MockeryExtras.Getters (Mockery Extras v0.3.1) View Source
Utilities for defining functions that get map/struct/keyword values up to three levels of nesting.
Even though complex nested structures aren't necessarily the best thing for your code, they sometimes exist:
all = %{
top1: 1,
top2: 1.2,
down: %{
lower: 2,
down: %{
lowest: 3
}
}
}You're stuck with them, at least for now. You'd often prefer not to spread knowledge of the exact structure through the code, because that would make a lot of code fragile in the face of change.
So you can hide the structure behind "getters" that (alone) know how to reach into the structure and retrieve a value. They present a "flattened" API to client code.
Those functions are simple to write manually, but you might as well use a macro to do it for you:
getters([:top1, :top2])
# defines top1/1, top2/1, so that:
# top1(all) => 1
# top2(all) => 2
# Three levels of nesting are allowed.
getters(:down, :down, [:lowest])
# lowest(all) => 3See getters/1 for details, such as how to specify default values
(akin to those of Map.get/3 or Keyword.get/3).
See Stubbing Complex
Structures
to see how a little bit of custom (copy and tweak) work can improve
the testing of code that works against a flattened API, plus an
alternative to verbose code like MyStructure.getter(structure).
Link to this section Summary
Functions
Define a single getter with a different name than the field it accesses.
Define N getters, possibly with defaults.
Define N getters for the second level of a nested structure.
Define N getters for the third level of a nested structure.
The same as getters/1 except the functions are generated using defp.
The same as getters/2 except the functions are generated using defp.
The same as getters/3 except the functions are generated using defp.
Link to this section Functions
Define a single getter with a different name than the field it accesses.
For example, this:
getter :meio, for: [:root, :middle]
# meio(root: %{middle: 3}) => 3A default can also be provided:
getter :meio, for: [:root, :middle], default: "default"
# meio(root: %{}) => "default"If the getter is for the top level, the for: value needn't be a list:
getter :raiz, for: :rootDefine N getters, possibly with defaults.
The argument must be a list. For each atom in the list, a function effectively like the following is defined:
def atom(structure), do: structure[atom]Note that the getter's argument can be either a Map or a Keyword.
Default values can be given:
getters([:x, y: "some default"])
# y(%{}) => "some default"If there's no default, a missing value will produce a KeyError.
Define N getters for the second level of a nested structure.
The first argument is an atom that's expected to index
a Map or Keyword. The value of that index is again expected to be
a Map or Keyword.
The second argument is a list with the same form as in
getters/1. It provides the names for the generated functions. (The
first argument plays no role.)
getters(:top, [:x, y: "some default"])
# x(%{top: [x: 1]}) => 1
# y(%{top: [ ]}) => "some default"Note that the default only applies at the bottom level. The
following will raise a RuntimeError:
Define N getters for the third level of a nested structure.
The same as getters/1 except the functions are generated using defp.
Most often this is used in a module that defines a structure, its getters, and also more complicated functions that work on the structure.
The same as getters/2 except the functions are generated using defp.
The same as getters/3 except the functions are generated using defp.