insertion_test.dart

import 'package:flutter/services.dart';
import 'package:flutter_code_editor/src/code_field/editor_params.dart';
import 'package:flutter_code_editor/src/code_modifiers/insertion.dart';
import 'package:flutter_test/flutter_test.dart';

void main() {
  test('inserts at the start of string correctly', () {
    const modifier = InsertionCodeModifier(openChar: '1', closeString: '23');
    const text = 'Hello World';
    final selection = TextSelection.fromPosition(const TextPosition(offset: 0));
    const editorParams = EditorParams();

    final result = modifier.updateString(text, selection, editorParams);

    expect(result!.text, '123Hello World');
    expect(result.selection.baseOffset, 1);
    expect(result.selection.extentOffset, 1);
  });

  test('inserts in the middle of string correctly', () {
    const modifier = InsertionCodeModifier(openChar: '1', closeString: '23');
    const text = 'Hello World';
    final selection = TextSelection.fromPosition(const TextPosition(offset: 5));
    const editorParams = EditorParams();

    final result = modifier.updateString(text, selection, editorParams);

    expect(result!.text, 'Hello123 World');
    expect(result.selection.baseOffset, 6);
    expect(result.selection.extentOffset, 6);
  });

  test('inserts at the end of string correctly', () {
    const modifier = InsertionCodeModifier(openChar: '1', closeString: '23');
    const text = 'Hello World';
    final selection =
        TextSelection.fromPosition(const TextPosition(offset: text.length));
    const editorParams = EditorParams();

    final result = modifier.updateString(text, selection, editorParams);

    expect(result!.text, 'Hello World123');
    expect(result.selection.baseOffset, text.length + 1);
    expect(result.selection.extentOffset, text.length + 1);
  });

  test('inserts in the middle of string with selection correctly', () {
    const modifier = InsertionCodeModifier(openChar: '1', closeString: '23');
    const text = 'Hello World';
    const selection = TextSelection(
      baseOffset: 5,
      extentOffset: 7,
    );
    const editorParams = EditorParams();

    final result = modifier.updateString(text, selection, editorParams);

    expect(result!.text, 'Hello123orld');
    expect(result.selection.baseOffset, 6);
    expect(result.selection.extentOffset, 6);
  });

  test('inserts at empty string correctly', () {
    const modifier = InsertionCodeModifier(openChar: '1', closeString: '23');
    const text = '';
    final selection = TextSelection.fromPosition(const TextPosition(offset: 0));
    const editorParams = EditorParams();

    final result = modifier.updateString(text, selection, editorParams);

    expect(result!.text, '123');
    expect(result.selection.baseOffset, 1);
    expect(result.selection.extentOffset, 1);
  });
}