Add map of A1 to A1 extension to support moves literals

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 1.0.4
+
+- Added support for A1 mapping as an extension on Map<String,String> to Map<A1,A1> to assist with A1 moves
+
 ## 1.0.3
 
 - Added support for A1 as an extension on Set to simplify creating an a1 set from String 

lib/src/a1.dart

@@ -248,6 +248,8 @@ extension StringListA1Extension on List<String> {
   Iterable<A1> get a1 => map((e) => e.a1);
 }
 
+/// This extension allows a [Set] of [String]s to be converted to
+/// a [Set] of [A1]
 extension StringSetA1Extension on Set<String> {
   /// Return a [Set<A1>] from the current [Set<String>] or throw
   /// a [FormatException] see [A1.parse].
@@ -257,3 +259,15 @@ extension StringSetA1Extension on Set<String> {
   /// ```
   Set<A1> get a1 => map((e) => e.a1).toSet();
 }
+
+/// This extension allows a [Map<String,String>] to be converted to
+/// a [Map<A1,A1> to assist with cell movement tracking
+extension MapA1Extension on Map<String, String> {
+  /// Return a [Map<A1,A1>] from the current [Map<String,String>] or throw
+  /// a [FormatException] see [A1.parse].
+  /// Example:
+  /// ```dart
+  /// Map<A1,A1> moves = {'a1':'b2','c3':'c4'}.a1; // Map<A1,A1>[A1:B2,C3:C4]
+  /// ```
+  Map<A1, A1> get a1 => map((key, value) => MapEntry(key.a1, value.a1));
+}

pubspec.yaml

@@ -1,5 +1,5 @@
 name: a1
-version: 1.0.3
+version: 1.0.4
 
 homepage: https://pub.dev/packages/a1
 repository: https://github.com/sjhorn/a1

test/a1_test.dart

@@ -154,6 +154,11 @@ void main() {
       final a1Set = {'a1', 'B2', 'c3'}.a1;
       expect(a1Set, containsAll({'a1'.a1, 'B2'.a1, 'c3'.a1}));
     });
+    test('Map of String:String strings to Map of A1:A1s', () {
+      final moves = {'a1': 'd1', 'B2': 'c3'}.a1;
+      expect(moves, containsPair('A1'.a1, 'D1'.a1));
+      expect(moves, containsPair('B2'.a1, 'C3'.a1));
+    });
     test('isLetter', () {
       expect('A'.codeUnits.first.isA1Letter, isTrue);
       expect('@'.codeUnits.first.isA1Letter, isFalse);