feat: Add integration testing framework for PowerShell Lambda runtime

[austoonz]

Issue #, if available:

• The value of $LambdaContext.InvokedFunctionArn is incorrect #45

Description of changes:

Overview

Adds integration testing framework for PowerShell Lambda Runtime.

Key Changes

Integration Testing

• CloudFormation template with Lambda functions for Script, Function, and Module handlers
• Test runner updates (Invoke-Tests.ps1) with integration test support and AWS environment setup
• Helper libraries (LambdaIntegrationHelpers.psm1) for response caching and validation

Bug Fixes

• Environment variable fix from AWS_LAMBDA_RUNTIME_INVOKE_FUNCTION_ARN to AWS_LAMBDA_RUNTIME_INVOKED_FUNCTION_ARN
• C# constructor fix in PowerShellLambdaContext.cs for InvokedFunctionArn assignment

Documentation

• Updated README files with integration testing instructions
• Infrastructure documentation for CloudFormation deployment

Usage

# Run automated tests
cd powershell-runtime && pwsh -NoProfile -Command "& './tests/Invoke-Tests.ps1'"

# Run integration tests (manual, after deploying integration test infrastructure)
cd powershell-runtime && pwsh -NoProfile -Command "& './tests/Invoke-Tests.ps1' -TestType Integration"

Test output

The following is output from a successful invocation of the integration tests.

PS> pwsh -NoProfile -c "./Invoke-Tests.ps1 -TestType Integration -StackName powershell-runtime-integration-test-infrastructure -Region us-west-2 -ProfileName default"
PowerShell Runtime Test Runner
===============================
Loading test requirements from: /workspace/aws-lambda-powershell-runtime/powershell-runtime/test-requirements.psd1
Initializing test framework...
Pester ready
Setting up integration test environment...
Importing required AWS modules...
AWS modules imported successfully
Retrieving stack outputs for powershell-runtime-integration-test-infrastructure...
Setting PWSH_TEST_FUNCTIONHANDLERFUNCTIONARN = arn:aws:lambda:us-west-2:123456789012:function:powershell-runtime-integra-FunctionHandlerFunction-1Xrf87Wpz8hF
Setting PWSH_TEST_FUNCTIONHANDLERFUNCTIONNAME = powershell-runtime-integra-FunctionHandlerFunction-1Xrf87Wpz8hF
Setting PWSH_TEST_INTEGRATIONTESTBUCKETNAME = powershell-runtime-integrati-integrationtestbucket-nkwp213cyf9q
Setting PWSH_TEST_LAMBDAEXECUTIONROLEARN = arn:aws:iam::123456789012:role/powershell-runtime-integration--LambdaExecutionRole-EEBG0sMMDo4p
Setting PWSH_TEST_MODULEHANDLERFUNCTIONARN = arn:aws:lambda:us-west-2:123456789012:function:powershell-runtime-integrati-ModuleHandlerFunction-QSYyID5uFT87
Setting PWSH_TEST_MODULEHANDLERFUNCTIONNAME = powershell-runtime-integrati-ModuleHandlerFunction-QSYyID5uFT87
Setting PWSH_TEST_POWERSHELLRUNTIMELAYERARN = arn:aws:lambda:us-west-2:123456789012:layer:PwshRuntimeLayer:64
Setting PWSH_TEST_SCRIPTHANDLERFAILINGFUNCTIONARN = arn:aws:lambda:us-west-2:123456789012:function:powershell-runtime-integr-ScriptHandlerFailingFunc-2YXISzOx5cBJ
Setting PWSH_TEST_SCRIPTHANDLERFAILINGFUNCTIONNAME = powershell-runtime-integr-ScriptHandlerFailingFunc-2YXISzOx5cBJ
Setting PWSH_TEST_SCRIPTHANDLERFUNCTIONARN = arn:aws:lambda:us-west-2:123456789012:function:powershell-runtime-integrati-ScriptHandlerFunction-QBvNUkOKzt8c
Setting PWSH_TEST_SCRIPTHANDLERFUNCTIONNAME = powershell-runtime-integrati-ScriptHandlerFunction-QBvNUkOKzt8c
Setting configuration environment variables...
Setting PWSH_TEST_STACK_NAME = powershell-runtime-integration-test-infrastructure
Setting PWSH_TEST_AWS_REGION = us-west-2
Setting PWSH_TEST_PROFILE_NAME = default
Successfully set 11 stack output environment variables for integration tests
Environment variable PWSH_TEST_INFRASTRUCTURE_DEPLOYED has been set to TRUE
Configuration environment variables (PWSH_TEST_STACK_NAME, PWSH_TEST_AWS_REGION, PWSH_TEST_PROFILE_NAME) have been set
Test paths: /workspace/aws-lambda-powershell-runtime/powershell-runtime/tests/integration

Executing tests...

Starting discovery in 2 files.
Discovery found 11 tests in 88ms.
Running tests.
Initializing error response cache...
Error response cached successfully.
[+] /workspace/aws-lambda-powershell-runtime/powershell-runtime/tests/integration/ErrorHandling.Tests.ps1 9.48s (9.3s|109ms)
Initializing handler response cache...
Response cache initialized successfully.
[+] /workspace/aws-lambda-powershell-runtime/powershell-runtime/tests/integration/Lambda-Integration.Tests.ps1 17.15s (17.1s|34ms)
Tests completed in 26.64s
Tests Passed: 11, Failed: 0, Skipped: 0, Inconclusive: 0, NotRun: 0

Test Results:
Tests: 11/11 passed
Cleaning up integration test environment variables...
Removing PWSH_TEST_INTEGRATIONTESTBUCKETNAME
Removing PWSH_TEST_STACK_NAME
Removing PWSH_TEST_SCRIPTHANDLERFUNCTIONARN
Removing PWSH_TEST_FUNCTIONHANDLERFUNCTIONNAME
Removing PWSH_TEST_MODULEHANDLERFUNCTIONNAME
Removing PWSH_TEST_LAMBDAEXECUTIONROLEARN
Removing PWSH_TEST_MODULEHANDLERFUNCTIONARN
Removing PWSH_TEST_INFRASTRUCTURE_DEPLOYED
Removing PWSH_TEST_SCRIPTHANDLERFAILINGFUNCTIONNAME
Removing PWSH_TEST_FUNCTIONHANDLERFUNCTIONARN
Removing PWSH_TEST_AWS_REGION
Removing PWSH_TEST_POWERSHELLRUNTIMELAYERARN
Removing PWSH_TEST_SCRIPTHANDLERFUNCTIONNAME
Removing PWSH_TEST_PROFILE_NAME
Removing PWSH_TEST_SCRIPTHANDLERFAILINGFUNCTIONARN
Successfully cleaned up 15 integration test environment variables

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