Add task list command

docs/UserGuide.md

@@ -156,6 +156,22 @@ Examples:
 - `list` followed by `delete 2` deletes the 2nd person in the address book.
 - `find Betsy` followed by `delete 1` deletes the 1st person in the results of the `find` command.
 
+### Listing tasks: `task list`
+
+Lists all tasks in the task list. Clears any existing filters.
+
+**Format:**
+
+`task list`
+
+#### Filtering tasks
+
+Tasks can be filtered by completion status and/or tags. Show only completed tasks with `done/`, pending tasks with `undone/` and tasks with a certain tag `TAG` with `tag/TAG`.
+
+**Format:**
+
+`task list [done/] [undone/] [t/TAG]`
+
 ### Adding a task: `task add`
 
 Allows the user to add a task to the current database.
@@ -164,7 +180,7 @@ Each task has a compulsory title field, and textual description, timestamp, and
 
 **Format:**
 
-`task add TITLE [d/DESCRIPTION] [ts/TIMESTAMP] [t/TAG}`
+`task add TITLE [d/DESCRIPTION] [ts/TIMESTAMP] [t/TAG]`
 
 **Example:**
 

src/main/java/seedu/address/logic/commands/task/ListTaskCommand.java

@@ -0,0 +1,50 @@
+package seedu.address.logic.commands.task;
+
+import static java.util.Objects.requireNonNull;
+
+import java.util.List;
+
+import seedu.address.logic.commands.CommandResult;
+import seedu.address.logic.commands.TaskCommand;
+import seedu.address.logic.commands.exceptions.CommandException;
+import seedu.address.model.Model;
+import seedu.address.model.task.filters.TaskFilters.TaskFilter;
+
+/**
+ * Completes an existing task in the task list.
+ */
+public class ListTaskCommand extends TaskCommand {
+    public static final String COMMAND_WORD = "list";
+    public static final String FULL_COMMAND_WORD = TaskCommand.COMMAND_WORD + " " + COMMAND_WORD;
+    public static final String MESSAGE_SUCCESS = "Task list updated";
+    public static final String MESSAGE_USAGE = FULL_COMMAND_WORD
+            + ": Lists tasks matching the given search conditions.\n"
+            + "Parameters: t/TAG (tasks containing the tag TAG) "
+            + "Example: " + FULL_COMMAND_WORD + " 1";
+
+    private final List<TaskFilter> taskFilters;
+
+    public ListTaskCommand(List<TaskFilter> taskFilters) {
+        this.taskFilters = taskFilters;
+    }
+
+    @Override
+    public CommandResult execute(Model model) throws CommandException {
+        requireNonNull(model);
+
+        model.setTaskFilters(taskFilters);
+        return new CommandResult(MESSAGE_SUCCESS);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        return this == o
+                || (o instanceof ListTaskCommand
+                && taskFilters.equals(((ListTaskCommand) o).taskFilters));
+    }
+
+    @Override
+    public int hashCode() {
+        return taskFilters.hashCode();
+    }
+}

src/main/java/seedu/address/logic/parser/CliSyntax.java

@@ -16,4 +16,6 @@ public class CliSyntax {
     public static final Prefix PREFIX_DESCRIPTION = new Prefix("d/");
     public static final Prefix PREFIX_TIMESTAMP = new Prefix("ts/");
     public static final Prefix PREFIX_TITLE = new Prefix("ti/");
+    public static final Prefix PREFIX_DONE = new Prefix("done/");
+    public static final Prefix PREFIX_UNDONE = new Prefix("undone/");
 }

src/main/java/seedu/address/logic/parser/TaskCommandParser.java

@@ -12,12 +12,14 @@
 import seedu.address.logic.commands.task.DeleteTaskCommand;
 import seedu.address.logic.commands.task.DoneTaskCommand;
 import seedu.address.logic.commands.task.EditTaskCommand;
+import seedu.address.logic.commands.task.ListTaskCommand;
 import seedu.address.logic.commands.task.PurgeTaskCommand;
 import seedu.address.logic.parser.exceptions.ParseException;
 import seedu.address.logic.parser.task.AddTaskCommandParser;
 import seedu.address.logic.parser.task.DeleteTaskCommandParser;
 import seedu.address.logic.parser.task.DoneTaskCommandParser;
 import seedu.address.logic.parser.task.EditTaskCommandParser;
+import seedu.address.logic.parser.task.ListTaskCommandParser;
 
 /**
  * Parses all task-related commands (those starting with "task") and returns a TaskCommand.
@@ -50,6 +52,9 @@ public TaskCommand parse(String userInput) throws ParseException {
         case EditTaskCommand.COMMAND_WORD:
             return new EditTaskCommandParser().parse(arguments);
 
+        case ListTaskCommand.COMMAND_WORD:
+            return new ListTaskCommandParser().parse(arguments);
+
         case PurgeTaskCommand.COMMAND_WORD:
             return new PurgeTaskCommand();
 

src/main/java/seedu/address/logic/parser/task/ListTaskCommandParser.java

@@ -0,0 +1,44 @@
+package seedu.address.logic.parser.task;
+
+import static seedu.address.logic.parser.CliSyntax.PREFIX_DONE;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_TAG;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_UNDONE;
+
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import seedu.address.logic.commands.task.ListTaskCommand;
+import seedu.address.logic.parser.ArgumentMultimap;
+import seedu.address.logic.parser.ArgumentTokenizer;
+import seedu.address.logic.parser.Parser;
+import seedu.address.logic.parser.ParserUtil;
+import seedu.address.logic.parser.exceptions.ParseException;
+import seedu.address.model.tag.Tag;
+import seedu.address.model.task.filters.TaskFilters;
+import seedu.address.model.task.filters.TaskFilters.TaskFilter;
+
+public class ListTaskCommandParser implements Parser<ListTaskCommand> {
+    /**
+     * Parses the given {@code String} of arguments in the context of the EditTaskCommand
+     * and returns an EditTaskCommand object for execution.
+     * @throws ParseException if the user input does not conform the expected format
+     */
+    public ListTaskCommand parse(String args) throws ParseException {
+        ArgumentMultimap argMultimap =
+                ArgumentTokenizer.tokenize(args, PREFIX_DONE, PREFIX_UNDONE, PREFIX_TAG);
+
+        Set<Tag> tags = ParserUtil.parseTags(argMultimap.getAllValues(PREFIX_TAG));
+        List<TaskFilter> taskFilters = tags.stream().map(TaskFilters.FILTER_TAG).collect(Collectors.toList());
+
+        if (argMultimap.getValue(PREFIX_DONE).isPresent()) {
+            taskFilters.add(TaskFilters.FILTER_DONE);
+        }
+
+        if (argMultimap.getValue(PREFIX_UNDONE).isPresent()) {
+            taskFilters.add(TaskFilters.FILTER_DONE.invert());
+        }
+
+        return new ListTaskCommand(taskFilters);
+    }
+}

src/main/java/seedu/address/model/ModelManager.java

@@ -59,6 +59,16 @@ public ModelManager() {
         this(new AddressBook(), new TaskList(), new UserPrefs());
     }
 
+    /**
+     * Returns a new ModelManager initialize from the given {@link Model}.
+     * @param model The model to initialize the {@link ModelManager} from
+     * @return The initialized ModelManager
+     */
+    public static ModelManager from(Model model) {
+        return new ModelManager(
+                new AddressBook(model.getAddressBook()), new TaskList(model.getTaskList()) , new UserPrefs());
+    }
+
     //=========== UserPrefs ==================================================================================
 
     @Override

src/test/java/seedu/address/logic/commands/task/ListTaskCommandTest.java

@@ -0,0 +1,75 @@
+package seedu.address.logic.commands.task;
+
+import static seedu.address.logic.commands.CommandTestUtil.assertCommandSuccess;
+import static seedu.address.logic.commands.task.ListTaskCommand.MESSAGE_SUCCESS;
+import static seedu.address.testutil.TypicalPersons.getTypicalAddressBook;
+import static seedu.address.testutil.TypicalTasks.getTypicalTaskList;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+
+import seedu.address.logic.commands.Command;
+import seedu.address.model.Model;
+import seedu.address.model.ModelManager;
+import seedu.address.model.UserPrefs;
+import seedu.address.model.tag.Tag;
+import seedu.address.model.task.filters.TaskFilters;
+import seedu.address.model.task.filters.TaskFilters.TaskFilter;
+
+public class ListTaskCommandTest {
+    private final Model model = new ModelManager(getTypicalAddressBook(), getTypicalTaskList(), new UserPrefs());
+
+    @Test
+    void execute_noFilter_showsEntireList() {
+        Command command = new ListTaskCommand(new ArrayList<>());
+        Model expectedModel = ModelManager.from(model);
+        expectedModel.setTaskFilters(new ArrayList<>());
+
+        assertCommandSuccess(command, model, MESSAGE_SUCCESS, expectedModel);
+    }
+
+    @Test
+    void execute_tagsFilter_showsTasksWithTag() {
+        Tag tag = new Tag("important");
+        List<TaskFilter> taskFilters = List.of(TaskFilters.FILTER_TAG.apply(tag));
+        Command command = new ListTaskCommand(taskFilters);
+        Model expectedModel = ModelManager.from(model);
+        expectedModel.setTaskFilters(taskFilters);
+
+        assertCommandSuccess(command, model, MESSAGE_SUCCESS, expectedModel);
+    }
+
+    @Test
+    void execute_multipleFilters_showsCorrectTasks() {
+        Tag tag = new Tag("important");
+        List<TaskFilter> taskFilters = List.of(
+                TaskFilters.FILTER_TAG.apply(tag),
+                TaskFilters.FILTER_DONE
+        );
+        Command command = new ListTaskCommand(taskFilters);
+        Model expectedModel = ModelManager.from(model);
+        expectedModel.setTaskFilters(taskFilters);
+
+        assertCommandSuccess(command, model, MESSAGE_SUCCESS, expectedModel);
+    }
+
+    @Test
+    void execute_filterThenClear_showsAllTasks() {
+        Tag tag = new Tag("important");
+        List<TaskFilter> taskFilters = List.of(
+                TaskFilters.FILTER_TAG.apply(tag),
+                TaskFilters.FILTER_DONE
+        );
+        Command command = new ListTaskCommand(taskFilters);
+        Model expectedModel = ModelManager.from(model);
+
+        expectedModel.setTaskFilters(taskFilters);
+        assertCommandSuccess(command, model, MESSAGE_SUCCESS, expectedModel);
+
+        Command clearCommand = new ListTaskCommand(List.of());
+        expectedModel.setTaskFilters(List.of());
+        assertCommandSuccess(clearCommand, model, MESSAGE_SUCCESS, expectedModel);
+    }
+}

src/test/java/seedu/address/logic/parser/task/ListTaskCommandParserTest.java

@@ -0,0 +1,43 @@
+package seedu.address.logic.parser.task;
+
+import static seedu.address.logic.parser.CliSyntax.PREFIX_DONE;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_TAG;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_UNDONE;
+import static seedu.address.logic.parser.CommandParserTestUtil.assertParseSuccess;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+
+import seedu.address.logic.commands.task.ListTaskCommand;
+import seedu.address.model.tag.Tag;
+import seedu.address.model.task.filters.TaskFilters;
+import seedu.address.model.task.filters.TaskFilters.TaskFilter;
+
+public class ListTaskCommandParserTest {
+    private final ListTaskCommandParser parser = new ListTaskCommandParser();
+    @Test
+    void parse_emptyArguments_noTaskFilters() {
+        assertParseSuccess(parser, "", new ListTaskCommand(new ArrayList<>()));
+    }
+
+    @Test
+    void parse_showDone_showDoneTasks() {
+        assertParseSuccess(parser, " " + PREFIX_DONE, new ListTaskCommand(List.of(TaskFilters.FILTER_DONE)));
+    }
+
+    @Test
+    void parse_showUndone_showUndoneTasks() {
+        assertParseSuccess(parser, " " + PREFIX_UNDONE, new ListTaskCommand(List.of(TaskFilters.FILTER_DONE.invert())));
+    }
+
+    @Test
+    void parse_showTag_showTaggedTasks() {
+        String tagName = "important";
+        Tag tag = new Tag(tagName);
+        List<TaskFilter> taskFilters = List.of(TaskFilters.FILTER_TAG.apply(tag));
+        assertParseSuccess(parser, " " + PREFIX_TAG + tagName,
+                new ListTaskCommand(taskFilters));
+    }
+}

src/test/java/seedu/address/testutil/TypicalTasks.java

@@ -10,7 +10,19 @@
 public class TypicalTasks {
     public static final Task BUY_GROCERIES = new TaskBuilder().build();
     public static final Task DO_HOMEWORK = new TaskBuilder()
-            .withTitle("Do homework").withDescription("Math, physics and chemistry").build();
+            .withTitle("Do homework")
+            .withDescription("Math, physics and chemistry")
+            .withTags("important", "homework")
+            .build();
+    public static final Task CLEAN_ROOM = new TaskBuilder()
+            .withTitle("Clean my room")
+            .withTags("important")
+            .build();
+    public static final Task ARRANGE_MEETING = new TaskBuilder()
+            .withTitle("Arrange meeting")
+            .withTags("work", "important")
+            .withDone(true)
+            .build();
 
     /**
      * Returns an {@code AddressBook} with all the typical tasks.
@@ -24,6 +36,11 @@ public static TaskList getTypicalTaskList() {
     }
 
     public static List<Task> getTypicalTasks() {
-        return new ArrayList<>(Arrays.asList(BUY_GROCERIES, DO_HOMEWORK));
+        return new ArrayList<>(Arrays.asList(
+                BUY_GROCERIES,
+                DO_HOMEWORK,
+                CLEAN_ROOM,
+                ARRANGE_MEETING
+        ));
     }
 }