Use gitattributes to define per-path whitespace rule

gitster · gitster · commit cf1b7869f0c5 · 2007-12-06T00:45:30.000-08:00
The `core.whitespace` configuration variable allows you to define what
`diff` and `apply` should consider whitespace errors for all paths in
the project (See gitlink:git-config[1]).  This attribute gives you finer
control per path.

For example, if you have these in the .gitattributes:

    frotz   whitespace
    nitfol  -whitespace
    xyzzy   whitespace=-trailing

all types of whitespace problems known to git are noticed in path 'frotz'
(i.e. diff shows them in diff.whitespace color, and apply warns about
them), no whitespace problem is noticed in path 'nitfol', and the
default types of whitespace problems except "trailing whitespace" are
noticed for path 'xyzzy'.  A project with mixed Python and C might want
to have:

    *.c    whitespace
    *.py   whitespace=-indent-with-non-tab

in its toplevel .gitattributes file.

Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
@@ -360,6 +360,37 @@ When left unspecified, the driver itself is used for both
 internal merge and the final merge.
 
 
+Checking whitespace errors
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+`whitespace`
+^^^^^^^^^^^^
+
+The `core.whitespace` configuration variable allows you to define what
+`diff` and `apply` should consider whitespace errors for all paths in
+the project (See gitlink:git-config[1]).  This attribute gives you finer
+control per path.
+
+Set::
+
+	Notice all types of potential whitespace errors known to git.
+
+Unset::
+
+	Do not notice anything as error.
+
+Unspecified::
+
+	Use the value of `core.whitespace` configuration variable to
+	decide what to notice as error.
+
+String::
+
+	Specify a comma separate list of common whitespace problems to
+	notice in the same format as `core.whitespace` configuration
+	variable.
+
+
 EXAMPLE
 -------
 
diff --git a/Makefile b/Makefile
@@ -312,7 +312,7 @@ LIB_OBJS = \
 	alloc.o merge-file.o path-list.o help.o unpack-trees.o $(DIFF_OBJS) \
 	color.o wt-status.o archive-zip.o archive-tar.o shallow.o utf8.o \
 	convert.o attr.o decorate.o progress.o mailmap.o symlinks.o remote.o \
-	transport.o bundle.o walker.o parse-options.o
+	transport.o bundle.o walker.o parse-options.o ws.o
 
 BUILTIN_OBJS = \
 	builtin-add.o \
diff --git a/builtin-apply.c b/builtin-apply.c
@@ -144,6 +144,7 @@ struct patch {
 	unsigned int old_mode, new_mode;
 	int is_new, is_delete;	/* -1 = unknown, 0 = false, 1 = true */
 	int rejected;
+	unsigned ws_rule;
 	unsigned long deflate_origlen;
 	int lines_added, lines_deleted;
 	int score;
@@ -898,7 +899,7 @@ static int find_header(char *line, unsigned long size, int *hdrsize, struct patc
 	return -1;
 }
 
-static void check_whitespace(const char *line, int len)
+static void check_whitespace(const char *line, int len, unsigned ws_rule)
 {
 	const char *err = "Adds trailing whitespace";
 	int seen_space = 0;
@@ -910,14 +911,14 @@ static void check_whitespace(const char *line, int len)
 	 * this function.  That is, an addition of an empty line would
 	 * check the '+' here.  Sneaky...
 	 */
-	if ((whitespace_rule & WS_TRAILING_SPACE) && isspace(line[len-2]))
+	if ((ws_rule & WS_TRAILING_SPACE) && isspace(line[len-2]))
 		goto error;
 
 	/*
 	 * Make sure that there is no space followed by a tab in
 	 * indentation.
 	 */
-	if (whitespace_rule & WS_SPACE_BEFORE_TAB) {
+	if (ws_rule & WS_SPACE_BEFORE_TAB) {
 		err = "Space in indent is followed by a tab";
 		for (i = 1; i < len; i++) {
 			if (line[i] == '\t') {
@@ -935,7 +936,7 @@ static void check_whitespace(const char *line, int len)
 	 * Make sure that the indentation does not contain more than
 	 * 8 spaces.
 	 */
-	if ((whitespace_rule & WS_INDENT_WITH_NON_TAB) &&
+	if ((ws_rule & WS_INDENT_WITH_NON_TAB) &&
 	    (8 < len) && !strncmp("+        ", line, 9)) {
 		err = "Indent more than 8 places with spaces";
 		goto error;
@@ -1001,15 +1002,15 @@ static int parse_fragment(char *line, unsigned long size,
 		case '-':
 			if (apply_in_reverse &&
 			    ws_error_action != nowarn_ws_error)
-				check_whitespace(line, len);
+				check_whitespace(line, len, patch->ws_rule);
 			deleted++;
 			oldlines--;
 			trailing = 0;
 			break;
 		case '+':
 			if (!apply_in_reverse &&
 			    ws_error_action != nowarn_ws_error)
-				check_whitespace(line, len);
+				check_whitespace(line, len, patch->ws_rule);
 			added++;
 			newlines--;
 			trailing = 0;
@@ -1318,6 +1319,10 @@ static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
 	if (offset < 0)
 		return offset;
 
+	patch->ws_rule = whitespace_rule(patch->new_name
+					 ? patch->new_name
+					 : patch->old_name);
+
 	patchsize = parse_single_patch(buffer + offset + hdrsize,
 				       size - offset - hdrsize, patch);
 
@@ -1568,7 +1573,8 @@ static void remove_last_line(const char **rbuf, int *rsize)
 	*rsize = offset + 1;
 }
 
-static int apply_line(char *output, const char *patch, int plen)
+static int apply_line(char *output, const char *patch, int plen,
+		      unsigned ws_rule)
 {
 	/*
 	 * plen is number of bytes to be copied from patch,
@@ -1593,7 +1599,7 @@ static int apply_line(char *output, const char *patch, int plen)
 	/*
 	 * Strip trailing whitespace
 	 */
-	if ((whitespace_rule & WS_TRAILING_SPACE) &&
+	if ((ws_rule & WS_TRAILING_SPACE) &&
 	    (1 < plen && isspace(patch[plen-1]))) {
 		if (patch[plen] == '\n')
 			add_nl_to_tail = 1;
@@ -1610,12 +1616,12 @@ static int apply_line(char *output, const char *patch, int plen)
 		char ch = patch[i];
 		if (ch == '\t') {
 			last_tab_in_indent = i;
-			if ((whitespace_rule & WS_SPACE_BEFORE_TAB) &&
+			if ((ws_rule & WS_SPACE_BEFORE_TAB) &&
 			    0 <= last_space_in_indent)
 			    need_fix_leading_space = 1;
 		} else if (ch == ' ') {
 			last_space_in_indent = i;
-			if ((whitespace_rule & WS_INDENT_WITH_NON_TAB) &&
+			if ((ws_rule & WS_INDENT_WITH_NON_TAB) &&
 			    last_tab_in_indent < 0 &&
 			    8 <= i)
 				need_fix_leading_space = 1;
@@ -1629,7 +1635,7 @@ static int apply_line(char *output, const char *patch, int plen)
 		int consecutive_spaces = 0;
 		int last = last_tab_in_indent + 1;
 
-		if (whitespace_rule & WS_INDENT_WITH_NON_TAB) {
+		if (ws_rule & WS_INDENT_WITH_NON_TAB) {
 			/* have "last" point at one past the indent */
 			if (last_tab_in_indent < last_space_in_indent)
 				last = last_space_in_indent + 1;
@@ -1671,7 +1677,7 @@ static int apply_line(char *output, const char *patch, int plen)
 }
 
 static int apply_one_fragment(struct strbuf *buf, struct fragment *frag,
-			      int inaccurate_eof)
+			      int inaccurate_eof, unsigned ws_rule)
 {
 	int match_beginning, match_end;
 	const char *patch = frag->patch;
@@ -1730,7 +1736,7 @@ static int apply_one_fragment(struct strbuf *buf, struct fragment *frag,
 		case '+':
 			if (first != '+' || !no_add) {
 				int added = apply_line(new + newsize, patch,
-						       plen);
+						       plen, ws_rule);
 				newsize += added;
 				if (first == '+' &&
 				    added == 1 && new[newsize-1] == '\n')
@@ -1953,12 +1959,14 @@ static int apply_fragments(struct strbuf *buf, struct patch *patch)
 {
 	struct fragment *frag = patch->fragments;
 	const char *name = patch->old_name ? patch->old_name : patch->new_name;
+	unsigned ws_rule = patch->ws_rule;
+	unsigned inaccurate_eof = patch->inaccurate_eof;
 
 	if (patch->is_binary)
 		return apply_binary(buf, patch);
 
 	while (frag) {
-		if (apply_one_fragment(buf, frag, patch->inaccurate_eof)) {
+		if (apply_one_fragment(buf, frag, inaccurate_eof, ws_rule)) {
 			error("patch failed: %s:%ld", name, frag->oldpos);
 			if (!apply_with_reject)
 				return -1;
diff --git a/cache.h b/cache.h
@@ -610,6 +610,8 @@ void shift_tree(const unsigned char *, const unsigned char *, unsigned char *, i
 #define WS_SPACE_BEFORE_TAB	02
 #define WS_INDENT_WITH_NON_TAB	04
 #define WS_DEFAULT_RULE (WS_TRAILING_SPACE|WS_SPACE_BEFORE_TAB)
-extern unsigned whitespace_rule;
+extern unsigned whitespace_rule_cfg;
+extern unsigned whitespace_rule(const char *);
+extern unsigned parse_whitespace_rule(const char *);
 
 #endif /* CACHE_H */
diff --git a/config.c b/config.c
@@ -246,54 +246,6 @@ static unsigned long get_unit_factor(const char *end)
 	die("unknown unit: '%s'", end);
 }
 
-static struct whitespace_rule {
-	const char *rule_name;
-	unsigned rule_bits;
-} whitespace_rule_names[] = {
-	{ "trailing-space", WS_TRAILING_SPACE },
-	{ "space-before-tab", WS_SPACE_BEFORE_TAB },
-	{ "indent-with-non-tab", WS_INDENT_WITH_NON_TAB },
-};
-
-static unsigned parse_whitespace_rule(const char *string)
-{
-	unsigned rule = WS_DEFAULT_RULE;
-
-	while (string) {
-		int i;
-		size_t len;
-		const char *ep;
-		int negated = 0;
-
-		string = string + strspn(string, ", \t\n\r");
-		ep = strchr(string, ',');
-		if (!ep)
-			len = strlen(string);
-		else
-			len = ep - string;
-
-		if (*string == '-') {
-			negated = 1;
-			string++;
-			len--;
-		}
-		if (!len)
-			break;
-		for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++) {
-			if (strncmp(whitespace_rule_names[i].rule_name,
-				    string, len))
-				continue;
-			if (negated)
-				rule &= ~whitespace_rule_names[i].rule_bits;
-			else
-				rule |= whitespace_rule_names[i].rule_bits;
-			break;
-		}
-		string = ep;
-	}
-	return rule;
-}
-
 int git_parse_long(const char *value, long *ret)
 {
 	if (value && *value) {
@@ -480,7 +432,7 @@ int git_default_config(const char *var, const char *value)
 	}
 
 	if (!strcmp(var, "core.whitespace")) {
-		whitespace_rule = parse_whitespace_rule(value);
+		whitespace_rule_cfg = parse_whitespace_rule(value);
 		return 0;
 	}
 
diff --git a/diff.c b/diff.c
@@ -454,6 +454,7 @@ static void diff_words_show(struct diff_words_data *diff_words)
 struct emit_callback {
 	struct xdiff_emit_state xm;
 	int nparents, color_diff;
+	unsigned ws_rule;
 	const char **label_path;
 	struct diff_words_data *diff_words;
 	int *found_changesp;
@@ -493,8 +494,8 @@ static void emit_line(const char *set, const char *reset, const char *line, int
 }
 
 static void emit_line_with_ws(int nparents,
-		const char *set, const char *reset, const char *ws,
-		const char *line, int len)
+			      const char *set, const char *reset, const char *ws,
+			      const char *line, int len, unsigned ws_rule)
 {
 	int col0 = nparents;
 	int last_tab_in_indent = -1;
@@ -511,7 +512,7 @@ static void emit_line_with_ws(int nparents,
 	for (i = col0; i < len; i++) {
 		if (line[i] == '\t') {
 			last_tab_in_indent = i;
-			if ((whitespace_rule & WS_SPACE_BEFORE_TAB) &&
+			if ((ws_rule & WS_SPACE_BEFORE_TAB) &&
 			    0 <= last_space_in_indent)
 				need_highlight_leading_space = 1;
 		}
@@ -520,7 +521,7 @@ static void emit_line_with_ws(int nparents,
 		else
 			break;
 	}
-	if ((whitespace_rule & WS_INDENT_WITH_NON_TAB) &&
+	if ((ws_rule & WS_INDENT_WITH_NON_TAB) &&
 	    0 <= last_space_in_indent &&
 	    last_tab_in_indent < 0 &&
 	    8 <= (i - col0)) {
@@ -551,7 +552,7 @@ static void emit_line_with_ws(int nparents,
 	tail = len - 1;
 	if (line[tail] == '\n' && i < tail)
 		tail--;
-	if (whitespace_rule & WS_TRAILING_SPACE) {
+	if (ws_rule & WS_TRAILING_SPACE) {
 		while (i < tail) {
 			if (!isspace(line[tail]))
 				break;
@@ -578,7 +579,7 @@ static void emit_add_line(const char *reset, struct emit_callback *ecbdata, cons
 		emit_line(set, reset, line, len);
 	else
 		emit_line_with_ws(ecbdata->nparents, set, reset, ws,
-				line, len);
+				  line, len, ecbdata->ws_rule);
 }
 
 static void fn_out_consume(void *priv, char *line, unsigned long len)
@@ -994,6 +995,7 @@ struct checkdiff_t {
 	struct xdiff_emit_state xm;
 	const char *filename;
 	int lineno, color_diff;
+	unsigned ws_rule;
 };
 
 static void checkdiff_consume(void *priv, char *line, unsigned long len)
@@ -1029,7 +1031,8 @@ static void checkdiff_consume(void *priv, char *line, unsigned long len)
 			if (white_space_at_end)
 				printf("white space at end");
 			printf(":%s ", reset);
-			emit_line_with_ws(1, set, reset, ws, line, len);
+			emit_line_with_ws(1, set, reset, ws, line, len,
+					  data->ws_rule);
 		}
 
 		data->lineno++;
@@ -1330,6 +1333,7 @@ static void builtin_diff(const char *name_a,
 		ecbdata.label_path = lbl;
 		ecbdata.color_diff = o->color_diff;
 		ecbdata.found_changesp = &o->found_changes;
+		ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
 		xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
 		xecfg.ctxlen = o->context;
 		xecfg.flags = XDL_EMIT_FUNCNAMES;
@@ -1423,6 +1427,7 @@ static void builtin_checkdiff(const char *name_a, const char *name_b,
 	data.filename = name_b ? name_b : name_a;
 	data.lineno = 0;
 	data.color_diff = o->color_diff;
+	data.ws_rule = whitespace_rule(data.filename);
 
 	if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 		die("unable to read files to diff");
diff --git a/environment.c b/environment.c
@@ -35,7 +35,7 @@ int pager_in_use;
 int pager_use_color = 1;
 char *editor_program;
 int auto_crlf = 0;	/* 1: both ways, -1: only when adding git objects */
-unsigned whitespace_rule = WS_DEFAULT_RULE;
+unsigned whitespace_rule_cfg = WS_DEFAULT_RULE;
 
 /* This is set by setup_git_dir_gently() and/or git_default_config() */
 char *git_work_tree_cfg;
diff --git a/t/t4019-diff-wserror.sh b/t/t4019-diff-wserror.sh
diff --git a/t/t4124-apply-ws-rule.sh b/t/t4124-apply-ws-rule.sh
diff --git a/ws.c b/ws.c
