Complex classes like TokenStream often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use TokenStream, and based on these observations, apply Extract Interface, too.
1 | <?php |
||
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) { |
|
28 | |||
29 | /** |
||
30 | * @return Token |
||
31 | */ |
||
32 | 35 | public function next() { |
|
40 | |||
41 | /** |
||
42 | * @return bool |
||
43 | */ |
||
44 | 22 | public function eof() { |
|
47 | |||
48 | /** |
||
49 | * @return Token |
||
|
|||
50 | */ |
||
51 | 22 | public function peek() { |
|
58 | |||
59 | /** |
||
60 | * @param string $msg |
||
61 | * |
||
62 | * @throws ParseException |
||
63 | */ |
||
64 | 1 | public function error($msg) { |
|
67 | |||
68 | /** |
||
69 | * @return Token |
||
70 | * @throws ParseException |
||
71 | */ |
||
72 | 35 | protected function readNext() { |
|
102 | |||
103 | 5 | protected function skipComment() { |
|
111 | |||
112 | /** |
||
113 | * @return Token |
||
114 | */ |
||
115 | 12 | protected function readDoubleQuotedString() { |
|
118 | |||
119 | /** |
||
120 | * @return Token |
||
121 | */ |
||
122 | 1 | protected function readSingleQuotedString() { |
|
125 | |||
126 | /** |
||
127 | * @return Token |
||
128 | */ |
||
129 | 10 | protected function readDoubleBracketString() { |
|
189 | |||
190 | /** |
||
191 | * @param string $end |
||
192 | * |
||
193 | * @return string |
||
194 | */ |
||
195 | 13 | protected function readEscaped($end) { |
|
218 | |||
219 | /** |
||
220 | * @return Token |
||
221 | */ |
||
222 | 10 | protected function readNumber() { |
|
238 | |||
239 | /** |
||
240 | * @return Token |
||
241 | */ |
||
242 | 15 | protected function readIdentifier() { |
|
258 | |||
259 | /** |
||
260 | * @return Token |
||
261 | */ |
||
262 | 14 | protected function readPunctuation() { |
|
265 | |||
266 | /** |
||
267 | * @param callable $predicate |
||
268 | * |
||
269 | * @return string |
||
270 | */ |
||
271 | 35 | protected function readWhile(callable $predicate) { |
|
278 | |||
279 | /** |
||
280 | * @param string $char |
||
281 | * |
||
282 | * @return bool |
||
283 | */ |
||
284 | 35 | protected function isWhitespace($char) { |
|
287 | |||
288 | /** |
||
289 | * @param string $char |
||
290 | * |
||
291 | * @return bool |
||
292 | */ |
||
293 | 23 | protected function isDigit($char) { |
|
296 | |||
297 | /** |
||
298 | * @return bool |
||
299 | */ |
||
300 | 30 | protected function isDoubleBracketString() { |
|
303 | |||
304 | /** |
||
305 | * @return bool |
||
306 | */ |
||
307 | 35 | protected function isComment() { |
|
310 | |||
311 | /** |
||
312 | * @param string $char |
||
313 | * |
||
314 | * @return bool |
||
315 | */ |
||
316 | 19 | protected function isStartIdentifierCharacter($char) { |
|
319 | |||
320 | /** |
||
321 | * @param string $char |
||
322 | * |
||
323 | * @return bool |
||
324 | */ |
||
325 | 15 | protected function isIdentifierCharacter($char) { |
|
328 | |||
329 | /** |
||
330 | * @param string $char |
||
331 | * |
||
332 | * @return bool |
||
333 | */ |
||
334 | 15 | protected function isPunctuation($char) { |
|
337 | |||
338 | /** |
||
339 | * @param string $text |
||
340 | * |
||
341 | * @return bool |
||
342 | */ |
||
343 | 15 | protected function isKeyword($text) { |
|
346 | } |
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.