What is the test for determining whether a mandatory duty of a governmental entity is mandatory?

3 "The legislative intent can usually be determined from the statutory language. [Citation.] However, when the specific language does not shed light as to the intent of the legislature, it can be determined from other factors which indicate the intent of the legislature. [Citation.] It is well established that statutes must be given a reasonable construction that conforms to the apparent purpose and intention of the law makers [citations], and the various parts of the statutory enactment must be harmonized by considering the particular clause in the context of the whole statute. [Citations.]" (Nunn v. State of California, supra, 35 Cal.3d at pp. 624-625, 200 Cal.Rptr. 440, 677 P.2d 846; MacDonald v. State of California, supra, 230 Cal.App.3d at p. 327, 281 Cal.Rptr. 317.)

4 For a comprehensive review of the extensive case law developed over the years on the existence of mandatory duties of governmental entities, see MacDonald v. State of California, supra, 230 Cal.App.3d at pages 327-329, 281 Cal.Rptr. 317.)