Randomness in Stdlib methods (#73).

Sources/RandomIntKit/FuzzerInt.swift

@@ -23,7 +23,7 @@ import CoreKit
 ///
 /// - Important: It may use a different algorithm in the future.
 ///
-@frozen public struct FuzzerInt: Randomness, Sendable {
+@frozen public struct FuzzerInt: Equatable, Interoperable, Randomness, Sendable {
 
     //=------------------------------------------------------------------------=
     // MARK: State
@@ -39,6 +39,14 @@ import CoreKit
         self.state = (seed)
     }
 
+    @inlinable public init(_ source: consuming Stdlib) {
+        self = source.base
+    }
+
+    @inlinable public consuming func stdlib() -> Stdlib {
+        Stdlib(self)
+    }
+
     //=------------------------------------------------------------------------=
     // MARK: Utilities
     //=------------------------------------------------------------------------=
@@ -50,4 +58,33 @@ import CoreKit
         next = (next ^ (next &>> 27)) &* 0x94d049bb133111eb
         return (next ^ (next &>> 31))
     }
+
+    //*========================================================================*
+    // MARK: * Stdlib
+    //*========================================================================*
+
+    @frozen public struct Stdlib: Swift.RandomNumberGenerator {
+
+        //=--------------------------------------------------------------------=
+        // MARK: State
+        //=--------------------------------------------------------------------=
+
+        @usableFromInline var base: FuzzerInt
+
+        //=--------------------------------------------------------------------=
+        // MARK: Initializers
+        //=--------------------------------------------------------------------=
+
+        @inlinable init(_ base: consuming FuzzerInt) {
+            self.base = base
+        }
+
+        //=--------------------------------------------------------------------=
+        // MARK: Utilities
+        //=--------------------------------------------------------------------=
+
+        @inlinable public mutating func next() -> Swift.UInt64 {
+            Swift.UInt64(self.base.next(as: U64.self))
+        }
+    }
 }

Sources/RandomIntKit/RandomInt.swift

@@ -19,20 +19,30 @@ import CoreKit
 ///
 /// It uses Swift's `SystemRandomNumberGenerator`.
 ///
-@frozen public struct RandomInt: Randomness, Sendable {
+@frozen public struct RandomInt: Interoperable, Randomness, Sendable {
 
+    public typealias Stdlib = Swift.SystemRandomNumberGenerator
+
     //=------------------------------------------------------------------------=
     // MARK: State
     //=------------------------------------------------------------------------=
 
-    @usableFromInline var base: SystemRandomNumberGenerator
+    @usableFromInline var base: Stdlib
 
     //=------------------------------------------------------------------------=
     // MARK: Initializers
     //=------------------------------------------------------------------------=
 
     @inlinable public init() {
-        self.base = SystemRandomNumberGenerator()
+        self.base = Stdlib()
+    }
+
+    @inlinable public init(_ source: consuming Stdlib) {
+        self.base = source
+    }
+
+    @inlinable public consuming func stdlib() -> Stdlib {
+        self.base
     }
 
     //=------------------------------------------------------------------------=

Tests/RandomIntKitTests/FuzzerInt.swift

@@ -21,32 +21,50 @@ final class FuzzerIntTests: XCTestCase {
     // MARK: Tests
     //=------------------------------------------------------------------------=
 
+    func testMetadata() {
+        Test().yay(FuzzerInt.self as Any is any Randomness.Type)
+        Test().yay(FuzzerInt.Stdlib.self as Any is any Swift.RandomNumberGenerator.Type)
+    }
+
     func testSeeds() {
-        var randomness: FuzzerInt
+        var randomness = FuzzerInt(seed: 0)
+
+        func expect(_ expectation: U64, line: UInt = #line) {
+            var copy    = randomness
+            var stdlibX = randomness.stdlib
+            var stdlibY = randomness.stdlib()
+
+            Test(line: line).same(randomness, copy)
+            Test(line: line).same(randomness .next(),       (expectation), "normal")
+            Test(line: line).same(copy.stdlib.next(), UInt64(expectation), "stdlib modify")
+            Test(line: line).same(((stdlibX)).next(), UInt64(expectation), "stdlib mutating read")
+            Test(line: line).same(((stdlibY)).next(), UInt64(expectation), "stdlib consuming get")
+            Test(line: line).same(randomness, copy)
+        }
 
         randomness = .init(seed:  0)
-        Test().same(randomness.next(), 16294208416658607535)
-        Test().same(randomness.next(), 07960286522194355700)
-        Test().same(randomness.next(), 00487617019471545679)
-        Test().same(randomness.next(), 17909611376780542444)
+        expect(16294208416658607535)
+        expect(07960286522194355700)
+        expect(00487617019471545679)
+        expect(17909611376780542444)
 
         randomness = .init(seed:  1)
-        Test().same(randomness.next(), 10451216379200822465)
-        Test().same(randomness.next(), 13757245211066428519)
-        Test().same(randomness.next(), 17911839290282890590)
-        Test().same(randomness.next(), 08196980753821780235)
+        expect(10451216379200822465)
+        expect(13757245211066428519)
+        expect(17911839290282890590)
+        expect(08196980753821780235)
 
         randomness = .init(seed: ~1)
-        Test().same(randomness.next(), 17519071339639777313)
-        Test().same(randomness.next(), 13427082724269423081)
-        Test().same(randomness.next(), 15047954047655532813)
-        Test().same(randomness.next(), 02229658653670313015)
+        expect(17519071339639777313)
+        expect(13427082724269423081)
+        expect(15047954047655532813)
+        expect(02229658653670313015)
 
         randomness = .init(seed: ~0)
-        Test().same(randomness.next(), 16490336266968443936)
-        Test().same(randomness.next(), 16834447057089888969)
-        Test().same(randomness.next(), 04048727598324417001)
-        Test().same(randomness.next(), 07862637804313477842)
+        expect(16490336266968443936)
+        expect(16834447057089888969)
+        expect(04048727598324417001)
+        expect(07862637804313477842)
 
         randomness = .init(seed:  0)
         var unique = Set<U64>()

Tests/RandomIntKitTests/RandomInt.swift

@@ -0,0 +1,28 @@
+//=----------------------------------------------------------------------------=
+// This source file is part of the Ultimathnum open source project.
+//
+// Copyright (c)  2023 Oscar Byström Ericsson
+// Licensed under Apache License, Version 2.0
+//
+// See http://www.apache.org/licenses/LICENSE-2.0 for license information.
+//=----------------------------------------------------------------------------=
+
+import CoreKit
+import RandomIntKit
+import TestKit
+
+//*============================================================================*
+// MARK: * Random Int
+//*============================================================================*
+
+final class RandomIntTests: XCTestCase {
+
+    //=------------------------------------------------------------------------=
+    // MARK: Tests
+    //=------------------------------------------------------------------------=
+
+    func testMetadata() {
+        Test().yay(RandomInt.self as Any is any Randomness.Type)
+        Test().yay(RandomInt.Stdlib.self as Any is any Swift.RandomNumberGenerator.Type)
+    }
+}