feat: kata/simple-calculator

Author: ParanoidUser

kata/8-kyu/simple-calculator/README.md

@@ -1,39 +1,19 @@
-# [simple calculator ](https://www.codewars.com/kata/simple-calculator "https://www.codewars.com/kata/5810085c533d69f4980001cf")
+# [Simple calculator ](https://www.codewars.com/kata/simple-calculator "https://www.codewars.com/kata/5810085c533d69f4980001cf")
 
 You are required to create a simple calculator that returns the result of addition, subtraction, multiplication or division of two numbers.
 
-Your function will accept three arguments:<br>
-The first and second argument should be numbers.<br>
-The third argument should represent a sign indicating the operation to perform on these two numbers.
-```if-not:csharp,java
-if the variables are not numbers or the sign does not belong to the list above a message "unknown value" must be returned.
-```
-```if:csharp,java
+Your function will accept three arguments:  
+ - The first and second argument should be numbers.  
+- The third argument should represent a sign indicating the operation to perform on these two numbers.
+
 If the sign is not a valid sign, throw an IllegalArgumentException (Java) or ArgumentException (C#).
-```
 
 # Example:
 
-~~~if-not:csharp,java
-```
-arguments: 1, 2, "+"
-should return 3
-
-arguments: 1, 2, "&"
-should return "unknown value"
-
-arguments: 1, "k", "*"
-should return "unknown value"
-```
-~~~
-~~~if:csharp,java
 ```
 arguments: 1, 2, "+"
 should return 3
 
 arguments: 1, 2, "&"
 should throw an IllegalArgumentException (Java) or ArgumentException (C#)
-```
-~~~
-
-Good luck!
+```

kata/8-kyu/simple-calculator/main/Calculator.java

@@ -0,0 +1,11 @@
+interface Calculator {
+  static double calculate(double a, double b, String op) {
+    return switch (op) {
+      case "+" -> a + b;
+      case "-" -> a - b;
+      case "*" -> a * b;
+      case "/" -> b != 0 ? a / b : 0;
+      default -> throw new IllegalArgumentException();
+    };
+  }
+}

kata/8-kyu/simple-calculator/test/SolutionTest.java

@@ -0,0 +1,30 @@
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+class SolutionTest {
+  @ParameterizedTest
+  @CsvSource(textBlock = """
+      1, 2, +, 3
+      6, 2, +, 8
+      4, 3, -, 1
+      5, 5, *, 25
+      5, 4, /, 1.25
+      """)
+  void basicOperation(double a, double b, String op, double expected) {
+    assertEquals(expected, Calculator.calculate(a, b, op), 1e-3);
+  }
+
+  @ParameterizedTest
+  @CsvSource(textBlock = """
+      6, 2, &
+      3, 5, \\
+      5, 5, =
+      6, 3, '\t'
+      """)
+  void unsupportedOperation(double a, double b, String op) {
+    assertThrows(IllegalArgumentException.class, () -> Calculator.calculate(a, b, op));
+  }
+}