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| author | Junio C Hamano <gitster@pobox.com> | 2012-09-13 14:21:44 -0700 |
|---|---|---|
| committer | Junio C Hamano <gitster@pobox.com> | 2012-09-14 10:10:35 -0700 |
| commit | 17bf35a3c7b46df7131681bcc5bee5f12e1caec4 (patch) | |
| tree | 26c22e3e4dce563d22a840d6a9b2f144a2335b57 /grep.c | |
| parent | 785ee4960c3d334cbc2b17ab74d2cebdf1b4db64 (diff) | |
| download | git-17bf35a3c7b46df7131681bcc5bee5f12e1caec4.tar.gz | |
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>
Diffstat (limited to 'grep.c')
| -rw-r--r-- | grep.c | 92 |
1 files changed, 90 insertions, 2 deletions
@@ -332,6 +332,87 @@ static struct grep_expr *compile_pattern_expr(struct grep_pat **list) return compile_pattern_or(list); } +static void indent(int in) +{ + while (in-- > 0) + fputc(' ', stderr); +} + +static void dump_grep_pat(struct grep_pat *p) +{ + switch (p->token) { + case GREP_AND: fprintf(stderr, "*and*"); break; + case GREP_OPEN_PAREN: fprintf(stderr, "*(*"); break; + case GREP_CLOSE_PAREN: fprintf(stderr, "*)*"); break; + case GREP_NOT: fprintf(stderr, "*not*"); break; + case GREP_OR: fprintf(stderr, "*or*"); break; + + case GREP_PATTERN: fprintf(stderr, "pattern"); break; + case GREP_PATTERN_HEAD: fprintf(stderr, "pattern_head"); break; + case GREP_PATTERN_BODY: fprintf(stderr, "pattern_body"); break; + } + + switch (p->token) { + default: break; + case GREP_PATTERN_HEAD: + fprintf(stderr, "<head %d>", p->field); break; + case GREP_PATTERN_BODY: + fprintf(stderr, "<body>"); break; + } + switch (p->token) { + default: break; + case GREP_PATTERN_HEAD: + case GREP_PATTERN_BODY: + case GREP_PATTERN: + fprintf(stderr, "%.*s", (int)p->patternlen, p->pattern); + break; + } + fputc('\n', stderr); +} + +static void dump_grep_expression_1(struct grep_expr *x, int in) +{ + indent(in); + switch (x->node) { + case GREP_NODE_TRUE: + fprintf(stderr, "true\n"); + break; + case GREP_NODE_ATOM: + dump_grep_pat(x->u.atom); + break; + case GREP_NODE_NOT: + fprintf(stderr, "(not\n"); + dump_grep_expression_1(x->u.unary, in+1); + indent(in); + fprintf(stderr, ")\n"); + break; + case GREP_NODE_AND: + fprintf(stderr, "(and\n"); + dump_grep_expression_1(x->u.binary.left, in+1); + dump_grep_expression_1(x->u.binary.right, in+1); + indent(in); + fprintf(stderr, ")\n"); + break; + case GREP_NODE_OR: + fprintf(stderr, "(or\n"); + dump_grep_expression_1(x->u.binary.left, in+1); + dump_grep_expression_1(x->u.binary.right, in+1); + indent(in); + fprintf(stderr, ")\n"); + break; + } +} + +void dump_grep_expression(struct grep_opt *opt) +{ + struct grep_expr *x = opt->pattern_expression; + + if (opt->all_match) + fprintf(stderr, "[all-match]\n"); + dump_grep_expression_1(x, 0); + fflush(NULL); +} + static struct grep_expr *grep_true_expr(void) { struct grep_expr *z = xcalloc(1, sizeof(*z)); @@ -395,7 +476,7 @@ static struct grep_expr *prep_header_patterns(struct grep_opt *opt) return header_expr; } -void compile_grep_patterns(struct grep_opt *opt) +static void compile_grep_patterns_real(struct grep_opt *opt) { struct grep_pat *p; struct grep_expr *header_expr = prep_header_patterns(opt); @@ -415,7 +496,7 @@ void compile_grep_patterns(struct grep_opt *opt) if (opt->all_match || header_expr) opt->extended = 1; - else if (!opt->extended) + else if (!opt->extended && !opt->debug) return; p = opt->pattern_list; @@ -435,6 +516,13 @@ void compile_grep_patterns(struct grep_opt *opt) opt->all_match = 1; } +void compile_grep_patterns(struct grep_opt *opt) +{ + compile_grep_patterns_real(opt); + if (opt->debug) + dump_grep_expression(opt); +} + static void free_pattern_expr(struct grep_expr *x) { switch (x->node) { |