示例#1
0
    public async Task ProcessAsync_ReturnsCachedValue_IfEnabled()
    {
        // Arrange
        var id               = "unique-id";
        var childContent     = "original-child-content";
        var cache            = new MemoryCache(new MemoryCacheOptions());
        var tagHelperContext = GetTagHelperContext(id);
        var tagHelperOutput  = GetTagHelperOutput(
            attributes: new TagHelperAttributeList(),
            childContent: childContent);
        var cacheTagHelper = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            ViewContext = GetViewContext(),
            Enabled     = true
        };

        // Act
        await cacheTagHelper.ProcessAsync(tagHelperContext, tagHelperOutput);

        // Assert
        Assert.Empty(tagHelperOutput.PreContent.GetContent());
        Assert.Empty(tagHelperOutput.PostContent.GetContent());
        Assert.True(tagHelperOutput.IsContentModified);
        Assert.Equal(childContent, tagHelperOutput.Content.GetContent());
    }
示例#2
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    public async Task ProcessAsync_UsesExpiresAfter_ToExpireCacheEntry()
    {
        // Arrange - 1
        var currentTime   = new DateTimeOffset(2010, 1, 1, 0, 0, 0, TimeSpan.Zero);
        var id            = "unique-id";
        var childContent1 = "original-child-content";
        var clock         = new Mock <ISystemClock>();

        clock.SetupGet(p => p.UtcNow)
        .Returns(() => currentTime);
        var cache = new MemoryCache(new MemoryCacheOptions {
            Clock = clock.Object
        });
        var tagHelperContext1 = GetTagHelperContext(id);
        var tagHelperOutput1  = GetTagHelperOutput(childContent: childContent1);

        tagHelperOutput1.PreContent.SetContent("<cache>");
        tagHelperOutput1.PostContent.SetContent("</cache>");
        var cacheTagHelper1 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            ViewContext  = GetViewContext(),
            ExpiresAfter = TimeSpan.FromMinutes(10)
        };

        // Act - 1
        await cacheTagHelper1.ProcessAsync(tagHelperContext1, tagHelperOutput1);

        // Assert - 1
        Assert.Empty(tagHelperOutput1.PreContent.GetContent());
        Assert.Empty(tagHelperOutput1.PostContent.GetContent());
        Assert.True(tagHelperOutput1.IsContentModified);
        Assert.Equal(childContent1, tagHelperOutput1.Content.GetContent());

        // Arrange - 2
        var childContent2     = "different-content";
        var tagHelperContext2 = GetTagHelperContext(id);
        var tagHelperOutput2  = GetTagHelperOutput(childContent: childContent2);

        tagHelperOutput2.PreContent.SetContent("<cache>");
        tagHelperOutput2.PostContent.SetContent("</cache>");
        var cacheTagHelper2 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            ViewContext  = GetViewContext(),
            ExpiresAfter = TimeSpan.FromMinutes(10)
        };

        currentTime = currentTime.AddMinutes(11);

        // Act - 2
        await cacheTagHelper2.ProcessAsync(tagHelperContext2, tagHelperOutput2);

        // Assert - 2
        Assert.Empty(tagHelperOutput2.PreContent.GetContent());
        Assert.Empty(tagHelperOutput2.PostContent.GetContent());
        Assert.True(tagHelperOutput2.IsContentModified);
        Assert.Equal(childContent2, tagHelperOutput2.Content.GetContent());
    }
示例#3
0
    public async Task ProcessAsync_RecalculatesValueIfCacheKeyChanges()
    {
        // Arrange - 1
        var id                = "unique-id";
        var childContent1     = "original-child-content";
        var cache             = new MemoryCache(new MemoryCacheOptions());
        var tagHelperContext1 = GetTagHelperContext(id);
        var tagHelperOutput1  = GetTagHelperOutput(childContent: childContent1);

        tagHelperOutput1.PreContent.Append("<cache>");
        tagHelperOutput1.PostContent.SetContent("</cache>");
        var cacheTagHelper1 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            VaryByCookie = "cookie1,cookie2",
            ViewContext  = GetViewContext(),
        };

        cacheTagHelper1.ViewContext.HttpContext.Request.Headers["Cookie"] = "cookie1=value1;cookie2=value2";

        // Act - 1
        await cacheTagHelper1.ProcessAsync(tagHelperContext1, tagHelperOutput1);

        // Assert - 1
        Assert.Empty(tagHelperOutput1.PreContent.GetContent());
        Assert.Empty(tagHelperOutput1.PostContent.GetContent());
        Assert.True(tagHelperOutput1.IsContentModified);
        Assert.Equal(childContent1, tagHelperOutput1.Content.GetContent());

        // Arrange - 2
        var childContent2     = "different-content";
        var tagHelperContext2 = GetTagHelperContext(id);
        var tagHelperOutput2  = GetTagHelperOutput(childContent: childContent2);

        tagHelperOutput2.PreContent.SetContent("<cache>");
        tagHelperOutput2.PostContent.SetContent("</cache>");
        var cacheTagHelper2 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            VaryByCookie = "cookie1,cookie2",
            ViewContext  = GetViewContext(),
        };

        cacheTagHelper2.ViewContext.HttpContext.Request.Headers["Cookie"] = "cookie1=value1;cookie2=not-value2";

        // Act - 2
        await cacheTagHelper2.ProcessAsync(tagHelperContext2, tagHelperOutput2);

        // Assert - 2
        Assert.Empty(tagHelperOutput2.PreContent.GetContent());
        Assert.Empty(tagHelperOutput2.PostContent.GetContent());
        Assert.True(tagHelperOutput2.IsContentModified);
        Assert.Equal(childContent2, tagHelperOutput2.Content.GetContent());
    }
示例#4
0
    public async Task ProcessAsync_ReturnsCachedValue_IfVaryByParamIsUnchanged()
    {
        // Arrange - 1
        var id                = "unique-id";
        var childContent      = "original-child-content";
        var cache             = new MemoryCache(new MemoryCacheOptions());
        var tagHelperContext1 = GetTagHelperContext(id);
        var tagHelperOutput1  = GetTagHelperOutput(
            attributes: new TagHelperAttributeList(),
            childContent: childContent);
        var cacheTagHelper1 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            VaryByQuery = "key1,key2",
            ViewContext = GetViewContext(),
        };

        cacheTagHelper1.ViewContext.HttpContext.Request.QueryString = new QueryString(
            "?key1=value1&key2=value2");

        // Act - 1
        await cacheTagHelper1.ProcessAsync(tagHelperContext1, tagHelperOutput1);

        // Assert - 1
        Assert.Empty(tagHelperOutput1.PreContent.GetContent());
        Assert.Empty(tagHelperOutput1.PostContent.GetContent());
        Assert.True(tagHelperOutput1.IsContentModified);
        Assert.Equal(childContent, tagHelperOutput1.Content.GetContent());

        // Arrange - 2
        var tagHelperContext2 = GetTagHelperContext(id);
        var tagHelperOutput2  = GetTagHelperOutput(
            attributes: new TagHelperAttributeList(),
            childContent: "different-content");
        var cacheTagHelper2 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            VaryByQuery = "key1,key2",
            ViewContext = GetViewContext(),
        };

        cacheTagHelper2.ViewContext.HttpContext.Request.QueryString = new QueryString(
            "?key1=value1&key2=value2");

        // Act - 2
        await cacheTagHelper2.ProcessAsync(tagHelperContext2, tagHelperOutput2);

        // Assert - 2
        Assert.Empty(tagHelperOutput2.PreContent.GetContent());
        Assert.Empty(tagHelperOutput2.PostContent.GetContent());
        Assert.True(tagHelperOutput2.IsContentModified);
        Assert.Equal(childContent, tagHelperOutput2.Content.GetContent());
    }
示例#5
0
    public async Task ProcessAsync_SetsEntrySize_ForPlaceholderAndFinalCacheEntries()
    {
        // Arrange
        var mockCache = new Mock <IMemoryCache>();
        var tempEntry = new Mock <ICacheEntry>();

        tempEntry.SetupAllProperties();
        tempEntry.Setup(e => e.ExpirationTokens).Returns(new List <IChangeToken>());
        tempEntry.Setup(e => e.PostEvictionCallbacks).Returns(new List <PostEvictionCallbackRegistration>());
        var finalEntry = new Mock <ICacheEntry>();

        finalEntry.SetupAllProperties();
        finalEntry.Setup(e => e.ExpirationTokens).Returns(new List <IChangeToken>());
        finalEntry.Setup(e => e.PostEvictionCallbacks).Returns(new List <PostEvictionCallbackRegistration>());
        object value;

        mockCache
        .Setup(s => s.TryGetValue(It.IsAny <object>(), out value))
        .Returns(false);

        mockCache.SetupSequence(mc => mc.CreateEntry(It.IsAny <object>()))
        .Returns(tempEntry.Object)
        .Returns(finalEntry.Object);

        var id                = "unique-id";
        var childContent1     = "original-child-content";
        var tagHelperContext1 = GetTagHelperContext(id);
        var tagHelperOutput1  = GetTagHelperOutput(childContent: childContent1);

        tagHelperOutput1.PreContent.Append("<cache>");
        tagHelperOutput1.PostContent.SetContent("</cache>");
        var cacheTagHelper1 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(mockCache.Object), new HtmlTestEncoder())
        {
            ViewContext = GetViewContext(),
        };

        // Act
        await cacheTagHelper1.ProcessAsync(tagHelperContext1, tagHelperOutput1);

        // Assert
        Assert.Empty(tagHelperOutput1.PreContent.GetContent());
        Assert.Empty(tagHelperOutput1.PostContent.GetContent());
        Assert.True(tagHelperOutput1.IsContentModified);
        Assert.Equal(childContent1, tagHelperOutput1.Content.GetContent());
        tempEntry.VerifySet(e => e.Size  = 64);
        finalEntry.VerifySet(e => e.Size = childContent1.Length * 2);
    }
示例#6
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    public async Task ProcessAsync_WorksForNestedCacheTagHelpers()
    {
        // Arrange
        var expected        = "Hello world";
        var cache           = new MemoryCache(new MemoryCacheOptions());
        var encoder         = new HtmlTestEncoder();
        var cacheTagHelper1 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), encoder)
        {
            ViewContext = GetViewContext(),
            Enabled     = true
        };

        var cacheTagHelper2 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), encoder)
        {
            ViewContext = GetViewContext(),
            Enabled     = true
        };

        var tagHelperOutput2 = new TagHelperOutput(
            "cache",
            new TagHelperAttributeList(),
            getChildContentAsync: (useCachedResult, _) =>
        {
            var content = new DefaultTagHelperContent();
            content.SetContent(expected);
            return(Task.FromResult <TagHelperContent>(content));
        });

        var tagHelperOutput1 = new TagHelperOutput(
            "cache",
            new TagHelperAttributeList(),
            getChildContentAsync: async(useCachedResult, _) =>
        {
            var context = GetTagHelperContext("test2");
            var output  = tagHelperOutput2;
            await cacheTagHelper2.ProcessAsync(context, output);
            return(await output.GetChildContentAsync());
        });

        // Act
        await cacheTagHelper1.ProcessAsync(GetTagHelperContext(), tagHelperOutput1);

        // Assert
        Assert.Equal(encoder.Encode(expected), tagHelperOutput1.Content.GetContent());
    }
示例#7
0
    public async Task ProcessAsync_AwaitersUseTheResultOfExecutor()
    {
        // Arrange
        var expected = "Hello world";
        var cache    = new TestMemoryCache();
        var encoder  = new HtmlTestEncoder();
        // The two instances represent two instances of the same cache tag helper appearance in the page.
        var cacheTagHelper1 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), encoder)
        {
            ViewContext = GetViewContext(),
            Enabled     = true
        };

        var cacheTagHelper2 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), encoder)
        {
            ViewContext = GetViewContext(),
            Enabled     = true
        };

        var invokeCount = 0;

        Func <bool, HtmlEncoder, Task <TagHelperContent> > getChildContentAsync = (useCachedResult, _) =>
        {
            invokeCount++;

            var content = new DefaultTagHelperContent();
            content.SetContent(expected);
            return(Task.FromResult <TagHelperContent>(content));
        };

        var tagHelperOutput1 = new TagHelperOutput("cache", new TagHelperAttributeList(), getChildContentAsync);
        var tagHelperOutput2 = new TagHelperOutput("cache", new TagHelperAttributeList(), getChildContentAsync);

        // Act
        var task1 = Task.Run(() => cacheTagHelper1.ProcessAsync(GetTagHelperContext(cache.Key1), tagHelperOutput1));
        var task2 = Task.Run(() => cacheTagHelper2.ProcessAsync(GetTagHelperContext(cache.Key2), tagHelperOutput2));

        // Assert
        await Task.WhenAll(task1, task2);

        Assert.Equal(1, invokeCount); // We expect getChildContentAsync to be invoked exactly once.
        Assert.Equal(encoder.Encode(expected), tagHelperOutput1.Content.GetContent());
        Assert.Equal(encoder.Encode(expected), tagHelperOutput2.Content.GetContent());
    }
示例#8
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    public async Task ProcessAsync_ThrowsExceptionForAwaiters_IfExecutorEncountersAnException()
    {
        // Arrange
        var expected = new DivideByZeroException();
        var cache    = new TestMemoryCache();
        // The two instances represent two instances of the same cache tag helper appearance in the page.
        var cacheTagHelper1 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            ViewContext = GetViewContext(),
            Enabled     = true
        };
        var cacheTagHelper2 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            ViewContext = GetViewContext(),
            Enabled     = true
        };

        var invokeCount     = 0;
        var tagHelperOutput = new TagHelperOutput(
            "cache",
            new TagHelperAttributeList(),
            getChildContentAsync: (useCachedResult, _) =>
        {
            invokeCount++;
            throw expected;
        });

        // Act
        var task1 = Task.Run(() => cacheTagHelper1.ProcessAsync(GetTagHelperContext(cache.Key1), tagHelperOutput));
        var task2 = Task.Run(() => cacheTagHelper2.ProcessAsync(GetTagHelperContext(cache.Key2), tagHelperOutput));

        // Assert
        await Assert.ThrowsAsync <DivideByZeroException>(() => task1);

        await Assert.ThrowsAsync <DivideByZeroException>(() => task2);

        Assert.Equal(1, invokeCount);
    }
示例#9
0
    public async Task ProcessAsync_DoesNotCache_IfDisabled()
    {
        // Arrange
        var id           = "unique-id";
        var childContent = "original-child-content";
        var cache        = new Mock <IMemoryCache>();
        var value        = new Mock <ICacheEntry>();

        value.Setup(c => c.Value).Returns(new DefaultTagHelperContent().SetContent("ok"));
        cache.Setup(c => c.CreateEntry(
                        /*key*/ It.IsAny <string>()))
        .Returns((object key) => value.Object)
        .Verifiable();
        object cacheResult;

        cache.Setup(c => c.TryGetValue(It.IsAny <string>(), out cacheResult))
        .Returns(false);
        var tagHelperContext = GetTagHelperContext(id);
        var tagHelperOutput  = GetTagHelperOutput(
            attributes: new TagHelperAttributeList(),
            childContent: childContent);
        var cacheTagHelper = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache.Object), new HtmlTestEncoder())
        {
            ViewContext = GetViewContext(),
            Enabled     = false
        };

        // Act
        await cacheTagHelper.ProcessAsync(tagHelperContext, tagHelperOutput);

        // Assert
        Assert.Equal(childContent, tagHelperOutput.Content.GetContent());
        cache.Verify(c => c.CreateEntry(
                         /*key*/ It.IsAny <string>()),
                     Times.Never);
    }
示例#10
0
    public async Task ProcessAsync_ExceptionInProcessing_DoNotThrowInSubsequentRequests()
    {
        // Arrange
        var id           = "unique-id";
        var childContent = "some-content";
        var cache        = new MemoryCache(new MemoryCacheOptions());

        var counter = 0;

        Task <TagHelperContent> GetChildContentAsync(bool useCachedResult, HtmlEncoder encoder)
        {
            counter++;
            if (counter < 3)
            {
                // throw on first two calls
                throw new Exception();
            }
            else
            {
                // produce content on third call
                var tagHelperContent = new DefaultTagHelperContent();
                tagHelperContent.SetHtmlContent(childContent);
                return(Task.FromResult <TagHelperContent>(tagHelperContent));
            }
        }

        var tagHelperContext1 = GetTagHelperContext(id);
        var tagHelperContext2 = GetTagHelperContext(id);
        var tagHelperContext3 = GetTagHelperContext(id);
        var tagHelperContext4 = GetTagHelperContext(id);

        var tagHelperOutput1 = new TagHelperOutput("cache", new TagHelperAttributeList(), GetChildContentAsync);
        var tagHelperOutput2 = new TagHelperOutput("cache", new TagHelperAttributeList(), GetChildContentAsync);
        var tagHelperOutput3 = new TagHelperOutput("cache", new TagHelperAttributeList(), GetChildContentAsync);
        var tagHelperOutput4 = new TagHelperOutput("cache", new TagHelperAttributeList(), GetChildContentAsync);

        var cacheTagHelper = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            ViewContext  = GetViewContext(),
            Enabled      = true,
            ExpiresAfter = TimeSpan.FromHours(1.0)
        };

        // Act - 1

        await Assert.ThrowsAsync <Exception>(() => cacheTagHelper.ProcessAsync(tagHelperContext1, tagHelperOutput1));

        // Assert - 1

        Assert.Equal(1, counter);
        Assert.Empty(tagHelperOutput1.PreContent.GetContent());
        Assert.Empty(tagHelperOutput1.PostContent.GetContent());
        Assert.False(tagHelperOutput1.IsContentModified);
        Assert.Empty(tagHelperOutput1.Content.GetContent());

        // Act - 2

        await Assert.ThrowsAsync <Exception>(() => cacheTagHelper.ProcessAsync(tagHelperContext2, tagHelperOutput2));

        // Assert - 2

        Assert.Equal(2, counter);
        Assert.Empty(tagHelperOutput2.PreContent.GetContent());
        Assert.Empty(tagHelperOutput2.PostContent.GetContent());
        Assert.False(tagHelperOutput2.IsContentModified);
        Assert.Empty(tagHelperOutput2.Content.GetContent());

        // Act - 3

        await cacheTagHelper.ProcessAsync(tagHelperContext3, tagHelperOutput3);

        // Assert - 3

        Assert.Equal(3, counter);
        Assert.Empty(tagHelperOutput3.PreContent.GetContent());
        Assert.Empty(tagHelperOutput3.PostContent.GetContent());
        Assert.True(tagHelperOutput3.IsContentModified);
        Assert.Equal(childContent, tagHelperOutput3.Content.GetContent());

        // Act - 4

        await cacheTagHelper.ProcessAsync(tagHelperContext4, tagHelperOutput4);

        // Assert - 4

        Assert.Equal(3, counter);
        Assert.Empty(tagHelperOutput4.PreContent.GetContent());
        Assert.Empty(tagHelperOutput4.PostContent.GetContent());
        Assert.True(tagHelperOutput4.IsContentModified);
        Assert.Equal(childContent, tagHelperOutput4.Content.GetContent());
    }
示例#11
0
    public async Task ProcessAsync_ExceptionInProcessing_DoesntBlockConcurrentRequests()
    {
        // Arrange
        var id           = "unique-id";
        var childContent = "some-content";
        var event1       = new TaskCompletionSource <int>(TaskCreationOptions.RunContinuationsAsynchronously);
        var event2       = new TaskCompletionSource <int>(TaskCreationOptions.RunContinuationsAsynchronously);
        var event3       = new TaskCompletionSource <int>(TaskCreationOptions.RunContinuationsAsynchronously);
        var calls        = 0;
        var cache        = new MemoryCache(new MemoryCacheOptions());

        var tagHelperContext1 = GetTagHelperContext(id + 1);
        var tagHelperContext2 = GetTagHelperContext(id + 2);

        var tagHelperOutput1 = new TagHelperOutput(
            "cache",
            new TagHelperAttributeList(),
            getChildContentAsync: (useCachedResult, encoder) =>
        {
            calls++;
            event2.SetResult(0);

            throw new Exception();
        });

        var tagHelperOutput2 = new TagHelperOutput(
            "cache",
            new TagHelperAttributeList(),
            getChildContentAsync: async(useCachedResult, encoder) =>
        {
            calls++;
            await event3.Task.TimeoutAfter(TimeSpan.FromSeconds(5));

            var tagHelperContent = new DefaultTagHelperContent();
            tagHelperContent.SetHtmlContent(childContent);
            return(tagHelperContent);
        });

        var cacheTagHelper1 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            ViewContext = GetViewContext(),
            Enabled     = true
        };

        var cacheTagHelper2 = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            ViewContext = GetViewContext(),
            Enabled     = true
        };

        // Act

        var task1 = Task.Run(async() =>
        {
            await event1.Task.TimeoutAfter(TimeSpan.FromSeconds(5));
            await Assert.ThrowsAsync <Exception>(() => cacheTagHelper1.ProcessAsync(tagHelperContext1, tagHelperOutput1));
            event3.SetResult(0);
        });

        var task2 = Task.Run(async() =>
        {
            await event2.Task.TimeoutAfter(TimeSpan.FromSeconds(5));
            await cacheTagHelper2.ProcessAsync(tagHelperContext2, tagHelperOutput2);
        });

        event1.SetResult(0);
        await Task.WhenAll(task1, task2);

        // Assert
        Assert.Empty(tagHelperOutput1.PreContent.GetContent());
        Assert.Empty(tagHelperOutput1.PostContent.GetContent());
        Assert.False(tagHelperOutput1.IsContentModified);
        Assert.Empty(tagHelperOutput1.Content.GetContent());

        Assert.Empty(tagHelperOutput2.PreContent.GetContent());
        Assert.Empty(tagHelperOutput2.PostContent.GetContent());
        Assert.True(tagHelperOutput2.IsContentModified);
        Assert.Equal(childContent, tagHelperOutput2.Content.GetContent());

        Assert.Equal(2, calls);
    }
示例#12
0
    public async Task ProcessAsync_FlowsEntryLinkThatAllowsAddingTriggersToAddedEntry()
    {
        // Arrange
        var id = "some-id";
        var expectedContent = new DefaultTagHelperContent();

        expectedContent.SetContent("some-content");
        var tokenSource = new CancellationTokenSource();
        var cache       = new MemoryCache(new MemoryCacheOptions()
        {
            TrackLinkedCacheEntries = true
        });
        var cacheEntryOptions = new MemoryCacheEntryOptions()
                                .AddExpirationToken(new CancellationChangeToken(tokenSource.Token));
        var tagHelperContext = new TagHelperContext(
            tagName: "cache",
            allAttributes: new TagHelperAttributeList(),
            items: new Dictionary <object, object>(),
            uniqueId: id);
        var tagHelperOutput = new TagHelperOutput(
            "cache",
            new TagHelperAttributeList {
            { "attr", "value" }
        },
            getChildContentAsync: (useCachedResult, encoder) =>
        {
            if (!cache.TryGetValue("key1", out TagHelperContent tagHelperContent))
            {
                tagHelperContent = expectedContent;
                cache.Set("key1", tagHelperContent, cacheEntryOptions);
            }

            return(Task.FromResult(tagHelperContent));
        });

        tagHelperOutput.PreContent.SetContent("<cache>");
        tagHelperOutput.PostContent.SetContent("</cache>");
        var cacheTagHelper = new CacheTagHelper(new CacheTagHelperMemoryCacheFactory(cache), new HtmlTestEncoder())
        {
            ViewContext = GetViewContext(),
        };

        var cacheTagKey = new CacheTagKey(cacheTagHelper, tagHelperContext);
        var key         = cacheTagKey.GenerateKey();

        // Act - 1
        await cacheTagHelper.ProcessAsync(tagHelperContext, tagHelperOutput);

        var result = cache.TryGetValue(cacheTagKey, out Task <IHtmlContent> cachedValue);

        // Assert - 1
        Assert.Equal("HtmlEncode[[some-content]]", tagHelperOutput.Content.GetContent());
        Assert.True(result);

        // Act - 2
        tokenSource.Cancel();
        result = cache.TryGetValue(cacheTagKey, out cachedValue);

        // Assert - 2
        Assert.False(result);
        Assert.Null(cachedValue);
    }