🐛 Don't consider an app outdated if the update can't be installed on the current OS

Fixes #420

Sources/MasKit/Models/SoftwareProduct.swift

@@ -24,7 +24,19 @@ extension SoftwareProduct {
         appName.isEmpty ? bundleIdentifier : appName
     }
 
+    /// Determines whether the app is considered outdated. Updates that require a higher OS version are excluded.
+    /// - Parameter storeApp: App from search result.
+    /// - Returns: true if the app is outdated; false otherwise.
     func isOutdatedWhenComparedTo(_ storeApp: SearchResult) -> Bool {
+        // Only look at min OS version if we have one
+        if let osVersion = Version(storeApp.minimumOsVersion) {
+            let requiredVersion = OperatingSystemVersion(majorVersion: osVersion.major, minorVersion: osVersion.minor, patchVersion: osVersion.patch)
+            // Don't consider an app outdated if the version in the app store requires a higher OS version.
+            guard ProcessInfo.processInfo.isOperatingSystemAtLeast(requiredVersion) else {
+                return false
+            }
+        }
+
         // The App Store does not enforce semantic versioning, but we assume most apps follow versioning
         // schemes that increase numerically over time.
         guard let semanticBundleVersion = Version(tolerant: bundleVersion),

Tests/MasKitTests/Models/SoftwareProductSpec.swift

@@ -0,0 +1,38 @@
+//
+//  SoftwareProductSpec.swift
+//  MasKitTests
+//
+//  Created by Ben Chatelain on 9/30/21.
+//  Copyright © 2018 mas-cli. All rights reserved.
+//
+
+import Foundation
+import Nimble
+import Quick
+
+@testable import MasKit
+
+public class SoftwareProductSpec: QuickSpec {
+    override public func spec() {
+        beforeSuite {
+            MasKit.initialize()
+        }
+        describe("software product") {
+            let app = SoftwareProductMock(appName: "App", bundleIdentifier: "", bundlePath: "", bundleVersion: "1.0.0", itemIdentifier: 111)
+
+            let currentApp = SearchResult(version: "1.0.0")
+            let appUpdate = SearchResult(version: "2.0.0")
+            let higherOs = SearchResult(minimumOsVersion: "99.0.0", version: "3.0.0")
+
+            it("is not outdated there is no new version available") {
+                expect(app.isOutdatedWhenComparedTo(currentApp)) == false
+            }
+            it("is outdated when there is a new version available") {
+                expect(app.isOutdatedWhenComparedTo(appUpdate)) == true
+            }
+            it("is not outdated when the new version requires a higher OS version") {
+                expect(app.isOutdatedWhenComparedTo(higherOs)) == false
+            }
+        }
+    }
+}