[PATCH v4 08/16] pathspec: always show mnemonic and name in unsupported_magic

[Brandon Williams <bmwill@google.com>]

For better clarity, always show the mnemonic and name of the unsupported
magic being used.  This lets users have a more clear understanding of
what magic feature isn't supported.  And if they supplied a mnemonic,
the user will be told what its corresponding name is which will allow
them to more easily search the man pages for that magic type.

This also avoids passing an extra parameter around the pathspec
initialization code.

Signed-off-by: Brandon Williams <bmwill@google.com>
---
 pathspec.c | 24 +++++++++---------------
 1 file changed, 9 insertions(+), 15 deletions(-)

diff --git a/pathspec.c b/pathspec.c
index b9a3819d6..ee87494c7 100644
--- a/pathspec.c
+++ b/pathspec.c
@@ -101,9 +101,7 @@ static void prefix_short_magic(struct strbuf *sb, int prefixlen,
  * the prefix part must always match literally, and a single stupid
  * string cannot express such a case.
  */
-static unsigned prefix_pathspec(struct pathspec_item *item,
-				unsigned *p_short_magic,
-				unsigned flags,
+static unsigned prefix_pathspec(struct pathspec_item *item, unsigned flags,
 				const char *prefix, int prefixlen,
 				const char *elt)
 {
@@ -210,7 +208,6 @@ static unsigned prefix_pathspec(struct pathspec_item *item,
 	}
 
 	magic |= short_magic;
-	*p_short_magic = short_magic;
 
 	/* --noglob-pathspec adds :(literal) _unless_ :(glob) is specified */
 	if (noglob_global && !(magic & PATHSPEC_GLOB))
@@ -329,8 +326,7 @@ static int pathspec_item_cmp(const void *a_, const void *b_)
 }
 
 static void NORETURN unsupported_magic(const char *pattern,
-				       unsigned magic,
-				       unsigned short_magic)
+				       unsigned magic)
 {
 	struct strbuf sb = STRBUF_INIT;
 	int i;
@@ -339,9 +335,11 @@ static void NORETURN unsupported_magic(const char *pattern,
 		if (!(magic & m->bit))
 			continue;
 		if (sb.len)
-			strbuf_addch(&sb, ' ');
-		if (short_magic & m->bit)
-			strbuf_addf(&sb, "'%c'", m->mnemonic);
+			strbuf_addstr(&sb, ", ");
+
+		if (m->mnemonic)
+			strbuf_addf(&sb, "'%s' (mnemonic: '%c')",
+				    m->name, m->mnemonic);
 		else
 			strbuf_addf(&sb, "'%s'", m->name);
 	}
@@ -413,11 +411,9 @@ void parse_pathspec(struct pathspec *pathspec,
 	prefixlen = prefix ? strlen(prefix) : 0;
 
 	for (i = 0; i < n; i++) {
-		unsigned short_magic;
 		entry = argv[i];
 
-		item[i].magic = prefix_pathspec(item + i, &short_magic,
-						flags,
+		item[i].magic = prefix_pathspec(item + i, flags,
 						prefix, prefixlen, entry);
 		if ((flags & PATHSPEC_LITERAL_PATH) &&
 		    !(magic_mask & PATHSPEC_LITERAL))
@@ -425,9 +421,7 @@ void parse_pathspec(struct pathspec *pathspec,
 		if (item[i].magic & PATHSPEC_EXCLUDE)
 			nr_exclude++;
 		if (item[i].magic & magic_mask)
-			unsupported_magic(entry,
-					  item[i].magic & magic_mask,
-					  short_magic);
+			unsupported_magic(entry, item[i].magic & magic_mask);
 
 		if ((flags & PATHSPEC_SYMLINK_LEADING_PATH) &&
 		    has_symlink_leading_path(item[i].match, item[i].len)) {
-- 
2.11.0.390.gc69c2f50cf-goog