Smarter output detection for generated projects

Previously, specifying a simple target name for a regular project would
store the (zip) archive in a file matching the target name. Only adding a
slash at the end of the name allows to extract it as a directory. It
turns out that such convention is not easy to catch and if a simple name
is provided on the command-line, the user probably wants to create a
directory with such a name with the content of the project.

Note that if a build file is required and the name does not have any
extension, we still store a file with the required name as auto-detecting
the extension to use is not that easy.

Fixes gh-2056

spring-boot-cli/src/main/java/org/springframework/boot/cli/command/init/ProjectGenerator.java

@@ -48,7 +48,7 @@ class ProjectGenerator {
 		ProjectGenerationResponse response = this.initializrService.generate(request);
 		String fileName = (request.getOutput() != null ? request.getOutput() : response
 				.getFileName());
-		if (request.isExtract()) {
+		if (shouldExtract(request, response)) {
 			if (isZipArchive(response)) {
 				extractProject(response, request.getOutput(), force);
 				return;
@@ -68,6 +68,20 @@ class ProjectGenerator {
 		writeProject(response, fileName, force);
 	}
 
+	/**
+	 * Detect if the project should be extracted.
+	 */
+	private boolean shouldExtract(ProjectGenerationRequest request, ProjectGenerationResponse response) {
+		if (request.isExtract()) {
+			return true;
+		}
+		// An explicit name has been provided for an archive and there is no extension in it
+		if (isZipArchive(response) && request.getOutput() != null && !request.getOutput().contains(".")) {
+			return true;
+		}
+		return false;
+	}
+
 	private boolean isZipArchive(ProjectGenerationResponse entity) {
 		if (entity.getContentType() != null) {
 			try {

spring-boot-cli/src/test/java/org/springframework/boot/cli/command/init/InitCommandTests.java

@@ -114,7 +114,7 @@ public class InitCommandTests extends AbstractHttpClientMockTests {
 		assertEquals(ExitStatus.OK,
 				this.command.run("--extract", folder.getAbsolutePath()));
 		File archiveFile = new File(folder, "test.txt");
-		assertTrue("Archive not extracted properly " + folder.getAbsolutePath()
+		assertTrue("Archive not extracted properly " + archiveFile.getAbsolutePath()
 				+ " not found", archiveFile.exists());
 	}
 
@@ -127,10 +127,50 @@ public class InitCommandTests extends AbstractHttpClientMockTests {
 		mockSuccessfulProjectGeneration(request);
 		assertEquals(ExitStatus.OK, this.command.run(folder.getAbsolutePath() + "/"));
 		File archiveFile = new File(folder, "test.txt");
-		assertTrue("Archive not extracted properly " + folder.getAbsolutePath()
+		assertTrue("Archive not extracted properly " + archiveFile.getAbsolutePath()
 				+ " not found", archiveFile.exists());
 	}
 
+	@Test
+	public void generateProjectArchiveExtractedByDefault() throws Exception {
+		String fileName = UUID.randomUUID().toString();
+		assertFalse("No dot in filename", fileName.contains("."));
+		byte[] archive = createFakeZipArchive("test.txt", "Fake content");
+		MockHttpProjectGenerationRequest request = new MockHttpProjectGenerationRequest(
+				"application/zip", "demo.zip", archive);
+		mockSuccessfulProjectGeneration(request);
+		File file = new File(fileName);
+		File archiveFile = new File(file, "test.txt");
+		try {
+			assertEquals(ExitStatus.OK, this.command.run(fileName));
+			assertTrue("Archive not extracted properly " + archiveFile.getAbsolutePath()
+					+ " not found", archiveFile.exists());
+		}
+		finally {
+			archiveFile.delete();
+			file.delete();
+		}
+	}
+
+	@Test
+	public void generateProjectFileSavedAsFileByDefault() throws Exception {
+		String fileName = UUID.randomUUID().toString();
+		String content = "Fake Content";
+		byte[] archive = content.getBytes();
+		MockHttpProjectGenerationRequest request = new MockHttpProjectGenerationRequest(
+				"application/octet-stream", "pom.xml", archive);
+		mockSuccessfulProjectGeneration(request);
+		File file = new File(fileName);
+		try {
+			assertEquals(ExitStatus.OK, this.command.run(fileName));
+			assertTrue("File not saved properly", file.exists());
+			assertTrue("Should not be a directory", file.isFile());
+		}
+		finally {
+			file.delete();
+		}
+	}
+
 	@Test
 	public void generateProjectAndExtractUnsupportedArchive() throws Exception {
 		File folder = this.temporaryFolder.newFolder();