package seedu.tache.testutil;

import seedu.tache.model.tag.UniqueTagList;
import seedu.tache.model.task.Name;
import seedu.tache.model.task.ReadOnlyTask;

/**
 * A mutable task object. For testing only.
 */
public class TestTask implements ReadOnlyTask {

    private Name name;
    private UniqueTagList tags;

    public TestTask() {
        tags = new UniqueTagList();
    }

    /**
     * Creates a copy of {@code taskToCopy}.
     */
    public TestTask(TestTask taskToCopy) {
        this.name = taskToCopy.getName();
        this.tags = taskToCopy.getTags();
    }

    public void setName(Name name) {
        this.name = name;
    }

    public void setTags(UniqueTagList tags) {
        this.tags = tags;
    }

    @Override
    public Name getName() {
        return name;
    }

    @Override
    public UniqueTagList getTags() {
        return tags;
    }

    @Override
    public String toString() {
        return getAsText();
    }

    public String getAddCommand() {
        StringBuilder sb = new StringBuilder();
        sb.append("add " + this.getName().fullName + " ");
        this.getTags().asObservableList().stream().forEach(s -> sb.append(";" + s.tagName + " "));
        return sb.toString();
    }
}

package seedu.tache.testutil;

import seedu.tache.model.tag.UniqueTagList;
import seedu.tache.model.task.Name;
import seedu.tache.model.task.ReadOnlyTask;

/**
 * A mutable task object. For testing only.
 */
public class TestTask implements ReadOnlyTask {

    private Name name;
    private UniqueTagList tags;

    public TestTask() {
        tags = new UniqueTagList();
    }

    /**
     * Creates a copy of {@code taskToCopy}.
     */
    public TestTask(TestTask taskToCopy) {
        this.name = taskToCopy.getName();
        this.tags = taskToCopy.getTags();
    }

    public void setName(Name name) {
        this.name = name;
    }

    public void setTags(UniqueTagList tags) {
        this.tags = tags;
    }

    @Override
    public Name getName() {
        return name;
    }

    @Override
    public UniqueTagList getTags() {
        return tags;
    }

    @Override
    public String toString() {
        return getAsText();
    }

    public String getAddCommand() {
        StringBuilder sb = new StringBuilder();
        sb.append("add " + this.getName().fullName + " ");
        this.getTags().asObservableList().stream().forEach(s -> sb.append("t/" + s.tagName + " "));
        return sb.toString();
    }
}

--- 
+++ 
@@ -50,7 +50,7 @@
     public String getAddCommand() {
         StringBuilder sb = new StringBuilder();
         sb.append("add " + this.getName().fullName + " ");
-        this.getTags().asObservableList().stream().forEach(s -> sb.append("t/" + s.tagName + " "));
+        this.getTags().asObservableList().stream().forEach(s -> sb.append(";" + s.tagName + " "));
         return sb.toString();
     }
 }
Update test case to match new AddCommand syntax
