Note Serialization: Handle more edge cases

Apparently parsing a YAML Header + body isn't as trivial as I expected.

lib/storage/serializers.dart

@@ -46,37 +46,37 @@ class MarkdownYAMLSerializer implements NoteSerializer {
   NoteData decode(String str) {
     const startYamlStr = "---\n";
     const endYamlStr = "\n---\n";
-    const emptyYamlHeaderStr = "---\n---\n";
+    const emptyYamlHeaderStr = "---\n---";
 
-    if (str.startsWith(emptyYamlHeaderStr)) {
-      var bodyBeginingPos = emptyYamlHeaderStr.length;
+    if (str == emptyYamlHeaderStr) {
+      return NoteData();
+    }
+    if (str.startsWith(emptyYamlHeaderStr + "\n")) {
+      var bodyBeginingPos = emptyYamlHeaderStr.length + 1;
       if (str[bodyBeginingPos] == '\n') {
         bodyBeginingPos += 1;
       }
       var body = str.substring(bodyBeginingPos);
-      return NoteData(body, LinkedHashMap<String, dynamic>());
+      return NoteData(body);
     }
 
     if (str.startsWith(startYamlStr)) {
       var endYamlPos = str.indexOf(endYamlStr, startYamlStr.length);
       if (endYamlPos == -1) {
-        return NoteData(str, LinkedHashMap<String, dynamic>());
+        // Try without the \n in the endYamlStr
+        const endYamlStrWithoutLineEding = "\n---";
+        if (str.endsWith(endYamlStrWithoutLineEding)) {
+          var yamlText =
+              str.substring(4, str.length - endYamlStrWithoutLineEding.length);
+          var map = _parseYamlText(yamlText);
+          return NoteData("", map);
+        }
+
+        return NoteData(str);
       }
 
       var yamlText = str.substring(4, endYamlPos);
-      var map = <String, dynamic>{};
-
-      try {
-        if (yamlText.isNotEmpty) {
-          var yamlMap = loadYaml(yamlText);
-          yamlMap.forEach((key, value) {
-            map[key] = value;
-          });
-        }
-      } catch (err) {
-        Fimber.d(
-            'MarkdownYAMLSerializer::decode("$yamlText") -> ${err.toString()}');
-      }
+      var map = _parseYamlText(yamlText);
 
       var bodyBeginingPos = endYamlPos + endYamlStr.length;
       if (str[bodyBeginingPos] == '\n') {
@@ -90,6 +90,25 @@ class MarkdownYAMLSerializer implements NoteSerializer {
     return NoteData(str, LinkedHashMap<String, dynamic>());
   }
 
+  LinkedHashMap<String, dynamic> _parseYamlText(String yamlText) {
+    LinkedHashMap<String, dynamic> map = LinkedHashMap<String, dynamic>();
+    if (yamlText.isEmpty) {
+      return map;
+    }
+
+    try {
+      var yamlMap = loadYaml(yamlText);
+      yamlMap.forEach((key, value) {
+        map[key] = value;
+      });
+    } catch (err) {
+      Fimber.d(
+          'MarkdownYAMLSerializer::decode("$yamlText") -> ${err.toString()}');
+    }
+
+    return map;
+  }
+
   @override
   String encode(NoteData note) {
     if (note.props.isEmpty) {

test/serializers_test.dart

@@ -50,7 +50,7 @@ Alright.""";
       expect(actualStr, note.body);
     });
 
-    test('Markdown Serializer with empty YAML and no \\n', () {
+    test('Markdown Serializer with empty YAML and no \\n after body', () {
       var inputNoteStr = """---
 ---
 Alright.""";
@@ -62,6 +62,17 @@ Alright.""";
       expect(actualStr, note.body);
     });
 
+    test('Markdown Serializer with empty YAML and doesn"t end with \\n', () {
+      var inputNoteStr = """---
+---""";
+
+      var serializer = MarkdownYAMLSerializer();
+      var note = serializer.decode(inputNoteStr);
+
+      expect("", note.body);
+      expect(0, note.props.length);
+    });
+
     test('Markdown Serializer YAML Order', () {
       var str = """---
 type: Journal
@@ -140,5 +151,20 @@ Alright.""";
 
       expect(actualStr, note.body);
     });
+
+    test('Only YAML Header without \\n', () {
+      var str = """---
+foo: bar
+---""";
+
+      var serializer = MarkdownYAMLSerializer();
+      var note = serializer.decode(str);
+
+      expect("", note.body);
+      expect({"foo": "bar"}, note.props);
+
+      var actualStr = serializer.encode(note);
+      expect(actualStr, str + '\n\n');
+    });
   });
 }