XPathHelper::parseEqualityExpr() - Code Metrics - Inspection of "WiP" - s9e/TextFormatter - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Branch — TemplateParserRefactor (06d644)

by Josh

created 2018-02-15 14:09 UTC

XPathHelper::parseEqualityExpr() B

↳ Parent: XPathHelper

Complexity

Conditions	7
Paths	5

Size

Total Lines	53
Code Lines	30

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
dl	0
loc	53
rs	7.5251
c	0
b	0
f	0
cc	7
eloc	30
nc	5
nop	1

How to fix Long Method

<?php

/**
* @package   s9e\TextFormatter
* @copyright Copyright (c) 2010-2018 The s9e Authors
* @license   http://www.opensource.org/licenses/mit-license.php The MIT License
*/
namespace s9e\TextFormatter\Configurator\Helpers;

use RuntimeException;
use s9e\TextFormatter\Utils\XPath;

abstract class XPathHelper
{
	/**
	* Return the list of variables used in a given XPath expression
	*
	* @param  string $expr XPath expression
	* @return array        Alphabetically sorted list of unique variable names
	*/
	public static function getVariables($expr)
	{
		// First, remove strings' contents to prevent false-positives
		$expr = preg_replace('/(["\']).*?\\1/s', '$1$1', $expr);

		// Capture all the variable names
		preg_match_all('/\\$(\\w+)/', $expr, $matches);

		// Dedupe and sort names
		$varNames = array_unique($matches[1]);
		sort($varNames);

		return $varNames;
	}

	/**
	* Determine whether given XPath expression definitely evaluates to a number
	*
	* @param  string $expr XPath expression
	* @return bool         Whether given XPath expression definitely evaluates to a number
	*/
	public static function isExpressionNumeric($expr)
	{
		// Trim the expression and remove parentheses that are not part of a function call. PCRE
		// does not support lookbehind assertions of variable length so we have to flip the string.
		// We exclude the XPath operator "div" (flipped into "vid") to avoid false positives
		$expr = strrev(preg_replace('(\\((?!\\s*(?!vid(?!\\w))\\w))', ' ', strrev($expr)));
		$expr = str_replace(')', ' ', $expr);
		if (preg_match('(^\\s*([$@][-\\w]++|-?\\.\\d++|-?\\d++(?:\\.\\d++)?)(?>\\s*(?>[-+*]|div)\\s*(?1))++\\s*$)', $expr))
		{
			return true;
		}

		return false;
	}

	/**
	* Remove extraneous space in a given XPath expression
	*
	* @param  string $expr Original XPath expression
	* @return string       Minified XPath expression
	*/
	public static function minify($expr)
	{
		$old     = $expr;
		$strings = [];

		// Trim the surrounding whitespace then temporarily remove literal strings
		$expr = preg_replace_callback(
			'/"[^"]*"|\'[^\']*\'/',
			function ($m) use (&$strings)
			{
				$uniqid = '(' . sha1(uniqid()) . ')';
				$strings[$uniqid] = $m[0];

				return $uniqid;
			},
			trim($expr)
		);

		if (preg_match('/[\'"]/', $expr))
		{
			throw new RuntimeException("Cannot parse XPath expression '" . $old . "'");
		}

		// Normalize whitespace to a single space
		$expr = preg_replace('/\\s+/', ' ', $expr);

		// Remove the space between a non-word character and a word character
		$expr = preg_replace('/([-a-z_0-9]) ([^-a-z_0-9])/i', '$1$2', $expr);
		$expr = preg_replace('/([^-a-z_0-9]) ([-a-z_0-9])/i', '$1$2', $expr);

		// Remove the space between two non-word characters as long as they're not two -
		$expr = preg_replace('/(?!- -)([^-a-z_0-9]) ([^-a-z_0-9])/i', '$1$2', $expr);

		// Remove the space between a - and a word character, as long as there's a space before -
		$expr = preg_replace('/ - ([a-z_0-9])/i', ' -$1', $expr);

		// Remove the spaces between a number and the div operator and the next token
		$expr = preg_replace('/((?:^|[ \\(])\\d+) div ?/', '$1div', $expr);

		// Remove the space between the div operator the next token
		$expr = preg_replace('/([^-a-z_0-9]div) (?=[$0-9@])/', '$1', $expr);

		// Restore the literals
		$expr = strtr($expr, $strings);

		return $expr;
	}

	/**
	* Parse an XPath expression that is composed entirely of equality tests between a variable part
	* and a constant part
	*
	* @param  string      $expr
	* @return array|false
	*/
	public static function parseEqualityExpr($expr)
	{
		// Match an equality between a variable and a literal or the concatenation of strings
		$eq = '(?<equality>'
		    . '(?<key>@[-\\w]+|\\$\\w+|\\.)'
		    . '(?<operator>\\s*=\\s*)'
		    . '(?:'
		    . '(?<literal>(?<string>"[^"]*"|\'[^\']*\')|0|[1-9][0-9]*)'
		    . '|'
		    . '(?<concat>concat\\(\\s*(?&string)\\s*(?:,\\s*(?&string)\\s*)+\\))'
		    . ')'
		    . '|'
		    . '(?:(?<literal>(?&literal))|(?<concat>(?&concat)))(?&operator)(?<key>(?&key))'
		    . ')';

		// Match a string that is entirely composed of equality checks separated with "or"
		$regexp = '(^(?J)\\s*' . $eq . '\\s*(?:or\\s*(?&equality)\\s*)*$)';

		if (!preg_match($regexp, $expr))
		{
			return false;
		}

		preg_match_all("((?J)$eq)", $expr, $matches, PREG_SET_ORDER);

		$map = [];
		foreach ($matches as $m)
		{
			$key = $m['key'];
			if (!empty($m['concat']))
			{
				preg_match_all('(\'[^\']*\'|"[^"]*")', $m['concat'], $strings);

				$value = '';
				foreach ($strings[0] as $string)
				{
					$value .= substr($string, 1, -1);
				}
			}
			else
			{
				$value = $m['literal'];
				if ($value[0] === "'" || $value[0] === '"')
				{
					$value = substr($value, 1, -1);
				}
			}

			$map[$key][] = $value;
		}

		return $map;
	}
}

1			<?php
2
3			/**
4			* @package s9e\TextFormatter
5			* @copyright Copyright (c) 2010-2018 The s9e Authors
6			* @license http://www.opensource.org/licenses/mit-license.php The MIT License
7			*/
8			namespace s9e\TextFormatter\Configurator\Helpers;
9
10			use RuntimeException;
11			use s9e\TextFormatter\Utils\XPath;
12
13			abstract class XPathHelper
14			{
15			/**
16			* Return the list of variables used in a given XPath expression
17			*
18			* @param string $expr XPath expression
19			* @return array Alphabetically sorted list of unique variable names
20			*/
21			public static function getVariables($expr)
22			{
23			// First, remove strings' contents to prevent false-positives
24			$expr = preg_replace('/(["\']).*?\\1/s', '$1$1', $expr);
25
26			// Capture all the variable names
27			preg_match_all('/\\$(\\w+)/', $expr, $matches);
28
29			// Dedupe and sort names
30			$varNames = array_unique($matches[1]);
31			sort($varNames);
32
33			return $varNames;
34			}
35
36			/**
37			* Determine whether given XPath expression definitely evaluates to a number
38			*
39			* @param string $expr XPath expression
40			* @return bool Whether given XPath expression definitely evaluates to a number
41			*/
42			public static function isExpressionNumeric($expr)
43			{
44			// Trim the expression and remove parentheses that are not part of a function call. PCRE
45			// does not support lookbehind assertions of variable length so we have to flip the string.
46			// We exclude the XPath operator "div" (flipped into "vid") to avoid false positives
47			$expr = strrev(preg_replace('(\\((?!\\s*(?!vid(?!\\w))\\w))', ' ', strrev($expr)));
48			$expr = str_replace(')', ' ', $expr);
49			if (preg_match('(^\\s([$@][-\\w]++\|-?\\.\\d++\|-?\\d++(?:\\.\\d++)?)(?>\\s(?>[-+]\|div)\\s(?1))++\\s*$)', $expr))
50			{
51			return true;
52			}
53
54			return false;
55			}
56
57			/**
58			* Remove extraneous space in a given XPath expression
59			*
60			* @param string $expr Original XPath expression
61			* @return string Minified XPath expression
62			*/
63			public static function minify($expr)
64			{
65			$old = $expr;
66			$strings = [];
67
68			// Trim the surrounding whitespace then temporarily remove literal strings
69			$expr = preg_replace_callback(
70			'/"[^"]"\|\'[^\']\'/',
71			function ($m) use (&$strings)
72			{
73			$uniqid = '(' . sha1(uniqid()) . ')';
74			$strings[$uniqid] = $m[0];
75
76			return $uniqid;
77			},
78			trim($expr)
79			);
80
81			if (preg_match('/[\'"]/', $expr))
82			{
83			throw new RuntimeException("Cannot parse XPath expression '" . $old . "'");
84			}
85
86			// Normalize whitespace to a single space
87			$expr = preg_replace('/\\s+/', ' ', $expr);
88
89			// Remove the space between a non-word character and a word character
90			$expr = preg_replace('/([-a-z_0-9]) ([^-a-z_0-9])/i', '$1$2', $expr);
91			$expr = preg_replace('/([^-a-z_0-9]) ([-a-z_0-9])/i', '$1$2', $expr);
92
93			// Remove the space between two non-word characters as long as they're not two -
94			$expr = preg_replace('/(?!- -)([^-a-z_0-9]) ([^-a-z_0-9])/i', '$1$2', $expr);
95
96			// Remove the space between a - and a word character, as long as there's a space before -
97			$expr = preg_replace('/ - ([a-z_0-9])/i', ' -$1', $expr);
98
99			// Remove the spaces between a number and the div operator and the next token
100			$expr = preg_replace('/((?:^\|[ \\(])\\d+) div ?/', '$1div', $expr);
101
102			// Remove the space between the div operator the next token
103			$expr = preg_replace('/([^-a-z_0-9]div) (?=[$0-9@])/', '$1', $expr);
104
105			// Restore the literals
106			$expr = strtr($expr, $strings);
107
108			return $expr;
109			}
110
111			/**
112			* Parse an XPath expression that is composed entirely of equality tests between a variable part
113			* and a constant part
114			*
115			* @param string $expr
116			* @return array\|false
117			*/
118			public static function parseEqualityExpr($expr)
119			{
120			// Match an equality between a variable and a literal or the concatenation of strings
121			$eq = '(?<equality>'
122			. '(?<key>@[-\\w]+\|\\$\\w+\|\\.)'
123			. '(?<operator>\\s=\\s)'
124			. '(?:'
125			. '(?<literal>(?<string>"[^"]"\|\'[^\']\')\|0\|[1-9][0-9]*)'
126			. '\|'
127			. '(?<concat>concat\\(\\s(?&string)\\s(?:,\\s(?&string)\\s)+\\))'
128			. ')'
129			. '\|'
130			. '(?:(?<literal>(?&literal))\|(?<concat>(?&concat)))(?&operator)(?<key>(?&key))'
131			. ')';
132
133			// Match a string that is entirely composed of equality checks separated with "or"
134			$regexp = '(^(?J)\\s' . $eq . '\\s(?:or\\s(?&equality)\\s)*$)';
135
136			if (!preg_match($regexp, $expr))
137			{
138			return false;
139			}
140
141			preg_match_all("((?J)$eq)", $expr, $matches, PREG_SET_ORDER);
142
143			$map = [];
144			foreach ($matches as $m)
145			{
146			$key = $m['key'];
147			if (!empty($m['concat']))
148			{
149			preg_match_all('(\'[^\']\'\|"[^"]")', $m['concat'], $strings);
150
151			$value = '';
152			foreach ($strings[0] as $string)
153			{
154			$value .= substr($string, 1, -1);
155			}
156			}
157			else
158			{
159			$value = $m['literal'];
160			if ($value[0] === "'" \|\| $value[0] === '"')
161			{
162			$value = substr($value, 1, -1);
163			}
164			}
165
166			$map[$key][] = $value;
167			}
168
169			return $map;
170			}
171			}

s9e / TextFormatter

Branch — TemplateParserRefactor (06d644)

XPathHelper::parseEqualityExpr() B

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How to fix Long Method

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