test(cxx): add more test cases

template/cxx/{{cookiecutter.project_slug}}/include/my_lib.h

@@ -1,4 +1,9 @@
 #pragma once
 
+#include <limits>
+#include <stdexcept>
+
 int add(int a, int b);
 int sub(int a, int b);
+int mul(int a, int b);
+double divide(double a, double b);

template/cxx/{{cookiecutter.project_slug}}/src/main.cpp

@@ -7,5 +7,7 @@ int main()
     say_hi();
     std::cout << "add(1, 2) = " << add(1, 2) << std::endl;
     std::cout << "sub(1, 2) = " << sub(1, 2) << std::endl;
+    std::cout << "mul(1, 2) = " << mul(1, 2) << std::endl;
+    std::cout << "divide(1, 2) = " << divide(1, 2) << std::endl;
     return 0;
 }

template/cxx/{{cookiecutter.project_slug}}/src/my_lib.cpp

@@ -9,3 +9,17 @@ int sub(const int a, const int b)
 {
     return a - b;
 }
+
+int mul(const int a, const int b)
+{
+    return a * b;
+}
+
+double divide(const double a, const double b)
+{
+    if (b == 0.0)
+    {
+        throw std::invalid_argument("Division by zero");
+    }
+    return a / b;
+}

template/cxx/{{cookiecutter.project_slug}}/tests/test_my_lib.cpp

@@ -1,26 +1,73 @@
 #include "gtest/gtest.h"
 #include "my_lib.h"
 
-TEST(AddTest, PositiveNumbers)
+// Group: Add Function Tests
+TEST(AddTest, HandlesZeroInputs)
+{
+    EXPECT_EQ(add(0, 0), 0);
+}
+
+TEST(AddTest, HandlesPositiveInputs)
 {
     EXPECT_EQ(add(1, 2), 3);
     EXPECT_EQ(add(10, 5), 15);
 }
 
-TEST(AddTest, NegativeNumbers)
+TEST(AddTest, HandlesNegativeInputs)
 {
     EXPECT_EQ(add(-1, -2), -3);
     EXPECT_EQ(add(-5, 5), 0);
 }
 
-TEST(SubTest, PositiveNumbers)
+// Group: Subtract Function Tests
+TEST(SubtractTest, HandlesZeroInputs)
+{
+    EXPECT_EQ(sub(0, 0), 0);
+}
+
+TEST(SubtractTest, HandlesPositiveInputs)
 {
     EXPECT_EQ(sub(10, 5), 5);
     EXPECT_EQ(sub(5, 10), -5);
 }
 
-TEST(SubTest, NegativeNumbers)
+TEST(SubtractTest, HandlesNegativeInputs)
 {
     EXPECT_EQ(sub(-10, -5), -5);
     EXPECT_EQ(sub(-5, -10), 5);
 }
+
+// Group: Multiply Function Tests
+TEST(MultiplyTest, HandlesZeroInputs)
+{
+    EXPECT_EQ(mul(0, 0), 0);
+}
+
+TEST(MultiplyTest, HandlesPositiveInputs)
+{
+    EXPECT_EQ(mul(2, 3), 6);
+    EXPECT_EQ(mul(6, 3), 18);
+}
+
+TEST(MultiplyTest, HandlesNegativeInputs)
+{
+    EXPECT_EQ(mul(-2, -3), 6);
+    EXPECT_EQ(mul(-2, 3), -6);
+}
+
+// Group: Divide Function Tests
+TEST(DivideTest, HandlesZeroDivision)
+{
+    EXPECT_THROW(divide(10.0, 0.0), std::invalid_argument);
+}
+
+TEST(DivideTest, HandlesPositiveInputs)
+{
+    EXPECT_NEAR(divide(10.0, 3.0), 3.33333, 1e-5);
+    EXPECT_NEAR(divide(10.0, 2.0), 5.0, 1e-5);
+}
+
+TEST(DivideTest, HandlesNegativeInputs)
+{
+    EXPECT_NEAR(divide(-10.0, 2.0), -5.0, 1e-5);
+}