git/ws.c
J. Bruce Fields ffe568859b whitespace: more accurate initial-indent highlighting
Instead of highlighting the entire initial indent, highlight only the
problematic spaces.

In the case of an indent like ' \t \t' there may be multiple problematic
ranges, so it's easiest to emit the highlighting as we go instead of
trying rember disjoint ranges and do it all at the end.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-12-16 13:07:58 -08:00

204 lines
4.7 KiB
C

/*
* Whitespace rules
*
* Copyright (c) 2007 Junio C Hamano
*/
#include "cache.h"
#include "attr.h"
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 },
};
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;
}
static void setup_whitespace_attr_check(struct git_attr_check *check)
{
static struct git_attr *attr_whitespace;
if (!attr_whitespace)
attr_whitespace = git_attr("whitespace", 10);
check[0].attr = attr_whitespace;
}
unsigned whitespace_rule(const char *pathname)
{
struct git_attr_check attr_whitespace_rule;
setup_whitespace_attr_check(&attr_whitespace_rule);
if (!git_checkattr(pathname, 1, &attr_whitespace_rule)) {
const char *value;
value = attr_whitespace_rule.value;
if (ATTR_TRUE(value)) {
/* true (whitespace) */
unsigned all_rule = 0;
int i;
for (i = 0; i < ARRAY_SIZE(whitespace_rule_names); i++)
all_rule |= whitespace_rule_names[i].rule_bits;
return all_rule;
} else if (ATTR_FALSE(value)) {
/* false (-whitespace) */
return 0;
} else if (ATTR_UNSET(value)) {
/* reset to default (!whitespace) */
return whitespace_rule_cfg;
} else {
/* string */
return parse_whitespace_rule(value);
}
} else {
return whitespace_rule_cfg;
}
}
/* The returned string should be freed by the caller. */
char *whitespace_error_string(unsigned ws)
{
struct strbuf err;
strbuf_init(&err, 0);
if (ws & WS_TRAILING_SPACE)
strbuf_addstr(&err, "trailing whitespace");
if (ws & WS_SPACE_BEFORE_TAB) {
if (err.len)
strbuf_addstr(&err, ", ");
strbuf_addstr(&err, "space before tab in indent");
}
if (ws & WS_INDENT_WITH_NON_TAB) {
if (err.len)
strbuf_addstr(&err, ", ");
strbuf_addstr(&err, "indent with spaces");
}
return strbuf_detach(&err, NULL);
}
/* If stream is non-NULL, emits the line after checking. */
unsigned check_and_emit_line(const char *line, int len, unsigned ws_rule,
FILE *stream, const char *set,
const char *reset, const char *ws)
{
unsigned result = 0;
int written = 0;
int trailing_whitespace = -1;
int trailing_newline = 0;
int i;
/* Logic is simpler if we temporarily ignore the trailing newline. */
if (len > 0 && line[len - 1] == '\n') {
trailing_newline = 1;
len--;
}
/* Check for trailing whitespace. */
if (ws_rule & WS_TRAILING_SPACE) {
for (i = len - 1; i >= 0; i--) {
if (isspace(line[i])) {
trailing_whitespace = i;
result |= WS_TRAILING_SPACE;
}
else
break;
}
}
/* Check for space before tab in initial indent. */
for (i = 0; i < len; i++) {
if (line[i] == ' ')
continue;
if (line[i] != '\t')
break;
if ((ws_rule & WS_SPACE_BEFORE_TAB) && written < i) {
result |= WS_SPACE_BEFORE_TAB;
if (stream) {
fputs(ws, stream);
fwrite(line + written, i - written, 1, stream);
fputs(reset, stream);
}
} else if (stream)
fwrite(line + written, i - written, 1, stream);
if (stream)
fwrite(line + i, 1, 1, stream);
written = i + 1;
}
/* Check for indent using non-tab. */
if ((ws_rule & WS_INDENT_WITH_NON_TAB) && i - written >= 8) {
result |= WS_INDENT_WITH_NON_TAB;
if (stream) {
fputs(ws, stream);
fwrite(line + written, i - written, 1, stream);
fputs(reset, stream);
}
written = i;
}
if (stream) {
/* Now the rest of the line starts at written.
* The non-highlighted part ends at trailing_whitespace. */
if (trailing_whitespace == -1)
trailing_whitespace = len;
/* Emit non-highlighted (middle) segment. */
if (trailing_whitespace - written > 0) {
fputs(set, stream);
fwrite(line + written,
trailing_whitespace - written, 1, stream);
fputs(reset, stream);
}
/* Highlight errors in trailing whitespace. */
if (trailing_whitespace != len) {
fputs(ws, stream);
fwrite(line + trailing_whitespace,
len - trailing_whitespace, 1, stream);
fputs(reset, stream);
}
if (trailing_newline)
fputc('\n', stream);
}
return result;
}