check for delimiter_depth being 0 before popping off the stack (reset_parser resets it); make EOFs while reading here-doc delimiters sticky; when reading arith command, push back a character after the first closing paren that isn't a second close paren to fix backslash issue

tests/read.right

@@ -52,11 +52,6 @@ a = abc
 <$'spring\375'>
 <summer>
 <automn>
-<winter>
-<$'spring\375'>
-<$'\277summer'>
-<$'\277'>
-<automn>
 timeout 1: ok
 unset or null 1
 timeout 2: ok

tests/read1.sub

@@ -44,14 +44,16 @@ printf '%b\0' winter spring 'summer\0200apple\0200banana\0200cherry' automn |
 printf '%b\200' winter 'spring\0375' summer automn |
   while IFS= read -rd $'\200' season; do LC_ALL=C printf "<%q>\n" "$season"; done
 
-: ${TMPDIR:=/tmp}
-INFILE=$TMPDIR/read-in-$$
-printf '%b\243' winter 'spring\0375' '\0277summer' '\0277' automn > $INFILE
+# this test is encoding-dependent, and varies from system to system
+#: ${TMPDIR:=/tmp}
+#INFILE=$TMPDIR/read-in-$$
+#printf '%b\243' winter 'spring\0375' '\0277summer' '\0277' automn > $INFILE
+#
+#LANG=zh_HK.big5hkscs
+#while IFS= read -rd $'\243' season; do
+#	LC_ALL=C printf "<%q>\n" "$season"
+#done < $INFILE
+#
+#rm -f $INFILE
 
-LANG=zh_HK.big5hkscs
-while IFS= read -rd $'\243' season; do
-	LC_ALL=C printf "<%q>\n" "$season"
-done < $INFILE
-
-rm -f $INFILE
 exit 0