# 
# patch "ChangeLog"
#  from [b0f2be2bbdd4d66c404c825fd335d9c446597cdc]
#    to [f3568cb45c9228b7d12e25344f07558cfdfa599a]
# 
# patch "globish.cc"
#  from [42062864963a68b6d468f784dace238974658f3c]
#    to [c14030e9cdbf777c180f3324d26c18b25d29cf6e]
# 
# patch "globish.hh"
#  from [c43704114fc9a8866638686f3899749824c49179]
#    to [bcbaf2efddd720efb786f5f2843890071e42e3d8]
# 
--- ChangeLog
+++ ChangeLog
@@ -1,5 +1,11 @@
 2005-07-03  Nathaniel Smith  <address@hidden>
 
+	* globish.hh: Document the empty pattern as never matching.
+	* globish.cc (checked_globish_to_regex): Implement it.
+	(globish_matcher_test): Check it.
+
+2005-07-03  Nathaniel Smith  <address@hidden>
+
 	* monotone.texi (Network Service, Hooks):
 	* testsuite.at: 
 	* tests/t_netsync_permissions.at: 
--- globish.cc
+++ globish.cc
@@ -13,6 +13,9 @@
 //
 // Pattern tranformation:
 //
+// - As a special case, the empty pattern is translated to "$^", which cannot
+//   match any string.
+//
 // - Any character except those described below are copied as they are.
 // - The backslash (\) escapes the following character.  The escaping
 //   backslash is copied to the regex along with the following character.
@@ -45,12 +48,17 @@
 
   L(F("checked_globish_to_regex: input = '%s'\n") % glob);
 
+  if (glob == "")
+    {
+      regex = "$^";
+      // and the below loop will do nothing
+    }
   for (std::string::const_iterator i = glob.begin(); i != glob.end(); ++i)
     {
       char c = *i;
-
+      
       N(in_braces < 5, F("braces nested too deep in pattern '%s'") % glob);
-
+      
       switch(c)
         {
         case '*':
@@ -84,7 +92,7 @@
           break;
         }
     }
-
+  
   N(in_braces == 0,
     F("run-away brace expression in pattern '%s'") % glob);
 
@@ -196,6 +204,11 @@
     BOOST_CHECK(m("bfoobar"));
     BOOST_CHECK(!m("bfoobarcfoobar"));
   }
+  {
+    globish_matcher m(utf8("*"), utf8(""));
+    BOOST_CHECK(m("foo"));
+    BOOST_CHECK(m(""));
+  }
 }
 
 
--- globish.hh
+++ globish.hh
@@ -20,6 +20,9 @@
 //   {<anything1>,<anything2>,...} - match any of the given items
 // so like standard globs, except without [] character sets, and with {}
 // alternation.
+// the one strange thing is there is a special-case -- the empty pattern
+// matches nothing, not even the empty string.  this hardly ever matters, but
+// it's nice to have some way to say "don't exclude anything", for instance.
 
 #include <set>
 #include <string>