[PATCH]: =~ parsing littering pattern state fix

[Phil Pennock <zsh-workers+phil.pennock@xxxxxxxxxxxx>]

This is the problem reported by Mikael, wherein if an =~ condition is
followed by &&/|| then the following condition is prefixed with an
implicit negation.

The problem has been present since I added =~ and is a result of my not
understanding the parsing code and cargo-culting the layout, while
playing tricks on the system.

Per the comments in parse.c, in WC_COND, type == COND_MODI is followed
by name/left/right.  When consuming in evalcond(), COND_REGEX maps to an
implicit COND_MODI, which I modified to only consume the 'name' if an
overridename is not provided.  However, when cargo-culting, I followed
the pattern of ==/!= and also provided the pattern-number,
ecadd(ecnpats++) in the parsing.  This is the source of the error.

See attached.
-Phil

Index: Src/parse.c
===================================================================
RCS file: /home/cvsroot/zsh/Src/parse.c,v
retrieving revision 1.84
diff -a -u -p -r1.84 parse.c
--- Src/parse.c	14 Sep 2010 14:46:26 -0000	1.84
+++ Src/parse.c	9 Oct 2010 23:43:52 -0000
@@ -2172,10 +2172,11 @@ par_cond_triple(char *a, char *b, char *
 	ecadd(ecnpats++);
     } else if ((b[0] == Equals || b[0] == '=') &&
                (b[1] == '~' || b[1] == Tilde) && !b[2]) {
+        /* We become an implicit COND_MODI but do not provide the first
+	 * item, it's skipped */
 	ecadd(WCB_COND(COND_REGEX, 0));
 	ecstr(a);
 	ecstr(c);
-	ecadd(ecnpats++);
     } else if (b[0] == '-') {
 	if ((t0 = get_cond_num(b + 1)) > -1) {
 	    ecadd(WCB_COND(t0 + COND_NT, 0));
Index: Test/C02cond.ztst
===================================================================
RCS file: /home/cvsroot/zsh/Test/C02cond.ztst,v
retrieving revision 1.26
diff -a -u -p -r1.26 C02cond.ztst
--- Test/C02cond.ztst	19 Feb 2010 12:45:37 -0000	1.26
+++ Test/C02cond.ztst	9 Oct 2010 23:52:40 -0000
@@ -285,6 +285,19 @@ F:Failures in these cases do not indicat
 0:MATCH, MBEGIN, MEND, match, mbegin, mend
 >OK
 
+  (if zmodload -i zsh/regex 2>/dev/null; then
+    if [[ a =~ a && b == b ]]; then
+      print OK
+    else
+      print "regex =~ inverted following test"
+    fi
+  else
+    # not a test error
+    print OK
+  fi)
+0:regex infix operator should not invert following conditions
+>OK
+
   [[ -fail badly ]]
 2:Error message for unknown prefix condition
 ?(eval):1: unknown condition: -fail