Replace %push-parser' and %push-pull-parser' with

`%define push_pull "push"' and `%define push_pull "both"'.
`%define push_pull "pull"' is the default.
* doc/bison.texinfo (Push Decl, Push Parser Function,
Pull Parser Function, Parser Create Function, Parser Delete Function):
Update declarations.
(Decl Summary, Table of Symbols): Replace %push-parser and
%push-pull-parser entries with a %define push_pull entry.
* data/bison.m4 (b4_percent_define_check_values): New macro.
(b4_pull_if, b4_push_if, b4_use_push_for_pull_if): Move these
definitions...
* data/c.m4 (b4_identification): ... and the YYPUSH and YYPULL cpp
definitions...
* data/push.c: ... to here and compute them from the value of the
%define variable push_pull.
* data/c-skel.m4: Instead of choosing the push.c skeleton for push
parsing requests here...
* data/yacc.c: ... hack this to switch to push.c any time
b4_use_push_pull_flag or the %define variable push_pull is set.  This
will go away when we mv push.c yacc.c.
* data/c++-skel.m4, data/glr.c, data/java-skel.m4: Don't report that
push parsing is not supported since unused %define variables are
reported anyway.
* src/getargs.c, src/getargs.h (pull_parser, push_parser): Remove.
* src/muscle_tab.h (muscle_percent_define_check_values): Update
comments for consistency with b4_percent_define_check_values.
* src/output.c (prepare): Don't insert b4_pull_flag and b4_push_flag
muscles.
* src/parse-gram.y (PERCENT_PUSH_PARSER, PERCENT_PUSH_PULL_PARSER):
Remove.
(prologue_declaration): Remove %push-parser and %push-pull-parser
rules.
* src/scan-gram.l (%push-parser, %push-pull-parser): Remove rules.
* tests/calc.at: Update declarations.
* tests/input.at (%define enum variables): New test case.
* tests/push.at (Push Parsing: Memory Leak for Early Deletion): Update
declaration.
(Push Parsing: Multiple impure instances): Update declaration.
(Push Parsing: Unsupported Skeletons): New test case.
* tests/torture.at (Exploding the Stack Size with Alloca): Update
declaration.
(Exploding the Stack Size with Malloc): Update declaration.

tests/calc.at

@@ -560,7 +560,7 @@ AT_CHECK_CALC_LALR([%yacc])
 AT_CHECK_CALC_LALR([%error-verbose])
 
 AT_CHECK_CALC_LALR([%pure-parser %locations])
-AT_CHECK_CALC_LALR([%push-pull-parser %pure-parser %locations])
+AT_CHECK_CALC_LALR([%define push_pull "both" %pure-parser %locations])
 AT_CHECK_CALC_LALR([%error-verbose %locations])
 
 AT_CHECK_CALC_LALR([%error-verbose %locations %defines %name-prefix "calc" %verbose %yacc])
@@ -569,7 +569,7 @@ AT_CHECK_CALC_LALR([%debug])
 AT_CHECK_CALC_LALR([%error-verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc])
 
 AT_CHECK_CALC_LALR([%pure-parser %error-verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc])
-AT_CHECK_CALC_LALR([%push-pull-parser %pure-parser %error-verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc])
+AT_CHECK_CALC_LALR([%define push_pull "both" %pure-parser %error-verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc])
 
 AT_CHECK_CALC_LALR([%pure-parser %error-verbose %debug %locations %defines %name-prefix "calc" %verbose %yacc %parse-param {semantic_value *result} %parse-param {int *count}])
 

tests/input.at

@@ -822,10 +822,10 @@ input.y:5.9-16: warning: %define variable `special2' is not used
 AT_CLEANUP
 
 ## --------------------------- ##
-## Boolean %define variables.  ##
+## %define Boolean variables.  ##
 ## --------------------------- ##
 
-AT_SETUP([Boolean %define variables])
+AT_SETUP([[%define Boolean variables]])
 
 AT_DATA([Input.y],
 [[%language "Java"
@@ -840,3 +840,21 @@ AT_CHECK([[bison Input.y]], [1], [],
 ]])
 
 AT_CLEANUP
+
+## ------------------------ ##
+## %define enum variables.  ##
+## ------------------------ ##
+
+AT_SETUP([[%define enum variables]])
+
+AT_DATA([[input.y]],
+[[%define push_pull "neither"
+%%
+start: ;
+]])
+
+AT_CHECK([[bison input.y]], [1], [],
+[[input.y:1.9-17: invalid value for %define variable `push_pull': `neither'
+]])
+
+AT_CLEANUP

tests/push.at

@@ -33,7 +33,7 @@ AT_DATA_GRAMMAR([[input.y]],
   void yyerror (char const *msg);
 %}
 
-%pure-parser %push-parser
+%pure-parser %define push_pull "push"
 
 %%
 
@@ -77,7 +77,6 @@ AT_PARSER_CHECK([[./input]])
 
 AT_CLEANUP
 
-
 ## ----------------------------------------- ##
 ## Push Parsing: Multiple impure instances.  ##
 ## ----------------------------------------- ##
@@ -93,7 +92,7 @@ AT_DATA_GRAMMAR([[input.y]],
   int yylex (void);
 %}
 
-%push-pull-parser
+%define push_pull "both"
 
 %%
 
@@ -150,3 +149,22 @@ cannot allocate multiple impure push-parser instances
 ]])
 
 AT_CLEANUP
+
+## ------------------------------------- ##
+## Push Parsing: Unsupported Skeletons.  ##
+## ------------------------------------- ##
+
+AT_SETUP([[Push Parsing: Unsupported Skeletons]])
+
+AT_DATA([[input.y]],
+[[%glr-parser
+%define push_pull "push"
+%%
+start: ;
+]])
+
+AT_CHECK([[bison input.y]], [0], [],
+[[input.y:2.9-17: warning: %define variable `push_pull' is not used
+]])
+
+AT_CLEANUP

tests/torture.at

@@ -496,7 +496,7 @@ AT_PARSER_CHECK([./input 10000], 2, [], [ignore],
 # just helps guarantee we don't let the YYSTACK_USE_ALLOCA feature affect
 # push parsers.
 AT_DATA_STACK_TORTURE([AT_USE_ALLOCA],
-[[%push-pull-parser
+[[%define push_pull "both"
 ]])
 AT_PARSER_CHECK([./input 20], 0, [], [ignore],
                 [[VALGRIND_OPTS="$VALGRIND_OPTS --log-fd=1"]])
@@ -534,7 +534,7 @@ AT_PARSER_CHECK([./input 10000], 2, [], [ignore],
                 [[VALGRIND_OPTS="$VALGRIND_OPTS --log-fd=1"]])
 
 AT_DATA_STACK_TORTURE([AT_USE_ALLOCA],
-[[%push-pull-parser
+[[%define push_pull "both"
 ]])
 AT_PARSER_CHECK([./input 20], 0, [], [ignore],
                 [[VALGRIND_OPTS="$VALGRIND_OPTS --log-fd=1"]])