Testing KeyErrorSequence

src/test/java/fr/nancy/iut/CalcEngineTest.java

@@ -64,4 +64,31 @@ public class CalcEngineTest {
         assertEquals(3, engine.getDisplayValue());
     }
 
+    @Test
+    @DisplayName("Testing error in key sequence;")
+    void testKeySequenceError() {
+        // Make sure the engine is in a valid starting state.
+        engine.clear();
+        // Simulate the key presses: 1 + 2 + 3 =
+        engine.numberPressed(1);
+        engine.plus();
+        engine.numberPressed(2);
+        engine.plus();
+        engine.numberPressed(3);
+        engine.equals();
+        // Intermediate result : 6
+        assertEquals(6, engine.getDisplayValue());
+        engine.plus();
+        engine.minus();
+        // Sequencing error, check to verify everything is in initial state
+        assertEquals(0, engine.getDisplayValue());
+        // We can do operations again
+        // Simulate the presses: 9 - 4 =
+        engine.numberPressed(9);
+        engine.minus();
+        engine.numberPressed(4);
+        engine.equals();
+        // Return the result, which should be 5.
+        assertEquals(5, engine.getDisplayValue());
+    }
 }