feat: add token source position tracking to lexer

src/core/calculator.py

@@ -0,0 +1,20 @@
+class Calculator:
+    """A simple calculator class for basic arithmetic operations."""
+
+    def add(self, a, b):
+        """Add two numbers."""
+        return a + b
+
+    def subtract(self, a, b):
+        """Subtract b from a."""
+        return a - b
+
+    def multiply(self, a, b):
+        """Multiply two numbers."""
+        return a * b
+
+    def divide(self, a, b):
+        """Divide a by b."""
+        if b == 0:
+            raise ValueError("Cannot divide by zero")
+        return a / b

tests/test_calculator.py

@@ -0,0 +1,31 @@
+import pytest
+from src.core.calculator import Calculator
+
+
+class TestCalculator:
+    def setup_method(self):
+        self.calc = Calculator()
+
+    def test_add(self):
+        assert self.calc.add(2, 3) == 5
+        assert self.calc.add(-1, 1) == 0
+        assert self.calc.add(0, 0) == 0
+
+    def test_subtract(self):
+        assert self.calc.subtract(5, 3) == 2
+        assert self.calc.subtract(1, 1) == 0
+        assert self.calc.subtract(-1, -1) == 0
+
+    def test_multiply(self):
+        assert self.calc.multiply(3, 4) == 12
+        assert self.calc.multiply(-2, 3) == -6
+        assert self.calc.multiply(0, 5) == 0
+
+    def test_divide(self):
+        assert self.calc.divide(10, 2) == 5
+        assert self.calc.divide(7, 2) == 3.5
+        assert self.calc.divide(-6, 3) == -2
+
+    def test_divide_by_zero(self):
+        with pytest.raises(ValueError, match="Cannot divide by zero"):
+            self.calc.divide(5, 0)