Reduce allocations in System.Text.Json tests and catch OOM exceptions

dotnet · Jul 21, 2023 · 58375c9 · 58375c9
1 parent e357352
commit 58375c9
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Showing 6 changed files with 397 additions and 341 deletions.
diff --git a/src/libraries/System.Text.Json/tests/System.Text.Json.Tests/JsonEncodedTextTests.cs b/src/libraries/System.Text.Json/tests/System.Text.Json.Tests/JsonEncodedTextTests.cs
@@ -4,6 +4,7 @@
 using System.Collections.Generic;
 using System.Text.Encodings.Web;
 using System.Text.Unicode;
+using Microsoft.DotNet.XUnitExtensions;
 using Xunit;
 
 namespace System.Text.Json.Tests
@@ -235,7 +236,7 @@ public static void ToStringLargeTest(int stringLength)
             }
             {
                 var message = new string('>', stringLength);
-                var builder = new StringBuilder();
+                var builder = new StringBuilder(stringLength);
                 for (int i = 0; i < stringLength; i++)
                 {
                     builder.Append("\\u003E");
@@ -302,7 +303,7 @@ public static void GetUtf8BytesLargeTest(int stringLength)
             }
             {
                 var message = new string('>', stringLength);
-                var builder = new StringBuilder();
+                var builder = new StringBuilder(stringLength);
                 for (int i = 0; i < stringLength; i++)
                 {
                     builder.Append("\\u003E");
@@ -362,7 +363,7 @@ public static void GetValueLargeTest(int stringLength)
         public static void GetValueLargeEscapedTest(int stringLength)
         {
             var message = new string('>', stringLength);
-            var builder = new StringBuilder();
+            var builder = new StringBuilder(stringLength);
             for (int i = 0; i < stringLength; i++)
             {
                 builder.Append("\\u003E");
@@ -426,7 +427,7 @@ public static void InvalidLargeEncode()
             }
             catch (OutOfMemoryException)
             {
-                return;
+                throw new SkipTestException("Out of memory allocating large objects");
             }
         }
 

diff --git a/...ibraries/System.Text.Json/tests/System.Text.Json.Tests/Serialization/Object.WriteTests.cs b/...ibraries/System.Text.Json/tests/System.Text.Json.Tests/Serialization/Object.WriteTests.cs
@@ -5,6 +5,7 @@
 using System.Linq;
 using System.Text.Encodings.Web;
 using System.Text.Json.Tests;
+using Microsoft.DotNet.XUnitExtensions;
 using Xunit;
 
 namespace System.Text.Json.Serialization.Tests
@@ -161,42 +162,49 @@ public static void WriteObjectWithNumberHandling()
         [OuterLoop]
         public static void SerializeLargeListOfObjects()
         {
-            Dto dto = new()
-            {
-                Prop1 = int.MaxValue,
-                Prop2 = int.MinValue,
-                Prop3 = "AC",
-                Prop4 = 500,
-                Prop5 = int.MaxValue / 2,
-                Prop6 = 250M,
-                Prop7 = 250M,
-                Prop8 = 250M,
-                Prop9 = 250M,
-                Prop10 = 250M,
-                Prop11 = 150M,
-                Prop12 = 150M,
-                Prop13 = DateTimeOffset.MaxValue,
-                Prop14 = DateTimeOffset.MaxValue,
-                Prop15 = DateTimeOffset.MaxValue,
-                Prop16 = DateTimeOffset.MaxValue,
-                Prop17 = 3,
-                Prop18 = DateTime.MaxValue,
-                Prop19 = DateTime.MaxValue,
-                Prop20 = 25000,
-                Prop21 = DateTime.MaxValue
-            };
-
-            // It takes a little over 4,338,000 items to reach a payload size above the Array.MaxLength value.
-            List<Dto> items = Enumerable.Repeat(dto, 4_338_000).ToList();
-
             try
             {
-                JsonSerializer.SerializeToUtf8Bytes(items);
+                Dto dto = new()
+                {
+                    Prop1 = int.MaxValue,
+                    Prop2 = int.MinValue,
+                    Prop3 = "AC",
+                    Prop4 = 500,
+                    Prop5 = int.MaxValue / 2,
+                    Prop6 = 250M,
+                    Prop7 = 250M,
+                    Prop8 = 250M,
+                    Prop9 = 250M,
+                    Prop10 = 250M,
+                    Prop11 = 150M,
+                    Prop12 = 150M,
+                    Prop13 = DateTimeOffset.MaxValue,
+                    Prop14 = DateTimeOffset.MaxValue,
+                    Prop15 = DateTimeOffset.MaxValue,
+                    Prop16 = DateTimeOffset.MaxValue,
+                    Prop17 = 3,
+                    Prop18 = DateTime.MaxValue,
+                    Prop19 = DateTime.MaxValue,
+                    Prop20 = 25000,
+                    Prop21 = DateTime.MaxValue
+                };
+
+                // It takes a little over 4,338,000 items to reach a payload size above the Array.MaxLength value.
+                List<Dto> items = Enumerable.Repeat(dto, 4_338_000).ToList();
+
+                try
+                {
+                    JsonSerializer.SerializeToUtf8Bytes(items);
+                }
+                catch (OutOfMemoryException) { }
+
+                items.AddRange(Enumerable.Repeat(dto, 1000).ToList());
+                Assert.Throws<OutOfMemoryException>(() => JsonSerializer.SerializeToUtf8Bytes(items));
+            }
+            catch (OutOfMemoryException)
+            {
+                throw new SkipTestException("Out of memory allocating large objects");
             }
-            catch (OutOfMemoryException) { }
-
-            items.AddRange(Enumerable.Repeat(dto, 1000).ToList());
-            Assert.Throws<OutOfMemoryException>(() => JsonSerializer.SerializeToUtf8Bytes(items));
         }
 
         class Dto

diff --git a/src/libraries/System.Text.Json/tests/System.Text.Json.Tests/Serialization/Value.ReadTests.cs b/src/libraries/System.Text.Json/tests/System.Text.Json.Tests/Serialization/Value.ReadTests.cs
@@ -4,6 +4,7 @@
 using System.Collections.Generic;
 using System.Globalization;
 using System.Runtime.CompilerServices;
+using Microsoft.DotNet.XUnitExtensions;
 using Newtonsoft.Json;
 using Xunit;
 
@@ -453,8 +454,15 @@ public static void LongInputString(int length)
         [OuterLoop]
         public static void VeryLongInputString(int length)
         {
-            // Verify that deserializer does not do any multiplication or addition on the string length
-            DeserializeLongJsonString(length);
+            try
+            {
+                // Verify that deserializer does not do any multiplication or addition on the string length
+                DeserializeLongJsonString(length);
+            }
+            catch (OutOfMemoryException)
+            {
+                throw new SkipTestException("Out of memory allocating large objects");
+            }
         }
 
         private static void DeserializeLongJsonString(int stringLength)

diff --git a/src/libraries/System.Text.Json/tests/System.Text.Json.Tests/Utf8JsonReaderTests.cs b/src/libraries/System.Text.Json/tests/System.Text.Json.Tests/Utf8JsonReaderTests.cs
@@ -3038,7 +3038,7 @@ public static void JsonContainingOnlyCommentsIsInvalid(string jsonString, int ex
         [MemberData(nameof(LotsOfCommentsTests))]
         public static void SkipLotsOfComments(string valueString, bool insideArray, string expectedString)
         {
-            var builder = new StringBuilder();
+            var builder = new StringBuilder(2_000_000);
             if (insideArray)
             {
                 builder.Append("[");
@@ -3116,7 +3116,7 @@ public static void SkipLotsOfComments(string valueString, bool insideArray, stri
         [MemberData(nameof(LotsOfCommentsTests))]
         public static void ConsumeLotsOfComments(string valueString, bool insideArray, string expectedString)
         {
-            var builder = new StringBuilder();
+            var builder = new StringBuilder(2_000_000);
             if (insideArray)
             {
                 builder.Append("[");