chore: Expect event sink to match predicate.

launchdarkly · May 28, 2024 · b4f44f1 · b4f44f1
1 parent 881c064
commit b4f44f1
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Showing 2 changed files with 30 additions and 6 deletions.
diff --git a/pkgs/sdk/server/test/AssertHelpers.cs b/pkgs/sdk/server/test/AssertHelpers.cs
@@ -1,4 +1,6 @@
-using LaunchDarkly.Logging;
+using System;
+using LaunchDarkly.Logging;
+using LaunchDarkly.TestHelpers;
 using Xunit;
 using Xunit.Sdk;
 
@@ -42,5 +44,24 @@ private static void ThrowLogMatchException(LogCapture logCapture, bool shouldHav
                     text,
                     level,
                     logCapture.ToString()));
+
+        public static void ExpectPredicate<T>(EventSink<T> sink, Predicate<T> predicate, string message, TimeSpan timeout)
+        {
+            while (true)
+            {
+                var startTime = DateTimeOffset.Now.ToUnixTimeMilliseconds();
+                var value = sink.ExpectValue();
+                if (predicate(value))
+                {
+                    break;
+                }
+
+                if (DateTimeOffset.Now.ToUnixTimeMilliseconds() - startTime > timeout.TotalMilliseconds)
+                {
+                    // XUnit 2.5+ adds Assert.Fail.
+                    Assert.True(false, message);
+                }
+            }
+        }
     }
 }
diff --git a/pkgs/sdk/server/test/Internal/DataSources/FileDataSourceTest.cs b/pkgs/sdk/server/test/Internal/DataSources/FileDataSourceTest.cs
@@ -8,7 +8,6 @@
 using YamlDotNet.Serialization;
 using Xunit;
 using Xunit.Abstractions;
-
 using static LaunchDarkly.Sdk.Server.Subsystems.DataStoreTypes;
 using static LaunchDarkly.Sdk.Server.TestUtils;
 using static LaunchDarkly.TestHelpers.JsonAssertions;
@@ -24,7 +23,9 @@ public class FileDataSourceTest : BaseTest
         private readonly FileDataSourceBuilder factory = FileData.DataSource();
         private readonly Context user = Context.New("key");
 
-        public FileDataSourceTest(ITestOutputHelper testOutput) : base(testOutput) { }
+        public FileDataSourceTest(ITestOutputHelper testOutput) : base(testOutput)
+        {
+        }
 
         private IDataSource MakeDataSource() =>
             factory.Build(BasicContext.WithDataSourceUpdates(_updateSink));
@@ -148,9 +149,11 @@ public void ModifiedFileIsReloadedIfAutoUpdateIsOn()
 
                     file.SetContentFromPath(TestUtils.TestFilePath("segment-only.json"));
 
-                    var newData = _updateSink.Inits.ExpectValue(TimeSpan.FromSeconds(5));
-
-                    AssertJsonEqual(DataSetAsJson(ExpectedDataSetForSegmentOnlyFile(2)), DataSetAsJson(newData));
+                    var expectedDataSet = DataSetAsJson(ExpectedDataSetForSegmentOnlyFile(2));
+                    AssertHelpers.ExpectPredicate(_updateSink.Inits, actual =>
+                            expectedDataSet.Equals(DataSetAsJson(actual)),
+                        "Did not receive expected update from the file data source.",
+                        TimeSpan.FromSeconds(5));
                 }
             }
         }