feat: Change to Swift 6 strict concurrency

.github/workflows/documentation.yml

@@ -11,7 +11,7 @@ on:
 jobs:
   deploy_docs:
     name: Generate Documentation
-    runs-on: macos-15
+    runs-on: macos-26
     steps:
       - name: Checkout the repository
         uses: actions/checkout@v6

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.9
+// swift-tools-version:6.1
 
 import PackageDescription
 

Source/API/Graphics/PDFLineStyle.swift

@@ -13,7 +13,7 @@
 #endif
 
 /// Structure defining how a line should be drawn into graphics context
-public struct PDFLineStyle: Hashable {
+public struct PDFLineStyle: Hashable, Sendable {
     /// Type of the line
     public var type: PDFLineType
 

Source/API/Graphics/PDFLineType.swift

@@ -7,7 +7,7 @@
 //
 
 /// Different types of lines
-public enum PDFLineType: String {
+public enum PDFLineType: String, Sendable {
     /// No visible line
     case none
 

Source/API/Image/PDFImageOptions.swift

@@ -19,7 +19,7 @@
  * )
  * ```
  */
-public struct PDFImageOptions: OptionSet, Hashable {
+public struct PDFImageOptions: OptionSet, Hashable, Sendable {
     /// nodoc
     public let rawValue: Int
 

Source/API/Table/PDFTableCell.swift

@@ -7,7 +7,7 @@
 //
 
 /// An instance of a table cell
-public class PDFTableCell: PDFDocumentObject {
+public class PDFTableCell: PDFDocumentObject, @unchecked Sendable {
     /**
      * Content of this cell, can be different kinds of data inside a `PDFTableContent` object.
      *

Source/API/Table/Style/PDFTableCellBorders.swift

@@ -7,7 +7,7 @@
 //
 
 /// Structure used to style the border lines of a ``PDFTableCell``
-public struct PDFTableCellBorders: Hashable {
+public struct PDFTableCellBorders: Hashable, Sendable {
     /// Style of left edge line
     public var left: PDFLineStyle
 

Source/API/Table/Style/PDFTableCellStyle.swift

@@ -13,7 +13,7 @@
 #endif
 
 /// Structure used to manage the custom style of a ``PDFTableCell``
-public struct PDFTableCellStyle: Hashable {
+public struct PDFTableCellStyle: Hashable, @unchecked Sendable {
     /// The cell fill (background) color and the text color
     public var colors: (fill: Color, text: Color)
 

Source/API/Utils/CrossPlattformGraphics.swift

@@ -74,12 +74,12 @@
         }
     }
 
-    public struct RectCorner: OptionSet {
-        public static var topLeft: RectCorner = .init(rawValue: 1 << 0)
-        public static var topRight: RectCorner = .init(rawValue: 1 << 1)
-        public static var bottomLeft: RectCorner = .init(rawValue: 1 << 2)
-        public static var bottomRight: RectCorner = .init(rawValue: 1 << 3)
-        public static var allCorners: RectCorner = .init(rawValue: (1 << 4) - 1)
+    public struct RectCorner: OptionSet, Sendable {
+        public static let topLeft: RectCorner = .init(rawValue: 1 << 0)
+        public static let topRight: RectCorner = .init(rawValue: 1 << 1)
+        public static let bottomLeft: RectCorner = .init(rawValue: 1 << 2)
+        public static let bottomRight: RectCorner = .init(rawValue: 1 << 3)
+        public static let allCorners: RectCorner = .init(rawValue: (1 << 4) - 1)
 
         let value: Int
 

Tests/TPPDFTests/Graphics/PDFGraphics_Spec.swift

@@ -132,7 +132,7 @@ class PDFGraphics_Spec: QuickSpec {
     }
     // swiftlint:enable closure_body_length function_body_length
 
-    static var allTests = [
+    static let allTests = [
         ("spec", spec),
     ]
 }

Tests/TPPDFTests/Graphics/PDFLineSeparatorObject+Equatable_Spec.swift

@@ -30,7 +30,7 @@ class PDFLineSeparatorObject_Equatable_Spec: QuickSpec {
         }
     }
 
-    static var allTests = [
+    static let allTests = [
         ("spec", spec),
     ]
 }

Tests/TPPDFTests/Graphics/PDFLineSeparatorObject_Spec.swift

@@ -55,7 +55,7 @@ class PDFLineSeparatorObject_Spec: QuickSpec {
         }
     }
 
-    static var allTests = [
+    static let allTests = [
         ("spec", spec),
     ]
 }

Tests/TPPDFTests/Graphics/PDFLineStyle_Equatable_Spec.swift

@@ -45,7 +45,7 @@ class PDFLineStyle_Equatable_Spec: QuickSpec {
         }
     }
 
-    static var allTests = [
+    static let allTests = [
         ("spec", spec),
     ]
 }

Tests/TPPDFTests/Graphics/PDFLineStyle_Spec.swift

@@ -64,7 +64,7 @@ class PDFLineStyle_Spec: QuickSpec {
     }
     // swiftlint:enable closure_body_length
 
-    static var allTests = [
+    static let allTests = [
         ("spec", spec),
     ]
 }

Tests/TPPDFTests/Graphics/PDFLineType_Spec.swift

@@ -15,7 +15,7 @@ class PDFLineType_Spec: QuickSpec {
         describe("PDFLineType") {}
     }
 
-    static var allTests = [
+    static let allTests = [
         ("spec", spec),
     ]
 }

Tests/TPPDFTests/PDFGenerator+Generation_Spec.swift

@@ -126,7 +126,7 @@ class PDFGenerator_Generation_Spec: QuickSpec {
 
                 it("should render object") {
                     class CustomObject: PDFRenderObject {
-                        static var called = false
+                        nonisolated(unsafe) static var called = false
 
                         override func draw(generator _: PDFGenerator, container _: PDFContainer, in _: PDFContext) throws {
                             CustomObject.called = true