♻️🧪Use CultureScope in tests to revert CurrentCulture changes

Use `CultureScope` instead of try-catch, simpler syntax.
Add `CultureScope` to some test cases that previously did not revert their changes to CurrentCulture, to avoid flaky tests.

Author: angularsen

CodeGen/Generators/UnitsNetGen/UnitTestBaseClassGenerator.cs

@@ -597,20 +597,13 @@ public void BaseDimensionsShouldNeverBeNull()
         [Fact]
         public void ToString_ReturnsValueAndUnitAbbreviationInCurrentCulture()
         {{
-            var prevCulture = Thread.CurrentThread.CurrentCulture;
-            Thread.CurrentThread.CurrentCulture = CultureInfo.GetCultureInfo(""en-US"");
-            try {{");
+            using var _ = new CultureScope(""en-US"");");
             foreach (var unit in _quantity.Units)
             {
                 Writer.WL($@"
-                Assert.Equal(""1{GetEnglishAbbreviation(unit)}"", new {_quantity.Name}(1, {GetUnitFullName(unit)}).ToString());");
+            Assert.Equal(""1{GetEnglishAbbreviation(unit)}"", new {_quantity.Name}(1, {GetUnitFullName(unit)}).ToString());");
             }
             Writer.WL($@"
-            }}
-            finally
-            {{
-                Thread.CurrentThread.CurrentCulture = prevCulture;
-            }}
         }}
 
         [Fact]
@@ -630,19 +623,11 @@ public void ToString_WithSwedishCulture_ReturnsUnitAbbreviationForEnglishCulture
         [Fact]
         public void ToString_SFormat_FormatsNumberWithGivenDigitsAfterRadixForCurrentCulture()
         {{
-            var oldCulture = CultureInfo.CurrentCulture;
-            try
-            {{
-                CultureInfo.CurrentCulture = CultureInfo.InvariantCulture;
-                Assert.Equal(""0.1{_baseUnitEnglishAbbreviation}"", new {_quantity.Name}(0.123456{_numberSuffix}, {_baseUnitFullName}).ToString(""s1""));
-                Assert.Equal(""0.12{_baseUnitEnglishAbbreviation}"", new {_quantity.Name}(0.123456{_numberSuffix}, {_baseUnitFullName}).ToString(""s2""));
-                Assert.Equal(""0.123{_baseUnitEnglishAbbreviation}"", new {_quantity.Name}(0.123456{_numberSuffix}, {_baseUnitFullName}).ToString(""s3""));
-                Assert.Equal(""0.1235{_baseUnitEnglishAbbreviation}"", new {_quantity.Name}(0.123456{_numberSuffix}, {_baseUnitFullName}).ToString(""s4""));
-            }}
-            finally
-            {{
-                CultureInfo.CurrentCulture = oldCulture;
-            }}
+            var _ = new CultureScope(CultureInfo.InvariantCulture);
+            Assert.Equal(""0.1{_baseUnitEnglishAbbreviation}"", new {_quantity.Name}(0.123456{_numberSuffix}, {_baseUnitFullName}).ToString(""s1""));
+            Assert.Equal(""0.12{_baseUnitEnglishAbbreviation}"", new {_quantity.Name}(0.123456{_numberSuffix}, {_baseUnitFullName}).ToString(""s2""));
+            Assert.Equal(""0.123{_baseUnitEnglishAbbreviation}"", new {_quantity.Name}(0.123456{_numberSuffix}, {_baseUnitFullName}).ToString(""s3""));
+            Assert.Equal(""0.1235{_baseUnitEnglishAbbreviation}"", new {_quantity.Name}(0.123456{_numberSuffix}, {_baseUnitFullName}).ToString(""s4""));
         }}
 
         [Fact]

README.md

@@ -98,7 +98,7 @@ var oneKg = Mass.FromKilograms(1);
 
 // ToString() uses CurrentCulture for abbreviation language number formatting. This is consistent with the behavior of the .NET Framework,
 // where DateTime.ToString() uses CurrentCulture for the whole string, likely because mixing an english date format with a russian month name might be confusing.
-Thread.CurrentThread.CurrentCulture = russian;
+CultureInfo.CurrentCulture = russian;
 string kgRu = oneKg.ToString(); // "1 кг"
 
 // ToString() with specific culture and custom string format pattern
@@ -362,7 +362,7 @@ double convertedValue = UnitConverter.Convert(
 ### Example: WPF app using IValueConverter to parse input
 
 Src: [Samples/MvvmSample.Wpf](https://github.com/angularsen/UnitsNet/tree/master/Samples/MvvmSample.Wpf)
-                             
+
 ![wpfmvvmsample_219w](https://user-images.githubusercontent.com/787816/34913417-094332e2-f8fd-11e7-9d8a-92db105fbbc9.png)
 
 The purpose of this app is to show how to create an `IValueConverter` in order to bind XAML to quantities.

UnitsNet.Tests/CustomCode/StonePoundsTests.cs

@@ -2,6 +2,7 @@
 // Copyright 2013 Andreas Gullberg Larsen ([email protected]). Maintained at https://github.com/angularsen/UnitsNet.
 
 using System.Globalization;
+using UnitsNet.Tests.Helpers;
 using Xunit;
 
 namespace UnitsNet.Tests
@@ -33,7 +34,7 @@ public void StonePoundsRoundTrip()
         [Fact]
         public void StonePoundsToString_FormatsNumberInCurrentCulture()
         {
-            CultureInfo.CurrentCulture = CultureInfo.GetCultureInfo("en-US");
+            using var _ = new CultureScope("en-US");
             StonePounds stonePounds = Mass.FromStonePounds(3500, 1).StonePounds;
 
             Assert.Equal("3,500 st 1 lb", stonePounds.ToString());

UnitsNet.Tests/Helpers/CultureScope.cs

@@ -0,0 +1,36 @@
+// Licensed under MIT No Attribution, see LICENSE file at the root.
+// Copyright 2013 Andreas Gullberg Larsen ([email protected]). Maintained at https://github.com/angularsen/UnitsNet.
+
+using System;
+using System.Globalization;
+
+namespace UnitsNet.Tests.Helpers;
+
+public sealed class CultureScope : IDisposable
+{
+    private readonly CultureInfo _originalCulture;
+    private readonly CultureInfo _originalUiCulture;
+
+    public CultureScope(string cultureName) : this(CultureInfo.GetCultureInfo(cultureName))
+    {
+    }
+
+    public CultureScope(CultureInfo culture) : this(culture, culture)
+    {
+    }
+
+    public CultureScope(CultureInfo culture, CultureInfo uiCulture)
+    {
+        _originalCulture = CultureInfo.CurrentCulture;
+        _originalUiCulture = CultureInfo.CurrentUICulture;
+
+        CultureInfo.CurrentCulture = culture;
+        CultureInfo.CurrentUICulture = uiCulture;
+    }
+
+    public void Dispose()
+    {
+        CultureInfo.CurrentCulture = _originalCulture;
+        CultureInfo.CurrentUICulture = _originalUiCulture;
+    }
+}

UnitsNet.Tests/QuantityTests.ToString.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Globalization;
+using UnitsNet.Tests.Helpers;
 using UnitsNet.Units;
 using Xunit;
 
@@ -31,18 +32,10 @@ public void ReturnsTheOriginalValueAndUnit()
             [Fact]
             public void FormatsNumberUsingGivenCulture()
             {
-                var oldCulture = CultureInfo.CurrentCulture;
-                try
-                {
-                    CultureInfo.CurrentCulture = CultureInfo.InvariantCulture;
-                    Assert.Equal("0.05 m", Length.FromCentimeters(5).ToUnit(LengthUnit.Meter).ToString((IFormatProvider?)null));
-                    Assert.Equal("0.05 m", Length.FromCentimeters(5).ToUnit(LengthUnit.Meter).ToString(CultureInfo.InvariantCulture));
-                    Assert.Equal("0,05 m", Length.FromCentimeters(5).ToUnit(LengthUnit.Meter).ToString(CultureInfo.GetCultureInfo("nb-NO")));
-                }
-                finally
-                {
-                    CultureInfo.CurrentCulture = oldCulture;
-                }
+                using var _ = new CultureScope(CultureInfo.InvariantCulture);
+                Assert.Equal("0.05 m", Length.FromCentimeters(5).ToUnit(LengthUnit.Meter).ToString((IFormatProvider?)null));
+                Assert.Equal("0.05 m", Length.FromCentimeters(5).ToUnit(LengthUnit.Meter).ToString(CultureInfo.InvariantCulture));
+                Assert.Equal("0,05 m", Length.FromCentimeters(5).ToUnit(LengthUnit.Meter).ToString(CultureInfo.GetCultureInfo("nb-NO")));
             }
         }
     }

UnitsNet.Tests/QuantityTypeConverterTest.cs

@@ -242,11 +242,12 @@ public void ConvertTo_GivenSomeQuantityAndContextWithDisplayAsUnitAttributes_Ret
             });
             Length length = Length.FromMeters(1);
 
-            CultureInfo.CurrentCulture = CultureInfo.GetCultureInfo("en-US");
-
+            // Act
+            using var _ = new CultureScope(Culture);
             string convertedQuantityCurrentCulture = (string)converter.ConvertTo(length, typeof(string))!;
             string convertedQuantitySpecificCulture = (string)converter.ConvertTo(context, Culture, length, typeof(string))!;
 
+            // Assert
             Assert.Equal("1 m", convertedQuantityCurrentCulture);
             Assert.Equal("10 dm", convertedQuantitySpecificCulture);
         }
@@ -259,8 +260,9 @@ public void ConvertTo_GivenCurrentCulture_ReturnValueFormattedAccordingToGivenCu
             QuantityTypeConverter<Length> converter = new();
             var attributes = useDisplayAsAttribute ? new Attribute[] { new DisplayAsUnitAttribute(Units.LengthUnit.Meter) } : Array.Empty<Attribute>();
             ITypeDescriptorContext context = new TypeDescriptorContext("SomeMemberName", attributes);
-            CultureInfo.CurrentCulture = CultureInfo.GetCultureInfo("de-AT"); // uses comma as decimal separator
-            CultureInfo.CurrentUICulture = CultureInfo.InvariantCulture; // uses dot as decimal separator
+            using var _ = new CultureScope(
+                culture: CultureInfo.GetCultureInfo("de-AT"), // uses comma as decimal separator
+                uiCulture: CultureInfo.InvariantCulture); // uses dot as decimal separator
             Length length = Length.FromMeters(1.5);
             string expectedResult = length.ToString(CultureInfo.CurrentCulture);
 

UnitsNet.Tests/UnitAbbreviationsCacheTests.cs

@@ -217,7 +217,6 @@ public void GetDefaultAbbreviationFallsBackToUsEnglishCulture()
             // CurrentCulture also affects localization of unit abbreviations.
             // Zulu (South Africa)
             var zuluCulture = CultureInfo.GetCultureInfo("zu-ZA");
-            // CultureInfo.CurrentCulture = zuluCulture;
 
             var abbreviationsCache = new UnitAbbreviationsCache();
             abbreviationsCache.MapUnitToAbbreviation(CustomUnit.Unit1, AmericanCulture, "US english abbreviation for Unit1");