Merge pull request #30 from Chinorea/JUnit-Test

Add JUnit test for DisplayExpense Feature

src/main/java/seedu/budgetbuddy/commands/DisplayExpenseCommand.java

@@ -1,5 +1,6 @@
 package seedu.budgetbuddy.commands;
 
+import seedu.budgetbuddy.Ui;
 import seedu.budgetbuddy.transaction.expense.Category;
 import seedu.budgetbuddy.transaction.expense.ExpenseManager;
 
@@ -56,6 +57,14 @@ public static boolean isCommand(String command) {
         return command.startsWith("display expenses");
     }
 
+    public Category getCategory() {
+        return category;
+    }
+
+    public YearMonth getMonth() {
+        return month;
+    }
+
     /**
      * Executes the command to list all expenses by invoking the ExpenseManager's method.
      */
@@ -64,11 +73,11 @@ public void execute() {
         if (category == null && month == null) {
             ExpenseManager.listExpenses();
         } else if (category == null){
-            ExpenseManager.displayExpensesWithDate(month);
+            Ui.displayToUser(ExpenseManager.displayExpensesWithDate(month));
         } else if (month == null) {
-            ExpenseManager.displayExpensesWithCategory(category);
+            Ui.displayToUser(ExpenseManager.displayExpensesWithCategory(category));
         } else {
-            ExpenseManager.displayExpensesWithCategoryAndDate(category,month);
+            Ui.displayToUser(ExpenseManager.displayExpensesWithCategoryAndDate(category,month));
         }
     }
 

src/main/java/seedu/budgetbuddy/transaction/expense/ExpenseManager.java

@@ -75,8 +75,9 @@ public static void listExpenses() {
      * Displays each expense with its corresponding number.
      * @param category
      * @param month
+     * @return result String to be displayed to user
      */
-    public static void displayExpensesWithCategoryAndDate(Category category, YearMonth month) {
+    public static String displayExpensesWithCategoryAndDate(Category category, YearMonth month) {
         String result = "";
         int counter = 1;
         for (Expense expense : expenses) {
@@ -88,15 +89,16 @@ public static void displayExpensesWithCategoryAndDate(Category category, YearMon
         if(result.equals("")) {
             result = getEmptyDisplayMessage();
         }
-        Ui.displayToUser(result);
+        return result;
     }
 
     /**
      * Display all expense that matches with category field
      * Displays each expense with its corresponding number.
      * @param category
+     * @return result String to be displayed to user
      */
-    public static void displayExpensesWithCategory(Category category) {
+    public static String displayExpensesWithCategory(Category category) {
         String result = "";
         int counter = 1;
         for (Expense expense : expenses) {
@@ -108,15 +110,16 @@ public static void displayExpensesWithCategory(Category category) {
         if(result.equals("")) {
             result = getEmptyDisplayMessage();
         }
-        Ui.displayToUser(result);
+        return result;
     }
 
     /**
      * Display all expense that matches with month field
      * Displays each expense with its corresponding number.
      * @param month
+     * @return result String to be displayed to user
      */
-    public static void displayExpensesWithDate(YearMonth month) {
+    public static String displayExpensesWithDate(YearMonth month) {
         String result = "";
         int counter = 1;
         for (Expense expense : expenses) {
@@ -128,7 +131,7 @@ public static void displayExpensesWithDate(YearMonth month) {
         if(result.equals("")) {
             result = getEmptyDisplayMessage();
         }
-        Ui.displayToUser(result);
+        return result;
     }
 
     /**

src/test/java/seedu/budgetbuddy/transaction/expense/ExpenseManagerTest.java

@@ -0,0 +1,62 @@
+package seedu.budgetbuddy.transaction.expense;
+
+import org.junit.jupiter.api.Test;
+
+import java.time.LocalDate;
+import java.time.YearMonth;
+import java.util.ArrayList;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+class ExpenseManagerTest {
+
+    private static int numberOfExpenses = 0;
+    private static ArrayList<Expense> expenses = new ArrayList<>();
+    private static ExpenseManager expenseManager;
+    private static final String EMPTY_DISPLAY_STRING =
+            "No expense entry with given parameters found, try again with a different parameter.";
+
+    void initializeTestContent(){
+        expenseManager = new ExpenseManager(expenses, numberOfExpenses);
+        Expense newExpense = new Expense("New Food",
+                12,
+                LocalDate.parse("2024-02-12"),
+                Category.FOOD);
+        expenseManager.addExpense(newExpense);
+    }
+
+    String getExpectedString(){
+        String result = "";
+        int counter = 1;
+        for (Expense expense : ExpenseManager.getExpenses()) {
+            result += counter + ". " + expense.toString() + "\n";
+            counter++;
+        }
+        return result;
+    }
+
+    @Test
+    void displayExpensesWithCategoryAndDate_validMonthCategory_expectOneEntry() {
+        initializeTestContent();
+        Category category = Category.FOOD;
+        YearMonth yearMonth = YearMonth.of(2024, 2);
+        assertEquals(getExpectedString(),
+                ExpenseManager.displayExpensesWithCategoryAndDate(category, yearMonth));
+    }
+
+    @Test
+    void displayExpensesWithCategoryAndDate_incorrectCategory_expectEmptyDisplayString() {
+        Category category = Category.TRANSPORT;
+        YearMonth yearMonth = YearMonth.of(2024, 2);
+        assertEquals(EMPTY_DISPLAY_STRING,
+                ExpenseManager.displayExpensesWithCategoryAndDate(category, yearMonth));
+    }
+
+    @Test
+    void displayExpensesWithCategoryAndDate_incorrectMonth_expectEmptyDisplayString() {
+        Category category = Category.FOOD;
+        YearMonth yearMonth = YearMonth.of(2024, 1);
+        assertEquals(EMPTY_DISPLAY_STRING,
+                ExpenseManager.displayExpensesWithCategoryAndDate(category, yearMonth));
+    }
+}

src/test/java/seedu/budgetbuddy/validators/DisplayExpenseValidatorTest.java

@@ -0,0 +1,42 @@
+package seedu.budgetbuddy.validators;
+
+import org.junit.jupiter.api.Test;
+import seedu.budgetbuddy.commands.DisplayExpenseCommand;
+import seedu.budgetbuddy.transaction.expense.Category;
+import java.time.YearMonth;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static seedu.budgetbuddy.validators.DateValidator.validateYearMonth;
+
+class DisplayExpenseValidatorTest {
+
+    @Test
+    void checkDisplayType_categoryIsEmpty_expectNullCategory(){
+        DisplayExpenseValidator expenseValidator = new DisplayExpenseValidator();
+        Category category = null;
+        YearMonth yearMonth = validateYearMonth("02/2024");
+        DisplayExpenseCommand command = (DisplayExpenseCommand) expenseValidator.checkDisplayType(category, yearMonth);
+        assertEquals(null, command.getCategory());
+        assertEquals(yearMonth,command.getMonth());
+    }
+
+    @Test
+    void checkDisplayType_monthIsEmpty_expectNullMonth(){
+        DisplayExpenseValidator expenseValidator = new DisplayExpenseValidator();
+        Category category = Category.FOOD;
+        YearMonth yearMonth = null;
+        DisplayExpenseCommand command = (DisplayExpenseCommand) expenseValidator.checkDisplayType(category, yearMonth);
+        assertEquals(category, command.getCategory());
+        assertEquals(yearMonth,command.getMonth());
+    }
+
+    @Test
+    void checkDisplayType_categoryMonthSpecified_expectSameValues(){
+        DisplayExpenseValidator expenseValidator = new DisplayExpenseValidator();
+        Category category = Category.FOOD;
+        YearMonth yearMonth = validateYearMonth("02/2024");
+        DisplayExpenseCommand command = (DisplayExpenseCommand) expenseValidator.checkDisplayType(category, yearMonth);
+        assertEquals(category, command.getCategory());
+        assertEquals(yearMonth,command.getMonth());
+    }
+}