Increase BaseUtil coverage

src/main/java/com/adventofcode/flashk/common/BaseUtil.java

@@ -38,7 +38,7 @@ public static String hexToBinary(String hex) {
 	}
 
 	/**
-	 * Converts from hexadecimal to binary adding zero padding at the leading.
+	 * Converts from hexadecimal to binary and adds zero padding at the leading.
 	 * <p>
 	 * Any hexadecimal number can be represented with 4 binary digits (<code>6 hex = 0110 bin</code>).
 	 * </p>
@@ -53,12 +53,13 @@ public static String hexToBinary(String hex) {
 	 * 	BaseUtil.hexToBinaryPadLeft("6") = "0110"
 	 * </pre>
 	 * @param hex the hexadecimal code
-	 * @return the translated binary code
+	 * @return the translated binary code, it will always have a multiple of 4 digits.
 	 * @see #hexToBinary(String)
 	 */
 	public static String hexToBinaryPadLeft(String hex) {
 	    String unpaddedBinary = BaseUtil.hexToBinary(hex);
 	    int size = hex.length() * 4;
-	    return String.format("%"+size+"s", unpaddedBinary).replace(" ", "0");
+		String formatSize = "%" + size + "s";
+	    return String.format(formatSize, unpaddedBinary).replace(" ", "0");
 	}
 }

src/test/java/com/adventofcode/flashk/common/BaseUtilTest.java

@@ -0,0 +1,62 @@
+package com.adventofcode.flashk.common;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class BaseUtilTest {
+
+    @Test
+    void binaryToDecIntegerTest() {
+        assertEquals(0, BaseUtil.binaryToDecInteger("0"));
+        assertEquals(1, BaseUtil.binaryToDecInteger("1"));
+        assertEquals(2, BaseUtil.binaryToDecInteger("10"));
+        assertEquals(5, BaseUtil.binaryToDecInteger("101"));
+        assertEquals(8, BaseUtil.binaryToDecInteger("1000"));
+        assertEquals(10, BaseUtil.binaryToDecInteger("1010"));
+        assertEquals(15, BaseUtil.binaryToDecInteger("1111"));
+    }
+
+    @Test
+    void binaryToDecTest() {
+        assertEquals(0, BaseUtil.binaryToDec("0"));
+        assertEquals(1, BaseUtil.binaryToDec("1"));
+        assertEquals(2, BaseUtil.binaryToDec("10"));
+        assertEquals(5, BaseUtil.binaryToDec("101"));
+        assertEquals(8, BaseUtil.binaryToDec("1000"));
+        assertEquals(10, BaseUtil.binaryToDec("1010"));
+        assertEquals(15, BaseUtil.binaryToDec("1111"));
+    }
+
+    @Test
+    void hexToBinaryTest() {
+        assertEquals("0", BaseUtil.hexToBinary("0"));
+        assertEquals("1", BaseUtil.hexToBinary("1"));
+        assertEquals("10", BaseUtil.hexToBinary("2"));
+        assertEquals("101", BaseUtil.hexToBinary("5"));
+        assertEquals("1000", BaseUtil.hexToBinary("8"));
+        assertEquals("1010", BaseUtil.hexToBinary("A"));
+        assertEquals("1011", BaseUtil.hexToBinary("B"));
+        assertEquals("1100", BaseUtil.hexToBinary("C"));
+        assertEquals("1101", BaseUtil.hexToBinary("D"));
+        assertEquals("1110", BaseUtil.hexToBinary("E"));
+        assertEquals("1111", BaseUtil.hexToBinary("F"));
+        assertEquals("100110110", BaseUtil.hexToBinary("136"));
+    }
+
+    @Test
+    void hexToBinaryPadLeft() {
+        assertEquals("0000", BaseUtil.hexToBinaryPadLeft("0"));
+        assertEquals("0001", BaseUtil.hexToBinaryPadLeft("1"));
+        assertEquals("0010", BaseUtil.hexToBinaryPadLeft("2"));
+        assertEquals("0101", BaseUtil.hexToBinaryPadLeft("5"));
+        assertEquals("1000", BaseUtil.hexToBinaryPadLeft("8"));
+        assertEquals("1010", BaseUtil.hexToBinaryPadLeft("A"));
+        assertEquals("1011", BaseUtil.hexToBinaryPadLeft("B"));
+        assertEquals("1100", BaseUtil.hexToBinaryPadLeft("C"));
+        assertEquals("1101", BaseUtil.hexToBinaryPadLeft("D"));
+        assertEquals("1110", BaseUtil.hexToBinaryPadLeft("E"));
+        assertEquals("1111", BaseUtil.hexToBinaryPadLeft("F"));
+        assertEquals("000100110110", BaseUtil.hexToBinaryPadLeft("136"));
+    }
+}