1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
|
//===----------------------------------------------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2021-2022 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
//
//===----------------------------------------------------------------------===//
// The version number for the regex. This gets emitted as an argument to the
// Regex(_regexString:version:) initializer and should be bumped if the format
// of the regex string needs to be changed in such a that requires the runtime
// to updated.
public let currentRegexLiteralFormatVersion = 1
@_spi(CompilerInterface)
public struct CompilerLexError: Error {
var underlyingLocation: UnsafeSourceLocation
public var message: String
public var location: UnsafeRawPointer { return underlyingLocation.ptr }
public var completelyErroneous: Bool
init(
message: String, location: UnsafeRawPointer, completelyErroneous: Bool
) {
self.message = message
self.underlyingLocation = UnsafeSourceLocation(location)
self.completelyErroneous = completelyErroneous
}
}
/// Interface for the Swift compiler.
///
/// Attempt to lex a regex literal string.
///
/// - Parameters:
/// - start: The pointer at which to start lexing the literal.
/// - bufferEnd: A pointer to the end of the buffer, which should not be lexed
/// past.
/// - mustBeRegex: Whether we expect a regex literal to be lexed here. If
/// `false`, a regex literal will only be lexed if it does not
/// produce an error.
///
/// - Returns: If a regex literal was lexed, `resumePtr` specifies where to
/// resume lexing and `error` specifies a lexing error to emit. If
/// a regex literal was not lexed, `nil` is returned.
///
@_spi(CompilerInterface)
public func swiftCompilerLexRegexLiteral(
start: UnsafeRawPointer, bufferEnd: UnsafeRawPointer, mustBeRegex: Bool
) -> (resumePtr: UnsafeRawPointer, error: CompilerLexError?)? {
do {
let (_, _, endPtr) = try lexRegex(start: start, end: bufferEnd)
return (resumePtr: endPtr, error: nil)
} catch let error as DelimiterLexError {
if !mustBeRegex {
// This token can be something else. Let the client fallback.
return nil
}
let completelyErroneous: Bool
switch error.kind {
case .unterminated, .multilineClosingNotOnNewline:
// These can be recovered from.
completelyErroneous = false
case .unprintableASCII, .invalidUTF8:
// We don't currently have good recovery behavior for these.
completelyErroneous = true
case .unknownDelimiter:
// An unknown delimiter should be recovered from, as we may want to try
// lex something else.
return nil
}
// For now every lexer error is emitted at the starting delimiter.
let compilerError = CompilerLexError(
message: "\(error)", location: start,
completelyErroneous: completelyErroneous
)
return (error.resumePtr, compilerError)
} catch {
fatalError("Should be a DelimiterLexError")
}
}
@_spi(CompilerInterface)
public struct CompilerParseError: Error {
public var message: String
public var location: String.Index?
}
/// Interface for the Swift compiler.
///
/// Attempt to parse a regex literal string.
///
/// - Parameters:
/// - input: The regex input string, including delimiters.
/// - captureBufferOut: A buffer into which the captures of the regex will
/// be encoded into upon a successful parse.
///
/// - Returns: The string to emit along with its version number.
/// - Throws: `CompilerParseError` if there was a parsing error.
@_spi(CompilerInterface)
public func swiftCompilerParseRegexLiteral(
_ input: String, captureBufferOut: UnsafeMutableRawBufferPointer
) throws -> (regexToEmit: String, version: Int) {
do {
let ast = try parseWithDelimiters(input)
// Serialize the capture structure for later type inference.
assert(captureBufferOut.count >= input.utf8.count)
ast.captureStructure.encode(to: captureBufferOut)
// For now we just return the input as the regex to emit. This could be
// changed in the future if need to back-deploy syntax to something already
// known to the matching engine, or otherwise change the format. Note
// however that it will need plumbing through on the compiler side.
return (regexToEmit: input, version: currentRegexLiteralFormatVersion)
} catch {
throw CompilerParseError(
message: "cannot parse regular expression: \(String(describing: error))",
location: (error as? LocatedErrorProtocol)?.location.start
)
}
}
|
