bites 159

Author: [email protected]

.gitignore

@@ -50,3 +50,4 @@
 /113/README.md
 /119/README.md
 /111/README.md
+/159/README.md

159/calculator.py

@@ -0,0 +1,33 @@
+import string
+
+
+def simple_calculator(calculation:str):
+    """Receives 'calculation' and returns the calculated result,
+
+       Examples - input -> output:
+       '2 * 3' -> 6
+       '2 + 6' -> 8
+
+       Support +, -, * and /, use "true" division (so 2/3 is .66
+       rather than 0)
+
+       Make sure you convert both numbers to ints.
+       If bad data is passed in, raise a ValueError.
+    """
+    num1, operator, num2 = calculation.split(" ")
+    if not num1.lstrip("-").isdigit() and not num2.lstrip("-").isdigit():
+        raise ValueError
+    if operator == "+":
+        return int(num1)+int(num2)
+    elif operator == "-":
+        return int(num1)-int(num2)
+    elif operator == "*":
+        return int(num1)*int(num2)
+    elif operator == "/" and num2 == "0":
+        # return float(num1)/float(num2)
+        raise ValueError
+    elif operator == "/" and num2 != "0":
+        return round(float(num1)/float(num2),ndigits=2)
+    else:
+        raise ValueError
+

159/test_calculator.py

@@ -0,0 +1,49 @@
+import pytest
+
+from calculator import simple_calculator
+
+
+@pytest.mark.parametrize("arg, expected", [
+    ('2 + 3', 5),
+    ('5 + 11', 16),
+    ('12 + 18', 30),
+])
+def test_sum(arg, expected):
+    assert simple_calculator(arg) == expected
+
+
+@pytest.mark.parametrize("arg, expected", [
+    ('3 - 2', 1),
+    ('16 - 11', 5),
+    ('12 - 18', -6),
+])
+def test_subtract(arg, expected):
+    assert simple_calculator(arg) == expected
+
+
+@pytest.mark.parametrize("arg, expected", [
+    ('2 * 3', 6),
+    ('-5 * -11', 55),
+    ('3 * -6', -18),
+])
+def test_multiply(arg, expected):
+    assert simple_calculator(arg) == expected
+
+
+@pytest.mark.parametrize("arg, expected", [
+    ('2 / 3', 0.67),
+    ('1 / 5', 0.2),
+    ('-2 / 175', -0.01),
+])
+def test_true_division(arg, expected):
+    assert round(simple_calculator(arg), 2) == expected
+
+
+@pytest.mark.parametrize("arg", [
+    'a / 3', '2 / b', 'c / d', '1 2 3', '1 ^ 2',
+    '1 x 2', 'some random string', '1 / 0',
+    'really_bad_data'
+])
+def test_bad_inputs(arg):
+    with pytest.raises(ValueError):
+        simple_calculator(arg)