Add a sentinel proto.Error error which matches all errors returned by
packages in this module.
Document that protoregistry.NotFound is an exact sentinel value for
performance reasons.
Add a Wrap function to the internal/errors package and use it to wrap
errors from outside sources (resolvers). Wrapped errors match
proto.Error.
Fixesgolang/protobuf#1021.
Change-Id: I45567df3fd6c8dc9a5caafdb55654827f6fb1941
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/215338
Reviewed-by: Joe Tsai <joetsai@google.com>
Hyrum's Law dictates that if we do not prevent naughty behavior,
people will rely on it. If we do not validate that the provided
file descriptor is correct today, it will be near impossible
to add proper validation checks later on.
The logic added validates that the provided file descriptor is
correct according to the same semantics as protoc,
which was reversed engineered to derive the set of rules implemented here.
The rules are unfortunately complicated because protobuf is a language
full of many non-orthogonal features. While our logic is complicated,
it is still 1/7th the size of the equivalent C++ code!
Change-Id: I6acc5dc3bd2e4c6bea6cd9e81214f8104402602a
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/184837
Reviewed-by: Damien Neil <dneil@google.com>
Overview of changes:
* Add an option that specifies whether to replace unresolvable references
with a placeholder instead of producing an error. Since the prior behavior
produced placeholders (not always), we default to that behavior for now,
but will enable strict resolving in a future CL.
* The option is not yet exported because there is concern about what the
public API should look like. This will be exposed in a future CL.
* Unlike before, we now permit placeholders for unresolvable enum values.
* We implement relative name resolution logic.
* We handle the case where the type is unknown, but type_name is specified.
In such a case, we populate both FieldDescriptor.{Enum,Message} and leave
the FieldDescriptor.Kind with the zero value. If the type_name happened
to resolve, we use that to determine the type.
* If a placeholder is used to represent a relative name,
the FullName reports an invalid full name with a "*." prefix.
Change-Id: Ifa8c750423c488fb9324eec4d033a2f251505fda
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/184317
Reviewed-by: Damien Neil <dneil@google.com>
This fixes a bug introduced by CL/182360.
Overview of the problem:
* CL/182360 removes the internal/prototype package, such that
protodesc was re-implemented using internal/filedesc.
* As a result of that change, resolving internal dependencies became
the responsibility of protodesc.
* Dependency resolution used the following two-pass algorithm:
1) first pass derives the full name of all declarations
2) second pass fully initializes each descriptor declaration,
now being able to resolve local dependencies from the previous step.
* When the second pass looks up a local dependency, it is guaranteed to
find it, but it is not guaranteed that the dependency has been initialized
(since it may appear later on). This is problematic for default enum values
since it implies that the enum dependency may not be sufficiently
initialized to be able to query its set of values, leading to panics.
* CL/182360 recognized the problem and attempted to enforce an initialization
ordering where nested enums were always initialized before the body of the
message declaration itself.
* However, that ordering fails to enforce that that enum declarations outside
the parent tree are initialized beforehand. For example, referring to an
enum value that is declared within a sibling of the parent message.
* This CL fixes the problem with a three-pass algorithm:
1) first pass derives the full name *and* fully initialize the
entire descriptor *except* for dependency references (i.e., type_name).
2) second pass only resolves dependency references,
where we do not need to worry about initialization ordering.
3) third pass validates the descriptors are well-formed.
This can now depend on all information being fully initialized.
* While a lot of code moves, this change is actually very mechanical.
Other than split things apart, no new logic is introduced nor removed.
Change-Id: Ia91d4aade8f6187c19d704d43ae96b3b9d276792
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/184297
Reviewed-by: Damien Neil <dneil@google.com>