Allow overwriting TextEditingValue with folded blocks even with collapsed selection (akvelon#232) (akvelon#233)

* Allow overwriting TextEditingValue with folded blocks even with collapsed selection (akvelon#232)

* Fix an analyzer issue (akvelon#232)

Author: alexeyinkin

example/lib/03.change_language_theme/constants.dart

@@ -1,13 +1,15 @@
 import 'package:highlight/languages/dart.dart';
 import 'package:highlight/languages/go.dart';
 import 'package:highlight/languages/java.dart';
+import 'package:highlight/languages/php.dart';
 import 'package:highlight/languages/python.dart';
 import 'package:highlight/languages/scala.dart';
 
 final builtinLanguages = {
   'dart': dart,
   'go': go,
   'java': java,
+  'php': php,
   'python': python,
   'scala': scala,
 };
@@ -16,6 +18,7 @@ const languageList = <String>[
   'dart',
   'go',
   'java',
+  'php',
   'python',
   'scala',
 ];

lib/src/code/code.dart

@@ -381,10 +381,11 @@ class Code {
     // If there is any folded block that is going to be removed
     // because of `backspace` or `delete`, return unchanged text.
     if (oldSelection.isCollapsed &&
+        visibleAfter.text.length == visibleText.length - 1 &&
         foldedBlocks.any(
-          (element) =>
-              element.lastLine >= firstChangedLine &&
-              element.lastLine <= lastChangedLine,
+          (block) =>
+              block.lastLine >= firstChangedLine &&
+              block.lastLine <= lastChangedLine,
         )) {
       return CodeEditResult(
         fullTextAfter: text,

test/issues/issue_232_test.dart

@@ -0,0 +1,83 @@
+import 'package:flutter/cupertino.dart';
+import 'package:flutter_code_editor/flutter_code_editor.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:highlight/languages/java.dart';
+
+const _fullText = '''
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.beam.learning.katas.commontransforms.filter.filter;
+
+
+import org.apache.beam.learning.katas.util.Log;
+import org.apache.beam.sdk.Pipeline;
+import org.apache.beam.sdk.options.PipelineOptions;
+import org.apache.beam.sdk.options.PipelineOptionsFactory;
+import org.apache.beam.sdk.transforms.Create;
+import org.apache.beam.sdk.transforms.Filter;
+import org.apache.beam.sdk.values.PCollection;
+
+public class Task {
+
+  public static void main(String[] args) {
+    PipelineOptions options = PipelineOptionsFactory.fromArgs(args).create();
+    Pipeline pipeline = Pipeline.create(options);
+
+    PCollection<Integer> numbers =
+        pipeline.apply(Create.of(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));
+
+    PCollection<Integer> output = applyTransform(numbers);
+
+    output.apply(Log.ofElements());
+
+    pipeline.run();
+  }
+
+  static PCollection<Integer> applyTransform(PCollection<Integer> input) {
+    return input.apply(Filter.by(number -> number % 2 == 0));
+  }
+
+}''';
+
+const _newValue = TextEditingValue(
+  text: '''
+public class MyClass {
+  public static void main(String[] args) {
+    System.out.print("OK");
+  }
+}
+''',
+  selection: TextSelection.collapsed(offset: 100),
+);
+
+void main() {
+  test('Issue 232', () {
+    final controller = CodeController(
+      language: java,
+    );
+
+    controller.fullText = _fullText;
+    controller.foldCommentAtLineZero();
+    controller.foldImports();
+
+    controller.value = _newValue;
+
+    expect(controller.value, _newValue);
+  });
+}