pretty: colorize pattern matches in commit messages

The "git log" command limits its output to the commits that contain strings
matched by a pattern when the "--grep=<pattern>" option is used, but unlike
output from "git grep -e <pattern>", the matches are not highlighted,
making them harder to spot.

Teach the pretty-printer code to highlight matches from the
"--grep=<pattern>", "--author=<pattern>" and "--committer=<pattern>"
options (to view the last one, you may have to ask for --pretty=fuller).

Also, it must be noted that we are effectively greping the content twice
(because it would be a hassle to rework the existing matching code to do
a /g match and then pass it all down to the coloring code), however it only
slows down "git log --author=^H" on this repository by around 1-2%
(compared to v2.33.0), so it should be a small enough slow down to justify
the addition of the feature.

Signed-off-by: Hamza Mahfooz <someguy@effective-light.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/config/color.txt b/Documentation/config/color.txt
index e05d520a867490ce6b5388e2c48d1ce53de4e07e..91d9a9da32902216a6165535201c517ba14603e5 100644 (file)
--- a/Documentation/config/color.txt
+++ b/Documentation/config/color.txt
@@ -104,9 +104,12 @@ color.grep.<slot>::
 `matchContext`;;
        matching text in context lines
 `matchSelected`;;
-       matching text in selected lines
+       matching text in selected lines. Also, used to customize the following
+       linkgit:git-log[1] subcommands: `--grep`, `--author` and `--committer`.
 `selected`;;
-       non-matching text in selected lines
+       non-matching text in selected lines. Also, used to customize the
+       following linkgit:git-log[1] subcommands: `--grep`, `--author` and
+       `--committer`.
 `separator`;;
        separators between fields on a line (`:`, `-`, and `=`)
        and between hunks (`--`)

diff --git a/pretty.c b/pretty.c
index 73b5ead5099d3efdb3e1999865ab868da5053ea6..2dd94af88678f47aa16e2076252ce8988a313745 100644 (file)
--- a/pretty.c
+++ b/pretty.c
@@ -431,6 +431,52 @@ const char *show_ident_date(const struct ident_split *ident,
        return show_date(date, tz, mode);
 }
 
+static inline void strbuf_add_with_color(struct strbuf *sb, const char *color,
+                                        const char *buf, size_t buflen)
+{
+       strbuf_addstr(sb, color);
+       strbuf_add(sb, buf, buflen);
+       if (*color)
+               strbuf_addstr(sb, GIT_COLOR_RESET);
+}
+
+static void append_line_with_color(struct strbuf *sb, struct grep_opt *opt,
+                                  const char *line, size_t linelen,
+                                  int color, enum grep_context ctx,
+                                  enum grep_header_field field)
+{
+       const char *buf, *eol, *line_color, *match_color;
+       regmatch_t match;
+       int eflags = 0;
+
+       buf = line;
+       eol = buf + linelen;
+
+       if (!opt || !want_color(color) || opt->invert)
+               goto end;
+
+       line_color = opt->colors[GREP_COLOR_SELECTED];
+       match_color = opt->colors[GREP_COLOR_MATCH_SELECTED];
+
+       while (grep_next_match(opt, buf, eol, ctx, &match, field, eflags)) {
+               if (match.rm_so == match.rm_eo)
+                       break;
+
+               strbuf_add_with_color(sb, line_color, buf, match.rm_so);
+               strbuf_add_with_color(sb, match_color, buf + match.rm_so,
+                                     match.rm_eo - match.rm_so);
+               buf += match.rm_eo;
+               eflags = REG_NOTBOL;
+       }
+
+       if (eflags)
+               strbuf_add_with_color(sb, line_color, buf, eol - buf);
+       else {
+end:
+               strbuf_add(sb, buf, eol - buf);
+       }
+}
+
 void pp_user_info(struct pretty_print_context *pp,
                  const char *what, struct strbuf *sb,
                  const char *line, const char *encoding)
@@ -496,9 +542,26 @@ void pp_user_info(struct pretty_print_context *pp,
                        strbuf_addch(sb, '\n');
                strbuf_addf(sb, " <%.*s>\n", (int)maillen, mailbuf);
        } else {
-               strbuf_addf(sb, "%s: %.*s%.*s <%.*s>\n", what,
-                           (pp->fmt == CMIT_FMT_FULLER) ? 4 : 0, "    ",
-                           (int)namelen, namebuf, (int)maillen, mailbuf);
+               struct strbuf id = STRBUF_INIT;
+               enum grep_header_field field = GREP_HEADER_FIELD_MAX;
+               struct grep_opt *opt = pp->rev ? &pp->rev->grep_filter : NULL;
+
+               if (!strcmp(what, "Author"))
+                       field = GREP_HEADER_AUTHOR;
+               else if (!strcmp(what, "Commit"))
+                       field = GREP_HEADER_COMMITTER;
+
+               strbuf_addf(sb, "%s: ", what);
+               if (pp->fmt == CMIT_FMT_FULLER)
+                       strbuf_addchars(sb, ' ', 4);
+
+               strbuf_addf(&id, "%.*s <%.*s>", (int)namelen, namebuf,
+                           (int)maillen, mailbuf);
+
+               append_line_with_color(sb, opt, id.buf, id.len, pp->color,
+                                      GREP_CONTEXT_HEAD, field);
+               strbuf_addch(sb, '\n');
+               strbuf_release(&id);
        }
 
        switch (pp->fmt) {
@@ -1939,8 +2002,9 @@ static int pp_utf8_width(const char *start, const char *end)
        return width;
 }
 
-static void strbuf_add_tabexpand(struct strbuf *sb, int tabwidth,
-                                const char *line, int linelen)
+static void strbuf_add_tabexpand(struct strbuf *sb, struct grep_opt *opt,
+                                int color, int tabwidth, const char *line,
+                                int linelen)
 {
        const char *tab;
 
@@ -1957,7 +2021,9 @@ static void strbuf_add_tabexpand(struct strbuf *sb, int tabwidth,
                        break;
 
                /* Output the data .. */
-               strbuf_add(sb, line, tab - line);
+               append_line_with_color(sb, opt, line, tab - line, color,
+                                      GREP_CONTEXT_BODY,
+                                      GREP_HEADER_FIELD_MAX);
 
                /* .. and the de-tabified tab */
                strbuf_addchars(sb, ' ', tabwidth - (width % tabwidth));
@@ -1972,7 +2038,8 @@ static void strbuf_add_tabexpand(struct strbuf *sb, int tabwidth,
         * worrying about width - there's nothing more to
         * align.
         */
-       strbuf_add(sb, line, linelen);
+       append_line_with_color(sb, opt, line, linelen, color, GREP_CONTEXT_BODY,
+                              GREP_HEADER_FIELD_MAX);
 }
 
 /*
@@ -1984,11 +2051,16 @@ static void pp_handle_indent(struct pretty_print_context *pp,
                             struct strbuf *sb, int indent,
                             const char *line, int linelen)
 {
+       struct grep_opt *opt = pp->rev ? &pp->rev->grep_filter : NULL;
+
        strbuf_addchars(sb, ' ', indent);
        if (pp->expand_tabs_in_log)
-               strbuf_add_tabexpand(sb, pp->expand_tabs_in_log, line, linelen);
+               strbuf_add_tabexpand(sb, opt, pp->color, pp->expand_tabs_in_log,
+                                    line, linelen);
        else
-               strbuf_add(sb, line, linelen);
+               append_line_with_color(sb, opt, line, linelen, pp->color,
+                                      GREP_CONTEXT_BODY,
+                                      GREP_HEADER_FIELD_MAX);
 }
 
 static int is_mboxrd_from(const char *line, int len)
@@ -2006,7 +2078,9 @@ void pp_remainder(struct pretty_print_context *pp,
                  struct strbuf *sb,
                  int indent)
 {
+       struct grep_opt *opt = pp->rev ? &pp->rev->grep_filter : NULL;
        int first = 1;
+
        for (;;) {
                const char *line = *msg_p;
                int linelen = get_one_line(line);
@@ -2027,14 +2101,17 @@ void pp_remainder(struct pretty_print_context *pp,
                if (indent)
                        pp_handle_indent(pp, sb, indent, line, linelen);
                else if (pp->expand_tabs_in_log)
-                       strbuf_add_tabexpand(sb, pp->expand_tabs_in_log,
-                                            line, linelen);
+                       strbuf_add_tabexpand(sb, opt, pp->color,
+                                            pp->expand_tabs_in_log, line,
+                                            linelen);
                else {
                        if (pp->fmt == CMIT_FMT_MBOXRD &&
                                        is_mboxrd_from(line, linelen))
                                strbuf_addch(sb, '>');
 
-                       strbuf_add(sb, line, linelen);
+                       append_line_with_color(sb, opt, line, linelen,
+                                              pp->color, GREP_CONTEXT_BODY,
+                                              GREP_HEADER_FIELD_MAX);
                }
                strbuf_addch(sb, '\n');
        }

diff --git a/t/t4202-log.sh b/t/t4202-log.sh
index 9dfead936b7b5be7e0c5a16c2deb90837d7c96d4..3d240bba57c234cb384d78c9bd9971517bb75c1c 100755 (executable)
--- a/t/t4202-log.sh
+++ b/t/t4202-log.sh
@@ -449,6 +449,57 @@ test_expect_success !FAIL_PREREQS 'log with various grep.patternType configurati
        )
 '
 
+test_expect_success 'log --author' '
+       cat >expect <<-\EOF &&
+       Author: <BOLD;RED>A U<RESET> Thor <author@example.com>
+       EOF
+       git log -1 --color=always --author="A U" >log &&
+       grep Author log >actual.raw &&
+       test_decode_color <actual.raw >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'log --committer' '
+       cat >expect <<-\EOF &&
+       Commit:     C O Mitter <committer@<BOLD;RED>example<RESET>.com>
+       EOF
+       git log -1 --color=always --pretty=fuller --committer="example" >log &&
+       grep "Commit:" log >actual.raw &&
+       test_decode_color <actual.raw >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success 'log -i --grep with color' '
+       cat >expect <<-\EOF &&
+           <BOLD;RED>Sec<RESET>ond
+           <BOLD;RED>sec<RESET>ond
+       EOF
+       git log --color=always -i --grep=^sec >log &&
+       grep -i sec log >actual.raw &&
+       test_decode_color <actual.raw >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success '-c color.grep.selected log --grep' '
+       cat >expect <<-\EOF &&
+           <GREEN>th<RESET><BOLD;RED>ir<RESET><GREEN>d<RESET>
+       EOF
+       git -c color.grep.selected="green" log --color=always --grep=ir >log &&
+       grep ir log >actual.raw &&
+       test_decode_color <actual.raw >actual &&
+       test_cmp expect actual
+'
+
+test_expect_success '-c color.grep.matchSelected log --grep' '
+       cat >expect <<-\EOF &&
+           <BLUE>i<RESET>n<BLUE>i<RESET>t<BLUE>i<RESET>al
+       EOF
+       git -c color.grep.matchSelected="blue" log --color=always --grep=i >log &&
+       grep al log >actual.raw &&
+       test_decode_color <actual.raw >actual &&
+       test_cmp expect actual
+'
+
 cat > expect <<EOF
 * Second
 * sixth