Start writing tests for FileController using Mockito.

pom.xml

@@ -143,5 +143,16 @@
       <version>5.7.0</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-junit-jupiter</artifactId>
+      <version>3.6.28</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-core</artifactId>
+      <version>3.6.28</version>
+    </dependency>
   </dependencies>
 </project>

src/main/lombok/org/leumasjaffe/recipe/controller/FileController.java

@@ -71,7 +71,7 @@ public class FileController<T extends Component & FileController.Model> {
 	
 	@SuppressWarnings("resource")
 	@SneakyThrows(IOException.class)
-	private Optional<Writer> getSaved() {
+	Optional<Writer> getSaved() {
 		if (filename != null) {
 			return Optional.of(new FileWriter(filename));
 		} else if (chooser.showOpenDialog(owner) == JFileChooser.APPROVE_OPTION) {
@@ -84,7 +84,7 @@ public class FileController<T extends Component & FileController.Model> {
 	
 	@SuppressWarnings("resource")
 	@SneakyThrows(FileNotFoundException.class)
-	private Optional<Reader> getOpened() {
+	Optional<Reader> getOpened() {
 		if (chooser.showOpenDialog(owner) == JFileChooser.APPROVE_OPTION) {
 			filename = chooser.getSelectedFile();
 			return Optional.of(new FileReader(filename));
@@ -111,7 +111,7 @@ public class FileController<T extends Component & FileController.Model> {
 		}
 	}
 
-	private void errorPopup(final Exception ex) {
+	void errorPopup(final Exception ex) {
 		JOptionPane.showMessageDialog(owner, ex.getLocalizedMessage(),
 				"File Error", JOptionPane.ERROR_MESSAGE);
 	}

src/test/java/org/leumasjaffe/recipe/controller/FileControllerTest.java

@@ -0,0 +1,81 @@
+package org.leumasjaffe.recipe.controller;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+import java.awt.Component;
+import java.awt.ComponentOrientation;
+import java.io.StringReader;
+import java.util.Optional;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.leumasjaffe.recipe.model.Recipe;
+import org.mockito.ArgumentCaptor;
+import org.mockito.InOrder;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.mockito.Spy;
+
+class FileControllerTest {
+	@SuppressWarnings("serial")
+	private static class StubComponent extends Component implements FileController.Model {
+		@Override public void setModel(Recipe model) {}
+	}
+	
+	StubComponent stub;
+	FileController<StubComponent> controller;
+	
+	@BeforeEach
+	void setUp() {
+		stub = mock(StubComponent.class);
+		controller = spy(new FileController<>(stub));
+		// Make sure that any errors are directed into the test case's failure trace,
+		// rather than a JOptionDialog
+		doAnswer(inv -> { throw inv.getArgument(0, Exception.class); })
+			.when(controller).errorPopup(any());
+	}
+	
+	@Test
+	void testCanCreateNewModel() {
+		controller.create();
+		verify(stub).setModel(any(Recipe.class));
+	}
+
+	@Test
+	void testRepeatedCreatesProvideNewObjects() {
+		InOrder inOrder = inOrder(stub);
+		final ArgumentCaptor<Recipe> first = ArgumentCaptor.forClass(Recipe.class);
+		final ArgumentCaptor<Recipe> second = ArgumentCaptor.forClass(Recipe.class);
+
+		controller.create();
+		inOrder.verify(stub).setModel(first.capture());
+
+		controller.create();
+		inOrder.verify(stub).setModel(second.capture());
+		
+		assertNotSame(first.getValue(), second.getValue());
+	}
+
+	@Test
+	void testOpensContentIntoRecipe() {
+		final String data = "{ \"title\": \"Example\" }";
+		doReturn(Optional.of(new StringReader(data))).when(controller).getOpened();
+
+		controller.open();
+		
+		verify(stub).setModel(argThat(r -> r.getTitle().equals("Example")));
+	}
+
+	@Test
+	void testEmitsErrorWithMalformedData() {
+		final String data = "{ \"name\": \"Example\" }";
+		doReturn(Optional.of(new StringReader(data))).when(controller).getOpened();
+		doNothing().when(controller).errorPopup(any());
+
+		controller.open();
+		
+		verify(controller).errorPopup(any());
+	}
+
+}