1 
2 // Copyright 2021 the V8 project authors. All rights reserved.
3 // Use of this source code is governed by a BSD-style license that can be
4 // found in the LICENSE file.
5 
6 #ifndef INCLUDE_V8_REGEXP_H_
7 #define INCLUDE_V8_REGEXP_H_
8 
9 #include "v8-local-handle.h"  // NOLINT(build/include_directory)
10 #include "v8-object.h"        // NOLINT(build/include_directory)
11 #include "v8config.h"         // NOLINT(build/include_directory)
12 
13 namespace v8 {
14 
15 class Context;
16 
17 /**
18  * An instance of the built-in RegExp constructor (ECMA-262, 15.10).
19  */
20 class V8_EXPORT RegExp : public Object {
21  public:
22   /**
23    * Regular expression flag bits. They can be or'ed to enable a set
24    * of flags.
25    * The kLinear value ('l') is experimental and can only be used with
26    * --enable-experimental-regexp-engine.  RegExps with kLinear flag are
27    *  guaranteed to be executed in asymptotic linear time wrt. the length of
28    *  the subject string.
29    */
30   enum Flags {
31     kNone = 0,
32     kGlobal = 1 << 0,
33     kIgnoreCase = 1 << 1,
34     kMultiline = 1 << 2,
35     kSticky = 1 << 3,
36     kUnicode = 1 << 4,
37     kDotAll = 1 << 5,
38     kLinear = 1 << 6,
39     kHasIndices = 1 << 7,
40   };
41 
42   static constexpr int kFlagCount = 8;
43 
44   /**
45    * Creates a regular expression from the given pattern string and
46    * the flags bit field. May throw a JavaScript exception as
47    * described in ECMA-262, 15.10.4.1.
48    *
49    * For example,
50    *   RegExp::New(v8::String::New("foo"),
51    *               static_cast<RegExp::Flags>(kGlobal | kMultiline))
52    * is equivalent to evaluating "/foo/gm".
53    */
54   static V8_WARN_UNUSED_RESULT MaybeLocal<RegExp> New(Local<Context> context,
55                                                       Local<String> pattern,
56                                                       Flags flags);
57 
58   /**
59    * Like New, but additionally specifies a backtrack limit. If the number of
60    * backtracks done in one Exec call hits the limit, a match failure is
61    * immediately returned.
62    */
63   static V8_WARN_UNUSED_RESULT MaybeLocal<RegExp> NewWithBacktrackLimit(
64       Local<Context> context, Local<String> pattern, Flags flags,
65       uint32_t backtrack_limit);
66 
67   /**
68    * Executes the current RegExp instance on the given subject string.
69    * Equivalent to RegExp.prototype.exec as described in
70    *
71    *   https://tc39.es/ecma262/#sec-regexp.prototype.exec
72    *
73    * On success, an Array containing the matched strings is returned. On
74    * failure, returns Null.
75    *
76    * Note: modifies global context state, accessible e.g. through RegExp.input.
77    */
78   V8_WARN_UNUSED_RESULT MaybeLocal<Object> Exec(Local<Context> context,
79                                                 Local<String> subject);
80 
81   /**
82    * Returns the value of the source property: a string representing
83    * the regular expression.
84    */
85   Local<String> GetSource() const;
86 
87   /**
88    * Returns the flags bit field.
89    */
90   Flags GetFlags() const;
91 
Cast(Value * value)92   V8_INLINE static RegExp* Cast(Value* value) {
93 #ifdef V8_ENABLE_CHECKS
94     CheckCast(value);
95 #endif
96     return static_cast<RegExp*>(value);
97   }
98 
99  private:
100   static void CheckCast(Value* obj);
101 };
102 
103 }  // namespace v8
104 
105 #endif  // INCLUDE_V8_REGEXP_H_
106