Fix JSON parsing error by making formattedPrice & price optional for SearchResult.

Use new `displayPrice` to get around optional `formattedPrice`. Doesn't handle i18n, but we can clean that up after we completely redo JSON handling.

Resolve #493

Signed-off-by: Ross Goldberg <484615+rgoldberg@users.noreply.github.com>

Author: rgoldberg

Sources/mas/Formatters/AppInfoFormatter.swift

@@ -18,7 +18,7 @@ enum AppInfoFormatter {
         let headline = [
             "\(app.trackName)",
             "\(app.version)",
-            "[\(app.formattedPrice)]",
+            "[\(app.displayPrice)]",
         ]
         .joined(separator: " ")
 

Sources/mas/Formatters/SearchResultFormatter.swift

@@ -29,7 +29,7 @@ enum SearchResultFormatter {
             let version = result.version
 
             if includePrice {
-                output += String(format: "%12lu  %@  (%@)  %@\n", appID, appName, version, result.formattedPrice)
+                output += String(format: "%12lu  %@  (%@)  %@\n", appID, appName, version, result.displayPrice)
             } else {
                 output += String(format: "%12lu  %@  (%@)\n", appID, appName, version)
             }

Sources/mas/Models/SearchResult.swift

@@ -10,16 +10,20 @@ struct SearchResult: Decodable {
     var bundleId: String
     var currentVersionReleaseDate: String
     var fileSizeBytes: String
-    var formattedPrice: String
+    var formattedPrice: String?
     var minimumOsVersion: String
-    var price: Double
+    var price: Double?
     var sellerName: String
     var sellerUrl: String?
     var trackId: AppID
     var trackName: String
     var trackViewUrl: String
     var version: String
 
+    var displayPrice: String {
+        formattedPrice ?? "Unknown"
+    }
+
     init(
         bundleId: String = "",
         currentVersionReleaseDate: String = "",