Except where otherwise provided by this chapter, a permanent injunction may be granted to prevent the breach of an obligation existing in favor of the applicant:

1. (1) Where pecuniary compensation would not afford adequate relief;
2. (2) Where it would be extremely difficult to ascertain the amount of compensation which would afford adequate relief;
3. (3) Where the restraint is necessary to prevent a multiplicity of judicial proceedings; or
4. (4) Where the obligation arises from a trust.

Source: CivC 1877, § 2016; CL 1887, § 4649; RCivC 1903, § 2361; RC 1919, § 2034; SDC 1939 & Supp 1960, § 37.4303; SL 1978, ch 155 , § 18.