
        struct rebase_options options = {
@@ -1130,6 +1143,10 @@ 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 7a440e08d8257487ae2f47b159d11e37a5166df8..c98f64eb2d288843bfe8123bdac3176bda4b976c 100755 (executable)
--- 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" &&