Asserts

GdUnit3 is providing a set of assertions where give you helpful error messages and improves yor test code readability. Assertions are type organized and supports fluent syntax writing.
The pattern for using asserts is defined as assert_<type>(<current>).<comparison function>([expected]).
If you don’t know the type of the current value, use the generic assert_that(<current>) instead.

• GdScript
• C#

• Asserts are restricted by GdScript behavior and therefore do not fully support generics, i.e. you should prefer to use assert by type.
  That is, you must use assert_str for string, for example.

  class_name GdUnitExampleTest
  extends GdUnitTestSuite
  
  func test_hello_world() -> void:
      # using type save assert
      assert_str("Hello world").is_equal("Hello world")
      # using the common assert
      assert_that("Hello world").is_equal("Hello world")
  

• The C# assert are smart and switch to the equivalent assert implementation by auto-typing and should also be used preferentially.
  Alternatively, you can use the typed asserts if you want to
  To use the assert you have to import it via “static GdUnit3.Assertions”.

  using GdUnit3;
  using static GdUnit3.Assertions;
  
  namespace ExampleProject.Tests
  {
      [TestSuite]
      public class ExampleTest
      {
          [TestCase]
          public void HelloWorld()
          {
              AssertThat("Hello world").IsEqual("Hello world");
              // using explicit the typed version
              AssertString("Hello world").IsEqual("Hello world");
          }
      }
  }
  

Advice

You should use the fluent syntax to keep your tests clearer

• GdScript
• C#

• class_name GdUnitExampleTest
  extends GdUnitTestSuite
  
  # A bad example for the multiple use of `assert_str`.
  func test_hello_world() -> void:
      var current := "Hello World"
      assert_str(current).is_equal("Hello World")
      assert_str(current).contains("World")
      assert_str(current).not_contains("Green")
  
  # A good example of using fluent syntax to write more readable tests
  func test_hello_world_fluent() -> void:
      assert_str("Hello World")\
      	.is_equal("Hello World")\
      	.contains("World")\
      	.not_contains("Green")
  

• using GdUnit3;
  using static GdUnit3.Assertions;
  
  namespace ExampleProject.Tests
  {
      [TestSuite]
      public class ExampleTest
      {
          // A bad example for the multiple use of `AssertThat`.
          [TestCase]
          public void HelloWorld()
          {
              string current = "Hello World";
              AssertThat(current).IsEqual("Hello World");
              AssertThat(current).Contains("World");
              AssertThat(current).NotContains("Green");
          }
  
          // A good example of using fluent syntax to write more readable tests
          [TestCase]
          public void HelloWorldFluent()
          {
              AssertThat("Hello World")
                  .IsEqual("Hello World")
                  .Contains("World")
                  .NotContains("Green");
          }
      }
  }    
  

The Generic Assert

• GdScript
• C#

• Can be used for all types and gives you access to the basic test functions of GdUnit Assert.
  However, I recommend to always use the type-safe Assert, because GdScript is not type-safe.

  Assert	Type
  assert_that	auto typing

• The C# assert are smart and switch to the equivalent assert implementation by auto-typing and should also be used preferentially.
  

  Assert	Type
  AssertThat	auto typing

The Basic Build-In Type Asserts

• GdScript
• C#

• Assert	Type
  assert_str	string
  assert_bool	bool
  assert_int	int
  assert_float	float

• Assert	Type
  IStringAssert	string
  IBoolAssert	bool
  INumberAssert	number (sbyte,byte,short,ushort,int,uint,long,ulong,float,double,decimal)

For more details about Build-In types click here Godot Build-In Types

Container Built-In Type Asserts

• GdScript
• C#

• Assert	Type
  assert_array	Array, PoolByteArray, PoolIntArray, PoolRealArray, PoolStringArray, PoolVector2Array, PoolVector3Array, PoolColorArray
  assert_dict	Dictionary

• Assert	Type
  IEnumerableAssert	IEnumerable
  IDictionaryAssert	IDictionary

For more details about Build-In types click here Container built-in types

Engine Build-In Type Asserts

• GdScript
• C#

• Type	Assert
  assert_object	Object
  assert_vector2	Vector2
  assert_vector3	Vector3
  assert_file	File

• Type	Assert
  IObjectAssert	Godot.Object, System.object
  IVector2Assert	Godot.Vector2
  IVector3Assert	Godot.Vector3

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