diff: Introduce --diff-algorithm command line option

diff --git a/diff.c b/diff.c
index d2be7777930eee055ad317cbb24a0d65f4ce441b..0724fa6ff6c4312733e520d59f88ea12740d408d 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -144,7 +144,7 @@ static int git_config_rename(const char *var, const char *value)
        return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
 }
 
-static long parse_algorithm_value(const char *value)
+long parse_algorithm_value(const char *value)
 {
        if (!value)
                return -1;
@@ -3634,6 +3634,16 @@ 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);
+               if (value < 0)
+                       return error("option diff-algorithm accepts \"myers\", "
+                                    "\"minimal\", \"patience\" and \"histogram\"");
+               /* clear out previous settings */
+               DIFF_XDL_CLR(options, NEED_MINIMAL);
+               options->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK;
+               options->xdl_opts |= value;
+       }
 
        /* flags options */
        else if (!strcmp(arg, "--binary")) {