Add DiscardElements helper transformer

In some situations users want to compare two maps where missing entries
are equal to those that have the zero value.
For example, the following maps would be considered equal:
	x := map[string]int{"foo": 12345, "zero":0}
	y := map[string]int{"foo": 12345}

To help with this, we add DiscardElements to cmpopts that transforms maps
and slices by stripping entries based on a user provided function.
To strip zero values, the user can provide:
	cmpopts.DiscardElements(func(v int) bool { return v == 0 })
4 files changed
tree: 58554278da3eeec38848fcdec7dbb1f99553e7e9
  1. cmp/
  2. .travis.yml
  3. CONTRIBUTING.md
  4. LICENSE
  5. README.md
README.md

Package for equality of Go values

GoDoc Build Status

This package is intended to be a more powerful and safer alternative to reflect.DeepEqual for comparing whether two values are semantically equal.

The primary features of cmp are:

  • When the default behavior of equality does not suit the needs of the test, custom equality functions can override the equality operation. For example, an equality function may report floats as equal so long as they are within some tolerance of each other.

  • Types that have an Equal method may use that method to determine equality. This allows package authors to determine the equality operation for the types that they define.

  • If no custom equality functions are used and no Equal method is defined, equality is determined by recursively comparing the primitive kinds on both values, much like reflect.DeepEqual. Unlike reflect.DeepEqual, unexported fields are not compared by default; they result in panics unless suppressed by using an Ignore option (see cmpopts.IgnoreUnexported) or explictly compared using the AllowUnexported option.

See the GoDoc documentation for more information.

This is not an official Google product.

Install

go get -u github.com/google/go-cmp/cmp

License

BSD - See LICENSE file