git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCH 1/2] War on whitespace: first, a bit of retreat.

From
Junio C Hamano <gitster@pobox.com>
Date
Nov 2, 2007, 07:34 UTC
Message-ID
<7vwst15ceq.fsf@gitster.siamese.dyndns.org>

This introduces core.whitespace configuration variable that lets you specify the definition of "whitespace error".

Currently there are two kinds of whitespace errors defined:
 * trailing-space: trailing whitespaces at the end of the line.
 * space-before-tab: a SP appears immediately before HT in the
   indent part of the line.

You can specify the desired types of errors to be detected by listing their names (unique abbreviations are accepted) separated by comma. By default, these two errors are always detected, as that is the traditional behaviour. You can disable detection of a particular type of error by prefixing a '-' in front of the name of the error, like this:

	[core]
		whitespace = -trailing-space

This patch teaches the code to output colored diff with DIFF_WHITESPACE color to highlight the detected whitespace errors to honor the new configuration.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 cache.h       |    9 +++++++++
 config.c      |   52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 diff.c        |   13 ++++++++-----
 environment.c |    1 +
 4 files changed, 70 insertions(+), 5 deletions(-)
diff --git a/cache.h b/cache.h
index bfffa05..a6e5988 100644
--- a/cache.h
+++ b/cache.h
@@ -602,4 +602,13 @@ extern int diff_auto_refresh_index;
 /* match-trees.c */
 void shift_tree(const unsigned char *, const unsigned char *, unsigned char *, int);
 
+/*
+ * whitespace rules.
+ * used by both diff and apply
+ */
+#define WS_TRAILING_SPACE	01
+#define WS_SPACE_BEFORE_TAB	02
+#define WS_DEFAULT_RULE (WS_TRAILING_SPACE|WS_SPACE_BEFORE_TAB)
+extern unsigned whitespace_rule;
+
 #endif /* CACHE_H */
diff --git a/config.c b/config.c
index dc3148d..ffb418c 100644
--- a/config.c
+++ b/config.c
@@ -246,6 +246,53 @@ 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 },
+};
+
+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) {
@@ -431,6 +478,11 @@ int git_default_config(const char *var, const char *value)
 		return 0;
 	}
 
+	if (!strcmp(var, "core.whitespace")) {
+		whitespace_rule = parse_whitespace_rule(value);
+		return 0;
+	}
+
 	/* Add other config variables here and to Documentation/config.txt. */
 	return 0;
 }
diff --git a/diff.c b/diff.c
index a6aaaf7..2112353 100644
--- a/diff.c
+++ b/diff.c
@@ -508,7 +508,8 @@ static void emit_line_with_ws(int nparents,
 	for (i = col0; i < len; i++) {
 		if (line[i] == '\t') {
 			last_tab_in_indent = i;
-			if (0 <= last_space_in_indent)
+			if ((whitespace_rule & WS_SPACE_BEFORE_TAB) &&
+			    0 <= last_space_in_indent)
 				need_highlight_leading_space = 1;
 		}
 		else if (line[i] == ' ')
@@ -540,10 +541,12 @@ static void emit_line_with_ws(int nparents,
 	tail = len - 1;
 	if (line[tail] == '\n' && i < tail)
 		tail--;
-	while (i < tail) {
-		if (!isspace(line[tail]))
-			break;
-		tail--;
+	if (whitespace_rule & WS_TRAILING_SPACE) {
+		while (i < tail) {
+			if (!isspace(line[tail]))
+				break;
+			tail--;
+		}
 	}
 	if ((i < tail && line[tail + 1] != '\n')) {
 		/* This has whitespace between tail+1..len */
diff --git a/environment.c b/environment.c
index b5a6c69..624dd96 100644
--- a/environment.c
+++ b/environment.c
@@ -35,6 +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;
 
 /* This is set by setup_git_dir_gently() and/or git_default_config() */
 char *git_work_tree_cfg;
-- 
1.5.3.5.1452.ga93d
Next: Junio C Hamano
Message 1 of 12 in “War on whitespace: first, a bit of retreat.”
  1. 1/2 War on whitespace: first, a bit of retreat.Junio C Hamano, Nov 2, 2007
  2. 2/2 git-diff: complain about >=8 consecutive spaces in initial indentJunio C Hamano, Nov 2, 2007
  3. Josh TriplettNov 13, 2007
  4. Junio C HamanoNov 14, 2007
  5. David SymondsNov 2, 2007
  6. Andreas EricssonNov 2, 2007
  7. David SymondsNov 2, 2007
  8. Jakub NarebskiNov 2, 2007
  9. David SymondsNov 2, 2007
  10. David SymondsNov 2, 2007
  11. J. Bruce FieldsNov 2, 2007
  12. Junio C HamanoNov 3, 2007

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.