Enum validation fails when enum is defined in separate thrift file about thrifty

[benjamin-bader]

Just confirmed my reading using the Apache compiler:

a.thrift:

namespace java a

enum Foo {
  One
}

b.thrift:

namespace java b

struct Bar {
  1: required a.Foo foo = One
}

$ thrift -gen java b.thrift
> [FAILURE:/Users/bendb/Development/thrift/b.thrift:6] error: identifier One is unqualified!

I'll have a fix for the initial bug, but don't want to deviate from Apache's behavior more than necessary; we'll match this validation behavior.

[benjamin-bader]

Interesting. My understanding of the IDL spec is that one is required to use the fully-qualified name of imported type; from my perspective, this is working as intended. I would expect the following to work:

1: required testing_foo.Foo foo = testing_foo.Foo.One;

Is this behavior different from that of the Apache compiler?

[yfrancis]

@benjamin-bader the fully qualified name is used for the field type, the Apache compiler accepts multiple forms:

required testing_foo.Foo foo = testing_foo.Foo.One
required testing_foo.Foo foo = Foo.One
required testing_foo.Foo foo = One
required testing_foo.Foo foo = 1

Whats interesting is that thrifty links all of these correctly - the type is resolved to the imported enum, its just the constant validation that fails because it does linker.lookupSymbol("Foo") rather than linker.lookupSymbol("testing_foo.Foo").

From our investigation, the symbol testing_foo.Foo is available at the field level, but when validation is performed on the constant value itself, this information is not passed through.

[benjamin-bader]

Thanks @yfrancis, that's really helpful!

Thrift's inconsistencies are going to be the death of me. I'll have a fix soon.

[benjamin-bader]

OK, I've finally got some time to address this. As I'm looking over the Apache compiler, it certainly appears that unqualified enum references in constants (e.g. required testing_foo.Foo foo = One) are not accepted; this is as of version 0.9.3. What version are you using that allows this?

t_const_value.h is approximately the same things as Thrifty's ConstValueElement, and defines accessors used during const validation. The ones relevant to enums throw exceptions (i.e. fail) during const validation: https://github.com/apache/thrift/blob/0.9.3/compiler/cpp/src/parse/t_const_value.h#L107

How was this working for you previously?