code-snippets / php / class-validator.php

class-validator.php in Code Snippets 2.14.1, at php/class-validator.php

248 lines 6.5 KB

Raw Download Zip

1	<?php
2
3	/**
4	* Validates code prior to execution.
5	*
6	* @package Code_Snippets
7	*/
8	class Code_Snippets_Validator {
9
10	/**
11	* @var string
12	*/
13	private $code;
14
15	/**
16	* @var array
17	*/
18	private $tokens;
19
20	/**
21	* The index of the token currently being examined.
22	*
23	* @var int
24	*/
25	private $current;
26
27	/**
28	* The total number of tokens.
29	*
30	* @var int
31	*/
32	private $length;
33
34	/**
35	* Array to keep track of the various function, class and interface identifiers which have been defined.
36	*
37	* @var array
38	*/
39	private $defined_identifiers = array();
40
41	/**
42	* Exclude certain tokens from being checked.
43	*
44	* @var array
45	*/
46	private $exceptions = array();
47
48	/**
49	* Class constructor.
50	*
51	* @param string $code Snippet code for parsing.
52	*/
53	public function __construct( $code ) {
54	$this->code = $code;
55	$this->tokens = token_get_all( "<?php\n" . $this->code );
56	$this->length = count( $this->tokens );
57	$this->current = 0;
58	}
59
60	/**
61	* Determine whether the parser has reached the end of the list of tokens.
62	*
63	* @return bool
64	*/
65	private function end() {
66	return $this->current === $this->length;
67	}
68
69	/**
70	* Retrieve the next token without moving the pointer
71	*
72	* @return string\|array\|null The current token if the list has not been expended, null otherwise.
73	*/
74	private function peek() {
75	return $this->end() ? null : $this->tokens[ $this->current ];
76	}
77
78	/**
79	* Move the pointer to the next token, if there is one
80	*
81	* If the first argument is provided, only move the pointer if the tokens match
82	*
83	* @return bool Whether the pointer was advanced.
84	*/
85	private function next() {
86	if ( $this->end() ) {
87	return false;
88	}
89
90	$this->current++;
91	return true;
92	}
93
94	/**
95	* Check whether a particular identifier has been used previously.
96	*
97	* @param string $type Which type of identifier this is. Supports T_FUNCTION, T_CLASS and T_INTERFACE.
98	* @param string $identifier The name of the identifier itself.
99	*
100	* @return bool true if the identifier is not unique.
101	*/
102	private function check_duplicate_identifier( $type, $identifier ) {
103
104	if ( ! isset( $this->defined_identifiers[ $type ] ) ) {
105	switch ( $type ) {
106	case T_FUNCTION:
107	$defined_functions = get_defined_functions();
108	$this->defined_identifiers[ T_FUNCTION ] = array_merge( $defined_functions['internal'], $defined_functions['user'] );
109	break;
110
111	case T_CLASS:
112	$this->defined_identifiers[ T_CLASS ] = get_declared_classes();
113	break;
114
115	case T_INTERFACE:
116	$this->defined_identifiers[ T_INTERFACE ] = get_declared_interfaces();
117	break;
118
119	default:
120	return false;
121	}
122	}
123
124	$duplicate = in_array( $identifier, $this->defined_identifiers[ $type ], true );
125	array_unshift( $this->defined_identifiers[ $type ], $identifier );
126	return $duplicate && ! ( isset( $this->exceptions[ $type ] ) && in_array( $identifier, $this->exceptions[ $type ], true ) );
127	}
128
129	/**
130	* Validate the given PHP code and return the result.
131	* @return array\|bool Array containing message if an error was encountered, false if validation was successful.
132	*/
133	public function validate() {
134
135	while ( ! $this->end() ) {
136	$token = $this->peek();
137	$this->next();
138
139	if ( ! is_array( $token ) ) {
140	continue;
141	}
142
143	// if this is a function or class exists check, then allow this function or class to be defined
144	if ( T_STRING === $token[0] && 'function_exists' === $token[1] \|\| 'class_exists' === $token[1] ) {
145	$type = 'function_exists' === $token[1] ? T_FUNCTION : T_CLASS;
146
147	// eat tokens until we find the function or class name
148	while ( ! $this->end() && T_CONSTANT_ENCAPSED_STRING !== $token[0] ) {
149	$token = $this->peek();
150	$this->next();
151	}
152
153	// add the identifier to the list of exceptions
154	$this->exceptions[ $type ] = isset( $this->exceptions[ $type ] ) ? $this->exceptions[ $type ] : array();
155	$this->exceptions[ $type ][] = trim( $token[1], '\'"' );
156	continue;
157	}
158
159	// only look for class and function declaration tokens
160	if ( T_CLASS !== $token[0] && T_FUNCTION !== $token[0] ) {
161	continue;
162	}
163
164	$structure_type = $token[0];
165
166	// continue eating tokens until we find the name of the class or function
167	while ( ! $this->end() && T_STRING !== $token[0] &&
168	( T_FUNCTION !== $structure_type \|\| '(' !== $token ) && ( T_CLASS !== $structure_type \|\| '{' !== $token ) ) {
169	$token = $this->peek();
170	$this->next();
171	}
172
173	// if we've eaten all of the tokens without discovering a name, then there must be a syntax error, so return appropriately
174	if ( $this->end() ) {
175	return array(
176	'message' => __( 'Parse error: syntax error, unexpected end of snippet.', 'code-snippets' ),
177	'line' => $token[2],
178	);
179	}
180
181	// if the function or class is anonymous, with no name, then no need to check
182	if ( ! ( T_FUNCTION === $structure_type && '(' === $token ) && ! ( T_CLASS === $structure_type && '{' === $token ) ) {
183
184	// check whether the name has already been defined
185	if ( $this->check_duplicate_identifier( $structure_type, $token[1] ) ) {
186	switch ( $structure_type ) {
187	case T_FUNCTION:
188	/* translators: %s: PHP function name */
189	$message = __( 'Cannot redeclare function %s.', 'code-snippets' );
190	break;
191	case T_CLASS:
192	/* translators: %s: PHP class name */
193	$message = __( 'Cannot redeclare class %s.', 'code-snippets' );
194	break;
195	case T_INTERFACE:
196	/* translators: %s: PHP interface name */
197	$message = __( 'Cannot redeclare interface %s.', 'code-snippets' );
198	break;
199	default:
200	/* translators: %s: PHP identifier name*/
201	$message = __( 'Cannot redeclare %s.', 'code-snippets' );
202	}
203
204	return array(
205	'message' => sprintf( $message, $token[1] ),
206	'line' => $token[2],
207	);
208	}
209	}
210
211	// if we have entered into a class, eat tokens until we find the closing brace
212	if ( T_CLASS !== $structure_type ) {
213	continue;
214	}
215
216	// find the opening brace for the class
217	while ( ! $this->end() && '{' !== $token ) {
218	$token = $this->peek();
219	$this->next();
220	}
221
222	// continue traversing the class tokens until we have found the class closing brace
223	$depth = 1;
224	while ( ! $this->end() && $depth > 0 ) {
225	$token = $this->peek();
226
227	if ( '{' === $token ) {
228	$depth++;
229	} elseif ( '}' === $token ) {
230	$depth--;
231	}
232
233	$this->next();
234	}
235
236	// if we did not make it out of the class, then there's a problem
237	if ( $depth > 0 ) {
238	return array(
239	'message' => __( 'Parse error: syntax error, unexpected end of snippet', 'code-snippets' ),
240	'line' => $token[2],
241	);
242	}
243	}
244
245	return false;
246	}
247	}
248