TokenStream::readEscaped() - Code Metrics - Inspection of "Parse nested strings correctly, fixes #4" - koesie10/LuaSerializer - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Push — master ( b8c5dd...52423a )

by Koen

created 2016-09-22 07:06 UTC

TokenStream::readEscaped() B

↳ Parent: TokenStream

Complexity

Conditions	5
Paths	5

Size

Total Lines	23
Code Lines	18

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	13
CRAP Score	5.5359

Importance

Changes

Metric	Value
dl	0
loc	23
c	0
b	0
f	0
ccs	13
cts	18
cp	0.7221
rs	8.5906
nc	5
cc	5
eloc	18
nop	1
crap	5.5359

<?php

namespace Vlaswinkel\Lua;

/**
 * Class TokenStream
 *
 * @see     http://lisperator.net/pltut/parser/token-stream
 *
 * @author  Koen Vlaswinkel <[email protected]>
 * @package Vlaswinkel\Lua
 */
class TokenStream {
    private $current = null;
    /**
     * @var InputStream
     */
    private $input;

    /**
     * TokenStream constructor.
     *
     * @param InputStream $input
     */
    public function __construct(InputStream $input) {
        $this->input = $input;
    }

    /**
     * @return Token
     */
    public function next() {
        $token         = $this->current;
        $this->current = null;
        if ($token) {
            return $token;
        }
        return $this->readNext();
    }

    /**
     * @return bool
     */
    public function eof() {
        return $this->peek() == null;
    }

    /**
     * @return Token

     */
    public function peek() {
        if ($this->current) {
            return $this->current;
        }
        $this->current = $this->readNext();
        return $this->current;
    }

    /**
     * @param string $msg
     *
     * @throws ParseException
     */
    public function error($msg) {
        $this->input->error($msg);
    }

    /**
     * @return Token

     * @throws ParseException
     */
    protected function readNext() {
        $this->readWhile([$this, 'isWhitespace']);
        if ($this->input->eof()) {
            return null;
        }
        $char = $this->input->peek();
        if ($this->isComment()) {
            $this->skipComment();
            return $this->readNext();
        }
        if ($char == '"') {
            return $this->readDoubleQuotedString();
        }
        if ($char == '\'') {
            return $this->readSingleQuotedString();
        }
        if ($this->isDoubleBracketString()) {
            return $this->readDoubleBracketString();
        }
        if ($this->isDigit($char)) {
            return $this->readNumber();
        }
        if ($this->isStartIdentifierCharacter($char)) {
            return $this->readIdentifier();
        }
        if ($this->isPunctuation($char)) {
            return $this->readPunctuation();
        }
        $this->input->error('Cannot handle character: ' . $char . ' (ord: ' . ord($char) . ')');
    }

    protected function skipComment() {
        $this->readWhile(
            function ($char) {
                return $char != "\n";
            }
        );
        $this->input->next();
    }

    /**
     * @return Token
     */
    protected function readDoubleQuotedString() {
        return new Token(Token::TYPE_STRING, $this->readEscaped('"'));
    }

    /**
     * @return Token
     */
    protected function readSingleQuotedString() {
        return new Token(Token::TYPE_STRING, $this->readEscaped('\''));
    }

    /**
     * @return Token
     */
    protected function readDoubleBracketString() {
        // we cannot use readEscaped because it only supports a single char as $end
        $escaped                  = false;
        $str                      = "";
        $startNumberOfEqualsSigns = 0;
        // skip both
        $this->input->next();
        while ($this->input->peek() == '=') {
            $startNumberOfEqualsSigns++;
            $this->input->next();
        }
        if ($this->input->peek() != '[') {
            $this->error('Unexpected character ' . $this->input->peek() . ', expected [');
        }
        $this->input->next();
        while (!$this->input->eof()) {
            $char = $this->input->next();
            if ($escaped) {
                $str .= $char;
                $escaped = false;
            } else {
                if ($char == "\\") {
                    $escaped = true;
                } else {
                    if ($char == ']') { // we might have reached the end
                        if ($startNumberOfEqualsSigns != 0) {
                            if ($this->input->peek() == '=') {
                                $endNumberOfEqualsSigns = 0;
                                while ($this->input->peek() == '=') {
                                    $endNumberOfEqualsSigns++;
                                    $this->input->next();
                                }

                                // we have an equal number of equal signs
                                if ($endNumberOfEqualsSigns == $startNumberOfEqualsSigns) {
                                    if ($this->input->peek() != ']') {
                                        $this->error('Unexpected character ' . $this->input->peek() . ', expected [');
                                    }
                                    $this->input->next();
                                    break;
                                } else {
                                    $str .= $char . str_repeat('=', $endNumberOfEqualsSigns);
                                }
                            } else {
                                $str .= $char;
                            }
                        } else {
                            if ($this->input->peek() == ']') {
                                $this->input->next();
                                break;
                            }
                        }
                    } else {
                        $str .= $char;
                    }
                }
            }
        }
        return new Token(Token::TYPE_STRING, $str);
    }

    /**
     * @param string $end
     *
     * @return string
     */
    protected function readEscaped($end) {
        $escaped = false;
        $str     = "";
        $this->input->next();
        while (!$this->input->eof()) {
            $char = $this->input->next();
            if ($escaped) {
                $str .= $char;
                $escaped = false;
            } else {
                if ($char == "\\") {
                    $escaped = true;
                } else {
                    if ($char == $end) {
                        break;
                    } else {
                        $str .= $char;
                    }
                }
            }
        }
        return $str;
    }

    /**
     * @return Token
     */
    protected function readNumber() {
        $hasDot = false;
        $number = $this->readWhile(
            function ($char) use (&$hasDot) {
                if ($char == '.') {
                    if ($hasDot) {
                        return false;
                    }
                    $hasDot = true;
                    return true;
                }
                return $this->isDigit($char);
            }
        );
        return new Token(Token::TYPE_NUMBER, $hasDot ? floatval($number) : intval($number));
    }

    /**
     * @return Token
     */
    protected function readIdentifier() {
        $first      = false;
        $identifier = $this->readWhile(
            function ($char) use (&$first) {
                if ($first) {
                    $first = false;
                    return $this->isStartIdentifierCharacter($char);
                }
                return $this->isIdentifierCharacter($char);
            }
        );
        if ($this->isKeyword($identifier)) {
            return new Token(Token::TYPE_KEYWORD, $identifier);
        }
        return new Token(Token::TYPE_IDENTIFIER, $identifier);
    }

    /**
     * @return Token
     */
    protected function readPunctuation() {
        return new Token(Token::TYPE_PUNCTUATION, $this->input->next());
    }

    /**
     * @param callable $predicate
     *
     * @return string
     */
    protected function readWhile(callable $predicate) {
        $str = "";
        while (!$this->input->eof() && call_user_func($predicate, $this->input->peek())) {
            $str .= $this->input->next();
        }
        return $str;
    }

    /**
     * @param string $char
     *
     * @return bool
     */
    protected function isWhitespace($char) {
        return strpos(" \t\n\r", $char) !== false;
    }

    /**
     * @param string $char
     *
     * @return bool
     */
    protected function isDigit($char) {
        return is_numeric($char);
    }

    /**
     * @return bool
     */
    protected function isDoubleBracketString() {
        return $this->input->peek() == '[' && !$this->input->eof(1) && ($this->input->peek(1) == '[' || $this->input->peek(1) == '=');
    }

    /**
     * @return bool
     */
    protected function isComment() {
        return $this->input->peek() == '-' && !$this->input->eof(1) && $this->input->peek(1) == '-';
    }

    /**
     * @param string $char
     *
     * @return bool
     */
    protected function isStartIdentifierCharacter($char) {
        return preg_match('/[a-zA-Z_]/', $char) === 1;
    }

    /**
     * @param string $char
     *
     * @return bool
     */
    protected function isIdentifierCharacter($char) {
        return preg_match('/[a-zA-Z0-9_]/', $char) === 1;
    }

    /**
     * @param string $char
     *
     * @return bool
     */
    protected function isPunctuation($char) {
        return strpos(",{}=[]", $char) !== false;
    }

    /**
     * @param string $text
     *
     * @return bool
     */
    protected function isKeyword($text) {
        return in_array($text, Lua::$luaKeywords);
    }
}

1		<?php
2
3		namespace Vlaswinkel\Lua;
4
5		/**
6		* Class TokenStream
7		*
8		* @see http://lisperator.net/pltut/parser/token-stream
9		*
10		* @author Koen Vlaswinkel <[email protected]>
11		* @package Vlaswinkel\Lua
12		*/
13		class TokenStream {
14		private $current = null;
15		/**
16		* @var InputStream
17		*/
18		private $input;
19
20		/**
21		* TokenStream constructor.
22		*
23		* @param InputStream $input
24		*/
25	35	public function __construct(InputStream $input) {
26	35	$this->input = $input;
27	35	}
28
29		/**
30		* @return Token
31		*/
32	35	public function next() {
33	35	$token = $this->current;
34	35	$this->current = null;
35	35	if ($token) {
36	22	return $token;
37		}
38	13	return $this->readNext();
39		}
40
41		/**
42		* @return bool
43		*/
44	22	public function eof() {
45	22	return $this->peek() == null;
46		}
47
48		/**
49		* @return Token
		0 ignored issues – show Documentation introduced 2015-12-22 12:03 UTC by Report Bug Copy Issue Report Should the return type not be `Token\|null`? This check compares the return type specified in the `@return` annotation of a function or method doc comment with the types returned by the function and raises an issue if they mismatch. Loading history...
50		*/
51	22	public function peek() {
52	22	if ($this->current) {
53	22	return $this->current;
54		}
55	22	$this->current = $this->readNext();
56	22	return $this->current;
57		}
58
59		/**
60		* @param string $msg
61		*
62		* @throws ParseException
63		*/
64	1	public function error($msg) {
65	1	$this->input->error($msg);
66		}
67
68		/**
69		* @return Token
		0 ignored issues – show Documentation introduced 2015-12-22 12:03 UTC by Report Bug Copy Issue Report Should the return type not be `Token\|null`? This check compares the return type specified in the `@return` annotation of a function or method doc comment with the types returned by the function and raises an issue if they mismatch. Loading history...
70		* @throws ParseException
71		*/
72	35	protected function readNext() {
73	35	$this->readWhile([$this, 'isWhitespace']);
74	35	if ($this->input->eof()) {
75	19	return null;
76		}
77	35	$char = $this->input->peek();
78	35	if ($this->isComment()) {
79	5	$this->skipComment();
80	5	return $this->readNext();
81		}
82	35	if ($char == '"') {
83	12	return $this->readDoubleQuotedString();
84		}
85	31	if ($char == '\'') {
86	1	return $this->readSingleQuotedString();
87		}
88	30	if ($this->isDoubleBracketString()) {
89	10	return $this->readDoubleBracketString();
90		}
91	23	if ($this->isDigit($char)) {
92	10	return $this->readNumber();
93		}
94	19	if ($this->isStartIdentifierCharacter($char)) {
95	15	return $this->readIdentifier();
96		}
97	15	if ($this->isPunctuation($char)) {
98	14	return $this->readPunctuation();
99		}
100	1	$this->input->error('Cannot handle character: ' . $char . ' (ord: ' . ord($char) . ')');
101		}
102
103	5	protected function skipComment() {
104	5	$this->readWhile(
105		function ($char) {
106	5	return $char != "\n";
107		}
108	5	);
109	5	$this->input->next();
110	5	}
111
112		/**
113		* @return Token
114		*/
115	12	protected function readDoubleQuotedString() {
116	12	return new Token(Token::TYPE_STRING, $this->readEscaped('"'));
117		}
118
119		/**
120		* @return Token
121		*/
122	1	protected function readSingleQuotedString() {
123	1	return new Token(Token::TYPE_STRING, $this->readEscaped('\''));
124		}
125
126		/**
127		* @return Token
128		*/
129	10	protected function readDoubleBracketString() {
130		// we cannot use readEscaped because it only supports a single char as $end
131	10	$escaped = false;
132	10	$str = "";
133	10	$startNumberOfEqualsSigns = 0;
134		// skip both
135	10	$this->input->next();
136	10	while ($this->input->peek() == '=') {
137	5	$startNumberOfEqualsSigns++;
138	5	$this->input->next();
139	5	}
140	10	if ($this->input->peek() != '[') {
141		$this->error('Unexpected character ' . $this->input->peek() . ', expected [');
142		}
143	10	$this->input->next();
144	10	while (!$this->input->eof()) {
145	10	$char = $this->input->next();
146	10	if ($escaped) {
147		$str .= $char;
148		$escaped = false;
149		} else {
150	10	if ($char == "\\") {
151		$escaped = true;
152		} else {
153	10	if ($char == ']') { // we might have reached the end
154	10	if ($startNumberOfEqualsSigns != 0) {
155	5	if ($this->input->peek() == '=') {
156	4	$endNumberOfEqualsSigns = 0;
157	4	while ($this->input->peek() == '=') {
158	4	$endNumberOfEqualsSigns++;
159	4	$this->input->next();
160	4	}
161
162		// we have an equal number of equal signs
163	4	if ($endNumberOfEqualsSigns == $startNumberOfEqualsSigns) {
164	4	if ($this->input->peek() != ']') {
165		$this->error('Unexpected character ' . $this->input->peek() . ', expected [');
166		}
167	4	$this->input->next();
168	4	break;
169		} else {
170	1	$str .= $char . str_repeat('=', $endNumberOfEqualsSigns);
171		}
172	1	} else {
173	3	$str .= $char;
174		}
175	3	} else {
176	5	if ($this->input->peek() == ']') {
177	5	$this->input->next();
178	5	break;
179		}
180		}
181	3	} else {
182	10	$str .= $char;
183		}
184		}
185		}
186	10	}
187	9	return new Token(Token::TYPE_STRING, $str);
188		}
189
190		/**
191		* @param string $end
192		*
193		* @return string
194		*/
195	13	protected function readEscaped($end) {
196	13	$escaped = false;
197	13	$str = "";
198	13	$this->input->next();
199	13	while (!$this->input->eof()) {
200	13	$char = $this->input->next();
201	13	if ($escaped) {
202		$str .= $char;
203		$escaped = false;
204		} else {
205	13	if ($char == "\\") {
206		$escaped = true;
207		} else {
208	13	if ($char == $end) {
209	13	break;
210		} else {
211	13	$str .= $char;
212		}
213		}
214		}
215	13	}
216	13	return $str;
217		}
218
219		/**
220		* @return Token
221		*/
222	10	protected function readNumber() {
223	10	$hasDot = false;
224	10	$number = $this->readWhile(
225		function ($char) use (&$hasDot) {
226	10	if ($char == '.') {
227	1	if ($hasDot) {
228		return false;
229		}
230	1	$hasDot = true;
231	1	return true;
232		}
233	10	return $this->isDigit($char);
234		}
235	10	);
236	10	return new Token(Token::TYPE_NUMBER, $hasDot ? floatval($number) : intval($number));
237		}
238
239		/**
240		* @return Token
241		*/
242	15	protected function readIdentifier() {
243	15	$first = false;
244	15	$identifier = $this->readWhile(
245	15	function ($char) use (&$first) {
246	15	if ($first) {
247		$first = false;
248		return $this->isStartIdentifierCharacter($char);
249		}
250	15	return $this->isIdentifierCharacter($char);
251		}
252	15	);
253	15	if ($this->isKeyword($identifier)) {
254	5	return new Token(Token::TYPE_KEYWORD, $identifier);
255		}
256	12	return new Token(Token::TYPE_IDENTIFIER, $identifier);
257		}
258
259		/**
260		* @return Token
261		*/
262	14	protected function readPunctuation() {
263	14	return new Token(Token::TYPE_PUNCTUATION, $this->input->next());
264		}
265
266		/**
267		* @param callable $predicate
268		*
269		* @return string
270		*/
271	35	protected function readWhile(callable $predicate) {
272	35	$str = "";
273	35	while (!$this->input->eof() && call_user_func($predicate, $this->input->peek())) {
274	19	$str .= $this->input->next();
275	19	}
276	35	return $str;
277		}
278
279		/**
280		* @param string $char
281		*
282		* @return bool
283		*/
284	35	protected function isWhitespace($char) {
285	35	return strpos(" \t\n\r", $char) !== false;
286		}
287
288		/**
289		* @param string $char
290		*
291		* @return bool
292		*/
293	23	protected function isDigit($char) {
294	23	return is_numeric($char);
295		}
296
297		/**
298		* @return bool
299		*/
300	30	protected function isDoubleBracketString() {
301	30	return $this->input->peek() == '[' && !$this->input->eof(1) && ($this->input->peek(1) == '[' \|\| $this->input->peek(1) == '=');
302		}
303
304		/**
305		* @return bool
306		*/
307	35	protected function isComment() {
308	35	return $this->input->peek() == '-' && !$this->input->eof(1) && $this->input->peek(1) == '-';
309		}
310
311		/**
312		* @param string $char
313		*
314		* @return bool
315		*/
316	19	protected function isStartIdentifierCharacter($char) {
317	19	return preg_match('/[a-zA-Z_]/', $char) === 1;
318		}
319
320		/**
321		* @param string $char
322		*
323		* @return bool
324		*/
325	15	protected function isIdentifierCharacter($char) {
326	15	return preg_match('/[a-zA-Z0-9_]/', $char) === 1;
327		}
328
329		/**
330		* @param string $char
331		*
332		* @return bool
333		*/
334	15	protected function isPunctuation($char) {
335	15	return strpos(",{}=[]", $char) !== false;
336		}
337
338		/**
339		* @param string $text
340		*
341		* @return bool
342		*/
343	15	protected function isKeyword($text) {
344	15	return in_array($text, Lua::$luaKeywords);
345		}
346		}

koesie10 / LuaSerializer

Push — master ( b8c5dd...52423a )

TokenStream::readEscaped() B

Complexity

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Duplication

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