[PATCH v2 2/2] dir.c: don't exclude whole dir prematurely if neg pattern may match
If there is a pattern "!foo/bar", this patch makes it not exclude "foo" right away. This gives us a chance to examine "foo" and re-include "foo/bar".
In order for it to detect that the directory under examination should not be excluded right away, in other words it is a parent directory of a negative pattern, the "directory path" of the negative pattern must be literal. Patterns like "!f?o/bar" can't stop "foo" from being excluded.
Basename matching (i.e. "no slashes in the pattern") or must-be-dir matching (i.e. "trailing slash in the pattern") does not work well with this. For example, if we descend in "foo" and are examining "foo/abc", current code for "foo/" pattern will check if path "foo/abc", not "foo", is a directory. The same problem with basename matching. These may need big code reorg to make it work.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
Documentation/gitignore.txt | 21 ++++++++---
dir.c | 76 +++++++++++++++++++++++++++++++++++++-
t/t3001-ls-files-others-exclude.sh | 20 ++++++++++
3 files changed, 109 insertions(+), 8 deletions(-)
Show changes to 3 files +109 −8
Documentation/gitignore.txt, dir.c, t/t3001-ls-files-others-exclude.sh
diff --git a/Documentation/gitignore.txt b/Documentation/gitignore.txt
index 473623d..889a72a 100644
--- a/Documentation/gitignore.txt
+++ b/Documentation/gitignore.txt
@@ -82,12 +82,9 @@ PATTERN FORMAT
- An optional prefix "`!`" which negates the pattern; any
matching file excluded by a previous pattern will become
- included again. It is not possible to re-include a file if a parent
- directory of that file is excluded. Git doesn't list excluded
- directories for performance reasons, so any patterns on contained
- files have no effect, no matter where they are defined.
- Put a backslash ("`\`") in front of the first "`!`" for patterns
- that begin with a literal "`!`", for example, "`\!important!.txt`".
+ included again. It is possible to re-include a file if a parent
+ directory of that file is excluded, with restrictions. See section
+ NOTES for detail.
- If the pattern ends with a slash, it is removed for the
purpose of the following description, but it would only find
@@ -141,6 +138,18 @@ not tracked by Git remain untracked.
To stop tracking a file that is currently tracked, use
'git rm --cached'.
+To re-include a file when its parent directory is excluded, the
+following conditions must be met:
+
+ - The directory part in the re-include rules must be literal (i.e. no
+ wildcards)
+
+ - The rules to exclude the parent directory must not end with a
+ trailing slash.
+
+ - The rules to exclude the parent directory must have at least one
+ slash.
+
EXAMPLES
--------
diff --git a/dir.c b/dir.c
index 3a7630a..a1f711c 100644
--- a/dir.c
+++ b/dir.c
@@ -882,6 +882,25 @@ int match_pathname(const char *pathname, int pathlen,
*/
if (!patternlen && !namelen)
return 1;
+ /*
+ * This can happen when we ignore some exclude rules
+ * on directories in other to see if negative rules
+ * may match. E.g.
+ *
+ * /abc
+ * !/abc/def/ghi
+ *
+ * The pattern of interest is "/abc". On the first
+ * try, we should match path "abc" with this pattern
+ * in the "if" statement right above, but the caller
+ * ignores it.
+ *
+ * On the second try with paths within "abc",
+ * e.g. "abc/xyz", we come here and try to match it
+ * with "/abc".
+ */
+ if (!patternlen && namelen && *name == '/')
+ return 1;
}
return fnmatch_icase_mem(pattern, patternlen,
@@ -890,6 +909,48 @@ int match_pathname(const char *pathname, int pathlen,
}
/*
+ * Return non-zero if pathname is a directory and an ancestor of the
+ * literal path in a (negative) pattern. This is used to keep
+ * descending in "foo" and "foo/bar" when the pattern is
+ * "!foo/bar/.gitignore". "foo/notbar" will not be descended however.
+ */
+static int match_neg_path(const char *pathname, int pathlen, int *dtype,
+ const char *base, int baselen,
+ const char *pattern, int prefix, int patternlen,
+ int flags)
+{
+ assert((flags & EXC_FLAG_NEGATIVE) && !(flags & EXC_FLAG_NODIR));
+
+ if (*dtype == DT_UNKNOWN)
+ *dtype = get_dtype(NULL, pathname, pathlen);
+ if (*dtype != DT_DIR)
+ return 0;
+
+ if (*pattern == '/') {
+ pattern++;
+ patternlen--;
+ prefix--;
+ }
+
+ if (baselen) {
+ if (((pathlen < baselen && base[pathlen] == '/') ||
+ pathlen == baselen) &&
+ !strncmp_icase(pathname, base, pathlen))
+ return 1;
+ pathname += baselen + 1;
+ pathlen -= baselen + 1;
+ }
+
+
+ if (prefix &&
+ ((pathlen < prefix && pattern[pathlen] == '/') &&
+ !strncmp_icase(pathname, pattern, pathlen)))
+ return 1;
+
+ return 0;
+}
+
+/*
* Scan the given exclude list in reverse to see whether pathname
* should be ignored. The first match (i.e. the last on the list), if
* any, determines the fate. Returns the exclude_list element which
@@ -902,7 +963,7 @@ static struct exclude *last_exclude_matching_from_list(const char *pathname,
struct exclude_list *el)
{
struct exclude *exc = NULL; /* undecided */
- int i;
+ int i, matched_negative_path = 0;
if (!el->nr)
return NULL; /* undefined */
@@ -937,7 +998,18 @@ static struct exclude *last_exclude_matching_from_list(const char *pathname,
exc = x;
break;
}
- }
+
+ if ((x->flags & EXC_FLAG_NEGATIVE) && !matched_negative_path &&
+ match_neg_path(pathname, pathlen, dtype, x->base,
+ x->baselen ? x->baselen - 1 : 0,
+ exclude, prefix, x->patternlen, x->flags))
+ matched_negative_path = 1;
+ }
+ if (exc &&
+ !(exc->flags & EXC_FLAG_NEGATIVE) &&
+ !(exc->flags & EXC_FLAG_NODIR) &&
+ matched_negative_path)
+ exc = NULL;
return exc;
}
diff --git a/t/t3001-ls-files-others-exclude.sh b/t/t3001-ls-files-others-exclude.sh
index 3fc484e..9de49a6 100755
--- a/t/t3001-ls-files-others-exclude.sh
+++ b/t/t3001-ls-files-others-exclude.sh
@@ -305,4 +305,24 @@ test_expect_success 'ls-files with "**" patterns and no slashes' '
test_cmp expect actual
'
+test_expect_success 'negative patterns' '
+ git init reinclude &&
+ (
+ cd reinclude &&
+ cat >.gitignore <<-\EOF &&
+ /foo
+ !foo/bar/bar
+ EOF
+ mkdir -p foo/bar &&
+ touch abc foo/def foo/bar/ghi foo/bar/bar &&
+ git ls-files -o --exclude-standard >../actual &&
+ cat >../expected <<-\EOF &&
+ .gitignore
+ abc
+ foo/bar/bar
+ EOF
+ test_cmp ../expected ../actual
+ )
+'
+
test_done
--
2.3.0.rc1.137.g477eb31
Nguyễn Thái Ngọc Duy