avoid NPE if project directory does not exist; fixes #10

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/util/Util.java

@@ -138,12 +138,15 @@ public class Util {
     public static void deleteInDirectoryApartFrom(File directory, String... apartFrom) {
         if (directory != null) {
             Set<String> excluded = new HashSet<String>(Arrays.asList(apartFrom));
-            for (File file : directory.listFiles()) {
-                if (!excluded.contains(file.getName())) {
-                    if (file.isDirectory()) {
-                        deleteInDirectory(file);
+            File [] files = directory.listFiles();
+            if (files != null) {
+                for (File file : files) {
+                    if (!excluded.contains(file.getName())) {
+                        if (file.isDirectory()) {
+                            deleteInDirectory(file);
+                        }
+                        file.delete();
                     }
-                    file.delete();
                 }
             }
         }

services/git-bridge/src/test/java/uk/ac/ic/wlgitbridge/WLGitBridgeIntegrationTest.java

@@ -82,6 +82,10 @@ public class WLGitBridgeIntegrationTest {
                 put("pushFailsOnUnexpectedError", new HashMap<String, SnapshotAPIState>() {{
                     put("state", new SnapshotAPIStateBuilder(getResourceAsStream("/pushFailsOnUnexpectedError/state/state.json")).build());
                 }});
+                put("pushSucceedsAfterRemovingInvalidFiles", new HashMap<String, SnapshotAPIState>() {{
+                    put("invalidState", new SnapshotAPIStateBuilder(getResourceAsStream("/pushSucceedsAfterRemovingInvalidFiles/invalidState/state.json")).build());
+                    put("validState", new SnapshotAPIStateBuilder(getResourceAsStream("/pushSucceedsAfterRemovingInvalidFiles/validState/state.json")).build());
+                }});
             }};
 
     @Rule
@@ -497,6 +501,53 @@ public class WLGitBridgeIntegrationTest {
         assertEquals(EXPECTED_OUT_PUSH_UNEXPECTED_ERROR, actual);
     }
 
+    private static final List<String> EXPECTED_OUT_PUSH_INVALID_EXE_FILE =
+        Arrays.asList(
+                "remote: error: invalid files",
+                "remote: hint: You have 1 invalid files in your Overleaf project:",
+                "remote: hint: file1.exe (invalid file extension)",
+                "To http://127.0.0.1:33872/testproj.git",
+                "! [remote rejected] master -> master (invalid files)",
+                "error: failed to push some refs to 'http://127.0.0.1:33872/testproj.git'"
+        );
+
+    @Test
+    public void pushSucceedsAfterRemovingInvalidFiles() throws IOException, GitAPIException, InterruptedException {
+        MockSnapshotServer server = new MockSnapshotServer(3872, getResource("/pushSucceedsAfterRemovingInvalidFiles").toFile());
+        server.start();
+        server.setState(states.get("pushSucceedsAfterRemovingInvalidFiles").get("invalidState"));
+        GitBridgeApp wlgb = new GitBridgeApp(new String[] {
+                makeConfigFile(33872, 3872)
+        });
+        wlgb.run();
+        File dir = folder.newFolder();
+        Process git = runtime.exec("git clone http://127.0.0.1:33872/testproj.git", null, dir);
+        int exitCode = git.waitFor();
+        File testprojDir = new File(dir, "testproj");
+        assertEquals(0, exitCode);
+
+        // try to push invalid file; it should fail
+        assertTrue(FileUtil.gitDirectoriesAreEqual(getResource("/pushSucceedsAfterRemovingInvalidFiles/invalidState/testproj"), testprojDir.toPath()));
+        assertEquals(0, runtime.exec("touch file1.exe", null, testprojDir).waitFor());
+        assertEquals(0, runtime.exec("git add -A", null, testprojDir).waitFor());
+        assertEquals(0, runtime.exec("git commit -m \"push\"", null, testprojDir).waitFor());
+        Process gitPush = runtime.exec("git push", null, testprojDir);
+        int pushExitCode = gitPush.waitFor();
+        assertEquals(1, pushExitCode);
+        List<String> actual = Util.linesFromStream(gitPush.getErrorStream(), 0, "[K");
+        assertEquals(EXPECTED_OUT_PUSH_INVALID_EXE_FILE, actual);
+
+        // remove invalid file and push again; it should succeed this time
+        assertEquals(0, runtime.exec("git rm file1.exe", null, testprojDir).waitFor());
+        assertEquals(0, runtime.exec("git commit -m remove_invalid_file", null, testprojDir).waitFor());
+        server.setState(states.get("pushSucceedsAfterRemovingInvalidFiles").get("validState"));
+        gitPush = runtime.exec("git push", null, testprojDir);
+        pushExitCode = gitPush.waitFor();
+        wlgb.stop();
+        assertEquals(0, pushExitCode);
+        assertTrue(FileUtil.gitDirectoriesAreEqual(getResource("/pushSucceedsAfterRemovingInvalidFiles/validState/testproj"), testprojDir.toPath()));
+    }
+
     private String makeConfigFile(int port, int apiPort) throws IOException {
         File wlgb = folder.newFolder();
         File config = folder.newFile();

services/git-bridge/src/test/resources/uk/ac/ic/wlgitbridge/WLGitBridgeIntegrationTest/pushSucceedsAfterRemovingInvalidFiles/invalidState/state.json

@@ -0,0 +1,34 @@
+[
+	{
+		"project": "testproj",
+		"getDoc": {
+			"versionID": 1,
+			"createdAt": "2014-11-30T18:40:58.123Z",
+			"email": "test@example.com",
+			"name": "Test User"
+		},
+		"getSavedVers": [],
+		"getForVers": [
+			{
+				"versionID": 1,
+				"srcs": [
+                    {
+                    	"content": "content\n",
+                    	"path": "main.tex"
+                    }
+	            ],
+	            "atts": []
+	        }
+		],
+		"push": "success",
+		"postback": {
+			"type": "invalidFiles",
+            "errors": [
+                {
+                    "file": "file1.exe",
+                    "state": "disallowed"
+                }
+            ]
+		}
+	}
+]

services/git-bridge/src/test/resources/uk/ac/ic/wlgitbridge/WLGitBridgeIntegrationTest/pushSucceedsAfterRemovingInvalidFiles/invalidState/testproj/main.tex

@@ -0,0 +1 @@
+content

services/git-bridge/src/test/resources/uk/ac/ic/wlgitbridge/WLGitBridgeIntegrationTest/pushSucceedsAfterRemovingInvalidFiles/validState/state.json

@@ -0,0 +1,29 @@
+[
+	{
+		"project": "testproj",
+		"getDoc": {
+			"versionID": 1,
+			"createdAt": "2014-11-30T18:40:58.123Z",
+			"email": "test@example.com",
+			"name": "Test User"
+		},
+		"getSavedVers": [],
+		"getForVers": [
+			{
+				"versionID": 1,
+				"srcs": [
+                    {
+                    	"content": "content\n",
+                    	"path": "main.tex"
+                    }
+	            ],
+	            "atts": []
+	        }
+		],
+		"push": "success",
+	    "postback": {
+	   		"type": "success",
+			"versionID": 2
+	  	}
+	}
+]

services/git-bridge/src/test/resources/uk/ac/ic/wlgitbridge/WLGitBridgeIntegrationTest/pushSucceedsAfterRemovingInvalidFiles/validState/testproj/main.tex

@@ -0,0 +1 @@
+content