admin/UUVPN
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

add

Browse Source
This commit is contained in:
zeus
2025-01-22 16:22:33 +08:00
parent 09b9cec8ec
commit 738c373a77
2534 changed files with 0 additions and 486292 deletions
Download Patch File Download Diff File Expand all files Collapse all files
iOS-SwiftUI-Code/GRDB.swift-6.29.3/GRDB/FTS/FTS3Pattern.swift
-150
View File
@@ -1,150 +0,0 @@
/// A full text pattern for querying FTS3 virtual tables.
///
/// `FTS3Pattern` can be used with both ``FTS3`` and ``FTS4`` tables.
///
/// Related SQLite documentation: <https://www.sqlite.org/fts3.html#full_text_index_queries>
///
/// ## Topics
///
/// ### Creating Raw FTS3 Patterns
///
/// - ``init(rawPattern:)``
///
/// ### Creating FTS3 Patterns from User Input
///
/// - ``init(matchingAllPrefixesIn:)``
/// - ``init(matchingAllTokensIn:)``
/// - ``init(matchingAnyTokenIn:)``
/// - ``init(matchingPhrase:)``
public struct FTS3Pattern: Sendable {
/// The raw pattern string.
///
/// It is guaranteed to be a valid FTS3/4 pattern.
public let rawPattern: String
/// Creates a pattern from a raw pattern string.
///
/// The pattern syntax is documented at <https://www.sqlite.org/fts3.html#full_text_index_queries>
///
/// For example:
///
/// ```swift
/// // OK
/// let pattern = try FTS3Pattern(rawPattern: "and")
///
/// // Throws an error: malformed MATCH expression: [AND]
/// let pattern = try FTS3Pattern(rawPattern: "AND")
/// ```
///
/// - throws: A ``DatabaseError`` if the pattern has an invalid syntax.
public init(rawPattern: String) throws {
// Correctness above all: use SQLite to validate the pattern.
//
// Invalid patterns have SQLite return an error on the first
// call to sqlite3_step() on a statement that matches against
// that pattern.
do {
try DatabaseQueue().inDatabase { db in
try db.execute(literal: """
CREATE VIRTUAL TABLE documents USING fts3();
SELECT * FROM documents WHERE content MATCH \(rawPattern);
""")
}
} catch let error as DatabaseError {
// Remove private SQL & arguments from the thrown error
throw DatabaseError(resultCode: error.extendedResultCode, message: error.message)
}
// Pattern is valid
self.rawPattern = rawPattern
}
/// Creates a pattern that matches any token found in the input string.
///
/// The result is nil if no pattern could be built.
///
/// For example:
///
/// ```swift
/// FTS3Pattern(matchingAnyTokenIn: "") // nil
/// FTS3Pattern(matchingAnyTokenIn: "foo bar") // foo OR bar
/// ```
///
/// - parameter string: The string to turn into an FTS3 pattern.
public init?(matchingAnyTokenIn string: String) {
guard let tokens = try? FTS3.tokenize(string, withTokenizer: .simple),
!tokens.isEmpty
else { return nil }
try? self.init(rawPattern: tokens.joined(separator: " OR "))
}
/// Creates a pattern that matches all tokens found in the input string.
///
/// The result is nil if no pattern could be built.
///
/// For example:
///
/// ```swift
/// FTS3Pattern(matchingAllTokensIn: "") // nil
/// FTS3Pattern(matchingAllTokensIn: "foo bar") // foo bar
/// ```
///
/// - parameter string: The string to turn into an FTS3 pattern.
public init?(matchingAllTokensIn string: String) {
guard let tokens = try? FTS3.tokenize(string, withTokenizer: .simple),
!tokens.isEmpty
else { return nil }
try? self.init(rawPattern: tokens.joined(separator: " "))
}
/// Creates a pattern that matches all token prefixes found in the input
/// string.
///
/// The result is nil if no pattern could be built.
///
/// For example:
///
/// ```swift
/// FTS3Pattern(matchingAllTokensIn: "") // nil
/// FTS3Pattern(matchingAllTokensIn: "foo bar") // foo* bar*
/// ```
///
/// - parameter string: The string to turn into an FTS3 pattern.
public init?(matchingAllPrefixesIn string: String) {
guard let tokens = try? FTS3.tokenize(string, withTokenizer: .simple),
!tokens.isEmpty
else { return nil }
try? self.init(rawPattern: tokens.map { "\($0)*" }.joined(separator: " "))
}
/// Creates a pattern that matches a contiguous string.
///
/// The result is nil if no pattern could be built.
///
/// For example:
///
/// ```swift
/// FTS3Pattern(matchingPhrase: "") // nil
/// FTS3Pattern(matchingPhrase: "foo bar") // "foo bar"
/// ```
///
/// - parameter string: The string to turn into an FTS3 pattern.
public init?(matchingPhrase string: String) {
guard let tokens = try? FTS3.tokenize(string, withTokenizer: .simple),
!tokens.isEmpty
else { return nil }
try? self.init(rawPattern: "\"" + tokens.joined(separator: " ") + "\"")
}
}
extension FTS3Pattern: DatabaseValueConvertible {
public var databaseValue: DatabaseValue {
rawPattern.databaseValue
}
public static func fromDatabaseValue(_ dbValue: DatabaseValue) -> FTS3Pattern? {
String
.fromDatabaseValue(dbValue)
.flatMap { try? FTS3Pattern(rawPattern: $0) }
}
}