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Python Code Samples

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3 matches
Cloud + Python medium

Mock CDK Synth Output in Python for Template Testing

Simulate AWS CDK synth output with MagicMock to test or preview CloudFormation templates without running a real CDK app.

aws cdk cloudformation
Python 
import json
from unittest.mock import MagicMock

def mock_cdk_synth() -> dict:
    """Simulate AWS CDK synth output for a simple S3 bucket."""
    cdk_app = MagicMock()
    cdk_app.synth.return_value.template = {
        "Resources": {
            "MyBucket": {
                "Type": "AWS::S3::Bucket",
              …
12 0 Open
Testing & modern typing easy

How to Mock return_value with MagicMock in Python unittest

Use unittest.mock.MagicMock to replace a dependency and set return_value to control what a mocked method returns during unit tests.

unittest mock magicmock
Python 
import unittest
from unittest.mock import MagicMock


class PaymentGateway:
    def charge(self, amount):
        raise NotImplementedError


class OrderService:
    def __init__(self, gateway):
        self.gateway = gateway

    def process_order(self, amount):
        return self.gateway.charge(amount)


class Test…
12 0 Open
Testing & modern typing easy

How to Use mock.assert_called_with in Python

Verify that a MagicMock received a call with specific positional and keyword arguments using assert_called_with in unittest.

unittest mock testing
Python 
import unittest
from unittest.mock import MagicMock

class TestMockAssertions(unittest.TestCase):
    def test_assert_called_with(self):
        # Create a mock object
        mock = MagicMock()

        # Call the mock with specific arguments
        mock.send_email("alice@example.com", subject="Greetings", body="Hel…
14 0 Open

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