NoIssue: Add two tests for random Strings

src/test/java/com/r35157/libs/random/tests/sad/IncorrectRandomStringTests.java

@@ -0,0 +1,54 @@
+package com.r35157.libs.random.tests.sad;
+
+import com.r35157.libs.random.RandomValueGeneratorInt;
+import com.r35157.libs.random.RandomValueGeneratorString;
+import com.r35157.libs.random.impl.ref.RandomValueGeneratorIntImpl;
+import com.r35157.libs.random.impl.ref.RandomValueGeneratorStringImpl;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+@DisplayName("Sad Random Strings Tests")
+public class IncorrectRandomStringTests {
+
+    @DisplayName("Do initializing with <null> throw NPE?")
+    @Test
+    void testThatInitializingWithNullIntGeneratorThrows() {
+        // Arrange
+        String expectedErrorMsg = "Cannot initialize with <null> RandomValueGeneratorInt!";
+        RandomValueGeneratorInt rvgi = null;
+
+        // Act + Assert
+        NullPointerException thrown = assertThrows(
+                NullPointerException.class,
+                () -> new RandomValueGeneratorStringImpl(rvgi)
+        );
+
+        // Assert
+        String actualErrorMsg = thrown.getMessage();
+        assertEquals(expectedErrorMsg, actualErrorMsg);
+    }
+
+    @DisplayName("Do generating negative length Strings throw IAE?")
+    @Test
+    void testThatGeneratingStringsOfNegativeLengthThrowsIAE() {
+        // Arrange
+        int length = -1;
+        String expectedErrorMsg = "Cannot generate random Strings of size " + length + "!";
+        RandomValueGeneratorString sut = new RandomValueGeneratorStringImpl(rvgi);
+
+        // Act + Assert
+        IllegalArgumentException thrown = assertThrows(
+                IllegalArgumentException.class,
+                () -> sut.getSomeStringAlphaNumericOnly(length)
+        );
+
+        // Assert
+        String actualErrorMsg = thrown.getMessage();
+        assertEquals(expectedErrorMsg, actualErrorMsg);
+    }
+
+    private static final RandomValueGeneratorInt rvgi = new RandomValueGeneratorIntImpl();
+}