Use ISO8601FormatStyle on Linux

Author: vnixx

Sources/ReerJSON/JSONDecoderImpl.swift

@@ -260,12 +260,21 @@ final class JSONDecoderImpl: Decoder {
             return Date(timeIntervalSince1970: double / 1000.0)
         case .iso8601:
             let string = try unboxString(from: value, for: codingPathNode, additionalKey)
+            #if os(Linux)
+            guard let date = try? Date.ISO8601FormatStyle().parse(string) else {
+                throw DecodingError.dataCorrupted(.init(
+                    codingPath: codingPathNode.path(byAppending: additionalKey),
+                    debugDescription: "Expected date string to be ISO8601-formatted."
+                ))
+            }
+            #else
             guard let date = _iso8601Formatter.date(from: string) else {
                 throw DecodingError.dataCorrupted(.init(
                     codingPath: codingPathNode.path(byAppending: additionalKey),
                     debugDescription: "Expected date string to be ISO8601-formatted."
                 ))
             }
+            #endif
             return date
         case .formatted(let formatter):
             let string = try unboxString(from: value, for: codingPathNode, additionalKey)

Sources/ReerJSON/Utilities.swift

@@ -146,13 +146,7 @@ extension Optional {
     }
 }
 
-#if os(Linux)
-nonisolated(unsafe) let _iso8601Formatter: ISO8601DateFormatter = {
-    let formatter = ISO8601DateFormatter()
-    formatter.formatOptions = .withInternetDateTime
-    return formatter
-}()
-#else
+#if !os(Linux)
 nonisolated(unsafe) let _iso8601Formatter: JJLISO8601DateFormatter = {
     let formatter = JJLISO8601DateFormatter()
     formatter.formatOptions = .withInternetDateTime