mediawiki-extensions-Parser.../includes/ExprParser.php
libraryupgrader 7df8411050 build: Updating composer dependencies
* mediawiki/mediawiki-codesniffer: 35.0.0 → 36.0.0
  The following sniffs now pass and were enabled:
  * MediaWiki.Commenting.PropertyDocumentation.MissingDocumentationPublic

* php-parallel-lint/php-parallel-lint: 1.2.0 → 1.3.0

Change-Id: Ifaca144ccfd753ea00d1dbba0d12941b0050e2a4
2021-05-04 08:49:27 +00:00

680 lines
19 KiB
PHP
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<?php
/**
* 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 of the License, 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
namespace MediaWiki\Extensions\ParserFunctions;
use UtfNormal\Validator;
class ExprParser {
// Character classes
private const EXPR_WHITE_CLASS = " \t\r\n";
private const EXPR_NUMBER_CLASS = '0123456789.';
// Token types
private const EXPR_WHITE = 1;
private const EXPR_NUMBER = 2;
private const EXPR_NEGATIVE = 3;
private const EXPR_POSITIVE = 4;
private const EXPR_PLUS = 5;
private const EXPR_MINUS = 6;
private const EXPR_TIMES = 7;
private const EXPR_DIVIDE = 8;
private const EXPR_MOD = 9;
private const EXPR_OPEN = 10;
private const EXPR_CLOSE = 11;
private const EXPR_AND = 12;
private const EXPR_OR = 13;
private const EXPR_NOT = 14;
private const EXPR_EQUALITY = 15;
private const EXPR_LESS = 16;
private const EXPR_GREATER = 17;
private const EXPR_LESSEQ = 18;
private const EXPR_GREATEREQ = 19;
private const EXPR_NOTEQ = 20;
private const EXPR_ROUND = 21;
private const EXPR_EXPONENT = 22;
private const EXPR_SINE = 23;
private const EXPR_COSINE = 24;
private const EXPR_TANGENS = 25;
private const EXPR_ARCSINE = 26;
private const EXPR_ARCCOS = 27;
private const EXPR_ARCTAN = 28;
private const EXPR_EXP = 29;
private const EXPR_LN = 30;
private const EXPR_ABS = 31;
private const EXPR_FLOOR = 32;
private const EXPR_TRUNC = 33;
private const EXPR_CEIL = 34;
private const EXPR_POW = 35;
private const EXPR_PI = 36;
private const EXPR_FMOD = 37;
private const EXPR_SQRT = 38;
private const MAX_STACK_SIZE = 100;
private const PRECEDENCE = [
self::EXPR_NEGATIVE => 10,
self::EXPR_POSITIVE => 10,
self::EXPR_EXPONENT => 10,
self::EXPR_SINE => 9,
self::EXPR_COSINE => 9,
self::EXPR_TANGENS => 9,
self::EXPR_ARCSINE => 9,
self::EXPR_ARCCOS => 9,
self::EXPR_ARCTAN => 9,
self::EXPR_EXP => 9,
self::EXPR_LN => 9,
self::EXPR_ABS => 9,
self::EXPR_FLOOR => 9,
self::EXPR_TRUNC => 9,
self::EXPR_CEIL => 9,
self::EXPR_NOT => 9,
self::EXPR_SQRT => 9,
self::EXPR_POW => 8,
self::EXPR_TIMES => 7,
self::EXPR_DIVIDE => 7,
self::EXPR_MOD => 7,
self::EXPR_FMOD => 7,
self::EXPR_PLUS => 6,
self::EXPR_MINUS => 6,
self::EXPR_ROUND => 5,
self::EXPR_EQUALITY => 4,
self::EXPR_LESS => 4,
self::EXPR_GREATER => 4,
self::EXPR_LESSEQ => 4,
self::EXPR_GREATEREQ => 4,
self::EXPR_NOTEQ => 4,
self::EXPR_AND => 3,
self::EXPR_OR => 2,
self::EXPR_PI => 0,
self::EXPR_OPEN => -1,
self::EXPR_CLOSE => -1,
];
private const NAMES = [
self::EXPR_NEGATIVE => '-',
self::EXPR_POSITIVE => '+',
self::EXPR_NOT => 'not',
self::EXPR_TIMES => '*',
self::EXPR_DIVIDE => '/',
self::EXPR_MOD => 'mod',
self::EXPR_FMOD => 'fmod',
self::EXPR_PLUS => '+',
self::EXPR_MINUS => '-',
self::EXPR_ROUND => 'round',
self::EXPR_EQUALITY => '=',
self::EXPR_LESS => '<',
self::EXPR_GREATER => '>',
self::EXPR_LESSEQ => '<=',
self::EXPR_GREATEREQ => '>=',
self::EXPR_NOTEQ => '<>',
self::EXPR_AND => 'and',
self::EXPR_OR => 'or',
self::EXPR_EXPONENT => 'e',
self::EXPR_SINE => 'sin',
self::EXPR_COSINE => 'cos',
self::EXPR_TANGENS => 'tan',
self::EXPR_ARCSINE => 'asin',
self::EXPR_ARCCOS => 'acos',
self::EXPR_ARCTAN => 'atan',
self::EXPR_LN => 'ln',
self::EXPR_EXP => 'exp',
self::EXPR_ABS => 'abs',
self::EXPR_FLOOR => 'floor',
self::EXPR_TRUNC => 'trunc',
self::EXPR_CEIL => 'ceil',
self::EXPR_POW => '^',
self::EXPR_PI => 'pi',
self::EXPR_SQRT => 'sqrt',
];
private const WORDS = [
'mod' => self::EXPR_MOD,
'fmod' => self::EXPR_FMOD,
'and' => self::EXPR_AND,
'or' => self::EXPR_OR,
'not' => self::EXPR_NOT,
'round' => self::EXPR_ROUND,
'div' => self::EXPR_DIVIDE,
'e' => self::EXPR_EXPONENT,
'sin' => self::EXPR_SINE,
'cos' => self::EXPR_COSINE,
'tan' => self::EXPR_TANGENS,
'asin' => self::EXPR_ARCSINE,
'acos' => self::EXPR_ARCCOS,
'atan' => self::EXPR_ARCTAN,
'exp' => self::EXPR_EXP,
'ln' => self::EXPR_LN,
'abs' => self::EXPR_ABS,
'trunc' => self::EXPR_TRUNC,
'floor' => self::EXPR_FLOOR,
'ceil' => self::EXPR_CEIL,
'pi' => self::EXPR_PI,
'sqrt' => self::EXPR_SQRT,
];
/**
* Evaluate a mathematical expression
*
* The algorithm here is based on the infix to RPN algorithm given in
* http://montcs.bloomu.edu/~bobmon/Information/RPN/infix2rpn.shtml
* It's essentially the same as Dijkstra's shunting yard algorithm.
* @param string $expr
* @return string
* @throws ExprError
*/
public function doExpression( $expr ) {
$operands = [];
$operators = [];
# Unescape inequality operators
$expr = strtr( $expr, [ '&lt;' => '<', '&gt;' => '>',
'&minus;' => '-', '' => '-' ] );
$p = 0;
$end = strlen( $expr );
$expecting = 'expression';
$name = '';
while ( $p < $end ) {
if ( count( $operands ) > self::MAX_STACK_SIZE || count( $operators ) > self::MAX_STACK_SIZE ) {
throw new ExprError( 'stack_exhausted' );
}
$char = $expr[$p];
$char2 = substr( $expr, $p, 2 );
// Mega if-elseif-else construct
// Only binary operators fall through for processing at the bottom, the rest
// finish their processing and continue
// First the unlimited length classes
// @phan-suppress-next-line PhanParamSuspiciousOrder false positive
if ( strpos( self::EXPR_WHITE_CLASS, $char ) !== false ) {
// Whitespace
$p += strspn( $expr, self::EXPR_WHITE_CLASS, $p );
continue;
// @phan-suppress-next-line PhanParamSuspiciousOrder false positive
} elseif ( strpos( self::EXPR_NUMBER_CLASS, $char ) !== false ) {
// Number
if ( $expecting !== 'expression' ) {
throw new ExprError( 'unexpected_number' );
}
// Find the rest of it
$length = strspn( $expr, self::EXPR_NUMBER_CLASS, $p );
// Convert it to float, silently removing double decimal points
$operands[] = (float)substr( $expr, $p, $length );
$p += $length;
$expecting = 'operator';
continue;
} elseif ( ctype_alpha( $char ) ) {
// Word
// Find the rest of it
$remaining = substr( $expr, $p );
if ( !preg_match( '/^[A-Za-z]*/', $remaining, $matches ) ) {
// This should be unreachable
throw new ExprError( 'preg_match_failure' );
}
$word = strtolower( $matches[0] );
$p += strlen( $word );
// Interpret the word
if ( !isset( self::WORDS[$word] ) ) {
throw new ExprError( 'unrecognised_word', $word );
}
$op = self::WORDS[$word];
switch ( $op ) {
// constant
case self::EXPR_EXPONENT:
if ( $expecting !== 'expression' ) {
break;
}
$operands[] = exp( 1 );
$expecting = 'operator';
continue 2;
case self::EXPR_PI:
if ( $expecting !== 'expression' ) {
throw new ExprError( 'unexpected_number' );
}
$operands[] = pi();
$expecting = 'operator';
continue 2;
// Unary operator
case self::EXPR_NOT:
case self::EXPR_SINE:
case self::EXPR_COSINE:
case self::EXPR_TANGENS:
case self::EXPR_ARCSINE:
case self::EXPR_ARCCOS:
case self::EXPR_ARCTAN:
case self::EXPR_EXP:
case self::EXPR_LN:
case self::EXPR_ABS:
case self::EXPR_FLOOR:
case self::EXPR_TRUNC:
case self::EXPR_CEIL:
case self::EXPR_SQRT:
if ( $expecting !== 'expression' ) {
throw new ExprError( 'unexpected_operator', $word );
}
$operators[] = $op;
continue 2;
}
// Binary operator, fall through
$name = $word;
} elseif ( $char2 === '<=' ) {
$name = $char2;
$op = self::EXPR_LESSEQ;
$p += 2;
} elseif ( $char2 === '>=' ) {
$name = $char2;
$op = self::EXPR_GREATEREQ;
$p += 2;
} elseif ( $char2 === '<>' || $char2 === '!=' ) {
$name = $char2;
$op = self::EXPR_NOTEQ;
$p += 2;
} elseif ( $char === '+' ) {
++$p;
if ( $expecting === 'expression' ) {
// Unary plus
$operators[] = self::EXPR_POSITIVE;
continue;
} else {
// Binary plus
$op = self::EXPR_PLUS;
}
} elseif ( $char === '-' ) {
++$p;
if ( $expecting === 'expression' ) {
// Unary minus
$operators[] = self::EXPR_NEGATIVE;
continue;
} else {
// Binary minus
$op = self::EXPR_MINUS;
}
} elseif ( $char === '*' ) {
$name = $char;
$op = self::EXPR_TIMES;
++$p;
} elseif ( $char === '/' ) {
$name = $char;
$op = self::EXPR_DIVIDE;
++$p;
} elseif ( $char === '^' ) {
$name = $char;
$op = self::EXPR_POW;
++$p;
} elseif ( $char === '(' ) {
if ( $expecting === 'operator' ) {
throw new ExprError( 'unexpected_operator', '(' );
}
$operators[] = self::EXPR_OPEN;
++$p;
continue;
} elseif ( $char === ')' ) {
$lastOp = end( $operators );
while ( $lastOp && $lastOp !== self::EXPR_OPEN ) {
$this->doOperation( $lastOp, $operands );
array_pop( $operators );
$lastOp = end( $operators );
}
if ( $lastOp ) {
array_pop( $operators );
} else {
throw new ExprError( 'unexpected_closing_bracket' );
}
$expecting = 'operator';
++$p;
continue;
} elseif ( $char === '=' ) {
$name = $char;
$op = self::EXPR_EQUALITY;
++$p;
} elseif ( $char === '<' ) {
$name = $char;
$op = self::EXPR_LESS;
++$p;
} elseif ( $char === '>' ) {
$name = $char;
$op = self::EXPR_GREATER;
++$p;
} else {
$utfExpr = Validator::cleanUp( substr( $expr, $p ) );
throw new ExprError( 'unrecognised_punctuation', mb_substr( $utfExpr, 0, 1 ) );
}
// Binary operator processing
if ( $expecting === 'expression' ) {
throw new ExprError( 'unexpected_operator', $name );
}
// Shunting yard magic
$lastOp = end( $operators );
while ( $lastOp && self::PRECEDENCE[$op] <= self::PRECEDENCE[$lastOp] ) {
$this->doOperation( $lastOp, $operands );
array_pop( $operators );
$lastOp = end( $operators );
}
$operators[] = $op;
$expecting = 'expression';
}
// Finish off the operator array
// phpcs:ignore MediaWiki.ControlStructures.AssignmentInControlStructures.AssignmentInControlStructures
while ( $op = array_pop( $operators ) ) {
if ( $op === self::EXPR_OPEN ) {
throw new ExprError( 'unclosed_bracket' );
}
$this->doOperation( $op, $operands );
}
return implode( "<br />\n", $operands );
}
/**
* @param int $op
* @param array &$stack
* @throws ExprError
*/
public function doOperation( $op, &$stack ) {
switch ( $op ) {
case self::EXPR_NEGATIVE:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = -$arg;
break;
case self::EXPR_POSITIVE:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
break;
case self::EXPR_TIMES:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = $left * $right;
break;
case self::EXPR_DIVIDE:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
if ( !$right ) {
throw new ExprError( 'division_by_zero', self::NAMES[$op] );
}
$stack[] = $left / $right;
break;
case self::EXPR_MOD:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = (int)array_pop( $stack );
$left = (int)array_pop( $stack );
if ( !$right ) {
throw new ExprError( 'division_by_zero', self::NAMES[$op] );
}
$stack[] = $left % $right;
break;
case self::EXPR_FMOD:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = (double)array_pop( $stack );
$left = (double)array_pop( $stack );
if ( !$right ) {
throw new ExprError( 'division_by_zero', self::NAMES[$op] );
}
$stack[] = fmod( $left, $right );
break;
case self::EXPR_PLUS:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = $left + $right;
break;
case self::EXPR_MINUS:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = $left - $right;
break;
case self::EXPR_AND:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = ( $left && $right ) ? 1 : 0;
break;
case self::EXPR_OR:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = ( $left || $right ) ? 1 : 0;
break;
case self::EXPR_EQUALITY:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = ( $left == $right ) ? 1 : 0;
break;
case self::EXPR_NOT:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = ( !$arg ) ? 1 : 0;
break;
case self::EXPR_ROUND:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$digits = (int)array_pop( $stack );
$value = array_pop( $stack );
$stack[] = round( $value, $digits );
break;
case self::EXPR_LESS:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = ( $left < $right ) ? 1 : 0;
break;
case self::EXPR_GREATER:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = ( $left > $right ) ? 1 : 0;
break;
case self::EXPR_LESSEQ:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = ( $left <= $right ) ? 1 : 0;
break;
case self::EXPR_GREATEREQ:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = ( $left >= $right ) ? 1 : 0;
break;
case self::EXPR_NOTEQ:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = ( $left != $right ) ? 1 : 0;
break;
case self::EXPR_EXPONENT:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$stack[] = $left * pow( 10, $right );
break;
case self::EXPR_SINE:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = sin( $arg );
break;
case self::EXPR_COSINE:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = cos( $arg );
break;
case self::EXPR_TANGENS:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = tan( $arg );
break;
case self::EXPR_ARCSINE:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
if ( $arg < -1 || $arg > 1 ) {
throw new ExprError( 'invalid_argument', self::NAMES[$op] );
}
$stack[] = asin( $arg );
break;
case self::EXPR_ARCCOS:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
if ( $arg < -1 || $arg > 1 ) {
throw new ExprError( 'invalid_argument', self::NAMES[$op] );
}
$stack[] = acos( $arg );
break;
case self::EXPR_ARCTAN:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = atan( $arg );
break;
case self::EXPR_EXP:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = exp( $arg );
break;
case self::EXPR_LN:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
if ( $arg <= 0 ) {
throw new ExprError( 'invalid_argument_ln', self::NAMES[$op] );
}
$stack[] = log( $arg );
break;
case self::EXPR_ABS:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = abs( $arg );
break;
case self::EXPR_FLOOR:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = floor( $arg );
break;
case self::EXPR_TRUNC:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = (int)$arg;
break;
case self::EXPR_CEIL:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$stack[] = ceil( $arg );
break;
case self::EXPR_POW:
if ( count( $stack ) < 2 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$right = array_pop( $stack );
$left = array_pop( $stack );
$result = pow( $left, $right );
if ( $result === false ) {
throw new ExprError( 'division_by_zero', self::NAMES[$op] );
}
$stack[] = $result;
break;
case self::EXPR_SQRT:
if ( count( $stack ) < 1 ) {
throw new ExprError( 'missing_operand', self::NAMES[$op] );
}
$arg = array_pop( $stack );
$result = sqrt( $arg );
if ( is_nan( $result ) ) {
throw new ExprError( 'not_a_number', self::NAMES[$op] );
}
$stack[] = $result;
break;
default:
// Should be impossible to reach here.
// @codeCoverageIgnoreStart
throw new ExprError( 'unknown_error' );
// @codeCoverageIgnoreEnd
}
}
}