diff --git a/src/test/java/edu/ntnu/idi/idatt2003/g40/mappe/ExchangeTest.java b/src/test/java/edu/ntnu/idi/idatt2003/g40/mappe/ExchangeTest.java
index a06f463..9e11d44 100644
--- a/src/test/java/edu/ntnu/idi/idatt2003/g40/mappe/ExchangeTest.java
+++ b/src/test/java/edu/ntnu/idi/idatt2003/g40/mappe/ExchangeTest.java
@@ -1,3 +1,92 @@
-public class ExchangeTest {
-    
-}
+package edu.ntnu.idi.idatt2003.g40.mappe;
+
+import org.junit.jupiter.api.Test;
+
+import java.math.BigDecimal;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class ExchangeTest {
+
+    @Test
+    void constructorSetsNameWeekAndStocksCorrectly() {
+        Stock apple = new Stock("AAPL", "Apple", new BigDecimal("150"));
+        Stock tesla = new Stock("TSLA", "Tesla", new BigDecimal("200"));
+
+        Exchange exchange = new Exchange("NASDAQ", List.of(apple, tesla));
+
+        assertEquals("NASDAQ", exchange.getName());
+        assertEquals(1, exchange.getWeek());
+        assertTrue(exchange.hasStock("AAPL"));
+        assertTrue(exchange.hasStock("TSLA"));
+    }
+
+    @Test
+    void getStockReturnsCorrectStock() {
+        Stock apple = new Stock("AAPL", "Apple", new BigDecimal("150"));
+        Exchange exchange = new Exchange("NASDAQ", List.of(apple));
+
+        Stock result = exchange.getStock("AAPL");
+
+        assertSame(apple, result);
+    }
+
+    @Test
+    void findStocksReturnsMatchingStocksBySymbolOrCompany() {
+        Stock apple = new Stock("AAPL", "Apple", new BigDecimal("150"));
+        Stock tesla = new Stock("TSLA", "Tesla", new BigDecimal("200"));
+        Exchange exchange = new Exchange("NASDAQ", List.of(apple, tesla));
+
+        List<Stock> resultBySymbol = exchange.findStocks("AAP");
+        List<Stock> resultByCompany = exchange.findStocks("tes");
+
+        assertEquals(1, resultBySymbol.size());
+        assertTrue(resultBySymbol.contains(apple));
+
+        assertEquals(1, resultByCompany.size());
+        assertTrue(resultByCompany.contains(tesla));
+    }
+
+    @Test
+    void buyReturnsPurchaseAndWithdrawsMoneyFromPlayer() {
+        Stock apple = new Stock("AAPL", "Apple", new BigDecimal("100"));
+        Exchange exchange = new Exchange("NASDAQ", List.of(apple));
+        Player player = new Player("Alice", new BigDecimal("1000"));
+
+        Transaction transaction = exchange.buy("AAPL", new BigDecimal("2"), player);
+
+        assertInstanceOf(Purchase.class, transaction);
+        assertEquals(1, transaction.getWeek());
+        assertEquals(new BigDecimal("2"), transaction.getShare().getQuantity());
+        assertEquals(new BigDecimal("100"), transaction.getShare().getPurchasePrice());
+        assertEquals(new BigDecimal("799.000"), player.getMoney());
+    }
+
+    @Test
+    void sellReturnsSaleAndAddsMoneyToPlayer() {
+        Stock apple = new Stock("AAPL", "Apple", new BigDecimal("150"));
+        Exchange exchange = new Exchange("NASDAQ", List.of(apple));
+        Player player = new Player("Alice", new BigDecimal("1000"));
+        Share share = new Share(apple, new BigDecimal("2"), new BigDecimal("100"));
+
+        Transaction transaction = exchange.sell(share, player);
+
+        assertInstanceOf(Sale.class, transaction);
+        assertEquals(1, transaction.getWeek());
+        assertSame(share, transaction.getShare());
+        assertEquals(new BigDecimal("1267.9000"), player.getMoney());
+    }
+
+    @Test
+    void advanceIncreasesWeekAndUpdatesStockPrice() {
+        Stock apple = new Stock("AAPL", "Apple", new BigDecimal("100"));
+        Exchange exchange = new Exchange("NASDAQ", List.of(apple));
+
+        BigDecimal oldPrice = apple.getSalesPrice();
+        exchange.advance();
+
+        assertEquals(2, exchange.getWeek());
+        assertNotEquals(oldPrice, apple.getSalesPrice());
+    }
+}
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