SparkyTools.DependencyProvider 1.2.1

Install-Package SparkyTools.DependencyProvider -Version 1.2.1
dotnet add package SparkyTools.DependencyProvider --version 1.2.1
<PackageReference Include="SparkyTools.DependencyProvider" Version="1.2.1" />
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add SparkyTools.DependencyProvider --version 1.2.1
The NuGet Team does not provide support for this client. Please contact its maintainers for support.
#r "nuget: SparkyTools.DependencyProvider, 1.2.1"
#r directive can be used in F# Interactive, C# scripting and .NET Interactive. Copy this into the interactive tool or source code of the script to reference the package.
// Install SparkyTools.DependencyProvider as a Cake Addin
#addin nuget:?package=SparkyTools.DependencyProvider&version=1.2.1

// Install SparkyTools.DependencyProvider as a Cake Tool
#tool nuget:?package=SparkyTools.DependencyProvider&version=1.2.1
The NuGet Team does not provide support for this client. Please contact its maintainers for support.

SparkyTools.DependencyProvider

see also:


Ludicrously lightweight dependency wrapper/provider to improve testability of classes that use dependencies that aren't easily mockable (e.g. System.DateTime):

using SparkyTools.DependencyProvider;
    public class Foo
    {
        private readonly IBar _bar;
        private readonly DependencyProvider<DateTime> _currentTimeProvider;
       
        public Foo(IBar bar, DependencyProvider<DateTime> currentTimeProvider) 
        {
            _bar = bar;
            _getDate = currentTimeProvider;
        }
       
        public void DoSomethingWithBazAndDate()
        {
            _bar.DoSomethingWithDate(_currentTimeProvider.GetValue());
        }
    }

The DependencyProvider.GetValue() function provides a value to the class.

A DependencyProvider instance can be created:

  • via a "callback function" constructor parameter:
    var realTimeProvider = new DependencyProvider<DateTime>(() => DateTime.Now);
    var fakeTimeProvider = new DependencyProvider<DateTime>(() => new DateTime(2018, 7, 4, 15, 32, 00));
    
  • via the static Create(callbackFunction) method:
    var realTimeProvider = DependencyProvider.Create(() => DateTime.Now);
    var fakeTimeProvider = DependencyProvider.Create(() => new DateTime(2018, 7, 4, 15, 32, 00));
    
  • via a static value constructor parameter:
    var realTimeProvider = new DependencyProvider<DateTime>(DateTime.Now);
    var fakeTimeProvider = new DependencyProvider<DateTime>(new DateTime(2018, 7, 4, 15, 32, 00));
    
  • via the static Create(staticValue) method:
    var realTimeProvider = DependencyProvider.Create(DateTime.Now);
    var fakeTimeProvider = DependencyProvider.Create(new DateTime(2018, 7, 4, 15, 32, 00));
    
  • via implicit conversion:
    DependencyProvider<DateTime> realTimeProvider = DateTime.Now(); 
    DependencyProvider<DateTime> fakeTimeProvider = new DateTime(2018, 7, 4, 15, 32, 00);
    

The implicit conversion option makes for very nice, terse syntax when declared inline for the constructor of a class using DependencyProvider, e.g.:

    public class Foo
    {
        public Foo(IBar bar, DependencyProvider<DateTime> currentTimeProvider) { }
    }

    ...
    // implicit conversion:
    var fooWithRealTime = new Foo(bar, DateTime.Now());
    var fooWithFakeTime = new Foo(bar, new DateTime(2018, 7, 4, 15, 32, 00));

    // other syntaxes:
    var fooWithRealTime2 = new Foo(bar, DependencyProvider.Create(DateTime.Now));
    var foowithFakeTime2 = new Foo(bar, new DependencyProvider<DateTime>(new DateTime(2018, 7, 4, 15, 32, 00)));

The DependencyProvider.Static() method tells the provider to cache the first value returned by GetValue() and return that same value for all subsequent calls:

    var startTimeProvider = DependencyProvider.Create(() => DateTime.Now).Static();

DependencyProviders created via the static value constructor and Create(staticValue) methods get their static values when constructed. Providers that aren't constructed statically but are "dotted" with .Static() are "lazy". They don't get retrieve their value until the first GetValue() call.

NuGet packages (3)

Showing the top 3 NuGet packages that depend on SparkyTools.DependencyProvider:

Package Downloads
SparkyTools.XmlConfig

Makes it easy to load a strongly-typed object (or IList of objects) from a custom web.config or app.config file section without having to write a custom IConfigurationSectionHandler implementation.

SparkyTestHelpers.AppSettings

Helpers for testing code that uses ConfigurationManager.AppSettings

SparkyTools.XmlConfig.Fx

Makes it easy to load a strongly-typed object (or IList of objects) from a custom web.config or app.config file section without having to write a custom IConfigurationSectionHandler implementation.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last updated
1.2.1 845 7/27/2019
1.2.0 342 3/23/2019
1.1.0 1,067 3/9/2018
1.0.0 988 2/17/2018

v1.2 Added IDependencyProvider interface