Add test class ParserTest.java, update Parser.java and DukeException.…

…java

src/main/java/duke/DukeException.java

@@ -10,6 +10,14 @@ public class DukeException extends Exception {
     public static final DukeException INVALID_TASK_DESCRIPTION_EXCEPTION = new DukeException(
             "Sorry, the description of a task cannot be empty.");
 
+    public static final DukeException INVALID_DEADLINE_FORMAT_EXCEPTION = new DukeException(
+            "Sorry, the description of a Deadline must be in this format:\n" +
+                    "\tdeadline [task name] /by [deadline]");
+
+    public static final DukeException INVALID_EVENT_FORMAT_EXCEPTION = new DukeException(
+            "Sorry, the description of an Event must be in this format:\n" +
+                    "\tevent [task name] /at [time]");
+
     public static final DukeException FILE_PARSING_EXCEPTION = new DukeException(
             "Sorry, an error occurred while trying to parse the file.");
 

src/main/java/duke/Parser.java

@@ -53,23 +53,31 @@ public static Command parse(String string) throws DukeException {
                 break;
             case "todo":
                 if (parsingScanner.hasNext()) {
-                    command = new AddCommand(CommandType.TODO, parsingScanner.nextLine());
+                    command = new AddCommand(CommandType.TODO, parsingScanner.nextLine().trim());
                 } else {
                     throw DukeException.INVALID_TASK_DESCRIPTION_EXCEPTION;
                 }
                 break;
             case "deadline":
                 if (parsingScanner.hasNext()) {
-                    command = new AddCommand(CommandType.DEADLINE,
-                            parsingScanner.nextLine().split("( /by )", 2));
+                    try {
+                        String[] details = parsingScanner.nextLine().trim().split("( /by )", 2);
+                        command = new AddCommand(CommandType.DEADLINE, details[0], details[1]);
+                    } catch (IndexOutOfBoundsException e) {
+                        throw DukeException.INVALID_DEADLINE_FORMAT_EXCEPTION;
+                    }
                 } else {
                     throw DukeException.INVALID_TASK_DESCRIPTION_EXCEPTION;
                 }
                 break;
             case "event":
                 if (parsingScanner.hasNext()) {
-                    command = new AddCommand(CommandType.EVENT,
-                            parsingScanner.nextLine().split("( /at )", 2));
+                    try {
+                        String[] details = parsingScanner.nextLine().trim().split("( /at )", 2);
+                        command = new AddCommand(CommandType.EVENT, details[0], details[1]);
+                    } catch (IndexOutOfBoundsException e) {
+                        throw DukeException.INVALID_EVENT_FORMAT_EXCEPTION;
+                    }
                 } else {
                     throw DukeException.INVALID_TASK_DESCRIPTION_EXCEPTION;
                 }

src/test/java/duke/ParserTest.java

@@ -0,0 +1,161 @@
+package duke;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.fail;
+
+public class ParserTest {
+    @Test
+    public void parse_bye_bye() throws Exception {
+        assertEquals("BYE", Parser.parse("bye").toString());
+    }
+
+    @Test
+    public void parse_list_list() throws Exception {
+        assertEquals("LIST", Parser.parse("list").toString());
+    }
+
+    @Test
+    public void parse_done1_done1() throws Exception {
+        assertEquals("DONE 1", Parser.parse("done 1").toString());
+    }
+
+    @Test
+    public void parse_delete2_delete2() throws Exception {
+        assertEquals("DELETE 2", Parser.parse("delete 2").toString());
+    }
+
+    @Test
+    public void parse_todo_todo() throws Exception {
+        assertEquals("TODO [read book]", Parser.parse("todo read book").toString());
+    }
+
+    @Test
+    public void parse_deadline_deadline() throws Exception {
+        assertEquals("DEADLINE [return book, 6th June 2020]",
+                Parser.parse("deadline return book /by 6th June 2020").toString());
+    }
+
+    @Test
+    public void parse_event_event() throws Exception {
+        assertEquals("EVENT [meeting, time]",
+                Parser.parse("event meeting /at time").toString());
+    }
+
+    @Test
+    public void parse_caseInsensitive_success() throws Exception {
+        assertEquals("DEADLINE [case, insensitive]",
+                Parser.parse("dEaDlInE case /by insensitive").toString());
+    }
+
+    @Test
+    public void parse_doneBadInteger_exceptionThrown() {
+        try {
+            assertEquals("DONE 3", Parser.parse("done three").toString());
+            fail();
+        } catch (Exception e) {
+            assertEquals("Sorry, that is not a valid task.", e.getMessage());
+        }
+    }
+
+    @Test
+    public void parse_deleteNoNextScannerToken_exceptionThrown() {
+        try {
+            assertEquals("DELETE", Parser.parse("delete").toString());
+            fail();
+        } catch (Exception e) {
+            assertEquals("Sorry, that is not a valid task.", e.getMessage());
+        }
+    }
+
+    @Test
+    public void parse_todoNoNextScannerToken_exceptionThrown() {
+        try {
+            assertEquals("TODO", Parser.parse("todo").toString());
+            fail();
+        } catch (Exception e) {
+            assertEquals("Sorry, the description of a task cannot be empty.", e.getMessage());
+        }
+    }
+
+    @Test
+    public void parse_deadlineNoNextScannerToken_exceptionThrown() {
+        try {
+            assertEquals("DEADLINE", Parser.parse("deadline").toString());
+            fail();
+        } catch (Exception e) {
+            assertEquals("Sorry, the description of a task cannot be empty.", e.getMessage());
+        }
+    }
+
+    @Test
+    public void parse_deadlineNoBySubstring_exceptionThrown() {
+        try {
+            assertEquals("DEADLINE [do this, tonight]",
+                    Parser.parse("deadline do this tonight").toString());
+            fail();
+        } catch (Exception e) {
+            assertEquals("Sorry, the description of a Deadline must be in this format:\n" +
+                    "\tdeadline [task name] /by [deadline]", e.getMessage());
+        }
+    }
+
+    @Test
+    public void parse_deadlineWrongBySubstring_exceptionThrown() {
+        try {
+            assertEquals("DEADLINE [do this, tonight]",
+                    Parser.parse("deadline do this by tonight").toString());
+            fail();
+        } catch (Exception e) {
+            assertEquals("Sorry, the description of a Deadline must be in this format:\n" +
+                    "\tdeadline [task name] /by [deadline]", e.getMessage());
+        }
+    }
+
+    @Test
+    public void parse_deadlineFakeBySubstring_success() throws Exception {
+        assertEquals("DEADLINE [swing by Mom's, tomorrow]",
+                Parser.parse("deadline swing by Mom's /by tomorrow").toString());
+    }
+
+    @Test
+    public void parse_eventNoNextScannerToken_exceptionThrown() {
+        try {
+            assertEquals("EVENT", Parser.parse("event").toString());
+            fail();
+        } catch (Exception e) {
+            assertEquals("Sorry, the description of a task cannot be empty.", e.getMessage());
+        }
+    }
+
+    @Test
+    public void parse_eventNoAtSubstring_exceptionThrown() {
+        try {
+            assertEquals("EVENT [do this, 6pm]",
+                    Parser.parse("event do this 6pm").toString());
+            fail();
+        } catch (Exception e) {
+            assertEquals("Sorry, the description of an Event must be in this format:\n" +
+                    "\tevent [task name] /at [time]", e.getMessage());
+        }
+    }
+
+    @Test
+    public void parse_eventWrongAtSubstring_exceptionThrown() {
+        try {
+            assertEquals("EVENT [do this, 6pm]",
+                    Parser.parse("event do this at 6pm").toString());
+            fail();
+        } catch (Exception e) {
+            assertEquals("Sorry, the description of an Event must be in this format:\n" +
+                    "\tevent [task name] /at [time]", e.getMessage());
+        }
+    }
+
+    @Test
+    public void parse_eventFakeAtSubstring_success() throws Exception {
+        assertEquals("EVENT [stay at home, all times]",
+                Parser.parse("event stay at home /at all times").toString());
+    }
+}