Merge pull request junit-team#419 from simplyarjen/master

Make TemporaryFolder.createFile fail if the file already exists (Fixes junit-team#413)

src/main/java/org/junit/rules/TemporaryFolder.java

@@ -50,7 +50,9 @@ public void create() throws IOException {
 	 */
 	public File newFile(String fileName) throws IOException {
 		File file= new File(getRoot(), fileName);
-		file.createNewFile();
+		if (!file.createNewFile())
+			throw new IllegalStateException(
+					"a file with the name \'" + fileName + "\' already exists in the test folder");
 		return file;
 	}
 

src/test/java/org/junit/tests/experimental/rules/TempFolderRuleTest.java

@@ -158,6 +158,28 @@ public void recursiveDeleteFolderWithZeroElements() throws IOException {
 		assertFalse(folder.getRoot().exists());
 	}
 
+	public static class NameClashes {
+		@Rule
+		public TemporaryFolder folder= new TemporaryFolder();
+
+		@Test
+		public void fileWithFileClash() throws IOException {
+			folder.newFile("something.txt");
+			folder.newFile("something.txt");
+		}
+
+		@Test
+		public void fileWithFolderTest() throws IOException {
+			folder.newFolder("dummy");
+			folder.newFile("dummy");
+		}
+	}
+
+	@Test
+	public void nameClashesResultInTestFailures() {
+		assertThat(testResult(NameClashes.class), failureCountIs(2));
+	}
+
 	private static final String GET_ROOT_DUMMY= "dummy-getRoot";
 
 	private static final String NEW_FILE_DUMMY= "dummy-newFile";