Fix swift 6 concurrency issues (#107)

* fix: swift-tools-version declaration

* feat: add Sendable comformance to Node and its dependant types

* fix: Xcode 15 errors

updated swift-snapshot-testing

* refactor: fix snapshot-testing rename warnings

* test with swift:6.0-focal

Makefile

@@ -3,7 +3,7 @@ test-linux:
 		--rm \
 		-v "$(PWD):$(PWD)" \
 		-w "$(PWD)" \
-		swift:5.7-focal \
+		swift:6.0-focal \
 		bash -c 'swift test'
 
 test-macos: xcodeproj

Package.resolved

@@ -1,16 +1,24 @@
 {
-  "object": {
-    "pins": [
-      {
-        "package": "swift-snapshot-testing",
-        "repositoryURL": "https://github.com/pointfreeco/swift-snapshot-testing.git",
-        "state": {
-          "branch": null,
-          "revision": "cef5b3f6f11781dd4591bdd1dd0a3d22bd609334",
-          "version": "1.11.0"
-        }
+  "originHash" : "c2217f3a9bfb04515bca941987fb8e52aa0d2033cd77f82c6ff0f91a868fe948",
+  "pins" : [
+    {
+      "identity" : "swift-snapshot-testing",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/pointfreeco/swift-snapshot-testing.git",
+      "state" : {
+        "revision" : "7b0bbbae90c41f848f90ac7b4df6c4f50068256d",
+        "version" : "1.17.5"
       }
-    ]
-  },
-  "version": 1
+    },
+    {
+      "identity" : "swift-syntax",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/swiftlang/swift-syntax",
+      "state" : {
+        "revision" : "0687f71944021d616d34d922343dcef086855920",
+        "version" : "600.0.1"
+      }
+    }
+  ],
+  "version" : 3
 }

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.5
+// swift-tools-version: 5.5
 import PackageDescription
 
 let package = Package(
@@ -17,7 +17,7 @@ let package = Package(
       targets: ["HtmlSnapshotTesting"]),
   ],
   dependencies: [
-    .package(url: "https://github.com/pointfreeco/swift-snapshot-testing", from: "1.11.0")
+    .package(url: "https://github.com/pointfreeco/swift-snapshot-testing", from: "1.11.1")
   ],
   targets: [
     .target(

Sources/HtmlSnapshotTesting/HtmlSnapshotTesting.swift

@@ -1,5 +1,5 @@
 import Html
-import SnapshotTesting
+@preconcurrency import SnapshotTesting
 
 extension Snapshotting where Value == [Node], Format == String {
   public static var html: Snapshotting {

Tests/HtmlSnapshotTestingTests/HtmlSnapshotTestingTests.swift

@@ -496,7 +496,7 @@ final class SnapshotTestingTests: XCTestCase {
       )
     )
 
-    assertSnapshot(matching: doc, as: .html)
+    assertSnapshot(of: doc, as: .html)
   }
 
   func testSnapshots() {
@@ -642,6 +642,6 @@ final class SnapshotTestingTests: XCTestCase {
       .video(.track(src: "track1"), transparent: "Fallback"),
     ]
 
-    assertSnapshot(matching: doc, as: .html)
+    assertSnapshot(of: doc, as: .html)
   }
 }