Class It<P>

This class allows to express wide range of cases in an expression. You can use it with setups or verifies methods.

Example

 const value = 'value';
 const object = new Mock<Function>()
 .setup(instance => instance(1))
 .returns(value)
 .setup(instance => instance(It.Is(param => param > 0 && param < 2))
 .returns(value)
 .setup(instance => instance(It.IsAny())
 .returns(value)
 .object();

 const actual = object(1);

 expect(actual).toBe(value);
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This class could be used not only for args matching, but also for function names, property names and so on.

Example

const object = new Mock<ITestObject>()
// the expression dynamically checks the property name that is being read
.setup(instance => It.Is((expression: GetPropertyExpression) => expression.name === 'property'))
.returns(value)
.object();

const object = new Mock<ITestObject>()
//denis any write operation on the property
.setup(instance => { instance.property = It.IsAny()})
// true - allow, false - deny
.returns(false)
.object();

const object = new Mock<ITestObject>()
.setup(instance => It.Is((expression: NamedMethodExpression) => expression.name === 'methodName' && expression.args[0] === 1))
.returns(value)
.object();

// how to use with verify
mock.verify(instance => instance.method(It.Is(a => a === 2)));
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