Support none / one / multiple fractional seconds

README.md

@@ -15,6 +15,10 @@ It currently consists of
 
 # Release Notes
 BOAT is still under development and subject to change.
+## 0.17.46
+* boat-scaffold
+  * Enhanced ISO8601 Date Formatting with Fractional Seconds Support for Swift template.
+    * The `OpenISO8601DateFormatter` template now supports parsing and formatting ISO8601 dates with none, one, or multiple fractional seconds in Swift 5. This enhancement provides greater flexibility and precision when working with date and time values, accommodating various use cases that require different levels of fractional second accuracy.
 ## 0.17.36
 * Lint rule `B014` doesn't throw a null exception when parsing a string array property in a schema.  
 ## 0.17.35

boat-scaffold/src/main/templates/boat-swift5/OpenISO8601DateFormatter.mustache

@@ -18,6 +18,15 @@ import Foundation
         return formatter
     }()
 
+    // Primary formatter with fractional seconds
+    private static let sharedDateFormatter: DateFormatter = {
+        let formatter = DateFormatter()
+        formatter.calendar = Calendar(identifier: .iso8601)
+        formatter.locale = Locale(identifier: "en_US_POSIX")
+        formatter.timeZone = TimeZone(secondsFromGMT: 0)
+        return formatter
+    }()
+
     private func setup() {
         calendar = Calendar(identifier: .iso8601)
         locale = Locale(identifier: "en_US_POSIX")
@@ -39,6 +48,33 @@ import Foundation
         if let result = super.date(from: string) {
             return result
         }
-        return OpenISO8601DateFormatter.withoutSeconds.date(from: string)
+        if let result = OpenISO8601DateFormatter.withoutSeconds.date(from: string) {
+            return result
+        }
+        return OpenISO8601DateFormatter.parseDate(from: string)
+    }
+
+    private static func parseDate(from dateString: String) -> Date? {
+        // Base date format
+        let baseFormat = "yyyy-MM-dd'T'HH:mm:ss"
+
+        // Create an instance of DateFormatter for parsing
+        let dateFormatter = OpenISO8601DateFormatter.sharedDateFormatter
+
+        // Check for fractional seconds by locating the dot
+        guard let dotIndex = dateString.firstIndex(of: ".") else {
+            // No fractional seconds, use base format
+            dateFormatter.dateFormat = baseFormat
+            return dateFormatter.date(from: dateString)
+        }
+
+        // Extract fractional part length
+        let fractionLength = dateString[dateString.index(after: dotIndex)...].count
+
+        // Construct the date format with fractional seconds
+        let fractionalFormat = String(repeating: "S", count: fractionLength)
+        dateFormatter.dateFormat = "\(baseFormat).\(fractionalFormat)"
+
+        return dateFormatter.date(from: dateString)
     }
-}
+}