What is the test for a materially adverse employment action?

Thus, "'"[a] change that is merely contrary to the employee's interests or not to the employee's liking is insufficient."... "'[W]orkplaces are rarely idyllic retreats, and the mere fact that an employee is displeased by an employer's act or omission does not elevate that act or omission to the level of a materially adverse employment action.'... "'" (Malais v. Los Angeles City Fire Dept., supra, 150 Cal.App.4th at p. 357.) A plaintiff claiming she was subjected to an adverse employment action based on discrimination "'must show the employer's... actions had a detrimental and substantial effect on the plaintiffs employment.'" (Id. at p. 358.)