* doc/bison.texinfo (Stack Overflow): xref to Recursion.

[bison.git] / tests / calc.at

# Checking the output filenames.                         -*- Autotest -*-
# Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
# 02111-1307, USA.

AT_BANNER([[Simple Calculator.]])

## ---------------------------------------------------- ##
## Compile the grammar described in the documentation.  ##
## ---------------------------------------------------- ##


# ------------------------- #
# Helping Autotest macros.  #
# ------------------------- #


# _AT_DATA_CALC_Y($1, $2, $3, [CPP-DIRECTIVES])
# ---------------------------------------------
# Produce `calc.y'.  Don't call this macro directly, because it contains
# some occurrences of `$1' etc. which will be interpreted by m4.  So
# you should call it with $1, $2, and $3 as arguments, which is what
# AT_DATA_CALC_Y does.
m4_define([_AT_DATA_CALC_Y],
[m4_if([$1$2$3], $[1]$[2]$[3], [],
       [m4_fatal([$0: Invalid arguments: $@])])dnl
AT_DATA([calc.y],
[[/* Infix notation calculator--calc */

%{
#include <config.h>
/* We don't need a perfect malloc for these tests. */
#undef malloc
#include <stdio.h>

#if STDC_HEADERS
# include <stdlib.h>
# include <string.h>
#else
char *strcat(char *dest, const char *src);
#endif
#include <ctype.h>

static int power (int base, int exponent);
static void yyerror (const char *s);
static int yylex (void);
static int yygetc (void);
static void yyungetc (int c);

extern void perror (const char *s);

/* Exercise pre-prologue dependency to %union.  */
typedef int value_t;

%}

/* Exercise %union. */
%union
{
  value_t ival;
};

/* Bison Declarations */
%token CALC_EOF 0 "end of file"
%token <ival> NUM "number"
%type  <ival> exp

%nonassoc '=' /* comparison	       */
%left '-' '+'
%left '*' '/'
%left NEG     /* negation--unary minus */
%right '^'    /* exponentiation        */

]$4[

/* Grammar follows */
%%
input:
  line
| input line
;

line:
  '\n'      {}
| exp '\n'  {}
;

exp:
  NUM                { $$ = $1;             }
| exp '=' exp
  {
     if ($1 != $3)
       fprintf (stderr, "calc: error: %d != %d\n", $1, $3);
     $$ = $1 == $3;
  }
| exp '+' exp        { $$ = $1 + $3;        }
| exp '-' exp        { $$ = $1 - $3;        }
| exp '*' exp        { $$ = $1 * $3;        }
| exp '/' exp        { $$ = $1 / $3;        }
| '-' exp  %prec NEG { $$ = -$2;            }
| exp '^' exp        { $$ = power ($1, $3); }
| '(' exp ')'        { $$ = $2;             }
| '(' error ')'      { $$ = 0;              }
;
%%
/* The input. */
FILE *yyin;

static void
yyerror (const char *s)
{
#if YYLSP_NEEDED
  fprintf (stderr, "%d.%d-%d.%d: ",
	   yylloc.first_line, yylloc.first_column,
	   yylloc.last_line, yylloc.last_column);
#endif
  fprintf (stderr, "%s\n", s);
}


#if YYLSP_NEEDED
static YYLTYPE last_yylloc;
#endif
static int
yygetc (void)
{
  int res = getc (yyin);
#if YYLSP_NEEDED
  last_yylloc = yylloc;
  if (res == '\n')
    {
      yylloc.last_line++;
      yylloc.last_column = 1;
    }
  else
    yylloc.last_column++;
#endif
  return res;
}


static void
yyungetc (int c)
{
#if YYLSP_NEEDED
  /* Wrong when C == `\n'. */
  yylloc = last_yylloc;
#endif
  ungetc (c, yyin);
}

static int
read_signed_integer (void)
{
  int c = yygetc ();
  int sign = 1;
  int n = 0;

  if (c == '-')
    {
      c = yygetc ();
      sign = -1;
    }

  while (isdigit (c))
    {
      n = 10 * n + (c - '0');
      c = yygetc ();
    }

  yyungetc (c);

  return sign * n;
}



/*---------------------------------------------------------------.
| Lexical analyzer returns an integer on the stack and the token |
| NUM, or the ASCII character read if not a number.  Skips all   |
| blanks and tabs, returns 0 for EOF.                            |
`---------------------------------------------------------------*/

static int
yylex (void)
{
  int c;

#if YYLSP_NEEDED
  yylloc.first_column = yylloc.last_column;
  yylloc.first_line = yylloc.last_line;
#endif

  /* Skip white space.  */
  while ((c = yygetc ()) == ' ' || c == '\t')
    {
#if YYLSP_NEEDED
      yylloc.first_column = yylloc.last_column;
      yylloc.first_line = yylloc.last_line;
#endif
    }

  /* process numbers   */
  if (c == '.' || isdigit (c))
    {
      yyungetc (c);
      yylval.ival = read_signed_integer ();
      return NUM;
    }

  /* Return end-of-file.  */
  if (c == EOF)
    return CALC_EOF;

  /* Return single chars. */
  return c;
}

static int
power (int base, int exponent)
{
  int res = 1;
  if (exponent < 0)
    exit (1);
  for (/* Niente */; exponent; --exponent)
    res *= base;
  return res;
}

int
main (int argc, const char **argv)
{
  yyin = NULL;

  if (argc == 2)
    yyin = fopen (argv[1], "r");
  else
    yyin = stdin;

  if (!yyin)
    {
      perror (argv[1]);
      exit (1);
    }

#if YYDEBUG
  yydebug = 1;
#endif
#if YYLSP_NEEDED
  yylloc.last_column = 1;
  yylloc.last_line = 1;
#endif
  yyparse ();
  return 0;
}
]])
])# _AT_DATA_CALC_Y


# AT_DATA_CALC_Y([BISON-OPTIONS])
# -------------------------------
# Produce `calc.y'.
m4_define([AT_DATA_CALC_Y],
[_AT_DATA_CALC_Y($[1], $[2], $[3],
                 [m4_bmatch([$1], [--yyerror-verbose],
                            [[%error-verbose]])])])



# _AT_CHECK_CALC(BISON-OPTIONS, INPUT, [NUM-STDERR-LINES = 0])
# ------------------------------------------------------------
# Run `calc' on INPUT and expect no STDOUT nor STDERR.
#
# If BISON-OPTIONS contains `--debug', then NUM-STDERR-LINES is the number
# of expected lines on stderr.
m4_define([_AT_CHECK_CALC],
[AT_DATA([[input]],
[[$2
]])
AT_PARSER_CHECK([./calc input], 0, [], [stderr])dnl
AT_CHECK([wc -l <stderr | sed 's/[[^0-9]]//g'], 0,
         [m4_bmatch([$1], [--debug],
                    [$3], [0])
])
])


# _AT_CHECK_CALC_ERROR(BISON-OPTIONS, INPUT, [NUM-DEBUG-LINES],
#                      [ERROR-LOCATION], [IF-YYERROR-VERBOSE])
# ------------------------------------------------------------
# Run `calc' on INPUT, and expect a `parse error' message.
#
# If INPUT starts with a slash, it is used as absolute input file name,
# otherwise as contents.
#
# If BISON-OPTIONS contains `--location', then make sure the ERROR-LOCATION
# is correctly output on stderr.
#
# If BISON-OPTIONS contains `--yyerror-verbose', then make sure the
# IF-YYERROR-VERBOSE message is properly output after `parse error, '
# on STDERR.
#
# If BISON-OPTIONS contains `--debug', then NUM-STDERR-LINES is the number
# of expected lines on stderr.
m4_define([_AT_CHECK_CALC_ERROR],
[m4_bmatch([$2], [^/],
           [AT_PARSER_CHECK([./calc $2], 0, [], [stderr])],
           [AT_DATA([[input]],
[[$2
]])
AT_PARSER_CHECK([./calc input], 0, [], [stderr])])

m4_bmatch([$1], [--debug],
[AT_CHECK([wc -l <stderr | sed 's/[[^0-9]]//g'], 0, [$3
])])

# Normalize the observed and expected error messages, depending upon the
# options.
# 1. Remove the traces from observed.
sed '/^Starting/d
/^Entering/d
/^Reading/d
/^Reducing/d
/^Shifting/d
/^state/d
/^Error:/d
/^Next/d
/^Discarding/d
/^yydestructor:/d' stderr >at-stderr
mv at-stderr stderr
# 2. Create the reference error message.
AT_DATA([[expout]],
[$4
])
# 3. If locations are not used, remove them.
m4_bmatch([$1], [--location], [],
[[sed 's/^[-0-9.]*: //' expout >at-expout
mv at-expout expout]])
# 4. If error-verbose is not used, strip the`, unexpected....' part.
m4_bmatch([$1], [--yyerror-verbose], [],
[[sed 's/parse error, .*$/parse error/' expout >at-expout
mv at-expout expout]])
# 5. Check
AT_CHECK([cat stderr], 0, [expout])
])


# AT_CHECK_CALC([BISON-OPTIONS], [PARSER-EXPECTED-STDERR])
# --------------------------------------------------------
# Start a testing chunk which compiles `calc' grammar with
# BISON-OPTIONS, and performs several tests over the parser.
m4_define([AT_CHECK_CALC],
[# We use integers to avoid dependencies upon the precision of doubles.
AT_SETUP([Calculator $1])

AT_DATA_CALC_Y([$1])

# Specify the output files to avoid problems on different file systems.
AT_CHECK([bison calc.y -o calc.c m4_bpatsubst([$1], [--yyerror-verbose])],
         [0], [], [])

AT_COMPILE([calc])

# Test the priorities.
_AT_CHECK_CALC([$1],
[1 + 2 * 3 = 7
1 + 2 * -3 = -5

-1^2 = -1
(-1)^2 = 1

---1 = -1

1 - 2 - 3 = -4
1 - (2 - 3) = 2

2^2^3 = 256
(2^2)^3 = 64], [486])

# Some parse errors.
_AT_CHECK_CALC_ERROR([$1], [0 0], [11],
                     [1.3-1.4: parse error, unexpected "number"])
_AT_CHECK_CALC_ERROR([$1], [1//2], [15],
                     [1.3-1.4: parse error, unexpected '/', expecting "number" or '-' or '('])
_AT_CHECK_CALC_ERROR([$1], [error], [4],
                     [1.1-1.2: parse error, unexpected $undefined, expecting "number" or '-' or '\n' or '('])
_AT_CHECK_CALC_ERROR([$1], [1 = 2 = 3], [22],
                     [1.7-1.8: parse error, unexpected '='])
_AT_CHECK_CALC_ERROR([$1],
                     [
+1],
                     [14],
                     [2.1-2.2: parse error, unexpected '+'])
# Exercise error messages with EOF: work on an empty file.
_AT_CHECK_CALC_ERROR([$1], [/dev/null], [4],
                     [1.1-1.2: parse error, unexpected "end of file", expecting "number" or '-' or '\n' or '('])

# Exercise the error token: without it, we die at the first error,
# hence be sure i. to have several errors, ii. to test the action
# associated to `error'.
_AT_CHECK_CALC_ERROR([$1], [(1 ++ 2) + (0 0) = 1], [82],
[1.5-1.6: parse error, unexpected '+', expecting "number" or '-' or '('
1.15-1.16: parse error, unexpected "number"
calc: error: 0 != 1])

# Add a studid example demonstrating that Bison can further improve the
# error message.  FIXME: Fix this ridiculous message.
_AT_CHECK_CALC_ERROR([$1], [()], [21],
[1.2-1.3: parse error, unexpected ')', expecting "number" or '-' or '('])

AT_CLEANUP
])# AT_CHECK_CALC




# ------------------ #
# Test the parsers.  #
# ------------------ #

AT_CHECK_CALC()

AT_CHECK_CALC([--defines])
AT_CHECK_CALC([--locations])
AT_CHECK_CALC([--name-prefix=calc])
AT_CHECK_CALC([--verbose])
AT_CHECK_CALC([--yacc])
AT_CHECK_CALC([--yyerror-verbose])

AT_CHECK_CALC([--locations --yyerror-verbose])

AT_CHECK_CALC([--defines --locations --name-prefix=calc --verbose --yacc --yyerror-verbose])

AT_CHECK_CALC([--debug])
AT_CHECK_CALC([--debug --defines --locations --name-prefix=calc --verbose --yacc --yyerror-verbose])