`struct` allows adding two structs with overlapping fields, unlike Bazel

[oprypin]

Example:

print(struct(foo = "bar") + struct(foo = "bar"))

Result in Bazel:

Error: cannot add struct instances with common field 'foo'

Result in starlark-go:

struct(foo = "bar")

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Let me know if it is expected for this struct type from starlarkstruct to roughly match Bazel at all, or if this report is invalid.

As far as I'm aware, there's no reasonable workaround for this: to change this behavior, one would need to entirely replace the struct type with their own copy.

[adonovan]

Sorry for the delay. This is a good question. Structs aren't part of the core Starlark language, so they unfortunately underdocumented both in the Go implementation and in Bazel's Starlark dialect.

@tetromino @brandjon Any thoughts on whether struct should be standardized?