rev-parse --parseopt: allow [*=?!] in argument hints

A line in the input to "rev-parse --parseopt" describes an option by
listing a short and/or long name, optional flags [*=?!], argument hint,
and then whitespace and help string.

We did not allow any of the [*=?!] characters in the argument hints.
The following input

    pair=key=value  equals sign in the hint

used to generate a help line like this:

    --pair=key <value>   equals sign in the hint

and used to expect "pair=key" as the argument name.

That is not very helpful as we generally do not want any of the [*=?!]
characters in the argument names.  But we do want to use at least the
equals sign in the argument hints.

Update the parser to make long argument names stop at the first [*=?!]
character.

Add test case with equals sign in the argument hint and update the test
to perform all the operations in test_expect_success matching the
t/README requirements and allowing commands like

    ./t1502-rev-parse-parseopt.sh --run=1-2

to stop at the test case 2 without any further modification of the test
state area.

Signed-off-by: Ilya Bobyr <ilya.bobyr@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-rev-parse.txt

@@ -311,8 +311,8 @@ Each line of options has this format:
 `<opt-spec>`::
 	its format is the short option character, then the long option name
 	separated by a comma. Both parts are not required, though at least one
-	is necessary. `h,help`, `dry-run` and `f` are all three correct
+	is necessary. May not contain any of the `<flags>` characters.
-	`<opt-spec>`.
+	`h,help`, `dry-run` and `f` are examples of correct `<opt-spec>`.
 
 `<flags>`::
 	`<flags>` are of `*`, `=`, `?` or `!`.

builtin/rev-parse.c

@@ -371,6 +371,7 @@ static int cmd_parseopt(int argc, const char **argv, const char *prefix)
 					N_("output in stuck long form")),
 		OPT_END(),
 	};
+	static const char * const flag_chars = "*=?!";
 
 	struct strbuf sb = STRBUF_INIT, parsed = STRBUF_INIT;
 	const char **usage = NULL;
@@ -400,7 +401,7 @@ static int cmd_parseopt(int argc, const char **argv, const char *prefix)
 	/* parse: (<short>|<short>,<long>|<long>)[*=?!]*<arghint>? SP+ <help> */
 	while (strbuf_getline(&sb, stdin, '\n') != EOF) {
 		const char *s;
-		const char *end;
+		const char *help;
 		struct option *o;
 
 		if (!sb.len)
@@ -410,45 +411,23 @@ static int cmd_parseopt(int argc, const char **argv, const char *prefix)
 		memset(opts + onb, 0, sizeof(opts[onb]));
 
 		o = &opts[onb++];
-		s = strchr(sb.buf, ' ');
+		help = strchr(sb.buf, ' ');
-		if (!s || *sb.buf == ' ') {
+		if (!help || *sb.buf == ' ') {
 			o->type = OPTION_GROUP;
 			o->help = xstrdup(skipspaces(sb.buf));
 			continue;
 		}
 
 		o->type = OPTION_CALLBACK;
-		o->help = xstrdup(skipspaces(s));
+		o->help = xstrdup(skipspaces(help));
 		o->value = &parsed;
 		o->flags = PARSE_OPT_NOARG;
 		o->callback = &parseopt_dump;
 
-		/* Possible argument name hint */
+		/* name(s) */
-		end = s;
+		s = strpbrk(sb.buf, flag_chars);
-		while (s > sb.buf && strchr("*=?!", s[-1]) == NULL)
+		if (s == NULL)
-			--s;
+			s = help;
-		if (s != sb.buf && s != end)
-			o->argh = xmemdupz(s, end - s);
-		if (s == sb.buf)
-			s = end;
-
-		while (s > sb.buf && strchr("*=?!", s[-1])) {
-			switch (*--s) {
-			case '=':
-				o->flags &= ~PARSE_OPT_NOARG;
-				break;
-			case '?':
-				o->flags &= ~PARSE_OPT_NOARG;
-				o->flags |= PARSE_OPT_OPTARG;
-				break;
-			case '!':
-				o->flags |= PARSE_OPT_NONEG;
-				break;
-			case '*':
-				o->flags |= PARSE_OPT_HIDDEN;
-				break;
-			}
-		}
 
 		if (s - sb.buf == 1) /* short option only */
 			o->short_name = *sb.buf;
@@ -458,6 +437,30 @@ static int cmd_parseopt(int argc, const char **argv, const char *prefix)
 			o->short_name = *sb.buf;
 			o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
 		}
+
+		/* flags */
+		while (s < help) {
+			switch (*s++) {
+			case '=':
+				o->flags &= ~PARSE_OPT_NOARG;
+				continue;
+			case '?':
+				o->flags &= ~PARSE_OPT_NOARG;
+				o->flags |= PARSE_OPT_OPTARG;
+				continue;
+			case '!':
+				o->flags |= PARSE_OPT_NONEG;
+				continue;
+			case '*':
+				o->flags |= PARSE_OPT_HIDDEN;
+				continue;
+			}
+			s--;
+			break;
+		}
+
+		if (s < help)
+			o->argh = xmemdupz(s, help - s);
 	}
 	strbuf_release(&sb);
 

t/t1502-rev-parse-parseopt.sh

@@ -3,7 +3,40 @@
 test_description='test git rev-parse --parseopt'
 . ./test-lib.sh
 
-sed -e 's/^|//' >expect <<\END_EXPECT
+test_expect_success 'setup optionspec' '
+	sed -e "s/^|//" >optionspec <<\EOF
+|some-command [options] <args>...
+|
+|some-command does foo and bar!
+|--
+|h,help    show the help
+|
+|foo       some nifty option --foo
+|bar=      some cool option --bar with an argument
+|b,baz     a short and long option
+|
+| An option group Header
+|C?        option C with an optional argument
+|d,data?   short and long option with an optional argument
+|
+| Argument hints
+|B=arg     short option required argument
+|bar2=arg  long option required argument
+|e,fuz=with-space  short and long option required argument
+|s?some    short option optional argument
+|long?data long option optional argument
+|g,fluf?path     short and long option optional argument
+|longest=very-long-argument-hint  a very long argument hint
+|pair=key=value  with an equals sign in the hint
+|short-hint=a    with a one symbol hint
+|
+|Extras
+|extra1    line above used to cause a segfault but no longer does
+EOF
+'
+
+test_expect_success 'test --parseopt help output' '
+	sed -e "s/^|//" >expect <<\END_EXPECT &&
 |cat <<\EOF
 |usage: some-command [options] <args>...
 |
@@ -28,49 +61,23 @@ sed -e 's/^|//' >expect <<\END_EXPECT
 |    -g, --fluf[=<path>]   short and long option optional argument
 |    --longest <very-long-argument-hint>
 |                          a very long argument hint
+|    --pair <key=value>    with an equals sign in the hint
+|    --short-hint <a>      with a one symbol hint
 |
 |Extras
 |    --extra1              line above used to cause a segfault but no longer does
 |
 |EOF
 END_EXPECT
-
-sed -e 's/^|//' >optionspec <<\EOF
-|some-command [options] <args>...
-|
-|some-command does foo and bar!
-|--
-|h,help    show the help
-|
-|foo       some nifty option --foo
-|bar=      some cool option --bar with an argument
-|b,baz     a short and long option
-|
-| An option group Header
-|C?        option C with an optional argument
-|d,data?   short and long option with an optional argument
-|
-| Argument hints
-|B=arg     short option required argument
-|bar2=arg  long option required argument
-|e,fuz=with-space  short and long option required argument
-|s?some    short option optional argument
-|long?data long option optional argument
-|g,fluf?path     short and long option optional argument
-|longest=very-long-argument-hint  a very long argument hint
-|
-|Extras
-|extra1    line above used to cause a segfault but no longer does
-EOF
-
-test_expect_success 'test --parseopt help output' '
 	test_expect_code 129 git rev-parse --parseopt -- -h > output < optionspec &&
 	test_i18ncmp expect output
 '
 
-cat > expect <<EOF
+test_expect_success 'setup expect.1' "
+	cat > expect <<EOF
 set -- --foo --bar 'ham' -b -- 'arg'
 EOF
+"
 
 test_expect_success 'test --parseopt' '
 	git rev-parse --parseopt -- --foo --bar=ham --baz arg < optionspec > output &&
@@ -82,9 +89,11 @@ test_expect_success 'test --parseopt with mixed options and arguments' '
 	test_cmp expect output
 '
 
-cat > expect <<EOF
+test_expect_success 'setup expect.2' "
+	cat > expect <<EOF
 set -- --foo -- 'arg' '--bar=ham'
 EOF
+"
 
 test_expect_success 'test --parseopt with --' '
 	git rev-parse --parseopt -- --foo -- arg --bar=ham < optionspec > output &&
@@ -96,54 +105,66 @@ test_expect_success 'test --parseopt --stop-at-non-option' '
 	test_cmp expect output
 '
 
-cat > expect <<EOF
+test_expect_success 'setup expect.3' "
+	cat > expect <<EOF
 set -- --foo -- '--' 'arg' '--bar=ham'
 EOF
+"
 
 test_expect_success 'test --parseopt --keep-dashdash' '
 	git rev-parse --parseopt --keep-dashdash -- --foo -- arg --bar=ham < optionspec > output &&
 	test_cmp expect output
 '
 
-cat >expect <<EOF
+test_expect_success 'setup expect.4' "
+	cat >expect <<EOF
 set -- --foo -- '--' 'arg' '--spam=ham'
 EOF
+"
 
 test_expect_success 'test --parseopt --keep-dashdash --stop-at-non-option with --' '
 	git rev-parse --parseopt --keep-dashdash --stop-at-non-option -- --foo -- arg --spam=ham <optionspec >output &&
 	test_cmp expect output
 '
 
-cat > expect <<EOF
+test_expect_success 'setup expect.5' "
+	cat > expect <<EOF
 set -- --foo -- 'arg' '--spam=ham'
 EOF
+"
 
 test_expect_success 'test --parseopt --keep-dashdash --stop-at-non-option without --' '
 	git rev-parse --parseopt --keep-dashdash --stop-at-non-option -- --foo arg --spam=ham <optionspec >output &&
 	test_cmp expect output
 '
 
-cat > expect <<EOF
+test_expect_success 'setup expect.6' "
+	cat > expect <<EOF
 set -- --foo --bar='z' --baz -C'Z' --data='A' -- 'arg'
 EOF
+"
 
 test_expect_success 'test --parseopt --stuck-long' '
 	git rev-parse --parseopt --stuck-long -- --foo --bar=z -b arg -CZ -dA <optionspec >output &&
 	test_cmp expect output
 '
 
-cat > expect <<EOF
+test_expect_success 'setup expect.7' "
+	cat > expect <<EOF
 set -- --data='' -C --baz -- 'arg'
 EOF
+"
 
 test_expect_success 'test --parseopt --stuck-long and empty optional argument' '
 	git rev-parse --parseopt --stuck-long -- --data= arg -C -b <optionspec >output &&
 	test_cmp expect output
 '
 
-cat > expect <<EOF
+test_expect_success 'setup expect.8' "
+	cat > expect <<EOF
 set -- --data --baz -- 'arg'
 EOF
+"
 
 test_expect_success 'test --parseopt --stuck-long and long option with unset optional argument' '
 	git rev-parse --parseopt --stuck-long -- --data arg -b <optionspec >output &&