Avoid leaking implementation details of the exporter (#206)

The current implementation for forcibly exporting fields relies on
the reflect.Value.Addr method for the parent struct value,
where it copies a non-addressable struct onto to the heap so
that it is addressable. However, this action leaks a subtle detail
of how the internal implementation works since the accessed field
for within a struct is only addressable if and only if the
parent struct is also addressable.

Modify the implementation to avoid leaking this implementation detail
by shallow copying the accessed unexported field to remove any
notion of addressability if the parent struct is also unaddressable.

Fixes #181
6 files changed
tree: 665edc6d6efa7416baba1daa03dfb819c41da76a
  1. .travis.yml
  4. README.md
  5. cmp/
  6. go.mod
  7. go.sum

Package for equality of Go values

GoDev 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 explicitly compared using the AllowUnexported option.

See the documentation for more information.

This is not an official Google product.


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


BSD - See LICENSE file