# [PATCH v4 1/3] diff: add --word-diff option that generalizes --color-words

11 messages from 2010-04-14 to 2010-04-19. Participants: Thomas Rast, Junio C Hamano, Jens Lehmann, Paul Mackerras.
Thread: https://gitlist.dev/t/23459

## Thomas Rast, 2010-04-14 15:59

Subject: [PATCH v4 0/3] git-diff --word-diff/gitk --color-words
Message-ID: <cover.1271260308.git.trast@student.ethz.ch>
URL: https://gitlist.dev/e/cover.1271260308.git.trast%40student.ethz.ch
In-Reply-To: <7v8w8sljjr.fsf@alter.siamese.dyndns.org>

```
This merely addresses Junio's comments on 1/3 of the last round, since
I haven't heard anything about the gitk patches.


Thomas Rast (3):
  diff: add --word-diff option that generalizes --color-words
  gitk: do not parse "  >" context as submodule change
  gitk: add the equivalent of diff --color-words

```

## Thomas Rast, 2010-04-14 15:59

Subject: [PATCH v4 1/3] diff: add --word-diff option that generalizes --color-words
Message-ID: <9a2b460ea5db47154623386638e883f749c4ee35.1271260308.git.trast@student.ethz.ch>
URL: https://gitlist.dev/e/9a2b460ea5db47154623386638e883f749c4ee35.1271260308.git.trast%40student.ethz.ch
In-Reply-To: <cover.1271260308.git.trast@student.ethz.ch>

```
This teaches the --color-words engine a more general interface that
supports two new modes:

* --word-diff=plain, inspired by the 'wdiff' utility (most similar to
  'wdiff -n <old> <new>'): uses delimiters [-removed-] and {+added+}

* --word-diff=porcelain, which generates an ad-hoc machine readable
  format:
  - each diff unit is prefixed by [-+ ] and terminated by newline as
    in unified diff
  - newlines in the input are output as a line consisting only of a
    tilde '~'

Both of these formats still support color if it is enabled, using it
to highlight the differences.  --color-words becomes a synonym for
--word-diff=color, which is the color-only format.  Also adds some
compatibility/convenience options.

Thanks to Junio C Hamano and Miles Bader for good ideas.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 Documentation/diff-options.txt  |   40 ++++++++++-
 Documentation/gitattributes.txt |    2 +-
 color.c                         |   28 --------
 color.h                         |    1 -
 diff.c                          |  139 +++++++++++++++++++++++++++++++++-----
 diff.h                          |   10 +++-
 t/t4034-diff-words.sh           |  122 ++++++++++++++++++++++++++++++++++
 7 files changed, 288 insertions(+), 54 deletions(-)

diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index 60e922e..a616ca5 100644
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -126,11 +126,39 @@ any of those replacements occurred.
 	gives the default to color output.
 	Same as `--color=never`.
 
---color-words[=<regex>]::
-	Show colored word diff, i.e., color words which have changed.
-	By default, words are separated by whitespace.
+--word-diff[=<mode>]::
+	Show a word diff, using the <mode> to delimit changed words.
+	By default, words are delimited by whitespace; see
+	`--word-diff-regex` below.  The <mode> defaults to 'plain', and
+	must be one of:
++
+--
+color::
+	Highlight changed words using only colors.  Implies `--color`.
+plain::
+	Show words as `[-removed-]` and `{+added+}`.  Makes no
+	attempts to escape the delimiters if they appear in the input,
+	so the output may be ambiguous.
+porcelain::
+	Use a special line-based format intended for script
+	consumption.  Added/removed/unchanged runs are printed in the
+	usual unified diff format, starting with a `+`/`-`/` `
+	character at the beginning of the line and extending to the
+	end of the line.  Newlines in the input are represented by a
+	tilde `~` on a line of its own.
+none::
+	Disable word diff again.
+--
++
+Note that despite the name of the first mode, color is used to
+highlight the changed parts in all modes if enabled.
+
+--word-diff-regex=<regex>::
+	Use <regex> to decide what a word is, instead of considering
+	runs of non-whitespace to be a word.  Also implies
+	`--word-diff` unless it was already enabled.
 +
-When a <regex> is specified, every non-overlapping match of the
+Every non-overlapping match of the
 <regex> is considered a word.  Anything between these matches is
 considered whitespace and ignored(!) for the purposes of finding
 differences.  You may want to append `|[^[:space:]]` to your regular
@@ -142,6 +170,10 @@ The regex can also be set via a diff driver or configuration option, see
 linkgit:gitattributes[1] or linkgit:git-config[1].  Giving it explicitly
 overrides any diff driver or configuration setting.  Diff drivers
 override configuration settings.
+
+--color-words[=<regex>]::
+	Equivalent to `--word-diff=color` plus (if a regex was
+	specified) `--word-diff-regex=<regex>`.
 endif::git-format-patch[]
 
 --no-renames::
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index a8500d1..0523a57 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -360,7 +360,7 @@ patterns are available:
 Customizing word diff
 ^^^^^^^^^^^^^^^^^^^^^
 
-You can customize the rules that `git diff --color-words` uses to
+You can customize the rules that `git diff --word-diff` uses to
 split words in a line, by specifying an appropriate regular expression
 in the "diff.*.wordRegex" configuration variable.  For example, in TeX
 a backslash followed by a sequence of letters forms a command, but
diff --git a/color.c b/color.c
index bcf4e2c..1b00554 100644
--- a/color.c
+++ b/color.c
@@ -211,31 +211,3 @@ int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
 	va_end(args);
 	return r;
 }
-
-/*
- * This function splits the buffer by newlines and colors the lines individually.
- *
- * Returns 0 on success.
- */
-int color_fwrite_lines(FILE *fp, const char *color,
-		size_t count, const char *buf)
-{
-	if (!*color)
-		return fwrite(buf, count, 1, fp) != 1;
-	while (count) {
-		char *p = memchr(buf, '\n', count);
-		if (p != buf && (fputs(color, fp) < 0 ||
-				fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
-				fputs(GIT_COLOR_RESET, fp) < 0))
-			return -1;
-		if (!p)
-			return 0;
-		if (fputc('\n', fp) < 0)
-			return -1;
-		count -= p + 1 - buf;
-		buf = p + 1;
-	}
-	return 0;
-}
-
-
diff --git a/color.h b/color.h
index 5c264b0..03ca064 100644
--- a/color.h
+++ b/color.h
@@ -61,6 +61,5 @@
 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...);
 __attribute__((format (printf, 3, 4)))
 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...);
-int color_fwrite_lines(FILE *fp, const char *color, size_t count, const char *buf);
 
 #endif /* COLOR_H */
diff --git a/diff.c b/diff.c
index 7effdac..f587b83 100644
--- a/diff.c
+++ b/diff.c
@@ -560,16 +560,68 @@ static void diff_words_append(char *line, unsigned long len,
 	buffer->text.ptr[buffer->text.size] = '\0';
 }
 
+struct diff_words_style_elem
+{
+	const char *prefix;
+	const char *suffix;
+	const char *color; /* NULL; filled in by the setup code if
+			    * color is enabled */
+};
+
+struct diff_words_style
+{
+	enum diff_words_type type;
+	struct diff_words_style_elem new, old, ctx;
+	const char *newline;
+};
+
+struct diff_words_style diff_words_styles[] = {
+	{ DIFF_WORDS_PORCELAIN, {"+", "\n"}, {"-", "\n"}, {" ", "\n"}, "~\n" },
+	{ DIFF_WORDS_PLAIN, {"{+", "+}"}, {"[-", "-]"}, {"", ""}, "\n" },
+	{ DIFF_WORDS_COLOR, {"", ""}, {"", ""}, {"", ""}, "\n" }
+};
+
 struct diff_words_data {
 	struct diff_words_buffer minus, plus;
 	const char *current_plus;
 	FILE *file;
 	regex_t *word_regex;
+	enum diff_words_type type;
+	struct diff_words_style *style;
 };
 
+static int fn_out_diff_words_write_helper(FILE *fp,
+					  struct diff_words_style_elem *st_el,
+					  const char *newline,
+					  size_t count, const char *buf)
+{
+	while (count) {
+		char *p = memchr(buf, '\n', count);
+		if (p != buf) {
+			if (st_el->color && fputs(st_el->color, fp) < 0)
+				return -1;
+			if (fputs(st_el->prefix, fp) < 0 ||
+			    fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
+			    fputs(st_el->suffix, fp) < 0)
+				return -1;
+			if (st_el->color && *st_el->color
+			    && fputs(GIT_COLOR_RESET, fp) < 0)
+				return -1;
+		}
+		if (!p)
+			return 0;
+		if (fputs(newline, fp) < 0)
+			return -1;
+		count -= p + 1 - buf;
+		buf = p + 1;
+	}
+	return 0;
+}
+
 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 {
 	struct diff_words_data *diff_words = priv;
+	struct diff_words_style *style = diff_words->style;
 	int minus_first, minus_len, plus_first, plus_len;
 	const char *minus_begin, *minus_end, *plus_begin, *plus_end;
 
@@ -593,16 +645,17 @@ static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 		plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
 
 	if (diff_words->current_plus != plus_begin)
-		fwrite(diff_words->current_plus,
-				plus_begin - diff_words->current_plus, 1,
-				diff_words->file);
+		fn_out_diff_words_write_helper(diff_words->file,
+				&style->ctx, style->newline,
+				plus_begin - diff_words->current_plus,
+				diff_words->current_plus);
 	if (minus_begin != minus_end)
-		color_fwrite_lines(diff_words->file,
-				diff_get_color(1, DIFF_FILE_OLD),
+		fn_out_diff_words_write_helper(diff_words->file,
+				&style->old, style->newline,
 				minus_end - minus_begin, minus_begin);
 	if (plus_begin != plus_end)
-		color_fwrite_lines(diff_words->file,
-				diff_get_color(1, DIFF_FILE_NEW),
+		fn_out_diff_words_write_helper(diff_words->file,
+				&style->new, style->newline,
 				plus_end - plus_begin, plus_begin);
 
 	diff_words->current_plus = plus_end;
@@ -685,11 +738,12 @@ static void diff_words_show(struct diff_words_data *diff_words)
 	xdemitconf_t xecfg;
 	xdemitcb_t ecb;
 	mmfile_t minus, plus;
+	struct diff_words_style *style = diff_words->style;
 
 	/* special case: only removal */
 	if (!diff_words->plus.text.size) {
-		color_fwrite_lines(diff_words->file,
-			diff_get_color(1, DIFF_FILE_OLD),
+		fn_out_diff_words_write_helper(diff_words->file,
+			&style->old, style->newline,
 			diff_words->minus.text.size, diff_words->minus.text.ptr);
 		diff_words->minus.text.size = 0;
 		return;
@@ -710,10 +764,10 @@ static void diff_words_show(struct diff_words_data *diff_words)
 	free(plus.ptr);
 	if (diff_words->current_plus != diff_words->plus.text.ptr +
 			diff_words->plus.text.size)
-		fwrite(diff_words->current_plus,
+		fn_out_diff_words_write_helper(diff_words->file,
+			&style->ctx, style->newline,
 			diff_words->plus.text.ptr + diff_words->plus.text.size
-			- diff_words->current_plus, 1,
-			diff_words->file);
+			- diff_words->current_plus, diff_words->current_plus);
 	diff_words->minus.text.size = diff_words->plus.text.size = 0;
 }
 
@@ -825,6 +879,9 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 
 	if (len < 1) {
 		emit_line(ecbdata->file, reset, reset, line, len);
+		if (ecbdata->diff_words
+		    && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
+			fputs("~\n", ecbdata->file);
 		return;
 	}
 
@@ -839,9 +896,13 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 			return;
 		}
 		diff_words_flush(ecbdata);
-		line++;
-		len--;
-		emit_line(ecbdata->file, plain, reset, line, len);
+		if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
+			emit_line(ecbdata->file, plain, reset, line, len);
+			fputs("~\n", ecbdata->file);
+		} else {
+			/* don't print the prefix character */
+			emit_line(ecbdata->file, plain, reset, line+1, len-1);
+		}
 		return;
 	}
 
@@ -1739,10 +1800,13 @@ static void builtin_diff(const char *name_a,
 			xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
 		else if (!prefixcmp(diffopts, "-u"))
 			xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
-		if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
+		if (o->word_diff) {
+			int i;
+
 			ecbdata.diff_words =
 				xcalloc(1, sizeof(struct diff_words_data));
 			ecbdata.diff_words->file = o->file;
+			ecbdata.diff_words->type = o->word_diff;
 			if (!o->word_regex)
 				o->word_regex = userdiff_word_regex(one);
 			if (!o->word_regex)
@@ -1758,10 +1822,23 @@ static void builtin_diff(const char *name_a,
 					die ("Invalid regular expression: %s",
 							o->word_regex);
 			}
+			for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
+				if (o->word_diff == diff_words_styles[i].type) {
+					ecbdata.diff_words->style =
+						&diff_words_styles[i];
+					break;
+				}
+			}
+			if (DIFF_OPT_TST(o, COLOR_DIFF)) {
+				struct diff_words_style *st = ecbdata.diff_words->style;
+				st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
+				st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
+				st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
+			}
 		}
 		xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
 			      &xpp, &xecfg, &ecb);
-		if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
+		if (o->word_diff)
 			free_diff_words_data(&ecbdata);
 		if (textconv_one)
 			free(mf1.ptr);
@@ -2830,13 +2907,37 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		DIFF_OPT_CLR(options, COLOR_DIFF);
 	else if (!strcmp(arg, "--color-words")) {
 		DIFF_OPT_SET(options, COLOR_DIFF);
-		DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
+		options->word_diff = DIFF_WORDS_COLOR;
 	}
 	else if (!prefixcmp(arg, "--color-words=")) {
 		DIFF_OPT_SET(options, COLOR_DIFF);
-		DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
+		options->word_diff = DIFF_WORDS_COLOR;
 		options->word_regex = arg + 14;
 	}
+	else if (!strcmp(arg, "--word-diff")) {
+		if (options->word_diff == DIFF_WORDS_NONE)
+			options->word_diff = DIFF_WORDS_PLAIN;
+	}
+	else if (!prefixcmp(arg, "--word-diff=")) {
+		const char *type = arg + 12;
+		if (!strcmp(type, "plain"))
+			options->word_diff = DIFF_WORDS_PLAIN;
+		else if (!strcmp(type, "color")) {
+			DIFF_OPT_SET(options, COLOR_DIFF);
+			options->word_diff = DIFF_WORDS_COLOR;
+		}
+		else if (!strcmp(type, "porcelain"))
+			options->word_diff = DIFF_WORDS_PORCELAIN;
+		else if (!strcmp(type, "none"))
+			options->word_diff = DIFF_WORDS_NONE;
+		else
+			die("bad --word-diff argument: %s", type);
+	}
+	else if (!prefixcmp(arg, "--word-diff-regex=")) {
+		if (options->word_diff == DIFF_WORDS_NONE)
+			options->word_diff = DIFF_WORDS_PLAIN;
+		options->word_regex = arg + 18;
+	}
 	else if (!strcmp(arg, "--exit-code"))
 		DIFF_OPT_SET(options, EXIT_WITH_STATUS);
 	else if (!strcmp(arg, "--quiet"))
diff --git a/diff.h b/diff.h
index 6a71013..9ace08c 100644
--- a/diff.h
+++ b/diff.h
@@ -54,7 +54,7 @@ typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
 #define DIFF_OPT_FIND_COPIES_HARDER  (1 <<  6)
 #define DIFF_OPT_FOLLOW_RENAMES      (1 <<  7)
 #define DIFF_OPT_COLOR_DIFF          (1 <<  8)
-#define DIFF_OPT_COLOR_DIFF_WORDS    (1 <<  9)
+/* (1 <<  9) unused */
 #define DIFF_OPT_HAS_CHANGES         (1 << 10)
 #define DIFF_OPT_QUICK               (1 << 11)
 #define DIFF_OPT_NO_INDEX            (1 << 12)
@@ -79,6 +79,13 @@ typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
 #define DIFF_XDL_SET(opts, flag)    ((opts)->xdl_opts |= XDF_##flag)
 #define DIFF_XDL_CLR(opts, flag)    ((opts)->xdl_opts &= ~XDF_##flag)
 
+enum diff_words_type {
+	DIFF_WORDS_NONE = 0,
+	DIFF_WORDS_PORCELAIN,
+	DIFF_WORDS_PLAIN,
+	DIFF_WORDS_COLOR
+};
+
 struct diff_options {
 	const char *filter;
 	const char *orderfile;
@@ -108,6 +115,7 @@ struct diff_options {
 	int stat_width;
 	int stat_name_width;
 	const char *word_regex;
+	enum diff_words_type word_diff;
 
 	/* this is set by diffcore for DIFF_FORMAT_PATCH */
 	int found_changes;
diff --git a/t/t4034-diff-words.sh b/t/t4034-diff-words.sh
index 2e2e103..6f7548c 100755
--- a/t/t4034-diff-words.sh
+++ b/t/t4034-diff-words.sh
@@ -55,6 +55,93 @@ test_expect_success 'word diff with runs of whitespace' '
 
 '
 
+test_expect_success '--word-diff=color' '
+
+	word_diff --word-diff=color
+
+'
+
+test_expect_success '--color --word-diff=color' '
+
+	word_diff --color --word-diff=color
+
+'
+
+sed 's/#.*$//' > expect <<EOF
+diff --git a/pre b/post
+index 330b04f..5ed8eff 100644
+--- a/pre
++++ b/post
+@@ -1,3 +1,7 @@
+-h(4)
++h(4),hh[44]
+~
+ # significant space
+~
+ a = b + c
+~
+~
++aa = a
+~
+~
++aeff = aeff * ( aaa )
+~
+EOF
+
+test_expect_success '--word-diff=porcelain' '
+
+	word_diff --word-diff=porcelain
+
+'
+
+cat > expect <<EOF
+diff --git a/pre b/post
+index 330b04f..5ed8eff 100644
+--- a/pre
++++ b/post
+@@ -1,3 +1,7 @@
+[-h(4)-]{+h(4),hh[44]+}
+
+a = b + c
+
+{+aa = a+}
+
+{+aeff = aeff * ( aaa )+}
+EOF
+
+test_expect_success '--word-diff=plain' '
+
+	word_diff --word-diff=plain
+
+'
+
+test_expect_success '--word-diff=plain --no-color' '
+
+	word_diff --word-diff=plain --no-color
+
+'
+
+cat > expect <<EOF
+<WHITE>diff --git a/pre b/post<RESET>
+<WHITE>index 330b04f..5ed8eff 100644<RESET>
+<WHITE>--- a/pre<RESET>
+<WHITE>+++ b/post<RESET>
+<CYAN>@@ -1,3 +1,7 @@<RESET>
+<RED>[-h(4)-]<RESET><GREEN>{+h(4),hh[44]+}<RESET>
+
+a = b + c<RESET>
+
+<GREEN>{+aa = a+}<RESET>
+
+<GREEN>{+aeff = aeff * ( aaa )+}<RESET>
+EOF
+
+test_expect_success '--word-diff=plain --color' '
+
+	word_diff --word-diff=plain --color
+
+'
+
 cat > expect <<\EOF
 <WHITE>diff --git a/pre b/post<RESET>
 <WHITE>index 330b04f..5ed8eff 100644<RESET>
@@ -143,6 +230,25 @@ test_expect_success 'command-line overrides config' '
 	word_diff --color-words="[a-z]+"
 '
 
+cat > expect <<\EOF
+<WHITE>diff --git a/pre b/post<RESET>
+<WHITE>index 330b04f..5ed8eff 100644<RESET>
+<WHITE>--- a/pre<RESET>
+<WHITE>+++ b/post<RESET>
+<CYAN>@@ -1,3 +1,7 @@<RESET>
+h(4),<GREEN>{+hh+}<RESET>[44]
+
+a = b + c<RESET>
+
+<GREEN>{+aa = a+}<RESET>
+
+<GREEN>{+aeff = aeff * ( aaa+}<RESET> )
+EOF
+
+test_expect_success 'command-line overrides config: --word-diff-regex' '
+	word_diff --color --word-diff-regex="[a-z]+"
+'
+
 cp expect.non-whitespace-is-word expect
 
 test_expect_success '.gitattributes override config' '
@@ -209,4 +315,20 @@ test_expect_success 'test when words are only removed at the end' '
 
 '
 
+cat > expect <<\EOF
+diff --git a/pre b/post
+index 289cb9d..2d06f37 100644
+--- a/pre
++++ b/post
+@@ -1 +1 @@
+-(:
++(
+EOF
+
+test_expect_success '--word-diff=none' '
+
+	word_diff --word-diff=plain --word-diff=none
+
+'
+
 test_done
-- 
1.7.1.rc1.260.g41ab89

```

## Thomas Rast, 2010-04-14 15:59

Subject: [PATCH v4 2/3] gitk: do not parse " >" context as submodule change
Message-ID: <5531510bfb94997f729a894a0b5a3158177a9add.1271260308.git.trast@student.ethz.ch>
URL: https://gitlist.dev/e/5531510bfb94997f729a894a0b5a3158177a9add.1271260308.git.trast%40student.ethz.ch
In-Reply-To: <cover.1271260308.git.trast@student.ethz.ch>

```
Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
at the beginning of a line in the submodule code even if we're in the
diff text section and the lines should be treated as context.

Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
case, and move the "  >"/"  <" specific code inside the $diffinhdr
test.  The existing code will set $diffinhdr to 0 when it hits a
"+++", so that it is always 0 when we can hit a context line.
---
 gitk |   16 ++++++++++------
 1 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/gitk b/gitk
index 1f36a3e..7b8799e 100755
--- a/gitk
+++ b/gitk
@@ -7688,12 +7688,8 @@ proc getblobdiffline {bdf ids} {
 	    lappend ctext_file_lines $fname
 	    makediffhdr $fname $ids
 	    $ctext insert end "\n$line\n" filesep
-	} elseif {![string compare -length 3 "  >" $line]} {
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" dresult
-	} elseif {![string compare -length 3 "  <" $line]} {
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" d0
+	    # pretend we're in a file header to correctly parse "  [><]"
+	    set diffinhdr 1
 	} elseif {$diffinhdr} {
 	    if {![string compare -length 12 "rename from " $line]} {
 		set fname [string range $line [expr 6 + [string first " from " $line] ] end]
@@ -7712,6 +7708,14 @@ proc getblobdiffline {bdf ids} {
 		    set fname [lindex $fname 0]
 		}
 		makediffhdr $fname $ids
+	    } elseif {![string compare -length 3 "  >" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" dresult
+		continue
+	    } elseif {![string compare -length 3 "  <" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" d0
+		continue
 	    } elseif {[string compare -length 3 $line "---"] == 0} {
 		# do nothing
 		continue
-- 
1.7.1.rc1.260.g41ab89

```

## Thomas Rast, 2010-04-14 15:59

Subject: [PATCH v4 3/3] gitk: add the equivalent of diff --color-words
Message-ID: <bc720738f918f0523842b3839b7e611c453b5241.1271260308.git.trast@student.ethz.ch>
URL: https://gitlist.dev/e/bc720738f918f0523842b3839b7e611c453b5241.1271260308.git.trast%40student.ethz.ch
In-Reply-To: <cover.1271260308.git.trast@student.ethz.ch>

```
Use the newly added 'diff --word-diff=porcelain' to teach gitk a
color-words mode, with two different modes analogous to the
--word-diff=plain and --word-diff=color settings.  These are selected
by a dropdown box.

As an extra twist, automatically enable this word-diff support when
the user mentions a word-diff related option on the command line.
These options were previously ignored because they would break diff
parsing.

Both of these features are only enabled if we have a version of git
that supports --word-diff=porcelain, tentatively set to 1.7.2.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 gitk |   64 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/gitk b/gitk
index 7b8799e..f2a1eb7 100755
--- a/gitk
+++ b/gitk
@@ -131,6 +131,7 @@ proc unmerged_files {files} {
 
 proc parseviewargs {n arglist} {
     global vdatemode vmergeonly vflags vdflags vrevs vfiltered vorigargs env
+    global worddiff git_version
 
     set vdatemode($n) 0
     set vmergeonly($n) 0
@@ -168,7 +169,7 @@ proc parseviewargs {n arglist} {
 		lappend diffargs $arg
 	    }
 	    "--raw" - "--patch-with-raw" - "--patch-with-stat" -
-	    "--name-only" - "--name-status" - "--color" - "--color-words" -
+	    "--name-only" - "--name-status" - "--color" -
 	    "--log-size" - "--pretty=*" - "--decorate" - "--abbrev-commit" -
 	    "--cc" - "-z" - "--header" - "--parents" - "--boundary" -
 	    "--no-color" - "-g" - "--walk-reflogs" - "--no-walk" -
@@ -177,6 +178,18 @@ proc parseviewargs {n arglist} {
 		# These cause our parsing of git log's output to fail, or else
 		# they're options we want to set ourselves, so ignore them.
 	    }
+	    "--color-words*" - "--word-diff=color" {
+		# These trigger a word diff in the console interface,
+		# so help the user by enabling our own support
+		if {[package vcompare $git_version "1.7.2"] >= 0} {
+		    set worddiff [mc "Color words"]
+		}
+	    }
+	    "--word-diff*" {
+		if {[package vcompare $git_version "1.7.2"] >= 0} {
+		    set worddiff [mc "Markup words"]
+		}
+	    }
 	    "--stat=*" - "--numstat" - "--shortstat" - "--summary" -
 	    "--check" - "--exit-code" - "--quiet" - "--topo-order" -
 	    "--full-history" - "--dense" - "--sparse" -
@@ -1967,6 +1980,8 @@ proc makewindow {} {
     global fprogitem fprogcoord lastprogupdate progupdatepending
     global rprogitem rprogcoord rownumsel numcommits
     global have_tk85 use_ttk NS
+    global git_version
+    global worddiff
 
     # The "mc" arguments here are purely so that xgettext
     # sees the following string as needing to be translated
@@ -2240,6 +2255,15 @@ proc makewindow {} {
     ${NS}::checkbutton .bleft.mid.ignspace -text [mc "Ignore space change"] \
 	-command changeignorespace -variable ignorespace
     pack .bleft.mid.ignspace -side left -padx 5
+
+    set worddiff [mc "Line diff"]
+    if {[package vcompare $git_version "1.7.2"] >= 0} {
+	makedroplist .bleft.mid.worddiff worddiff [mc "Line diff"] \
+	    [mc "Markup words"] [mc "Color words"]
+	trace add variable worddiff write changeworddiff
+	pack .bleft.mid.worddiff -side left -padx 5
+    }
+
     set ctext .bleft.bottom.ctext
     text $ctext -background $bgcolor -foreground $fgcolor \
 	-state disabled -font textfont \
@@ -7494,11 +7518,16 @@ proc changeignorespace {} {
     reselectline
 }
 
+proc changeworddiff {name ix op} {
+    reselectline
+}
+
 proc getblobdiffs {ids} {
     global blobdifffd diffids env
     global diffinhdr treediffs
     global diffcontext
     global ignorespace
+    global worddiff
     global limitdiffs vfilelimit curview
     global diffencoding targetline diffnparents
     global git_version
@@ -7515,6 +7544,9 @@ proc getblobdiffs {ids} {
     if {$ignorespace} {
 	append cmd " -w"
     }
+    if {$worddiff ne [mc "Line diff"]} {
+	append cmd " --word-diff=porcelain"
+    }
     if {$limitdiffs && $vfilelimit($curview) ne {}} {
 	set cmd [concat $cmd -- $vfilelimit($curview)]
     }
@@ -7599,6 +7631,7 @@ proc getblobdiffline {bdf ids} {
     global ctext_file_names ctext_file_lines
     global diffinhdr treediffs mergemax diffnparents
     global diffencoding jump_to_here targetline diffline
+    global worddiff
 
     set nr 0
     $ctext conf -state normal
@@ -7731,15 +7764,28 @@ proc getblobdiffline {bdf ids} {
 	    # parse the prefix - one ' ', '-' or '+' for each parent
 	    set prefix [string range $line 0 [expr {$diffnparents - 1}]]
 	    set tag [expr {$diffnparents > 1? "m": "d"}]
+	    set dowords [expr {$worddiff ne [mc "Line diff"] && $diffnparents == 1}]
+	    set words_pre_markup ""
+	    set words_post_markup ""
 	    if {[string trim $prefix " -+"] eq {}} {
 		# prefix only has " ", "-" and "+" in it: normal diff line
 		set num [string first "-" $prefix]
+		if {$dowords} {
+		    set line [string range $line 1 end]
+		}
 		if {$num >= 0} {
 		    # removed line, first parent with line is $num
 		    if {$num >= $mergemax} {
 			set num "max"
 		    }
-		    $ctext insert end "$line\n" $tag$num
+		    if {$dowords && $worddiff eq [mc "Markup words"]} {
+			$ctext insert end "\[-$line-\]" $tag$num
+		    } else {
+			$ctext insert end "$line" $tag$num
+		    }
+		    if {!$dowords} {
+			$ctext insert end "\n" $tag$num
+		    }
 		} else {
 		    set tags {}
 		    if {[string first "+" $prefix] >= 0} {
@@ -7754,6 +7800,8 @@ proc getblobdiffline {bdf ids} {
 				lappend tags m$num
 			    }
 			}
+			set words_pre_markup "{+"
+			set words_post_markup "+}"
 		    }
 		    if {$targetline ne {}} {
 			if {$diffline == $targetline} {
@@ -7763,8 +7811,17 @@ proc getblobdiffline {bdf ids} {
 			    incr diffline
 			}
 		    }
-		    $ctext insert end "$line\n" $tags
+		    if {$dowords && $worddiff eq [mc "Markup words"]} {
+			$ctext insert end "$words_pre_markup$line$words_post_markup" $tags
+		    } else {
+			$ctext insert end "$line" $tags
+		    }
+		    if {!$dowords} {
+			$ctext insert end "\n" $tags
+		    }
 		}
+	    } elseif {$dowords && $prefix eq "~"} {
+		$ctext insert end "\n" {}
 	    } else {
 		# "\ No newline at end of file",
 		# or something else we don't recognize
@@ -11383,6 +11440,7 @@ if {[tk windowingsystem] eq "win32"} {
 set diffcolors {red "#00a000" blue}
 set diffcontext 3
 set ignorespace 0
+set worddiff ""
 set markbgcolor "#e0e0ff"
 
 set circlecolors {white blue gray blue blue}
-- 
1.7.1.rc1.260.g41ab89

```

## Junio C Hamano, 2010-04-14 21:23

Subject: Re: [PATCH v4 1/3] diff: add --word-diff option that generalizes --color-words
Message-ID: <7vpr21ohj8.fsf@alter.siamese.dyndns.org>
URL: https://gitlist.dev/e/7vpr21ohj8.fsf%40alter.siamese.dyndns.org
In-Reply-To: <9a2b460ea5db47154623386638e883f749c4ee35.1271260308.git.trast@student.ethz.ch>

```
Looks good; I'll queue this one and hopefully Paul can give feedback to
the gitk patches.

Thanks.

```

## Jens Lehmann, 2010-04-15 19:57

Subject: Re: [PATCH v4 2/3] gitk: do not parse " >" context as submodule change
Message-ID: <4BC76FA2.3030204@web.de>
URL: https://gitlist.dev/e/4BC76FA2.3030204%40web.de
In-Reply-To: <5531510bfb94997f729a894a0b5a3158177a9add.1271260308.git.trast@student.ethz.ch>

```
Am 14.04.2010 17:59, schrieb Thomas Rast:
> Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
> when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
> at the beginning of a line in the submodule code even if we're in the
> diff text section and the lines should be treated as context.
> 
> Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
> case, and move the "  >"/"  <" specific code inside the $diffinhdr
> test.  The existing code will set $diffinhdr to 0 when it hits a
> "+++", so that it is always 0 when we can hit a context line.

Thanks for fixing this issue I accidentally introduced!

In that said patch I unfortunately also managed to screw up the
submodule name detection when it was not followed just by commits
(but e.g. by "contains untracked content"). I did already send a
patch to address this issue, but here is a rebased version on top
of your patch series just in case:

--------------------8<--------------------
From: Jens Lehmann <Jens.Lehmann@web.de>
Date: Thu, 15 Apr 2010 21:53:12 +0200
Subject: [PATCH] Teach gitk to display dirty submodules correctly

Since 1.7.1 "git diff --submodule" prints out extra lines when the
submodule contains untracked or modified files. Show all those lines for
one submodule under the same header.

Also e.g. for newly added or removed submodules the submodule name
contained trailing garbage because the extraction of the name was not
done right. Now it scans either for the first hex number followed by a
".." or the string "contains ".

Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
---
 gitk-git/gitk |   27 +++++++++++++++++++--------
 1 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/gitk-git/gitk b/gitk-git/gitk
index f2a1eb7..93d25ec 100644
--- a/gitk-git/gitk
+++ b/gitk-git/gitk
@@ -7530,7 +7530,7 @@ proc getblobdiffs {ids} {
     global worddiff
     global limitdiffs vfilelimit curview
     global diffencoding targetline diffnparents
-    global git_version
+    global git_version currdiffsubmod

     set textconv {}
     if {[package vcompare $git_version "1.6.1"] >= 0} {
@@ -7560,6 +7560,7 @@ proc getblobdiffs {ids} {
     set diffencoding [get_path_encoding {}]
     fconfigure $bdf -blocking 0 -encoding binary -eofchar {}
     set blobdifffd($ids) $bdf
+    set currdiffsubmod ""
     filerun $bdf [list getblobdiffline $bdf $diffids]
 }

@@ -7631,7 +7632,7 @@ proc getblobdiffline {bdf ids} {
     global ctext_file_names ctext_file_lines
     global diffinhdr treediffs mergemax diffnparents
     global diffencoding jump_to_here targetline diffline
-    global worddiff
+    global worddiff currdiffsubmod

     set nr 0
     $ctext conf -state normal
@@ -7712,15 +7713,24 @@ proc getblobdiffline {bdf ids} {

 	} elseif {![string compare -length 10 "Submodule " $line]} {
 	    # start of a new submodule
-	    if {[string compare [$ctext get "end - 4c" end] "\n \n\n"]} {
+	    if {[regexp -indices "\[0-9a-f\]+\\.\\." $line nameend]} {
+		set fname [string range $line 10 [expr [lindex $nameend 0] - 2]]
+	    } else {
+		set fname [string range $line 10 [expr [string first "contains " $line] - 2]]
+	    }
+	    if {$currdiffsubmod != $fname} {
 		$ctext insert end "\n";     # Add newline after commit message
 	    }
 	    set curdiffstart [$ctext index "end - 1c"]
 	    lappend ctext_file_names ""
-	    set fname [string range $line 10 [expr [string last " " $line] - 1]]
-	    lappend ctext_file_lines $fname
-	    makediffhdr $fname $ids
-	    $ctext insert end "\n$line\n" filesep
+	    if {$currdiffsubmod != $fname} {
+		lappend ctext_file_lines $fname
+		makediffhdr $fname $ids
+		set currdiffsubmod $fname
+		$ctext insert end "\n$line\n" filesep
+	    } else {
+		$ctext insert end "$line\n" filesep
+	    }
 	    # pretend we're in a file header to correctly parse "  [><]"
 	    set diffinhdr 1
 	} elseif {$diffinhdr} {
@@ -8588,7 +8598,7 @@ proc do_cmp_commits {a b} {
 }

 proc diffcommits {a b} {
-    global diffcontext diffids blobdifffd diffinhdr
+    global diffcontext diffids blobdifffd diffinhdr currdiffsubmod

     set tmpdir [gitknewtmpdir]
     set fna [file join $tmpdir "commit-[string range $a 0 7]"]
@@ -8609,6 +8619,7 @@ proc diffcommits {a b} {
     set diffids [list commits $a $b]
     set blobdifffd($diffids) $fd
     set diffinhdr 0
+    set currdiffsubmod ""
     filerun $fd [list getblobdiffline $fd $diffids]
 }

-- 
1.7.1.rc1.252.gff9f

```

## Paul Mackerras, 2010-04-17 06:33

Subject: Re: [PATCH v4 2/3] gitk: do not parse " >" context as submodule change
Message-ID: <20100417063320.GA6681@brick.ozlabs.ibm.com>
URL: https://gitlist.dev/e/20100417063320.GA6681%40brick.ozlabs.ibm.com
In-Reply-To: <5531510bfb94997f729a894a0b5a3158177a9add.1271260308.git.trast@student.ethz.ch>

```
On Wed, Apr 14, 2010 at 05:59:07PM +0200, Thomas Rast wrote:

> Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
> when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
> at the beginning of a line in the submodule code even if we're in the
> diff text section and the lines should be treated as context.
> 
> Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
> case, and move the "  >"/"  <" specific code inside the $diffinhdr
> test.  The existing code will set $diffinhdr to 0 when it hits a
> "+++", so that it is always 0 when we can hit a context line.

Looks good, but there's no Signed-off-by?

Paul.

```

## Paul Mackerras, 2010-04-17 06:35

Subject: Re: [PATCH v4 3/3] gitk: add the equivalent of diff --color-words
Message-ID: <20100417063557.GB6681@brick.ozlabs.ibm.com>
URL: https://gitlist.dev/e/20100417063557.GB6681%40brick.ozlabs.ibm.com
In-Reply-To: <bc720738f918f0523842b3839b7e611c453b5241.1271260308.git.trast@student.ethz.ch>

```
On Wed, Apr 14, 2010 at 05:59:08PM +0200, Thomas Rast wrote:

> Use the newly added 'diff --word-diff=porcelain' to teach gitk a
> color-words mode, with two different modes analogous to the
> --word-diff=plain and --word-diff=color settings.  These are selected
> by a dropdown box.
> 
> As an extra twist, automatically enable this word-diff support when
> the user mentions a word-diff related option on the command line.
> These options were previously ignored because they would break diff
> parsing.
> 
> Both of these features are only enabled if we have a version of git
> that supports --word-diff=porcelain, tentatively set to 1.7.2.
> 
> Signed-off-by: Thomas Rast <trast@student.ethz.ch>

Looks fine.  The only nit I can see is that a "--word-diffoobar"
option would get treated as "--word-diff=plain" rather than giving an
error or being passed as-is to git log.

When does this need to go in, i.e. when is the git patch likely to go
in?

Paul.

```

## Junio C Hamano, 2010-04-17 06:55

Subject: Re: [PATCH v4 3/3] gitk: add the equivalent of diff --color-words
Message-ID: <7vhbna601d.fsf@alter.siamese.dyndns.org>
URL: https://gitlist.dev/e/7vhbna601d.fsf%40alter.siamese.dyndns.org
In-Reply-To: <20100417063557.GB6681@brick.ozlabs.ibm.com>

```
Paul Mackerras <paulus@samba.org> writes:

> When does this need to go in, i.e. when is the git patch likely to go
> in?

I am expecting that this will be in soon after the current 1.7.1 cycle,
sometime around early-to-mid May timeframe.

```

## Thomas Rast, 2010-04-17 12:20

Subject: Re: [PATCH v4 2/3] gitk: do not parse " >" context as submodule change
Message-ID: <201004171420.55737.trast@student.ethz.ch>
URL: https://gitlist.dev/e/201004171420.55737.trast%40student.ethz.ch
In-Reply-To: <20100417063320.GA6681@brick.ozlabs.ibm.com>

```
Paul Mackerras wrote:
> On Wed, Apr 14, 2010 at 05:59:07PM +0200, Thomas Rast wrote:
> 
> > Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
> > when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
> > at the beginning of a line in the submodule code even if we're in the
> > diff text section and the lines should be treated as context.
> > 
> > Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
> > case, and move the "  >"/"  <" specific code inside the $diffinhdr
> > test.  The existing code will set $diffinhdr to 0 when it hits a
> > "+++", so that it is always 0 when we can hit a context line.
> 
> Looks good, but there's no Signed-off-by?

Whoops, sorry:

Signed-off-by: Thomas Rast <trast@student.ethz.ch>

-- 
Thomas Rast
trast@{inf,student}.ethz.ch

```

## Paul Mackerras, 2010-04-19 01:08

Subject: Re: [PATCH v4 2/3] gitk: do not parse " >" context as submodule change
Message-ID: <20100419010819.GA4386@brick.ozlabs.ibm.com>
URL: https://gitlist.dev/e/20100419010819.GA4386%40brick.ozlabs.ibm.com
In-Reply-To: <201004171420.55737.trast@student.ethz.ch>

```
On Sat, Apr 17, 2010 at 02:20:55PM +0200, Thomas Rast wrote:

> Whoops, sorry:
> 
> Signed-off-by: Thomas Rast <trast@student.ethz.ch>

Thanks, but now that I have applied Jens Lehmann's patch that also
touches this area, your patch doesn't apply.  Could you rebase it and
send it again?

Thanks,
Paul.

```