Convert all tests from XCTest to SwiftTesting (#198)

* Update CI and docs theme

* Require Swift 6.1, enable InternalImportsByDefault, choose most performant version of StringProtocol.replacing(_:with:) based on platform

* Convert all tests from XCTest to SwiftTesting

Author: gwynne

.github/workflows/test.yml

@@ -21,7 +21,7 @@ jobs:
     permissions:
       contents: read
     runs-on: ubuntu-latest
-    container: swift:6.2-noble
+    container: swift:6.3-noble
     steps:
       - name: Check out sql-kit
         uses: actions/checkout@v6
@@ -54,7 +54,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        swift-image: ['swift:6.2-noble']
+        swift-image: ['swift:6.3-noble']
         driver:
           - { sqlkit: 'sqlite-kit',   fluent: 'fluent-sqlite-driver' }
           - { sqlkit: 'mysql-kit',    fluent: 'fluent-mysql-driver' }

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:6.0
+// swift-tools-version:6.1
 import PackageDescription
 
 let package = Package(
@@ -38,6 +38,8 @@ let package = Package(
         .testTarget(
             name: "SQLKitTests",
             dependencies: [
+                .product(name: "NIOCore", package: "swift-nio"),
+                .product(name: "NIOEmbedded", package: "swift-nio"),
                 .target(name: "SQLKit"),
                 .target(name: "SQLKitBenchmark"),
             ],
@@ -48,7 +50,7 @@ let package = Package(
 
 var swiftSettings: [SwiftSetting] { [
     .enableUpcomingFeature("ExistentialAny"),
-    // .enableUpcomingFeature("InternalImportsByDefault"),
+    .enableUpcomingFeature("InternalImportsByDefault"),
     .enableUpcomingFeature("MemberImportVisibility"),
     .enableUpcomingFeature("InferIsolatedConformances"),
     // .enableUpcomingFeature("NonisolatedNonsendingByDefault"),

Sources/SQLKit/Docs.docc/theme-settings.json

@@ -1,16 +1,19 @@
 {
   "theme": {
-    "aside": { "border-radius": "16px", "border-width": "3px", "border-style": "double" },
     "border-radius": "0",
+    "aside":  { "border-radius": "16px", "border-width": "3px", "border-style": "double" },
     "button": { "border-radius": "16px", "border-width": "1px", "border-style": "solid" },
     "code":   { "border-radius": "16px", "border-width": "1px", "border-style": "solid" },
     "color": {
-      "sqlkit": { "dark": "hsl(32, 77%, 63%)", "light": "hsl(32, 80%, 60%)" },
-      "documentation-intro-fill": "radial-gradient(circle at top, var(--color-sqlkit) 30%, #000 100%)",
+      "sqlkit": {
+        "dark":  "hsl(32, 77%, 63%)",
+        "light": "hsl(32, 80%, 60%)"
+      },
+      "documentation-intro-fill": {
+        "dark":  "radial-gradient(circle at top, var(--color-sqlkit) 0%, #000000 100%)",
+        "light": "radial-gradient(circle at top, var(--color-sqlkit) 0%, #f0f0f0 100%)"
+      },
       "documentation-intro-accent": "var(--color-sqlkit)",
-      "hero-eyebrow": "white",
-      "documentation-intro-figure": "white",
-      "hero-title": "white",
       "logo-base":  { "dark": "#fff", "light": "#000" },
       "logo-shape": { "dark": "#000", "light": "#fff" },
       "fill":       { "dark": "#000", "light": "#fff" }

Sources/SQLKit/Utilities/StringHandling.swift

@@ -1,9 +1,7 @@
 extension StringProtocol where Self: RangeReplaceableCollection, Self.Element: Equatable {
-    /// Provides a version of `StringProtocol.firstRange(of:)` which is guaranteed to be available on
-    /// pre-Ventura Apple platforms.
+    /// Provides a version of `StringProtocol.firstRange(of:)` guaranteed to be available.
     @inlinable
     func sqlkit_firstRange(of other: some StringProtocol) -> Range<Self.Index>? {
-        /// N.B.: This implementation is apparently some 650% faster than `firstRange(of:)`, at least on macOS...
         guard self.count >= other.count, let starter = other.first else { return nil }
         var index = self.startIndex
         let lastIndex = self.index(self.endIndex, offsetBy: -other.count)
@@ -21,15 +19,17 @@ extension StringProtocol where Self: RangeReplaceableCollection, Self.Element: E
         return nil
     }
 
-    /// Provides a version of `StringProtocol.replacing(_:with:)` which is guaranteed to be available on
-    /// pre-Ventura Apple platforms.
+    /// Provides a version of `StringProtocol.replacing(_:with:)` which is guaranteed to be available.
+    #if !DEBUG && !canImport(Darwin)
+    @inline(__always)
+    #endif
     @inlinable
     func sqlkit_replacing(_ search: some StringProtocol, with replacement: some StringProtocol) -> String {
-        /// N.B.: Even on Ventura/Sonoma, the handwritten implementation is orders of magnitude faster than
-        /// `replacing(_:with:)`, at least as of the time of this writing. Thus we use the handwritten version
-        /// unconditionally. It's still 4x slower than Foundation's version, but that's a lot better than 25x.
+        #if DEBUG || canImport(Darwin)
+        // On Apple platforms, this hand-rolled implementation is MUCH faster (10x or more) than the stdlib version, for some reason.
+        // We also want to use this implementation in debug builds, so that the tests test it rather than the stdlib.
         guard !self.isEmpty, !search.isEmpty, self.count >= search.count else { return .init(self) }
-        
+
         var result = "", prevIndex = self.startIndex
 
         result.reserveCapacity(self.count + replacement.count)
@@ -40,6 +40,10 @@ extension StringProtocol where Self: RangeReplaceableCollection, Self.Element: E
         }
         result.append(contentsOf: self[prevIndex...])
         return result
+        #else
+        // On non-Apple platforms, the stdlib's version is better than our hand-rolled one.
+        return String(self.replacing(search, with: replacement))
+        #endif
     }
 
     /// Returns the string with its first character lowercased.

Sources/SQLKitBenchmark/SQLBenchmarker.swift

@@ -1,6 +1,6 @@
 import Logging
 import NIOCore
-import SQLKit
+public import SQLKit
 import XCTest
 
 public final class SQLBenchmarker: Sendable {