{"thread":{"id":"56581","subject":"[PATCH v8 1/2] grep: refactor next_match() and match_one_pattern() for external use","startedAt":"2021-09-24T15:50:22Z","lastAt":"2021-09-28T00:03:37Z","messageCount":4,"participants":["Hamza Mahfooz","Junio C Hamano"],"isPatch":true,"patchVersion":8,"patchTotal":2},"messages":[{"id":"436967","messageId":"20210924155000.1259649-1-someguy@effective-light.com","threadId":"56581","inReplyTo":null,"subject":"[PATCH v8 1/2] grep: refactor next_match() and match_one_pattern() for external use","fromName":"Hamza Mahfooz","fromEmail":"someguy@effective-light.com","sentAt":"2021-09-24T15:49:59Z","receivedAt":"2021-09-24T15:50:22Z","isPatch":true,"sender":{"key":"someguy@effective-light.com","avatar":"https://avatars.githubusercontent.com/u/3885502?v=4"},"body":"These changes are made in preparation of, the colorization support for the\n\"git log\" subcommands that, rely on regex functionality (i.e. \"--author\",\n\"--committer\" and \"--grep\"). These changes are necessary primarily because\nmatch_one_pattern() expects header lines to be prefixed, however, in\npretty, the prefixes are stripped from the lines because the name-email\npairs need to go through additional parsing, before they can be printed and\nbecause next_match() doesn't handle the case of\n\"ctx == GREP_CONTEXT_HEAD\" at all. So, teach next_match() how to handle the\nnew case and move match_one_pattern()'s core logic to\nheadless_match_one_pattern() while preserving match_one_pattern()'s uses\nthat depend on the additional processing.\n\nSigned-off-by: Hamza Mahfooz <someguy@effective-light.com>\n---\nv5: separate grep changes from pretty changes.\n\nv6: rescope some variables.\n\nv7: export header_field[] and allow for subsequent matches on header lines\n    in match_one_pattern().\n\nv8: add headless_match_one_pattern() and move header_field[] back.\n---\n grep.c | 83 ++++++++++++++++++++++++++++++++++++----------------------\n grep.h |  4 +++\n 2 files changed, 55 insertions(+), 32 deletions(-)\n\ndiff --git a/grep.c b/grep.c\nindex 14fe8a0fd2..e46b046638 100644\n--- a/grep.c\n+++ b/grep.c\n@@ -944,37 +944,19 @@ static struct {\n \t{ \"reflog \", 7 },\n };\n \n-static int match_one_pattern(struct grep_pat *p,\n-\t\t\t     const char *bol, const char *eol,\n-\t\t\t     enum grep_context ctx,\n-\t\t\t     regmatch_t *pmatch, int eflags)\n+static int headerless_match_one_pattern(struct grep_pat *p,\n+\t\t\t\t\tconst char *bol, const char *eol,\n+\t\t\t\t\tenum grep_context ctx,\n+\t\t\t\t\tregmatch_t *pmatch, int eflags)\n {\n \tint hit = 0;\n \tconst char *start = bol;\n \n \tif ((p->token != GREP_PATTERN) &&\n-\t    ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))\n+\t    ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)) &&\n+\t    ((p->token == GREP_PATTERN_BODY) != (ctx == GREP_CONTEXT_BODY)))\n \t\treturn 0;\n \n-\tif (p->token == GREP_PATTERN_HEAD) {\n-\t\tconst char *field;\n-\t\tsize_t len;\n-\t\tassert(p->field < ARRAY_SIZE(header_field));\n-\t\tfield = header_field[p->field].field;\n-\t\tlen = header_field[p->field].len;\n-\t\tif (strncmp(bol, field, len))\n-\t\t\treturn 0;\n-\t\tbol += len;\n-\t\tswitch (p->field) {\n-\t\tcase GREP_HEADER_AUTHOR:\n-\t\tcase GREP_HEADER_COMMITTER:\n-\t\t\tstrip_timestamp(bol, &eol);\n-\t\t\tbreak;\n-\t\tdefault:\n-\t\t\tbreak;\n-\t\t}\n-\t}\n-\n  again:\n \thit = patmatch(p, bol, eol, pmatch, eflags);\n \n@@ -1025,6 +1007,36 @@ static int match_one_pattern(struct grep_pat *p,\n \treturn hit;\n }\n \n+static int match_one_pattern(struct grep_pat *p,\n+\t\t\t     const char *bol, const char *eol,\n+\t\t\t     enum grep_context ctx, regmatch_t *pmatch,\n+\t\t\t     int eflags)\n+{\n+\tconst char *field;\n+\tsize_t len;\n+\n+\tif (p->token == GREP_PATTERN_HEAD) {\n+\t\tassert(p->field < ARRAY_SIZE(header_field));\n+\t\tfield = header_field[p->field].field;\n+\t\tlen = header_field[p->field].len;\n+\t\tif (strncmp(bol, field, len))\n+\t\t\treturn 0;\n+\t\tbol += len;\n+\n+\t\tswitch (p->field) {\n+\t\tcase GREP_HEADER_AUTHOR:\n+\t\tcase GREP_HEADER_COMMITTER:\n+\t\t\tstrip_timestamp(bol, &eol);\n+\t\t\tbreak;\n+\t\tdefault:\n+\t\t\tbreak;\n+\t\t}\n+\t}\n+\n+\treturn headerless_match_one_pattern(p, bol, eol, ctx, pmatch, eflags);\n+}\n+\n+\n static int match_expr_eval(struct grep_opt *opt, struct grep_expr *x,\n \t\t\t   const char *bol, const char *eol,\n \t\t\t   enum grep_context ctx, ssize_t *col,\n@@ -1143,7 +1155,7 @@ static int match_next_pattern(struct grep_pat *p,\n {\n \tregmatch_t match;\n \n-\tif (!match_one_pattern(p, bol, eol, ctx, &match, eflags))\n+\tif (!headerless_match_one_pattern(p, bol, eol, ctx, &match, eflags))\n \t\treturn 0;\n \tif (match.rm_so < 0 || match.rm_eo < 0)\n \t\treturn 0;\n@@ -1158,22 +1170,28 @@ static int match_next_pattern(struct grep_pat *p,\n \treturn 1;\n }\n \n-static int next_match(struct grep_opt *opt,\n-\t\t      const char *bol, const char *eol,\n-\t\t      enum grep_context ctx, regmatch_t *pmatch, int eflags)\n+int grep_next_match(struct grep_opt *opt,\n+\t\t    const char *bol, const char *eol,\n+\t\t    enum grep_context ctx, regmatch_t *pmatch,\n+\t\t    enum grep_header_field field, int eflags)\n {\n \tstruct grep_pat *p;\n \tint hit = 0;\n \n \tpmatch->rm_so = pmatch->rm_eo = -1;\n \tif (bol < eol) {\n-\t\tfor (p = opt->pattern_list; p; p = p->next) {\n+\t\tfor (p = ((ctx == GREP_CONTEXT_HEAD)\n+\t\t\t   ? opt->header_list : opt->pattern_list);\n+\t\t\t  p; p = p->next) {\n \t\t\tswitch (p->token) {\n \t\t\tcase GREP_PATTERN: /* atom */\n \t\t\tcase GREP_PATTERN_HEAD:\n \t\t\tcase GREP_PATTERN_BODY:\n-\t\t\t\thit |= match_next_pattern(p, bol, eol, ctx,\n-\t\t\t\t\t\t\t  pmatch, eflags);\n+\t\t\t\tif ((field == GREP_HEADER_FIELD_MAX) ||\n+\t\t\t\t    (p->field == field))\n+\t\t\t\t\thit |= match_next_pattern(p, bol, eol,\n+\t\t\t\t\t\t\t\t  ctx, pmatch,\n+\t\t\t\t\t\t\t\t  eflags);\n \t\t\t\tbreak;\n \t\t\tdefault:\n \t\t\t\tbreak;\n@@ -1261,7 +1279,8 @@ static void show_line(struct grep_opt *opt,\n \t\t\telse if (sign == '=')\n \t\t\t\tline_color = opt->colors[GREP_COLOR_FUNCTION];\n \t\t}\n-\t\twhile (next_match(opt, bol, eol, ctx, &match, eflags)) {\n+\t\twhile (grep_next_match(opt, bol, eol, ctx, &match,\n+\t\t\t\t       GREP_HEADER_FIELD_MAX, eflags)) {\n \t\t\tif (match.rm_so == match.rm_eo)\n \t\t\t\tbreak;\n \ndiff --git a/grep.h b/grep.h\nindex 3cb8a83ae8..521068308e 100644\n--- a/grep.h\n+++ b/grep.h\n@@ -190,6 +190,10 @@ void append_header_grep_pattern(struct grep_opt *, enum grep_header_field, const\n void compile_grep_patterns(struct grep_opt *opt);\n void free_grep_patterns(struct grep_opt *opt);\n int grep_buffer(struct grep_opt *opt, const char *buf, unsigned long size);\n+int grep_next_match(struct grep_opt *opt,\n+\t\t    const char *bol, const char *eol,\n+\t\t    enum grep_context ctx, regmatch_t *pmatch,\n+\t\t    enum grep_header_field field, int eflags);\n \n struct grep_source {\n \tchar *name;\n-- \n2.33.0\n\n"},{"id":"436968","messageId":"20210924155000.1259649-2-someguy@effective-light.com","threadId":"56581","inReplyTo":"20210924155000.1259649-1-someguy@effective-light.com","subject":"[PATCH v8 2/2] pretty: colorize pattern matches in commit messages","fromName":"Hamza Mahfooz","fromEmail":"someguy@effective-light.com","sentAt":"2021-09-24T15:50:00Z","receivedAt":"2021-09-24T15:50:25Z","isPatch":true,"sender":{"key":"someguy@effective-light.com","avatar":"https://avatars.githubusercontent.com/u/3885502?v=4"},"body":"The \"git log\" command limits its output to the commits that contain strings\nmatched by a pattern when the \"--grep=<pattern>\" option is used, but unlike\noutput from \"git grep -e <pattern>\", the matches are not highlighted,\nmaking them harder to spot.\n\nTeach the pretty-printer code to highlight matches from the\n\"--grep=<pattern>\", \"--author=<pattern>\" and \"--committer=<pattern>\"\noptions (to view the last one, you may have to ask for --pretty=fuller).\n\nAlso, it must be noted that we are effectively greping the content twice,\nhowever it only slows down \"git log --author=^H\" on this repository by\naround 1-2% (compared to v2.33.0), so it should be a small enough slow\ndown to justify the addition of the feature.\n\nSigned-off-by: Hamza Mahfooz <someguy@effective-light.com>\n---\nv2: make the commit message whole (add the missing ingredients), rename\n    append_matched_line() to append_line_with_color(), use\n    colors[GREP_COLOR_MATCH_SELECTED] instead of\n    colors[GREP_COLOR_MATCH_CONTEXT], allow the background color to be\n    customized, don't copy strings to a buffer when not coloring in\n    append_line_with_color(), rename next_match() to grep_next_match(),\n    repurpose grep_next_match()/match_one_pattern() for use in\n    append_line_with_color() (allowing us to remove duplicated matching\n    code in append_line_with_color()), document how to customize the\n    feature and modify some of the tests to fit the feature better.\n\nv3: fix a formatting issue with the added documentation.\n\nv4: add strbuf_add_with_color(), use the correct color code scheme in the\n    unit tests and add more unit tests.\n\nv5: separate grep changes from pretty changes and add some performance\n    analysis in the commit message.\n\nv6: put the documentation in the correct place, cleanup pretty.c and\n    format the unit tests according to the current convention.\n\nv7: get rid of all manual strbuf management, constify where now appropriate\n    and fix the header line prefix issue properly.\n\nv8: remove code that relies on grep_header_fields[].\n---\n Documentation/config/color.txt |   7 ++-\n pretty.c                       | 101 +++++++++++++++++++++++++++++----\n t/t4202-log.sh                 |  51 +++++++++++++++++\n 3 files changed, 145 insertions(+), 14 deletions(-)\n\ndiff --git a/Documentation/config/color.txt b/Documentation/config/color.txt\nindex e05d520a86..91d9a9da32 100644\n--- a/Documentation/config/color.txt\n+++ b/Documentation/config/color.txt\n@@ -104,9 +104,12 @@ color.grep.<slot>::\n `matchContext`;;\n \tmatching text in context lines\n `matchSelected`;;\n-\tmatching text in selected lines\n+\tmatching text in selected lines. Also, used to customize the following\n+\tlinkgit:git-log[1] subcommands: `--grep`, `--author` and `--committer`.\n `selected`;;\n-\tnon-matching text in selected lines\n+\tnon-matching text in selected lines. Also, used to customize the\n+\tfollowing linkgit:git-log[1] subcommands: `--grep`, `--author` and\n+\t`--committer`.\n `separator`;;\n \tseparators between fields on a line (`:`, `-`, and `=`)\n \tand between hunks (`--`)\ndiff --git a/pretty.c b/pretty.c\nindex 73b5ead509..2dd94af886 100644\n--- a/pretty.c\n+++ b/pretty.c\n@@ -431,6 +431,52 @@ const char *show_ident_date(const struct ident_split *ident,\n \treturn show_date(date, tz, mode);\n }\n \n+static inline void strbuf_add_with_color(struct strbuf *sb, const char *color,\n+\t\t\t\t\t const char *buf, size_t buflen)\n+{\n+\tstrbuf_addstr(sb, color);\n+\tstrbuf_add(sb, buf, buflen);\n+\tif (*color)\n+\t\tstrbuf_addstr(sb, GIT_COLOR_RESET);\n+}\n+\n+static void append_line_with_color(struct strbuf *sb, struct grep_opt *opt,\n+\t\t\t\t   const char *line, size_t linelen,\n+\t\t\t\t   int color, enum grep_context ctx,\n+\t\t\t\t   enum grep_header_field field)\n+{\n+\tconst char *buf, *eol, *line_color, *match_color;\n+\tregmatch_t match;\n+\tint eflags = 0;\n+\n+\tbuf = line;\n+\teol = buf + linelen;\n+\n+\tif (!opt || !want_color(color) || opt->invert)\n+\t\tgoto end;\n+\n+\tline_color = opt->colors[GREP_COLOR_SELECTED];\n+\tmatch_color = opt->colors[GREP_COLOR_MATCH_SELECTED];\n+\n+\twhile (grep_next_match(opt, buf, eol, ctx, &match, field, eflags)) {\n+\t\tif (match.rm_so == match.rm_eo)\n+\t\t\tbreak;\n+\n+\t\tstrbuf_add_with_color(sb, line_color, buf, match.rm_so);\n+\t\tstrbuf_add_with_color(sb, match_color, buf + match.rm_so,\n+\t\t\t\t      match.rm_eo - match.rm_so);\n+\t\tbuf += match.rm_eo;\n+\t\teflags = REG_NOTBOL;\n+\t}\n+\n+\tif (eflags)\n+\t\tstrbuf_add_with_color(sb, line_color, buf, eol - buf);\n+\telse {\n+end:\n+\t\tstrbuf_add(sb, buf, eol - buf);\n+\t}\n+}\n+\n void pp_user_info(struct pretty_print_context *pp,\n \t\t  const char *what, struct strbuf *sb,\n \t\t  const char *line, const char *encoding)\n@@ -496,9 +542,26 @@ void pp_user_info(struct pretty_print_context *pp,\n \t\t\tstrbuf_addch(sb, '\\n');\n \t\tstrbuf_addf(sb, \" <%.*s>\\n\", (int)maillen, mailbuf);\n \t} else {\n-\t\tstrbuf_addf(sb, \"%s: %.*s%.*s <%.*s>\\n\", what,\n-\t\t\t    (pp->fmt == CMIT_FMT_FULLER) ? 4 : 0, \"    \",\n-\t\t\t    (int)namelen, namebuf, (int)maillen, mailbuf);\n+\t\tstruct strbuf id = STRBUF_INIT;\n+\t\tenum grep_header_field field = GREP_HEADER_FIELD_MAX;\n+\t\tstruct grep_opt *opt = pp->rev ? &pp->rev->grep_filter : NULL;\n+\n+\t\tif (!strcmp(what, \"Author\"))\n+\t\t\tfield = GREP_HEADER_AUTHOR;\n+\t\telse if (!strcmp(what, \"Commit\"))\n+\t\t\tfield = GREP_HEADER_COMMITTER;\n+\n+\t\tstrbuf_addf(sb, \"%s: \", what);\n+\t\tif (pp->fmt == CMIT_FMT_FULLER)\n+\t\t\tstrbuf_addchars(sb, ' ', 4);\n+\n+\t\tstrbuf_addf(&id, \"%.*s <%.*s>\", (int)namelen, namebuf,\n+\t\t\t    (int)maillen, mailbuf);\n+\n+\t\tappend_line_with_color(sb, opt, id.buf, id.len, pp->color,\n+\t\t\t\t       GREP_CONTEXT_HEAD, field);\n+\t\tstrbuf_addch(sb, '\\n');\n+\t\tstrbuf_release(&id);\n \t}\n \n \tswitch (pp->fmt) {\n@@ -1939,8 +2002,9 @@ static int pp_utf8_width(const char *start, const char *end)\n \treturn width;\n }\n \n-static void strbuf_add_tabexpand(struct strbuf *sb, int tabwidth,\n-\t\t\t\t const char *line, int linelen)\n+static void strbuf_add_tabexpand(struct strbuf *sb, struct grep_opt *opt,\n+\t\t\t\t int color, int tabwidth, const char *line,\n+\t\t\t\t int linelen)\n {\n \tconst char *tab;\n \n@@ -1957,7 +2021,9 @@ static void strbuf_add_tabexpand(struct strbuf *sb, int tabwidth,\n \t\t\tbreak;\n \n \t\t/* Output the data .. */\n-\t\tstrbuf_add(sb, line, tab - line);\n+\t\tappend_line_with_color(sb, opt, line, tab - line, color,\n+\t\t\t\t       GREP_CONTEXT_BODY,\n+\t\t\t\t       GREP_HEADER_FIELD_MAX);\n \n \t\t/* .. and the de-tabified tab */\n \t\tstrbuf_addchars(sb, ' ', tabwidth - (width % tabwidth));\n@@ -1972,7 +2038,8 @@ static void strbuf_add_tabexpand(struct strbuf *sb, int tabwidth,\n \t * worrying about width - there's nothing more to\n \t * align.\n \t */\n-\tstrbuf_add(sb, line, linelen);\n+\tappend_line_with_color(sb, opt, line, linelen, color, GREP_CONTEXT_BODY,\n+\t\t\t       GREP_HEADER_FIELD_MAX);\n }\n \n /*\n@@ -1984,11 +2051,16 @@ static void pp_handle_indent(struct pretty_print_context *pp,\n \t\t\t     struct strbuf *sb, int indent,\n \t\t\t     const char *line, int linelen)\n {\n+\tstruct grep_opt *opt = pp->rev ? &pp->rev->grep_filter : NULL;\n+\n \tstrbuf_addchars(sb, ' ', indent);\n \tif (pp->expand_tabs_in_log)\n-\t\tstrbuf_add_tabexpand(sb, pp->expand_tabs_in_log, line, linelen);\n+\t\tstrbuf_add_tabexpand(sb, opt, pp->color, pp->expand_tabs_in_log,\n+\t\t\t\t     line, linelen);\n \telse\n-\t\tstrbuf_add(sb, line, linelen);\n+\t\tappend_line_with_color(sb, opt, line, linelen, pp->color,\n+\t\t\t\t       GREP_CONTEXT_BODY,\n+\t\t\t\t       GREP_HEADER_FIELD_MAX);\n }\n \n static int is_mboxrd_from(const char *line, int len)\n@@ -2006,7 +2078,9 @@ void pp_remainder(struct pretty_print_context *pp,\n \t\t  struct strbuf *sb,\n \t\t  int indent)\n {\n+\tstruct grep_opt *opt = pp->rev ? &pp->rev->grep_filter : NULL;\n \tint first = 1;\n+\n \tfor (;;) {\n \t\tconst char *line = *msg_p;\n \t\tint linelen = get_one_line(line);\n@@ -2027,14 +2101,17 @@ void pp_remainder(struct pretty_print_context *pp,\n \t\tif (indent)\n \t\t\tpp_handle_indent(pp, sb, indent, line, linelen);\n \t\telse if (pp->expand_tabs_in_log)\n-\t\t\tstrbuf_add_tabexpand(sb, pp->expand_tabs_in_log,\n-\t\t\t\t\t     line, linelen);\n+\t\t\tstrbuf_add_tabexpand(sb, opt, pp->color,\n+\t\t\t\t\t     pp->expand_tabs_in_log, line,\n+\t\t\t\t\t     linelen);\n \t\telse {\n \t\t\tif (pp->fmt == CMIT_FMT_MBOXRD &&\n \t\t\t\t\tis_mboxrd_from(line, linelen))\n \t\t\t\tstrbuf_addch(sb, '>');\n \n-\t\t\tstrbuf_add(sb, line, linelen);\n+\t\t\tappend_line_with_color(sb, opt, line, linelen,\n+\t\t\t\t\t       pp->color, GREP_CONTEXT_BODY,\n+\t\t\t\t\t       GREP_HEADER_FIELD_MAX);\n \t\t}\n \t\tstrbuf_addch(sb, '\\n');\n \t}\ndiff --git a/t/t4202-log.sh b/t/t4202-log.sh\nindex 9dfead936b..3d240bba57 100755\n--- a/t/t4202-log.sh\n+++ b/t/t4202-log.sh\n@@ -449,6 +449,57 @@ test_expect_success !FAIL_PREREQS 'log with various grep.patternType configurati\n \t)\n '\n \n+test_expect_success 'log --author' '\n+\tcat >expect <<-\\EOF &&\n+\tAuthor: <BOLD;RED>A U<RESET> Thor <author@example.com>\n+\tEOF\n+\tgit log -1 --color=always --author=\"A U\" >log &&\n+\tgrep Author log >actual.raw &&\n+\ttest_decode_color <actual.raw >actual &&\n+\ttest_cmp expect actual\n+'\n+\n+test_expect_success 'log --committer' '\n+\tcat >expect <<-\\EOF &&\n+\tCommit:     C O Mitter <committer@<BOLD;RED>example<RESET>.com>\n+\tEOF\n+\tgit log -1 --color=always --pretty=fuller --committer=\"example\" >log &&\n+\tgrep \"Commit:\" log >actual.raw &&\n+\ttest_decode_color <actual.raw >actual &&\n+\ttest_cmp expect actual\n+'\n+\n+test_expect_success 'log -i --grep with color' '\n+\tcat >expect <<-\\EOF &&\n+\t    <BOLD;RED>Sec<RESET>ond\n+\t    <BOLD;RED>sec<RESET>ond\n+\tEOF\n+\tgit log --color=always -i --grep=^sec >log &&\n+\tgrep -i sec log >actual.raw &&\n+\ttest_decode_color <actual.raw >actual &&\n+\ttest_cmp expect actual\n+'\n+\n+test_expect_success '-c color.grep.selected log --grep' '\n+\tcat >expect <<-\\EOF &&\n+\t    <GREEN>th<RESET><BOLD;RED>ir<RESET><GREEN>d<RESET>\n+\tEOF\n+\tgit -c color.grep.selected=\"green\" log --color=always --grep=ir >log &&\n+\tgrep ir log >actual.raw &&\n+\ttest_decode_color <actual.raw >actual &&\n+\ttest_cmp expect actual\n+'\n+\n+test_expect_success '-c color.grep.matchSelected log --grep' '\n+\tcat >expect <<-\\EOF &&\n+\t    <BLUE>i<RESET>n<BLUE>i<RESET>t<BLUE>i<RESET>al\n+\tEOF\n+\tgit -c color.grep.matchSelected=\"blue\" log --color=always --grep=i >log &&\n+\tgrep al log >actual.raw &&\n+\ttest_decode_color <actual.raw >actual &&\n+\ttest_cmp expect actual\n+'\n+\n cat > expect <<EOF\n * Second\n * sixth\n-- \n2.33.0\n\n"},{"id":"437019","messageId":"xmqqilypu6a0.fsf@gitster.g","threadId":"56581","inReplyTo":"20210924155000.1259649-1-someguy@effective-light.com","subject":"Re: [PATCH v8 1/2] grep: refactor next_match() and match_one_pattern() for external use","fromName":"Junio C Hamano","fromEmail":"gitster@pobox.com","sentAt":"2021-09-24T19:23:35Z","receivedAt":"2021-09-24T19:23:43Z","isPatch":true,"sender":{"key":"gitster@pobox.com","avatar":"https://avatars.githubusercontent.com/u/54884?v=4"},"body":"Hamza Mahfooz <someguy@effective-light.com> writes:\n\n> These changes are made in preparation of, the colorization support for the\n> \"git log\" subcommands that, rely on regex functionality (i.e. \"--author\",\n> \"--committer\" and \"--grep\"). These changes are necessary primarily because\n> match_one_pattern() expects header lines to be prefixed, however, in\n> pretty, the prefixes are stripped from the lines because the name-email\n> pairs need to go through additional parsing, before they can be printed and\n> because next_match() doesn't handle the case of\n> \"ctx == GREP_CONTEXT_HEAD\" at all. So, teach next_match() how to handle the\n> new case and move match_one_pattern()'s core logic to\n> headless_match_one_pattern() while preserving match_one_pattern()'s uses\n> that depend on the additional processing.\n>\n> Signed-off-by: Hamza Mahfooz <someguy@effective-light.com>\n> ---\n> v5: separate grep changes from pretty changes.\n>\n> v6: rescope some variables.\n>\n> v7: export header_field[] and allow for subsequent matches on header lines\n>     in match_one_pattern().\n>\n> v8: add headless_match_one_pattern() and move header_field[] back.\n\nThis looks a lot more sensible split compared to the previous round.\n\n> ---\n>  grep.c | 83 ++++++++++++++++++++++++++++++++++++----------------------\n>  grep.h |  4 +++\n>  2 files changed, 55 insertions(+), 32 deletions(-)\n>\n> diff --git a/grep.c b/grep.c\n> index 14fe8a0fd2..e46b046638 100644\n> --- a/grep.c\n> +++ b/grep.c\n> @@ -944,37 +944,19 @@ static struct {\n>  \t{ \"reflog \", 7 },\n>  };\n>  \n> -static int match_one_pattern(struct grep_pat *p,\n> -\t\t\t     const char *bol, const char *eol,\n> -\t\t\t     enum grep_context ctx,\n> -\t\t\t     regmatch_t *pmatch, int eflags)\n> +static int headerless_match_one_pattern(struct grep_pat *p,\n> +\t\t\t\t\tconst char *bol, const char *eol,\n> +\t\t\t\t\tenum grep_context ctx,\n> +\t\t\t\t\tregmatch_t *pmatch, int eflags)\n>  {\n>  \tint hit = 0;\n>  \tconst char *start = bol;\n>  \n>  \tif ((p->token != GREP_PATTERN) &&\n> -\t    ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))\n> +\t    ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)) &&\n> +\t    ((p->token == GREP_PATTERN_BODY) != (ctx == GREP_CONTEXT_BODY)))\n\nI _think_ it makes sense to have this additional \"if looking for\nsomething in the body, do not bother if we are not in body\", but I\nwonder if that is a bugfix that has nothing to do with this topic.\n\nIn other words, even if for whatever reason we decide that it is not\nworth painting the hits in \"git log --grep=<pattern> --author=<who>\"\noutput, would the addition to this single condition to the original\ncode, with or without the refactoring, fix some existing bug?\n\nIf so, perhaps that can be a separate patch with a test that\ndemonstrates the bug fixed.  With this change mixed in, it is\nunclear if this step is pure refactoring that does not break the\nexisting callers of the code path.\n\nIf it is not a bugfix, we need to explain the reason why this\nadditional condition is necessary in the proposed log message (I am\nassuming that this change is needed to get the end result working).\n\n> +static int match_one_pattern(struct grep_pat *p,\n> +\t\t\t     const char *bol, const char *eol,\n> +\t\t\t     enum grep_context ctx, regmatch_t *pmatch,\n> +\t\t\t     int eflags)\n> +{\n> +\tconst char *field;\n> +\tsize_t len;\n> +\n> +\tif (p->token == GREP_PATTERN_HEAD) {\n> +\t\tassert(p->field < ARRAY_SIZE(header_field));\n> +\t\tfield = header_field[p->field].field;\n> +\t\tlen = header_field[p->field].len;\n> +\t\tif (strncmp(bol, field, len))\n> +\t\t\treturn 0;\n> +\t\tbol += len;\n> +\n> +\t\tswitch (p->field) {\n> +\t\tcase GREP_HEADER_AUTHOR:\n> +\t\tcase GREP_HEADER_COMMITTER:\n> +\t\t\tstrip_timestamp(bol, &eol);\n> +\t\t\tbreak;\n> +\t\tdefault:\n> +\t\t\tbreak;\n> +\t\t}\n> +\t}\n> +\n> +\treturn headerless_match_one_pattern(p, bol, eol, ctx, pmatch, eflags);\n> +}\n\nSo, match_one_pattern() after all the above changes behaves almost\nidentically for existing callers, except that it has the \"pattern\nfor body should only apply to the body text\" condition added, which\nmay affect the behaviour.\n\n> @@ -1143,7 +1155,7 @@ static int match_next_pattern(struct grep_pat *p,\n>  {\n>  \tregmatch_t match;\n>  \n> -\tif (!match_one_pattern(p, bol, eol, ctx, &match, eflags))\n> +\tif (!headerless_match_one_pattern(p, bol, eol, ctx, &match, eflags))\n>  \t\treturn 0;\n>  \tif (match.rm_so < 0 || match.rm_eo < 0)\n>  \t\treturn 0;\n\nSince this \"next\" thing is designed to be repeatedly called, we use\nthe new helper that is meant for <bol, eol> after we preprocessed\nthe header and the trailing timestamp away, which makes sense, I\nguess.  But the caller needs to do the preprocessing before it makes\nthe first call to match_next_pattern() on any given line to adjust\nbol and eol.\n\n> @@ -1158,22 +1170,28 @@ static int match_next_pattern(struct grep_pat *p,\n>  \treturn 1;\n>  }\n>  \n> -static int next_match(struct grep_opt *opt,\n> -\t\t      const char *bol, const char *eol,\n> -\t\t      enum grep_context ctx, regmatch_t *pmatch, int eflags)\n> +int grep_next_match(struct grep_opt *opt,\n> +\t\t    const char *bol, const char *eol,\n> +\t\t    enum grep_context ctx, regmatch_t *pmatch,\n> +\t\t    enum grep_header_field field, int eflags)\n>  {\n>  \tstruct grep_pat *p;\n>  \tint hit = 0;\n>  \n>  \tpmatch->rm_so = pmatch->rm_eo = -1;\n>  \tif (bol < eol) {\n> -\t\tfor (p = opt->pattern_list; p; p = p->next) {\n> +\t\tfor (p = ((ctx == GREP_CONTEXT_HEAD)\n> +\t\t\t   ? opt->header_list : opt->pattern_list);\n> +\t\t\t  p; p = p->next) {\n>  \t\t\tswitch (p->token) {\n>  \t\t\tcase GREP_PATTERN: /* atom */\n>  \t\t\tcase GREP_PATTERN_HEAD:\n>  \t\t\tcase GREP_PATTERN_BODY:\n> -\t\t\t\thit |= match_next_pattern(p, bol, eol, ctx,\n> -\t\t\t\t\t\t\t  pmatch, eflags);\n> +\t\t\t\tif ((field == GREP_HEADER_FIELD_MAX) ||\n> +\t\t\t\t    (p->field == field))\n> +\t\t\t\t\thit |= match_next_pattern(p, bol, eol,\n> +\t\t\t\t\t\t\t\t  ctx, pmatch,\n> +\t\t\t\t\t\t\t\t  eflags);\n\n... and this caller apparently does not.  It is made the\nresponsibility of the callers of grep_next_match() to adjust bol and\neol before calling it.\n\n>  \t\t\t\tbreak;\n>  \t\t\tdefault:\n>  \t\t\t\tbreak;\n> @@ -1261,7 +1279,8 @@ static void show_line(struct grep_opt *opt,\n>  \t\t\telse if (sign == '=')\n>  \t\t\t\tline_color = opt->colors[GREP_COLOR_FUNCTION];\n>  \t\t}\n> -\t\twhile (next_match(opt, bol, eol, ctx, &match, eflags)) {\n> +\t\twhile (grep_next_match(opt, bol, eol, ctx, &match,\n> +\t\t\t\t       GREP_HEADER_FIELD_MAX, eflags)) {\n\n... which is this caller, show_line(), which is the only caller of\ngrep_next_match().\n\nBut this function is not taught to strip headers and timestamp from\n<bol, eol>, either, so it is the responsibility of the callers of\nshow_line().\n\nI _think_ all the current callers of show_line() handle the blob\ncontents found by \"git grep\" and not \"git log --grep/--author\", and\nthere is no GREP_PATTERN_HEAD/GREP_PATTERN_BODY given, but I may be\nmistaken.  With the current set of callers, do we ever call\nnext_match() with a pattern with p->token set to GREP_PATTERN_HEAD\nor _BODY?  I am wondering why we even have those cases covered in\nthe switch statement in the previous hunk.\n\nmatch_one_pattern() of course must be prepared to see the HEAD and\nBODY requests because match_expr_eval() is evantually called via\ngrep_buffer() interface to implement \"git log --grep/--author\", but\nI do not think next_match() would be called in that code path.  The\nhandling of GREP_PATTERN_HEAD and GREP_PATTERN_BODY in next_match(),\nwhich I am wondering about, came from 7e8f59d5 (grep: color patterns\nin output, 2009-03-07).\n\nAnyway, let's read on.\n\n> diff --git a/grep.h b/grep.h\n> index 3cb8a83ae8..521068308e 100644\n> --- a/grep.h\n> +++ b/grep.h\n> @@ -190,6 +190,10 @@ void append_header_grep_pattern(struct grep_opt *, enum grep_header_field, const\n>  void compile_grep_patterns(struct grep_opt *opt);\n>  void free_grep_patterns(struct grep_opt *opt);\n>  int grep_buffer(struct grep_opt *opt, const char *buf, unsigned long size);\n> +int grep_next_match(struct grep_opt *opt,\n> +\t\t    const char *bol, const char *eol,\n> +\t\t    enum grep_context ctx, regmatch_t *pmatch,\n> +\t\t    enum grep_header_field field, int eflags);\n\nAs this is made external, it at least needs a comment on the\n(somewhat strange) field parameter, especially the fact that \"no,\nthis is not grepping in the header lines in a commit object\" is\nsignalled by a special GREP_HEADER_FIELD_MAX value.\n\n>  \n>  struct grep_source {\n>  \tchar *name;\n\nOther than that, looks much cleaner than the previous round.\n\nThanks.\n"},{"id":"437211","messageId":"xmqqilylmuqx.fsf@gitster.g","threadId":"56581","inReplyTo":"20210924155000.1259649-2-someguy@effective-light.com","subject":"Re: [PATCH v8 2/2] pretty: colorize pattern matches in commit messages","fromName":"Junio C Hamano","fromEmail":"gitster@pobox.com","sentAt":"2021-09-28T00:03:34Z","receivedAt":"2021-09-28T00:03:37Z","isPatch":true,"sender":{"key":"gitster@pobox.com","avatar":"https://avatars.githubusercontent.com/u/54884?v=4"},"body":"Hamza Mahfooz <someguy@effective-light.com> writes:\n\n> +static void append_line_with_color(struct strbuf *sb, struct grep_opt *opt,\n> +\t\t\t\t   const char *line, size_t linelen,\n> +\t\t\t\t   int color, enum grep_context ctx,\n> +\t\t\t\t   enum grep_header_field field)\n> +{\n> +\tconst char *buf, *eol, *line_color, *match_color;\n> +\tregmatch_t match;\n> +\tint eflags = 0;\n> +\n> +\tbuf = line;\n> +\teol = buf + linelen;\n> +\n> +\tif (!opt || !want_color(color) || opt->invert)\n> +\t\tgoto end;\n> +\n> +\tline_color = opt->colors[GREP_COLOR_SELECTED];\n> +\tmatch_color = opt->colors[GREP_COLOR_MATCH_SELECTED];\n> +\n> +\twhile (grep_next_match(opt, buf, eol, ctx, &match, field, eflags)) {\n\nSo, this expects <buf, eol> to be only payload without \"author \" or\ntimestamp, ...\n\n>  \t} else {\n> -\t\tstrbuf_addf(sb, \"%s: %.*s%.*s <%.*s>\\n\", what,\n> -\t\t\t    (pp->fmt == CMIT_FMT_FULLER) ? 4 : 0, \"    \",\n> -\t\t\t    (int)namelen, namebuf, (int)maillen, mailbuf);\n> +\t\tstruct strbuf id = STRBUF_INIT;\n> +\t\tenum grep_header_field field = GREP_HEADER_FIELD_MAX;\n> +\t\tstruct grep_opt *opt = pp->rev ? &pp->rev->grep_filter : NULL;\n> +\n> +\t\tif (!strcmp(what, \"Author\"))\n> +\t\t\tfield = GREP_HEADER_AUTHOR;\n> +\t\telse if (!strcmp(what, \"Commit\"))\n> +\t\t\tfield = GREP_HEADER_COMMITTER;\n> +\n> +\t\tstrbuf_addf(sb, \"%s: \", what);\n> +\t\tif (pp->fmt == CMIT_FMT_FULLER)\n> +\t\t\tstrbuf_addchars(sb, ' ', 4);\n> +\n> +\t\tstrbuf_addf(&id, \"%.*s <%.*s>\", (int)namelen, namebuf,\n> +\t\t\t    (int)maillen, mailbuf);\n> +\n> +\t\tappend_line_with_color(sb, opt, id.buf, id.len, pp->color,\n> +\t\t\t\t       GREP_CONTEXT_HEAD, field);\n\n... which is exactly what this caller is doing.\n\nVery nice.\n"}]}