Merge branch 'mh/diff-indent-heuristic'

Output from "git diff" can be made easier to read by selecting
which lines are common and which lines are added/deleted
intelligently when the lines before and after the changed section
are the same.  A command line option is added to help with the
experiment to find a good heuristics.

* mh/diff-indent-heuristic:
  blame: honor the diff heuristic options and config
  parse-options: add parse_opt_unknown_cb()
  diff: improve positioning of add/delete blocks in diffs
  xdl_change_compact(): introduce the concept of a change group
  recs_match(): take two xrecord_t pointers as arguments
  is_blank_line(): take a single xrecord_t as argument
  xdl_change_compact(): only use heuristic if group can't be matched
  xdl_change_compact(): fix compaction heuristic to adjust ixo

1 files changed, 12 insertions, 0 deletions

diff --git a/parse-options-cb.c b/parse-options-cb.c
index 9667bc75a0..b5d920914e 100644
--- a/parse-options-cb.c
+++ b/parse-options-cb.c
@@ -159,6 +159,18 @@ int parse_opt_noop_cb(const struct option *opt, const char *arg, int unset)
 }
 
 /**
+ * Report that the option is unknown, so that other code can handle
+ * it. This can be used as a callback together with
+ * OPTION_LOWLEVEL_CALLBACK to allow an option to be documented in the
+ * "-h" output even if it's not being handled directly by
+ * parse_options().
+ */
+int parse_opt_unknown_cb(const struct option *opt, const char *arg, int unset)
+{
+	return -2;
+}
+
+/**
  * Recreates the command-line option in the strbuf.
  */
 static int recreate_opt(struct strbuf *sb, const struct option *opt,