TcHaxx.Snappy.CLI 0.0.5

🚧 WIP

snappy

Snappy is a Snapshot Testing framework, like Verify, designed for TwinCAT 3.

During the assertion phase, Snappy performs the following steps:

1. It serializes the test result and saves it in a file that corresponds to the test-suite and test name.
2. In subsequent test executions, it re-serializes the result and compares it to the existing file.
3. If the two snapshots do not match, the test fails.
   This discrepancy could indicate either an unexpected change or the need to update the reference snapshot to reflect the new result
4. The validated files can the be added to source control.

Example using TcUnit

FUNCTION_BLOCK FB_TcUnitExample EXTENDS FB_TestSuite
VAR
	hr				: HRESULT;		
	fbTcUnitAdapter : FB_TcUnitAdapter;
	
	stActual		: ST_DemoDataType;
	{attribute 'analysis' := '-33'}
	stResult		: ST_VerificationResult;
END_VAR

TEST('Test some stuff with TcHaxx.Snappy');

// ARRANGE

// ACT
stActual := F_CreateDemoData();

// ASSERT
hr := fbTcUnitAdapter.Verify(anyArg:= stActual);

IF NOT PENDING(hr) THEN
	TEST_FINISHED_NAMED('Test some stuff with TcHaxx.Snappy');
END_IF;

Find more examples in the examples PLC project.

Install

Snappy consists of two parts:

• A dotnet CLI tool, called TcHaxx.Snappy.CLI,

  See How to manage .NET tools

• and the TwinCAT library snappy.

Prerequisites

• rplc library is installed.
• Verify - Supported Tool is installed.

TcHaxx.Snappy.CLI

To install the CLI tool execute following command:

dotnet tool install -g TcHaxx.Snappy.CLI

Update

To update to the latest version from Nuget, run:

dotnet tool update -g  TcHaxx.Snappy.CLI

Uninstall

dotnet tool uninstall -g TcHaxx.Snappy.CLI

snappy.library

Download latest releases, either snappy.library and/or snappy.compiled-library and install.

Usage

Before any tests are being run, TcHaxx.Snappy.CLI hast to be started, prior. Run manually via dotnet tools or TwinCAT deployment.

dotnet tools

TcHaxx.Snappy.Verify verify [OPTIONS]

TwinCAT 3 PLC Deployment

See Category Deployment

To automatically start TcHaxx.Snappy.CLI you may want to add following event to your PLC project properties:

Source control: Received and Verified files

When dealing with source control, consider the following guidelines for handling Received and Verified files:

1. Exclusion:

   • Exclude all files with the pattern *.received.* from source control.
   • To achieve this, add the following line to your .gitignore file:

     *.received.*
     

2. Commitment:

   • On the other hand, commit all files with the pattern *.verified.* to source control.

See Verify/README

Acknowledgments

• TcUnit - A unit testing framework for Beckhoff's TwinCAT 3
• CommandLineParser - A command line parsing library for .NET applications.
• Verify - A library used for snapshot testing.
• Serilog - A logging library for .NET applications.