Re: [PATCH] pathspec: rename per-item field has_wildcard to use_wildcard

[Junio C Hamano <gitster@pobox.com>]

Junio C Hamano <gitster@pobox.com> writes:

> I am actually tempted to add Michael's hack to get_pathspec() only to
> support the "from the top" (and error out with any other magic---as the
> approach without a proper restructuring will not work with anything but
> that particular magic), to get the "add -u" topic going, and let you (or
> other people who are interested in the pathspec rationalization) later fix
> it up just a small part of existing issues.

Just a heads-up; it would look like this (no docs, tests, nor "add -u"
message updates yet).  The entries other than "top" should not be in the
final version but I just wanted to make sure that the extensibility would
look sane.


 setup.c |  101 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 99 insertions(+), 2 deletions(-)

diff --git a/setup.c b/setup.c
index 03cd84f..704a930 100644
--- a/setup.c
+++ b/setup.c
@@ -126,6 +126,104 @@ void verify_non_filename(const char *prefix, const char *arg)
 	    "Use '--' to separate filenames from revisions", arg);
 }
 
+/*
+ * Magic pathspec
+ *
+ * NEEDSWORK: These need to be moved to dir.h or even to a new
+ * pathspec.h when we restructure get_pathspec() users to use the
+ * "struct pathspec" interface.
+ */
+#define PATHSPEC_FROMTOP    (1<<0)
+#define PATHSPEC_NOGLOB     (1<<1)
+#define PATHSPEC_ICASE      (1<<2)
+#define PATHSPEC_RECURSIVE  (1<<3)
+#define PATHSPEC_REGEXP     (1<<4)
+
+struct pathspec_magic {
+	unsigned bit;
+	char mnemonic; /* cannot be ':'! */
+	const char *name;
+} pathspec_magic[] = {
+	{ PATHSPEC_FROMTOP, '/', "top" },
+	{ PATHSPEC_NOGLOB, '!', "noglob" },
+	{ PATHSPEC_ICASE, '\0', "icase" },
+	{ PATHSPEC_RECURSIVE, '*', "recursive" },
+	{ PATHSPEC_REGEXP, '\0', "regexp" },
+};
+
+/*
+ * Take an element of a pathspec and check for magic signatures.
+ * Append the result to the prefix.
+ *
+ * For now, we only parse the syntax and throw out anything other than
+ * "top" magic.
+ *
+ * NEEDSWORK: This needs to be rewritten when we start migrating
+ * get_pathspec() users to use the "struct pathspec" interface.  For
+ * example, a pathspec element may be marked as case-insensitive, but
+ * the prefix part must always match literally, and a single stupid
+ * string cannot express such a case.
+ */
+const char *prefix_pathspec(const char *prefix, int prefixlen, const char *elt)
+{
+	unsigned magic = 0;
+	const char *copyfrom = elt;
+	int i;
+
+	if (elt[0] != ':') {
+		; /* nothing to do */
+	} else if (elt[1] == '(') {
+		/* longhand */
+		const char *nextat;
+		for (copyfrom = elt + 2;
+		     *copyfrom && *copyfrom != ')';
+		     copyfrom = nextat) {
+			size_t len = strcspn(copyfrom, ",)");
+			if (copyfrom[len] == ')')
+				nextat = copyfrom + len;
+			else
+				nextat = copyfrom + len + 1;
+			if (!len)
+				continue;
+			for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
+				if (strlen(pathspec_magic[i].name) == len &&
+				    !strncmp(pathspec_magic[i].name, copyfrom, len)) {
+					magic |= pathspec_magic[i].bit;
+					break;
+				}
+			if (ARRAY_SIZE(pathspec_magic) <= i)
+				die("Invalid pathspec magic '%.*s' in '%s'",
+				    (int) len, copyfrom, elt);
+		}
+		if (*copyfrom == ')')
+			copyfrom++;
+	} else {
+		/* shorthand */
+		for (copyfrom = elt + 1;
+		     *copyfrom && *copyfrom != ':';
+		     copyfrom++) {
+			char ch = *copyfrom;
+			for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
+				if (pathspec_magic[i].mnemonic == ch) {
+					magic |= pathspec_magic[i].bit;
+					break;
+				}
+			if (ARRAY_SIZE(pathspec_magic) <= i)
+				break;
+		}
+		if (*copyfrom == ':')
+			copyfrom++;
+	}
+
+	if (magic & ~(PATHSPEC_FROMTOP))
+		die("Unsupported pathspec magic in '%s'", elt);
+
+	if (magic & PATHSPEC_FROMTOP)
+		return xstrdup(copyfrom);
+	else
+		return prefix_path(prefix, prefixlen, copyfrom);
+}
+
 const char **get_pathspec(const char *prefix, const char **pathspec)
 {
 	const char *entry = *pathspec;
@@ -147,8 +245,7 @@ const char **get_pathspec(const char *prefix, const char **pathspec)
 	dst = pathspec;
 	prefixlen = prefix ? strlen(prefix) : 0;
 	while (*src) {
-		const char *p = prefix_path(prefix, prefixlen, *src);
-		*(dst++) = p;
+		*(dst++) = prefix_pathspec(prefix, prefixlen, *src);
 		src++;
 	}
 	*dst = NULL;