Added SPM Support

.gitignore

@@ -32,6 +32,7 @@ xcuserdata
 # Add this line if you want to avoid checking in source code from Swift Package Manager dependencies.
 # Packages/
 .build/
+.swiftpm/
 
 # CocoaPods
 #

Package.swift

@@ -0,0 +1,26 @@
+// swift-tools-version:5.3
+
+import PackageDescription
+
+let package = Package(
+    name: "Solar",
+    products: [
+        .library(name: "Solar", targets: ["Solar"]),
+    ],
+    dependencies: [ ],
+    targets: [
+        .target(
+            name: "Solar",
+            dependencies: [],
+            path: "Solar",
+            exclude: ["Info-iOS.plist", "Info-watchOS.plist"]),
+
+        .testTarget(
+            name: "SolarTests",
+            dependencies: ["Solar"],
+            path: "Solar iOSTests",
+            exclude: ["Info.plist"],
+            resources: [.copy("CorrectResults.json")]
+        ),
+    ]
+)

Solar iOSTests/Solar_iOSTests.swift

@@ -19,8 +19,14 @@ final class Solar_iOSTests: XCTestCase {
     private let testAccuracy: TimeInterval = 60 * 5
 
     private lazy var cities: [City] = {
+        #if SWIFT_PACKAGE
+        let bundle = Bundle.module
+        #else
+        let bundle = Bundle(for: type(of: self))
+        #endif
+
         guard
-            let resultsURLString = Bundle(for: type(of: self)).path(forResource: "CorrectResults", ofType: "json"),
+            let resultsURLString = bundle.path(forResource: "CorrectResults", ofType: "json"),
             let data = try? Data(contentsOf: URL(fileURLWithPath: resultsURLString)),
             let dictionary = try? JSONSerialization.jsonObject(with: data, options: []),
             let cityDictionaries = dictionary as? [[String : Any]]

Solar.xcodeproj/project.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>IDEDidComputeMac32BitWarning</key>
+	<true/>
+</dict>
+</plist>