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class

test.default.MockPropertyContext

class MockPropertyContext<PropertyType = any>

  • readonly accesses: { stack: Error; type: 'get' | 'set'; value: PropertyType }[]

    A getter that returns a copy of the internal array used to track accesses (get/set) to the mocked property. Each entry in the array is an object with the following properties:

  • accessCount(): number;

    This function returns the number of times that the property was accessed. This function is more efficient than checking ctx.accesses.length because ctx.accesses is a getter that creates a copy of the internal access tracking array.

    @returns

    The number of times that the property was accessed (read or written).

  • value: PropertyType
    ): void;

    This function is used to change the value returned by the mocked property getter.

    @param value

    The new value to be set as the mocked property value.

  • value: PropertyType,
    onAccess?: number
    ): void;

    This function is used to change the behavior of an existing mock for a single invocation. Once invocation onAccess has occurred, the mock will revert to whatever behavior it would have used had mockImplementationOnce() not been called.

    The following example creates a mock function using t.mock.property(), calls the mock property, changes the mock implementation to a different value for the next invocation, and then resumes its previous behavior.

    test('changes a mock behavior once', (t) => {
  const obj = { foo: 1 };

  const prop = t.mock.property(obj, 'foo', 5);

  assert.strictEqual(obj.foo, 5);
  prop.mock.mockImplementationOnce(25);
  assert.strictEqual(obj.foo, 25);
  assert.strictEqual(obj.foo, 5);
});
    @param value

    The value to be used as the mock's implementation for the invocation number specified by onAccess.

    @param onAccess

    The invocation number that will use value. If the specified invocation has already occurred then an exception is thrown. Default: The number of the next invocation.

  • resetAccesses(): void;

    Resets the access history of the mocked property.

  • restore(): void;

    Resets the implementation of the mock property to its original behavior. The mock can still be used after calling this function.