Merge branch 'nd/diff-parseopt'

The diff machinery, one of the oldest parts of the system, which
long predates the parse-options API, uses fairly long and complex
handcrafted option parser.  This is being rewritten to use the
parse-options API.

* nd/diff-parseopt:
  diff.c: convert --raw
  diff.c: convert -W|--[no-]function-context
  diff.c: convert -U|--unified
  diff.c: convert -u|-p|--patch
  diff.c: prepare to use parse_options() for parsing
  diff.h: avoid bit fields in struct diff_flags
  diff.h: keep forward struct declarations sorted
  parse-options: allow ll_callback with OPTION_CALLBACK
  parse-options: avoid magic return codes
  parse-options: stop abusing 'callback' for lowlevel callbacks
  parse-options: add OPT_BITOP()
  parse-options: disable option abbreviation with PARSE_OPT_KEEP_UNKNOWN
  parse-options: add one-shot mode
  parse-options.h: remove extern on function prototypes

1 files changed, 59 insertions, 12 deletions

diff --git a/diff.c b/diff.c
index 5306c48652..1a1f215787 100644
--- a/diff.c
+++ b/diff.c
@@ -23,6 +23,7 @@
 #include "argv-array.h"
 #include "graph.h"
 #include "packfile.h"
+#include "parse-options.h"
 #include "help.h"
 
 #ifdef NO_FAST_WORKING_DIRECTORY
@@ -4491,6 +4492,8 @@ static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
 	builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
 }
 
+static void prep_parse_options(struct diff_options *options);
+
 void repo_diff_setup(struct repository *r, struct diff_options *options)
 {
 	memcpy(options, &default_diff_options, sizeof(*options));
@@ -4532,6 +4535,8 @@ void repo_diff_setup(struct repository *r, struct diff_options *options)
 
 	options->color_moved = diff_color_moved_default;
 	options->color_moved_ws_handling = diff_color_moved_ws_default;
+
+	prep_parse_options(options);
 }
 
 void diff_setup_done(struct diff_options *options)
@@ -4635,6 +4640,8 @@ void diff_setup_done(struct diff_options *options)
 
 	if (!options->use_color || external_diff())
 		options->color_moved = 0;
+
+	FREE_AND_NULL(options->parseopts);
 }
 
 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
@@ -4926,6 +4933,47 @@ static int parse_objfind_opt(struct diff_options *opt, const char *arg)
 	return 1;
 }
 
+static int diff_opt_unified(const struct option *opt,
+			    const char *arg, int unset)
+{
+	struct diff_options *options = opt->value;
+	char *s;
+
+	BUG_ON_OPT_NEG(unset);
+
+	options->context = strtol(arg, &s, 10);
+	if (*s)
+		return error(_("%s expects a numerical value"), "--unified");
+	enable_patch_output(&options->output_format);
+
+	return 0;
+}
+
+static void prep_parse_options(struct diff_options *options)
+{
+	struct option parseopts[] = {
+		OPT_GROUP(N_("Diff output format options")),
+		OPT_BITOP('p', "patch", &options->output_format,
+			  N_("generate patch"),
+			  DIFF_FORMAT_PATCH, DIFF_FORMAT_NO_OUTPUT),
+		OPT_BITOP('u', NULL, &options->output_format,
+			  N_("generate patch"),
+			  DIFF_FORMAT_PATCH, DIFF_FORMAT_NO_OUTPUT),
+		OPT_CALLBACK_F('U', "unified", options, N_("<n>"),
+			       N_("generate diffs with <n> lines context"),
+			       PARSE_OPT_NONEG, diff_opt_unified),
+		OPT_BOOL('W', "function-context", &options->flags.funccontext,
+			 N_("generate diffs with <n> lines context")),
+		OPT_BIT_F(0, "raw", &options->output_format,
+			  N_("generate the diff in raw format"),
+			  DIFF_FORMAT_RAW, PARSE_OPT_NONEG),
+		OPT_END()
+	};
+
+	ALLOC_ARRAY(options->parseopts, ARRAY_SIZE(parseopts));
+	memcpy(options->parseopts, parseopts, sizeof(parseopts));
+}
+
 int diff_opt_parse(struct diff_options *options,
 		   const char **av, int ac, const char *prefix)
 {
@@ -4936,13 +4984,18 @@ int diff_opt_parse(struct diff_options *options,
 	if (!prefix)
 		prefix = "";
 
+	ac = parse_options(ac, av, prefix, options->parseopts, NULL,
+			   PARSE_OPT_KEEP_DASHDASH |
+			   PARSE_OPT_KEEP_UNKNOWN |
+			   PARSE_OPT_NO_INTERNAL_HELP |
+			   PARSE_OPT_ONE_SHOT |
+			   PARSE_OPT_STOP_AT_NON_OPTION);
+
+	if (ac)
+		return ac;
+
 	/* Output format options */
-	if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch")
-	    || opt_arg(arg, 'U', "unified", &options->context))
-		enable_patch_output(&options->output_format);
-	else if (!strcmp(arg, "--raw"))
-		options->output_format |= DIFF_FORMAT_RAW;
-	else if (!strcmp(arg, "--patch-with-raw")) {
+	if (!strcmp(arg, "--patch-with-raw")) {
 		enable_patch_output(&options->output_format);
 		options->output_format |= DIFF_FORMAT_RAW;
 	} else if (!strcmp(arg, "--numstat"))
@@ -5230,12 +5283,6 @@ int diff_opt_parse(struct diff_options *options,
 	else if (opt_arg(arg, '\0', "inter-hunk-context",
 			 &options->interhunkcontext))
 		;
-	else if (!strcmp(arg, "-W"))
-		options->flags.funccontext = 1;
-	else if (!strcmp(arg, "--function-context"))
-		options->flags.funccontext = 1;
-	else if (!strcmp(arg, "--no-function-context"))
-		options->flags.funccontext = 0;
 	else if ((argcount = parse_long_opt("output", av, &optarg))) {
 		char *path = prefix_filename(prefix, optarg);
 		options->file = xfopen(path, "w");