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Testing & modern typing

pytest basics, mocks, type hints, TypedDict, Protocol, and static-checking patterns.

4 matches

How to Parse Data with Type Hints in Python

A beginner-friendly helper that parses simple dictionary- or list-like strings into typed Python structures using modern typing annotations.

type-hints parsing typing

Python

from typing import Any, Dict, List, Union


def parse_data(raw: str) -> Union[Dict[str, Any], List[Any], str]:
    """Parse a simple string into structured data using type hints."""
    cleaned = raw.strip()
    
    if not cleaned:
        return {}
    
    if cleaned.startswith("{") and cleaned.endswith("}"):
     …

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Testing & modern typing easy

How to Use TypedDict and Dataclasses in Python

Create typed data structures with TypedDict and dataclasses, then use them as helper functions for describing objects in a type-safe way.

typing typdict dataclass

Python

from typing import TypedDict, NotRequired, Optional
from dataclasses import dataclass


class User(TypedDict):
    name: str
    age: NotRequired[int]
    email: Optional[str]


@dataclass
class Product:
    id: int
    title: str
    price: float = 0.0


def describe_user(user: User) -> str:
    age = user.get("age",…

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Testing & modern typing easy

How to Use TypedDict for Structured Dict Typing in Python

Define and use TypedDict to add type hints to dictionaries, improving code clarity and enabling static type checking in your Python projects.

typing typeddict type-hints

Python

from typing import TypedDict


class User(TypedDict):
    name: str
    age: int
    email: str


def greet(user: User) -> str:
    return f"Hello {user['name']}, age {user['age']}, contact {user['email']}"


if __name__ == "__main__":
    alice: User = {"name": "Alice", "age": 30, "email": "alice@example.com"}
    pr…

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Testing & modern typing easy

How to Use setUp and tearDown in Python unittest TestCase

Demonstrates how to structure unit tests with setUp and tearDown methods in Python's unittest framework for reusable test fixtures.

unittest testing setupteardown

Python

import unittest


class ExampleTest(unittest.TestCase):
    def setUp(self):
        self.data = [1, 2, 3]

    def tearDown(self):
        self.data = None

    def test_length(self):
        self.assertEqual(len(self.data), 3)

    def test_contains(self):
        self.assertIn(2, self.data)


if __name__ == "__main…

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