[PATCH] diff: allow unstuck arguments with --diff-algorithm

[John Keeping <john@keeping.me.uk>]

The argument to --diff-algorithm is mandatory, so there is no reason to
require the argument to be stuck to the option with '='.  Change this
for consistency with other Git commands.

Note that this doesi not change the handling of diff-algorithm in
merge-recursive.c since the primary interface to that is via the -X
option to 'git merge' where the unstuck form does not make sense.

Signed-off-by: John Keeping <john@keeping.me.uk>
---
 diff.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/diff.c b/diff.c
index db952a5..e0152f8 100644
--- a/diff.c
+++ b/diff.c
@@ -3596,8 +3596,8 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		options->xdl_opts = DIFF_WITH_ALG(options, PATIENCE_DIFF);
 	else if (!strcmp(arg, "--histogram"))
 		options->xdl_opts = DIFF_WITH_ALG(options, HISTOGRAM_DIFF);
-	else if (!prefixcmp(arg, "--diff-algorithm=")) {
-		long value = parse_algorithm_value(arg+17);
+	else if ((argcount = parse_long_opt("diff-algorithm", av, &optarg))) {
+		long value = parse_algorithm_value(optarg);
 		if (value < 0)
 			return error("option diff-algorithm accepts \"myers\", "
 				     "\"minimal\", \"patience\" and \"histogram\"");
@@ -3605,6 +3605,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		DIFF_XDL_CLR(options, NEED_MINIMAL);
 		options->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK;
 		options->xdl_opts |= value;
+		return argcount;
 	}
 
 	/* flags options */
-- 
1.8.2.540.gf023cfe