grep: teach --debug option to dump the parse tree
Our "grep" allows complex boolean expressions to be formed to match
each individual line with operators like --and, '(', ')' and --not.
Introduce the "--debug" option to show the parse tree to help people
who want to debug and enhance it.
Also "log" learns "--grep-debug" option to do the same. The command
line parser to the log family is a lot more limited than the general
"git grep" parser, but it has special handling for header matching
(e.g. "--author"), and a parse tree is valuable when working on it.
Note that "--all-match" is *not* any individual node in the parse
tree. It is an instruction to the evaluator to check all the nodes
in the top-level backbone have matched and reject a document as
non-matching otherwise.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/grep.h b/grep.h
index ed7de6b..bf5be5a 100644
--- a/grep.h
+++ b/grep.h
@@ -90,6 +90,7 @@
int word_regexp;
int fixed;
int all_match;
+ int debug;
#define GREP_BINARY_DEFAULT 0
#define GREP_BINARY_NOMATCH 1
#define GREP_BINARY_TEXT 2
