You&#39;re supposed to `await` the result (see [xunit&#39;s acceptance tests](https://github.com/xunit/xunit/blob/master/test/test.xunit.assert/Asserts/ExceptionAssertsTests.cs#L140)).

    [Fact] public async Task Test1()
    {
        await Assert.ThrowsAsync&lt;ArgumentNullException&gt;(() =&gt; MethodThatThrows());
    }

In this specific degenerate case, you could just `return` the `Task` that `Assert.ThrowsAsync` yields without using `await`, but the key thing is you need to hand the resulting `Task` back to the xUnit framework, i.e.

    [Fact]
    public Task Test1() =&gt;
        Assert.ThrowsAsync&lt;ArgumentNullException&gt;(MethodThatThrows);

Just in case anyone wants to separate Act and Assert part, below code can be used:

    //Act
    Task result() =&gt; systemUnderTest.AsyncMethodThatThrows();
    
    //Assert
    await Assert.ThrowsAsync&lt;Exception&gt;(result); 

      

I have a `Text` with long text inside a `ScrollView` and I want to detect when the user has scrolled to the end of the text so I can enable a button.

I&#39;ve been debugging the event object from the `onScroll` event but there doesn&#39;t seem any value I can use.

Detect ScrollView has reached the end

Is there any possible way to change size of `mat-spinner` or `mat-progress-circle`?

I read the documentation of `mat-spinner` and `mat-progress-circle` but they said that `mat-diameter` is discontinued and the spinner will take the parent element&#39;s size. 

How can I put `mat-spinner` in a `mat-button` to the left corner without changing the height of the button?

    &lt;button mat-button&gt;
       &lt;mat-spinner style=&quot;float:left;&quot;&gt;&lt;/mat-spinner&gt; 
       processing....
    &lt;/button&gt;

I also tried to change the height using in-line css like 

    style=&quot;float:left;height:10px;width:10px;
but is not pretty to see.

angular/material2 mat-spinner resize

So I have a test like the following:

    	[Fact]
		public void Test1()
		{
			Assert.ThrowsAsync&lt;ArgumentNullException&gt;(() =&gt; MethodThatThrows());
		}

		private async Task MethodThatThrows()
		{
			await Task.Delay(100);
			throw new NotImplementedException();
		}

To my surprise, Test1 passes successfully. To make it fail I have to write like this:

    Assert.Throws&lt;ArgumentNullException&gt;(() =&gt; MethodThatThrows().Wait());

What is the purpose of ThrowsAsync(), if it does not work in the scenario above?

xunit Assert.ThrowsAsync() does not work properly?

So I have a test like the following:
<pre><code class="hljs language-csharp">	[Fact]
	public void Test1()
	{
		Assert.ThrowsAsync&#x3C;ArgumentNullException>(() => MethodThatThrows());
	}

	private async Task MethodThatThrows()
	{
		await Task.Delay(100);
		throw new NotImplementedException();
	}
</code></pre>
To my surprise, Test1 passes successfully. To make it fail I have to write like this:
<pre><code class="hljs language-scss">Assert.Throws&#x3C;ArgumentNullException>(() => MethodThatThrows().Wait());
</code></pre>
What is the purpose of ThrowsAsync(), if it does not work in the scenario above?

I was testing what was returned from division including zeroes i.e. `0/1`, `1/0` and `0/0`. For this I used something similar to the following:

    Console.WriteLine(1d / 0d);

However this code prints `8` not `Infinity` or some other string constant like `PositiveInfinity`.

For completeness all of the following print `8`:

    Console.WriteLine(1d / 0d);

    double value = 1d / 0d;
    Console.WriteLine(value);

    Console.WriteLine(Double.PositiveInfinity);

And `Console.WriteLine(Double.NegativeInfinity);` prints `-8`.

Why does this infinity print 8?

----------

For those of you who seem to think this is an infinity symbol not an eight the following program:

    Console.WriteLine(1d / 0d);

    double value = 1d / 0d;
    Console.WriteLine(value);

    Console.WriteLine(Double.PositiveInfinity);

    Console.WriteLine(8);

Outputs:

[![Inifinity output][1]][1]

  [1]: https://i.stack.imgur.com/ODbah.png

Why is infinity printed as &quot;8&quot; in the Windows 10 console?

I am trying to check the **balance** of a given Bitcoin address by using ***ONLY*** the locally stored blockchain (downloaded via Bitcoin Core). Something similar to this (by using NBitCoin and/or QBitNinja), but without needing access to the network:

    private static readonly QBitNinjaClient client = new QBitNinjaClient(Network.Main);

    public decimal CheckBalance(BitcoinPubKeyAddress address)
    {
        var balanceModel = client.GetBalance(address, true).Result;
        decimal balance = 0;

        if (balanceModel.Operations.Count &gt; 0)
        {
            var unspentCoins = new List&lt;Coin&gt;();
            foreach (var operation in balanceModel.Operations)
                unspentCoins.AddRange(operation.ReceivedCoins.Select(coin =&gt; coin as Coin));
            balance = unspentCoins.Sum(x =&gt; x.Amount.ToDecimal(MoneyUnit.BTC));
        }
        return balance;
    }

The example above needs access to the network. I need to do the same thing offline. I came up with something like this, but obviously it doesn&#39;t work:

    public decimal CheckBalanceLocal(BitcoinPubKeyAddress address)
    {
        var node = Node.ConnectToLocal(Network.Main);
        node.VersionHandshake();
        var chain = node.GetChain();

        var store = new BlockStore(@&quot;F:\Program Files\Bitcoin\Cache\blocks&quot;, Network.Main);
            
        var index = new IndexedBlockStore(new InMemoryNoSqlRepository(), store);
        index.ReIndex();

        var headers = chain.ToEnumerable(false).ToArray();

        var balance = (
            from header in headers
            select index.Get(header.HashBlock) 
            into block
            from tx in block.Transactions
            from txout in tx.Outputs
            where txout.ScriptPubKey.GetDestinationAddress(Network.Main) == address
            select txout.Value.ToDecimal(MoneyUnit.BTC)).Sum();
                
        return balance;
    }

 1. It hangs during the query
 2. I want something instead of `InMemoryNoSqlRepository` to be stored in a file in order to prevent using `ReIndex()` which slows everything down

My requirement is to ***Check Balance*** the same way as in the first method but by querying blocks stored on my disk.

Actually what I require might just be an answer to [this question][1]: 


  [1]: https://bitcoin.stackexchange.com/questions/50817/how-to-run-qbitninja-server-locally

Query LOCAL Bitcoin blockchain with C# .NET

I decompiled some C# 7 libraries and saw `ValueTuple` generics being used. What are `ValueTuples` and why not `Tuple` instead?

* https://docs.microsoft.com/en-gb/dotnet/api/system.tuple
* https://docs.microsoft.com/en-gb/dotnet/api/system.valuetuple

What&#39;s the difference between System.ValueTuple and System.Tuple?

While trying to connect to Nuget, I&#39;m getting the error below, and then I am unable to connect: 

&gt;   [nuget.org] Unable to load the service index for source
&gt; https://api.nuget.org/v3/index.json.
&gt;       An error occurred while sending the request.
&gt;       Unable to connect to the remote server
&gt;       A connection attempt failed because the connected party did not properly respond after a period of time, or established connection
&gt; failed because connected host has failed to respond 68.232.34.200:443

I am able to access `https://api.nuget.org/v3/index.json` on my browser.

This question is not a duplicate. The other answers don&#39;t solve my problem.

Nuget connection attempt failed &quot;Unable to load the service index for source&quot;

I&#39;ve read some information about generics in .ΝΕΤ and noticed one interesting thing.

For example, if I have a generic class:

    class Foo&lt;T&gt; 
    { 
        public static int Counter; 
    }
    
    Console.WriteLine(++Foo&lt;int&gt;.Counter); //1
    Console.WriteLine(++Foo&lt;string&gt;.Counter); //1

Two classes `Foo&lt;int&gt;` and `Foo&lt;string&gt;` are different at runtime. But what about case when non-generic class having generic method?

    class Foo 
    {
        public void Bar&lt;T&gt;()
        {
        }
    }

It&#39;s obvious that there&#39;s only one `Foo` class. But what about method `Bar`? All the generic classes and methods are closed at runtime with parameters they used with. Does it mean that class `Foo` has many implementations of `Bar` and where the information about this method stored in memory?

Where are generic methods stored?

I feel like I&#39;m missing something really obvious here. I have classes that require injecting of options using the .NET Core `IOptions` pattern(?). When I unit test that class, I want to mock various versions of the options to validate the functionality of the class. Does anyone know how to correctly mock/instantiate/populate `IOptions&lt;T&gt;` outside of the Startup class? 


Here are some samples of the classes I&#39;m working with:

Settings/Options Model   
 
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Threading.Tasks;
    
    namespace OptionsSample.Models
    {
        public class SampleOptions
        {
            public string FirstSetting { get; set; }
            public int SecondSetting { get; set; }
        }
    }

 
Class to be tested which uses the Settings:


    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Threading.Tasks;
    using OptionsSample.Models
    using System.Net.Http;
    using Microsoft.Extensions.Options;
    using System.IO;
    using Microsoft.AspNetCore.Http;
    using System.Xml.Linq;
    using Newtonsoft.Json;
    using System.Dynamic;
    using Microsoft.Extensions.Logging;
    
    namespace OptionsSample.Repositories
    {
        public class SampleRepo : ISampleRepo
        {
            private SampleOptions _options;
            private ILogger&lt;AzureStorageQueuePassthru&gt; _logger;
    
            public SampleRepo(IOptions&lt;SampleOptions&gt; options)
            {
                _options = options.Value;
            }
    
            public async Task Get()
            {
            }
        }
    }

Unit test in a different assembly from the other classes:

    using OptionsSample.Repositories;
    using OptionsSample.Models;
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Threading.Tasks;
    using Xunit;
    using Microsoft.Extensions.Logging;
    using Microsoft.AspNetCore.Http;
    using Microsoft.Extensions.Options;
    using Microsoft.Extensions.DependencyInjection;
    using Microsoft.Extensions.Configuration;
    
    namespace OptionsSample.Repositories.Tests
    {
        public class SampleRepoTests
        {
            private IOptions&lt;SampleOptions&gt; _options;
            private SampleRepo _sampleRepo;
    
    
            public SampleRepoTests()
            {
    			//Not sure how to populate IOptions&lt;SampleOptions&gt; here
                _options = options;
    
    			_sampleRepo = new SampleRepo(_options);
            }
        }
    }



.NET Core Unit Testing - Mock IOptions&lt;T&gt;

How can I use injection with Mockito and JUnit 5?

In JUnit4 I can just use the `@RunWith(MockitoJUnitRunner.class) ` Annotation. In JUnit5 is no `@RunWith` Annotation?

How to use Mockito with JUnit5

We have done one angular2 project set up and inside that created one module (my-module) and inside that module created one component (my-new-component) using following cmd commands: 

    ng new angular2test
    cd angular2test
    ng g module my-module
    ng generate component my-new-component

*After creating the set up and all components, we ran `ng test` command from cmd inside angular2test folder.*

**The below file is our  my-new-component.component.ts file**:

&lt;!-- language: typescript --&gt;

    import { Component, OnInit } from &#39;@angular/core&#39;;
    import { Router, Routes, RouterModule } from &#39;@angular/router&#39;;
    import { DummyService } from &#39;../services/dummy.service&#39;;
    
    @Component({
      selector: &#39;app-my-new-component&#39;,
      templateUrl: &#39;./my-new-component.component.html&#39;,
      styleUrls: [&#39;./my-new-component.component.css&#39;]
    })
    export class MyNewComponentComponent implements OnInit {
    
      constructor(private router : Router, private dummyService:DummyService) { }
    
      ngOnInit() {
      }
        redirect() : void{
            //this.router.navigate([&#39;/my-module/my-new-component-1&#39;])
        }
    }

**The below file is our  my-new-component.component.spec.ts file**:

&lt;!-- language: typescript --&gt;

    /* tslint:disable:no-unused-variable */
    import { async, ComponentFixture, TestBed } from &#39;@angular/core/testing&#39;;
    import { By } from &#39;@angular/platform-browser&#39;;
    import { DebugElement } from &#39;@angular/core&#39;;
    
    import { RouterTestingModule } from &#39;@angular/router/testing&#39;;
    import {NgbModule} from &#39;@ng-bootstrap/ng-bootstrap&#39;;
    import { DummyService } from &#39;../services/dummy.service&#39;;
    
    import { MyNewComponentComponent } from &#39;./my-new-component.component&#39;;
    
    describe(&#39;MyNewComponentComponent&#39;, () =&gt; {
      let component: MyNewComponentComponent;
      let fixture: ComponentFixture&lt;MyNewComponentComponent&gt;;
    
      beforeEach(async(() =&gt; {
        TestBed.configureTestingModule({
    		imports: [RouterTestingModule, NgbModule.forRoot(), DummyService],
          declarations: [ MyNewComponentComponent ]
        })
        .compileComponents();
      }));
    
      beforeEach(() =&gt; {
        fixture = TestBed.createComponent(MyNewComponentComponent);
        component = fixture.componentInstance;
        fixture.detectChanges();
      });
    
      it(&#39;should create&#39;, () =&gt; {
        expect(component).toBeTruthy();
      }); 
    });

We are getting the below cmd error while running the ng test command:

        Chrome 54.0.2840 (Windows 7 0.0.0): Executed 1 of 1 (1 FAILED) ERROR (0.593 secs / 2.007 secs)
    Chrome 54.0.2840 (Windows 7 0.0.0) MyNewComponentComponent should create FAILED
            Failed: Unexpected value &#39;DummyService&#39; imported by the module &#39;DynamicTestModule&#39;
            Error: Unexpected value &#39;DummyService&#39; imported by the module &#39;DynamicTestModule&#39;

We have updated the component file and the spec file. Pleased find below the code snippet.

**The below file is our  my-new-component.component.ts file**:

&lt;!-- language: typescript --&gt;

    import { Component, OnInit } from &#39;@angular/core&#39;;
    import { Router, Routes, RouterModule } from &#39;@angular/router&#39;;
    import { DummyService } from &#39;../services/dummy.service&#39;;
    
    @Component({
      selector: &#39;app-my-new-component&#39;,
      templateUrl: &#39;./my-new-component.component.html&#39;,
      styleUrls: [&#39;./my-new-component.component.css&#39;]
    })
    export class MyNewComponentComponent implements OnInit {
    
      constructor(private router : Router, private dummyService:DummyService, public fb: FormBuilder) { 
      super(fb);
      }
    
      ngOnInit() {
      }
        redirect() : void{
            //this.router.navigate([&#39;/my-module/my-new-component-1&#39;])
        }
    }

**The below file is our  my-new-component.component.spec.ts file**:

&lt;!-- language: typescript --&gt;

    /* tslint:disable:no-unused-variable */
    import { async, ComponentFixture, TestBed } from &#39;@angular/core/testing&#39;;
    import { By } from &#39;@angular/platform-browser&#39;;
    import { DebugElement } from &#39;@angular/core&#39;;
    import { FormsModule, FormGroup, FormBuilder, Validators, ReactiveFormsModule} from &#39;@angular/forms&#39;;
    import { SplitPipe } from &#39;../../common/pipes/string-split.pipe&#39;;
    import { RouterTestingModule } from &#39;@angular/router/testing&#39;;
    import { DummyService } from &#39;../services/dummy.service&#39;;
    import { MyNewComponentComponent } from &#39;./my-new-component.component&#39;;
    
    describe(&#39;MyNewComponentComponent&#39;, () =&gt; {
      let component: MyNewComponentComponent;
      let fixture: ComponentFixture&lt;MyNewComponentComponent&gt;;
    
      beforeEach(async(() =&gt; {
        TestBed.configureTestingModule({
            imports: [RouterTestingModule, DummyService ,HttpModule, FormBuilder],
          declarations: [ MyNewComponentComponent, SplitPipe]
        })
        .compileComponents();
      }));
    
      beforeEach(() =&gt; {
        fixture = TestBed.createComponent(MyNewComponentComponent);
        component = fixture.componentInstance;
        fixture.detectChanges();
      });
    
      it(&#39;should create&#39;, () =&gt; {
        expect(component).toBeTruthy();
      }); 
    });

But while running the ng test command, we are getting the below error.

    09 12 2016 09:13:48.987:WARN [karma]: No captured browser, open http://localhost:9876/
    09 12 2016 09:13:49.008:INFO [karma]: Karma v1.2.0 server started at http://localhost:9876/
    09 12 2016 09:13:49.010:INFO [launcher]: Launching browser Chrome with unlimited concurrency
    09 12 2016 09:13:49.420:INFO [launcher]: Starting browser Chrome
    09 12 2016 09:13:58.642:INFO [Chrome 54.0.2840 (Windows 7 0.0.0)]: Connected on socket /#QZ9LSSUVeK6KwNDlAAAA with id 46830907
            Failed: Unexpected value &#39;FormBuilder&#39; imported by the module &#39;DynamicTestModule&#39;
            Error: Unexpected value &#39;FormBuilder&#39; imported by the module &#39;DynamicTestModule&#39;








&quot;Error: No provider for router&quot; while writing Karma-Jasmine unit test cases

I am attempting to mock a public class, however when doing so, Mockito throws an `Mockito cannot mock this class` exception.

Class I wish to mock: https://github.com/scribejava/scribejava/blob/master/scribejava-core/src/main/java/com/github/scribejava/core/builder/ServiceBuilder.java

Test code:

    package xyz.jacobclark.adapter;
    
    import com.github.scribejava.apis.TwitterApi;
    import com.github.scribejava.core.builder.ServiceBuilder;
    import com.github.scribejava.core.model.OAuth1RequestToken;
    import com.github.scribejava.core.oauth.OAuth10aService;
    import org.junit.Assert;
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.mockito.Mock;
    import org.mockito.junit.MockitoJUnitRunner;
    
    import java.io.IOException;
    
    import static org.hamcrest.Matchers.is;
    import static org.hamcrest.core.IsInstanceOf.any;
    
    @RunWith(MockitoJUnitRunner.class)
    public class TwitterOAuthAdapterTest {
        @Mock
        ServiceBuilder serviceBuilder;
    
        @Test
        public void getRequestTokenShouldReturnAValidRequestToken() throws IOException {
            class TwitterOAuthAdapter {
                private final OAuth10aService service;
    
                public TwitterOAuthAdapter(ServiceBuilder serviceBuilder){
                    this.service = serviceBuilder
                        .apiKey(&quot;&quot;)
                        .apiSecret(&quot;&quot;)
                        .build(TwitterApi.instance());
                }
    
                public OAuth1RequestToken getRequestToken() throws IOException {
                    return this.service.getRequestToken();
                }
            }
    
            TwitterOAuthAdapter oAuthAdapter = new TwitterOAuthAdapter(serviceBuilder);
            Assert.assertThat(oAuthAdapter.getRequestToken(), is(any(OAuth1RequestToken.class)));
        }
    }


Full stacktrace:

    xyz.jacobclark.adapter.TwitterOAuthAdapterTest
    
    org.mockito.exceptions.base.MockitoException: 
    Mockito cannot mock this class: class com.github.scribejava.core.builder.ServiceBuilder.
    
    Mockito can only mock non-private &amp; non-final classes.
    If you&#39;re not sure why you&#39;re getting this error, please report to the mailing list.
    
    
    Java               : 1.8
    JVM vendor name    : Oracle Corporation
    JVM vendor version : 25.0-b70
    JVM name           : Java HotSpot(TM) 64-Bit Server VM
    JVM version        : 1.8.0-b132
    JVM info           : mixed mode
    OS name            : Mac OS X
    OS version         : 10.11.3
    
    
    Underlying exception : java.lang.IllegalArgumentException: object is not an instance of declaring class
    
    	at org.mockito.internal.runners.SilentJUnitRunner$1.withBefores(SilentJUnitRunner.java:29)
    	at org.junit.runners.BlockJUnit4ClassRunner.methodBlock(BlockJUnit4ClassRunner.java:276)
    	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    	at org.mockito.internal.runners.SilentJUnitRunner.run(SilentJUnitRunner.java:39)
    	at org.mockito.internal.runners.StrictRunner.run(StrictRunner.java:39)
    	at org.mockito.junit.MockitoJUnitRunner.run(MockitoJUnitRunner.java:103)
    	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:117)
    	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:42)
    	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:262)
    	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:84)
    	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    	at java.lang.reflect.Method.invoke(Method.java:483)
    	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
    Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
    	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    	at java.lang.reflect.Method.invoke(Method.java:483)
    	at net.bytebuddy.description.type.TypeDescription$Generic$AnnotationReader$ForTypeArgument.resolve(TypeDescription.java:3843)
    	at net.bytebuddy.description.type.TypeDescription$Generic$AnnotationReader$Delegator$Chained.resolve(TypeDescription.java:3468)
    	at net.bytebuddy.description.type.TypeDescription$Generic$AnnotationReader$ForTypeArgument.resolve(TypeDescription.java:3803)
    	at net.bytebuddy.description.type.TypeDescription$Generic$AnnotationReader$Delegator.asList(TypeDescription.java:3439)
    	at net.bytebuddy.description.type.TypeDescription$Generic$OfWildcardType$ForLoadedType.getDeclaredAnnotations(TypeDescription.java:4748)
    	at net.bytebuddy.description.type.TypeDescription$Generic$Visitor$TypeVariableErasing.onWildcard(TypeDescription.java:680)
    	at net.bytebuddy.description.type.TypeDescription$Generic$Visitor$TypeVariableErasing.onWildcard(TypeDescription.java:663)
    	at net.bytebuddy.description.type.TypeDescription$Generic$OfWildcardType.accept(TypeDescription.java:4656)
    	at net.bytebuddy.description.type.TypeDescription$Generic$Visitor$TypeVariableErasing.onParameterizedType(TypeDescription.java:691)
    	at net.bytebuddy.description.type.TypeDescription$Generic$Visitor$TypeVariableErasing.onParameterizedType(TypeDescription.java:663)
    	at net.bytebuddy.description.type.TypeDescription$Generic$OfParameterizedType.accept(TypeDescription.java:4998)
    	at net.bytebuddy.description.type.TypeList$Generic$AbstractBase.accept(TypeList.java:249)
    	at net.bytebuddy.description.type.TypeDescription$Generic$Visitor$TypeVariableErasing$RetainedTypeVariable.getUpperBounds(TypeDescription.java:832)
    	at net.bytebuddy.description.type.TypeDescription$Generic$OfTypeVariable.asErasure(TypeDescription.java:5373)
    	at net.bytebuddy.description.method.MethodDescription$AbstractBase.asTypeToken(MethodDescription.java:701)
    	at net.bytebuddy.dynamic.scaffold.MethodGraph$Compiler$Default$Key$Harmonized.of(MethodGraph.java:881)
    	at net.bytebuddy.dynamic.scaffold.MethodGraph$Compiler$Default$Key$Store.registerTopLevel(MethodGraph.java:1074)
    	at net.bytebuddy.dynamic.scaffold.MethodGraph$Compiler$Default.doAnalyze(MethodGraph.java:588)
    	at net.bytebuddy.dynamic.scaffold.MethodGraph$Compiler$Default.analyze(MethodGraph.java:548)
    	at net.bytebuddy.dynamic.scaffold.MethodGraph$Compiler$Default.analyzeNullable(MethodGraph.java:567)
    	at net.bytebuddy.dynamic.scaffold.MethodGraph$Compiler$Default.doAnalyze(MethodGraph.java:581)
    	at net.bytebuddy.dynamic.scaffold.MethodGraph$Compiler$Default.compile(MethodGraph.java:521)
    	at net.bytebuddy.dynamic.scaffold.MethodGraph$Compiler$AbstractBase.compile(MethodGraph.java:442)
    	at net.bytebuddy.dynamic.scaffold.MethodRegistry$Default.prepare(MethodRegistry.java:480)
    	at net.bytebuddy.dynamic.scaffold.subclass.SubclassDynamicTypeBuilder.make(SubclassDynamicTypeBuilder.java:160)
    	at net.bytebuddy.dynamic.scaffold.subclass.SubclassDynamicTypeBuilder.make(SubclassDynamicTypeBuilder.java:153)
    	at net.bytebuddy.dynamic.DynamicType$Builder$AbstractBase.make(DynamicType.java:2568)
    	at net.bytebuddy.dynamic.DynamicType$Builder$AbstractBase$Delegator.make(DynamicType.java:2670)
    	at org.mockito.internal.creation.bytebuddy.SubclassBytecodeGenerator.mockClass(SubclassBytecodeGenerator.java:84)
    	at org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator$CachedBytecodeGenerator.getOrGenerateMockClass(TypeCachingBytecodeGenerator.java:91)
    	at org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.mockClass(TypeCachingBytecodeGenerator.java:38)
    	at org.mockito.internal.creation.bytebuddy.SubclassByteBuddyMockMaker.createMockType(SubclassByteBuddyMockMaker.java:67)
    	at org.mockito.internal.creation.bytebuddy.SubclassByteBuddyMockMaker.createMock(SubclassByteBuddyMockMaker.java:38)
    	at org.mockito.internal.creation.bytebuddy.ByteBuddyMockMaker.createMock(ByteBuddyMockMaker.java:26)
    	at org.mockito.internal.util.MockUtil.createMock(MockUtil.java:35)
    	at org.mockito.internal.MockitoCore.mock(MockitoCore.java:63)
    	at org.mockito.Mockito.mock(Mockito.java:1637)
    	at org.mockito.internal.configuration.MockAnnotationProcessor.process(MockAnnotationProcessor.java:33)
    	at org.mockito.internal.configuration.MockAnnotationProcessor.process(MockAnnotationProcessor.java:16)
    	at org.mockito.internal.configuration.DefaultAnnotationEngine.createMockFor(DefaultAnnotationEngine.java:39)
    	at org.mockito.internal.configuration.DefaultAnnotationEngine.process(DefaultAnnotationEngine.java:63)
    	at org.mockito.internal.configuration.InjectingAnnotationEngine.processIndependentAnnotations(InjectingAnnotationEngine.java:59)
    	at org.mockito.internal.configuration.InjectingAnnotationEngine.process(InjectingAnnotationEngine.java:43)
    	at org.mockito.MockitoAnnotations.initMocks(MockitoAnnotations.java:67)
    	... 23 more
    
    
    Test ignored.
    Process finished with exit code 255



Mockito cannot mock this class

I have been reading official Angular2 documentation for unit testing ([https://angular.io/docs/ts/latest/guide/testing.html][1]) but I am struggling with setting a component&#39;s input field value so that its reflected in the component property (bound via ngModel). The screen works fine in the browser, but in the unit test I cannot seem to be able to set the fields value.

I am using below code. &quot;fixture&quot; is properly initialized as other tests are working fine. &quot;comp&quot; is instance of my component, and the input field is bound to &quot;user.username&quot; via ngModel.

    it(&#39;should update model...&#39;, async(() =&gt; {
        let field: HTMLInputElement = fixture.debugElement.query(By.css(&#39;#user&#39;)).nativeElement;
        field.value = &#39;someValue&#39;
        field.dispatchEvent(new Event(&#39;input&#39;));
        fixture.detectChanges();
    
        expect(field.textContent).toBe(&#39;someValue&#39;);
        expect(comp.user.username).toBe(&#39;someValue&#39;);
      }));

My version of Angular2:  `&quot;@angular/core&quot;: &quot;2.0.0&quot;`


  [1]: https://angular.io/docs/ts/latest/guide/testing.html

Angular unit test input value

This is an example from Google Adsense application page. The loading screen displayed before the main page showed after.

[![enter image description here][1]][1]

I don&#39;t know how to do the same thing with React because if I make loading screen rendered by React component, it doesn&#39;t display while page is loading because it has to wait for DOM rendered before.

**Updated**:

I made an example of my approach by putting screen loader in `index.html` and remove it in React `componentDidMount()` lifecycle method.

[Example][2] and [react-loading-screen][3].


  [1]: https://i.stack.imgur.com/ngk1r.gif
  [2]: https://nguyenbathanh.github.io
  [3]: https://github.com/nguyenbathanh/react-loading-screen

React - Display loading screen while DOM is rendering?

I&#39;m using `async`/`await` to fire several `api` calls in parallel:

    async function foo(arr) {
      const results = await Promise.all(arr.map(v =&gt; {
         return doAsyncThing(v)
      }))
      return results
    }

I know that, unlike `loops`, `Promise.all` [executes in-parallel][1] (that is, the waiting-for-results portion is in parallel). 

But [I also know that][2]:

&gt; Promise.all is rejected if one of the elements is rejected and
&gt; Promise.all fails fast: If you have four promises which resolve after
&gt; a timeout, and one rejects immediately, then Promise.all rejects
&gt; immediately.


As I read this, if I `Promise.all` with 5 promises, and the first one to finish returns a `reject()`, then the other 4 are effectively cancelled and their promised `resolve()` values are lost.

Is there a third way? Where execution is effectively in-parallel, but a single failure doesn&#39;t spoil the whole bunch? 



 
 


  [1]: https://stackoverflow.com/questions/35612428/call-async-await-functions-in-parallel
  [2]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/all

How do I await multiple promises in-parallel without &#39;fail-fast&#39; behavior?

Simple question about `try`/`catch` for function in `setTimeout`

    try {
        setTimeout(function () {
            throw new Error(&#39;error!&#39;);
        }, 300)
    } catch (e) {
        console.log(&#39;eeee!&#39;)
        console.log(e)
    }
Why doesn&#39;t catch block work?

What can I read about this?

P.S: the question is about possibility of handling errors like this. Don&#39;t answer about promises.

How to handle errors from setTimeout in JavaScript?

I am experimenting with the `await` keyword in Node.js. I have this test script:

    &quot;use strict&quot;;
    function x() {
      return new Promise(function(resolve, reject) {
        setTimeout(function() {
          resolve({a:42});
        },100);
      });
    }
    await x();

But when I run it in node I get

    await x();
          ^
    SyntaxError: Unexpected identifier

whether I run it with `node` or `node --harmony-async-await` or in the Node.js &#39;repl&#39; on my Mac with Node.js 7.5 or Node.js 8 (nightly build).

Oddly, the same code works in the Runkit JavaScript notebook environment: https://runkit.com/glynnbird/58a2eb23aad2bb0014ea614b

What am I doing wrong?


&#39;await Unexpected identifier&#39; on Node.js 7.5

[`asyncio.gather`][1] and [`asyncio.wait`][2] seem to have similar uses: I have a bunch of async things that I want to execute/wait for (not necessarily waiting for one to finish before the next one starts). They use a different syntax, and differ in some details, but it seems very un-pythonic to me to have 2 functions that have such a huge overlap in functionality. What am I missing?


  [1]: https://docs.python.org/3/library/asyncio-task.html#asyncio.gather
  [2]: https://docs.python.org/3/library/asyncio-task.html#asyncio.wait

Asyncio.gather vs asyncio.wait

The latest version of VS Code already provides an easy way of running a single test as pointed on [Tyler Long&#39;s answer](https://stackoverflow.com/a/38372628/1140754) to the question [Debugging xunit tests in .NET Core and Visual Studio Code](https://stackoverflow.com/q/38146011/1140754).

However, I am looking how can I run **all tests** contained in a test suite class in VS Code (without debug)? 

The only way I found was adding to `launch.json` a specific configuration as the following one, but which I can only run in debug (I would like to run it without debug):

&lt;!-- language: lang-json --&gt;

    {
      &quot;name&quot;: &quot;.NET Core Xunit tests&quot;,
      &quot;type&quot;: &quot;coreclr&quot;,
      &quot;request&quot;: &quot;launch&quot;,
      &quot;preLaunchTask&quot;: &quot;build&quot;,
      &quot;program&quot;: &quot;/usr/local/share/dotnet/dotnet&quot;,
      &quot;args&quot;: [&quot;test&quot;],
      &quot;cwd&quot;: &quot;${workspaceRoot}/test/MyProject.Tests&quot;,
      &quot;externalConsole&quot;: false,
      &quot;stopAtEntry&quot;: false,
      &quot;internalConsoleOptions&quot;: &quot;openOnSessionStart&quot;
    }



How to run all tests in Visual Studio Code

If I set environment variables for a .Net Core web project in Visual Studio 2017 using the project properties page, I can read the value of the variable using `Environment.GetEnvironmentVariable`; however, when I set the environment variable for my xUnit testing project and then debug the test, `Environment.GetEnvironmentVariable` always returns null.  Is there something about the fact that it is a testing project that should prevent the variable from being used the same as with the web project?  If so, is there a way that I can set the environment variables for a test project?  Thank you.

Should GetEnvironmentVariable Work in xUnit Test?

I have in my test suite a test that goes something like this:

    [Fact]
    public void VerifySomeStuff()
    {
        var stuffCollection = GetSomeStuff();

        Assert.Equal(1, stuffCollection.Count());
    }

This test works as I expect, but when I run it xUnit prints a warning:

&gt; warning xUnit2013: Do not use Assert.Equal() to check for collection size.

However, no alternative is suggested in the warning, and a google search takes me to the source code in xUnit for the test that verifies this warning is printed.

If `Assert.Equal()` isn&#39;t the correct way to verify the length of a collection, what is?

---

To clarify: I realize that I could &quot;trick&quot; xUnit into not emitting this warning by e.g. extracting a variable or using `Assert.True(stuff.Count() == 1)` instead. The latter is just hacky, and the former feels like if xUnit is e.g. trying to avoid multiple iterations of an `IEnumerable&lt;T&gt;`, then this is the wrong way to go (because I&#39;ll get compiler hints about that separately if it&#39;s an issue), and xUnit itself should never have to evaluate the input more than once (in fact it probably will get the same input regardless of variable extraction, because of how C# function calling works).

So, I&#39;m not just interested in removing that warning from my output. An answer to my question also explains *why* that warning is included in the library in the first place and *why* whatever approach I should use instead is better.

What&#39;s the idiomatic way to verify collection size in xUnit?

I have a simple dotnet core class library with a single XUnit test method:

    TestLib.csproj:
    &lt;Project Sdk=&quot;Microsoft.NET.Sdk&quot;&gt;
    
      &lt;PropertyGroup&gt;
        &lt;TargetFramework&gt;netstandard2.0&lt;/TargetFramework&gt;
      &lt;/PropertyGroup&gt;
    
      &lt;ItemGroup&gt;
        &lt;PackageReference Include=&quot;Microsoft.NET.Test.SDK&quot; Version=&quot;15.9.0&quot; /&gt;
        &lt;PackageReference Include=&quot;xunit&quot; Version=&quot;2.4.1&quot; /&gt;
        &lt;PackageReference Include=&quot;xunit.runner.console&quot; Version=&quot;2.4.1&quot;&gt;
          &lt;IncludeAssets&gt;runtime; build; native; contentfiles; analyzers&lt;/IncludeAssets&gt;
          &lt;PrivateAssets&gt;all&lt;/PrivateAssets&gt;
        &lt;/PackageReference&gt;
        &lt;PackageReference Include=&quot;xunit.runner.visualstudio&quot; Version=&quot;2.4.1&quot;&gt;
          &lt;IncludeAssets&gt;runtime; build; native; contentfiles; analyzers&lt;/IncludeAssets&gt;
          &lt;PrivateAssets&gt;all&lt;/PrivateAssets&gt;
        &lt;/PackageReference&gt;
        &lt;PackageReference Include=&quot;xunit.runners&quot; Version=&quot;2.0.0&quot; /&gt;
      &lt;/ItemGroup&gt;
    
    &lt;/Project&gt;

    BasicTest.cs:
    using Xunit;
    
    namespace TestLib
    {
        public class BasicTest
        {
            [Fact(DisplayName = &quot;Basic unit test&quot;)]
            [Trait(&quot;Category&quot;, &quot;unit&quot;)]
            public void TestStringHelper()
            {
                var sut = &quot;sut&quot;;
                var verify = &quot;sut&quot;;
    
                Assert.Equal(sut, verify);
            }
        }
    }

If I enter the project on the CLI and type `dotnet build` the project builds. If I type `dotnet test` I get this:

    C:\git\Testing\TestLib&gt; dotnet test
    C:\git\Testing\TestLib\TestLib.csproj : warning NU1701: Package &#39;xunit.runner.visualstudio 2.4.1&#39; was restored using &#39;.NETFramework,Version=v4.6.1&#39; instead of the project target framework &#39;.NETStandard,Version=v2.0&#39;. This package may not be fully compatible with your project.
    Build started, please wait...
    C:\git\Testing\TestLib\TestLib.csproj : warning NU1701: Package &#39;xunit.runner.visualstudio 2.4.1&#39; was restored using &#39;.NETFramework,Version=v4.6.1&#39; instead of the project target framework &#39;.NETStandard,Version=v2.0&#39;. This package may not be fully compatible with your project.
    Build completed.
    
    Test run for C:\git\Testing\TestLib\bin\Debug\netstandard2.0\TestLib.dll(.NETStandard,Version=v2.0)
    Microsoft (R) Test Execution Command Line Tool Version 16.0.0-preview-20181205-02
    Copyright (c) Microsoft Corporation.  All rights reserved.
    
    Starting test execution, please wait...
    Unable to find C:\git\Testing\TestLib\bin\Debug\netstandard2.0\testhost.dll. Please publish your test project and retry.
    
    Test Run Aborted.

What do I need to change to get the test to run?

If it helps, VS Code is not displaying the tests in its test explorer, either.

Content Type	Original Author	Original Content on Stackoverflow
Question	Dmitry	View Question on Stackoverflow
Solution 1 - .Net	Ruben Bartelink	View Answer on Stackoverflow
Solution 2 - .Net	Saket Kumar	View Answer on Stackoverflow

xunit Assert.ThrowsAsync() does not work properly?

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