dev/integration_tests/flutter_gallery/test/calculator/logic.dart

// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'package:flutter_gallery/demo/calculator/logic.dart';

// ignore: deprecated_member_use
import 'package:test_api/test_api.dart' hide TypeMatcher, isInstanceOf;

void main() {
  test('Test order of operations: 12 + 3 * 4 = 24', () {
    CalcExpression expression = CalcExpression.empty();
    expression = expression.appendDigit(1)!;
    expression = expression.appendDigit(2)!;
    expression = expression.appendOperation(Operation.Addition)!;
    expression = expression.appendDigit(3)!;
    expression = expression.appendOperation(Operation.Multiplication)!;
    expression = expression.appendDigit(4)!;
    expression = expression.computeResult()!;
    expect(expression.state, equals(ExpressionState.Result));
    expect(expression.toString(), equals('24'));
  });

  test('Test floating point 0.1 + 0.2 = 0.3', () {
    CalcExpression expression = CalcExpression.empty();
    expression = expression.appendDigit(0)!;
    expression = expression.appendPoint()!;
    expression = expression.appendDigit(1)!;
    expression = expression.appendOperation(Operation.Addition)!;
    expression = expression.appendDigit(0)!;
    expression = expression.appendPoint()!;
    expression = expression.appendDigit(2)!;
    expression = expression.computeResult()!;
    expect(expression.state, equals(ExpressionState.Result));
    expect(expression.toString(), equals('0.3'));
  });

  test('Test floating point 1.0/10.0 = 0.1', () {
    CalcExpression expression = CalcExpression.empty();
    expression = expression.appendDigit(1)!;
    expression = expression.appendPoint()!;
    expression = expression.appendDigit(0)!;
    expression = expression.appendOperation(Operation.Division)!;
    expression = expression.appendDigit(1)!;
    expression = expression.appendDigit(0)!;
    expression = expression.appendPoint()!;
    expression = expression.appendDigit(0)!;
    expression = expression.computeResult()!;
    expect(expression.state, equals(ExpressionState.Result));
    expect(expression.toString(), equals('0.1'));
  });

  test('Test 1/0 = Infinity', () {
    CalcExpression expression = CalcExpression.empty();
    expression = expression.appendDigit(1)!;
    expression = expression.appendOperation(Operation.Division)!;
    expression = expression.appendDigit(0)!;
    expression = expression.computeResult()!;
    expect(expression.state, equals(ExpressionState.Result));
    expect(expression.toString(), equals('Infinity'));
  });

  test('Test use result in next calculation: 1 + 1 = 2 + 1 = 3 + 1 = 4', () {
    CalcExpression expression = CalcExpression.empty();
    expression = expression.appendDigit(1)!;
    expression = expression.appendOperation(Operation.Addition)!;
    expression = expression.appendDigit(1)!;
    expression = expression.computeResult()!;
    expression = expression.appendOperation(Operation.Addition)!;
    expression = expression.appendDigit(1)!;
    expression = expression.computeResult()!;
    expression = expression.appendOperation(Operation.Addition)!;
    expression = expression.appendDigit(1)!;
    expression = expression.computeResult()!;
    expect(expression.state, equals(ExpressionState.Result));
    expect(expression.toString(), equals('4'));
  });

  test('Test minus -3 - -2 = -1', () {
    CalcExpression expression = CalcExpression.empty();
    expression = expression.appendMinus()!;
    expression = expression.appendDigit(3)!;
    expression = expression.appendMinus()!;
    expression = expression.appendMinus()!;
    expression = expression.appendDigit(2)!;
    expression = expression.computeResult()!;
    expect(expression.state, equals(ExpressionState.Result));
    expect(expression.toString(), equals('-1'));
  });
}