Calling a helper function directly should reduce binary bloat slightly.
Change-Id: I6068dc4cd00c8d90d2e6e6d99633b81388bc8781
Reviewed-on: https://go-review.googlesource.com/c/164679
Reviewed-by: Damien Neil <dneil@google.com>
For a file "foo/bar.proto", put the FileDescriptor in "ProtoFile_foo_bar"
rather than "Bar_fileDescriptor".
Avoid name clashes when a package contains "a/foo.proto" and "b/foo.proto".
Don't camelcase the filename: These vars weren't fully camelcased to begin
with, and leaving the filename relatively unchanged is clearer and more
predictable.
Move "ProtoFile" from the end of the var name to the start, so that vars
will sort better in packages with multiple descriptors.
These changes do add a chance of name collision when the input filename
begins with an uppercase letter: Foo.proto becomes "ProtoFile_Foo", which
could be the result of camelcasing "proto_file.foo". The readability
benefits seem worth it.
Change-Id: If27d3a0d7b5bf3535aa1607a8579eb057c74d2dc
Reviewed-on: https://go-review.googlesource.com/c/163199
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Herbie Ong <herbie@google.com>
This CL takes a significantly different approach to generating support
for protobuf reflection. The previous approach involved generating a
large number of Go literals to represent the reflection information.
While that approach was correct, it resulted in too much binary bloat.
The approach taken here initializes the reflection information from
the raw descriptor proto, which is a relatively dense representation
of the protobuf reflection information. In order to keep initialization
cost low, several measures were taken:
* At program init, the bare minimum is parsed in order to initialize
naming information for enums, messages, extensions, and services declared
in the file. This is done because those top-level declarations are often
relevant for registration.
* Only upon first are most of the other data structures for protobuf
reflection actually initialized.
* Instead of using proto.Unmarshal, a hand-written unmarshaler is used.
This allows us to avoid a dependendency on the descriptor proto and also
because the API for the descriptor proto is fundamentally non-performant
since it requires an allocation for every primitive field.
At a high-level, the new implementation lives in internal/fileinit.
Several changes were made to other parts of the repository:
* cmd/protoc-gen-go:
* Stop compressing the raw descriptors. While compression does reduce
the size of the descriptors by approximately 2x, it is a pre-mature
optimization since the descriptors themselves are around 1% of the total
binary bloat that is due to generated protobufs.
* Seeding protobuf reflection from the raw descriptor significantly
simplifies the generator implementation since it is no longer responsible
for constructing a tree of Go literals to represent the same information.
* We remove the generation of the shadow types and instead call
protoimpl.MessageType.MessageOf. Unfortunately, this incurs an allocation
for every call to ProtoReflect since we need to allocate a tuple that wraps
a pointer to the message value, and a pointer to message type.
* internal/impl:
* We add a MessageType.GoType field and make it required that it is
set prior to first use. This is done so that we can avoid calling
MessageType.init except for when it is actually needed. The allows code
to call (*FooMessage)(nil).ProtoReflect().Type() without fearing that the
init code will run, possibly triggering a recursive deadlock (where the
init code depends on getting the Type of some dependency which may be
declared within the same file).
* internal/cmd/generate-types:
* The code to generate reflect/prototype/protofile_list_gen.go was copied
and altered to generated internal/fileinit.desc_list_gen.go.
At a high-level this CL adds significant technical complexity.
However, this is offset by several possible future changes:
* The prototype package can be drastically simplified. We can probably
reimplement internal/legacy to use internal/fileinit instead, allowing us
to drop another dependency on the prototype package. As a result, we can
probably delete most of the constructor types in that package.
* With the prototype package significantly pruned, and the fact that generated
code no longer depend on depends on that package, we can consider merging
what's left of prototype into protodesc.
Change-Id: I6090f023f2e1b6afaf62bd3ae883566242e30715
Reviewed-on: https://go-review.googlesource.com/c/158539
Reviewed-by: Herbie Ong <herbie@google.com>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
A "_ProtoFile" suffix can potentially conflict with a sub-message named
"ProtoFile" nested within a message that matches the camel-cased
form of the basename of the .proto source file.
Avoid unlikely conflicts and rename this to use a "_protoFile" suffix,
which can never conflict except with an enum value that is also named
"protoFile" (which is a violation of the style guide).
Change-Id: Ie9d22f9f741a63021b8f76906b20c6c2f599885b
Reviewed-on: https://go-review.googlesource.com/c/157218
Reviewed-by: Damien Neil <dneil@google.com>
Most usages of New actually prefer to interact with the reflective view
rather than the native Go type. Thus, change New to return that instead.
This parallels reflect.New, which returns the reflective view
(i.e., reflect.Value) instead of native type (i.e., interface{}).
We make the equivalent change to KnownFields.NewMessage, List.NewMessage,
and Map.NewMessage for consistency.
Since this is a subtle change where the type system will not always
catch the changed type, this change was made by both changing the type
and renaming the function to NewXXX and manually looking at every usage
of the the function to ensure that the usage correctly operates
on either the native Go type or the reflective view of the type.
After the entire codebase was cleaned up, a rename was performed to convert
NewXXX back to New.
Change-Id: I153fef627b4bf0a427e4039ce0aaec52e20c7950
Reviewed-on: https://go-review.googlesource.com/c/157077
Reviewed-by: Damien Neil <dneil@google.com>
Drop the protoreflect.ProtoEnum type (containing a single method
returning a protoreflect.Enum) and make generated enum types
directly implement protoreflect.Enum instead.
Messages have a two-level type split (ProtoMessage and Message) to
minimize conflicts between reflection methods and field names. Enums
need no such split, since enums do not have fields and therefore have
no source of conflicts.
Change-Id: I2b6222e9404253e6bfef2217859e1b760ffcd29b
Reviewed-on: https://go-review.googlesource.com/c/156902
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Damien Neil <dneil@google.com>
Add fields to the Message and Field builder structs which hold the value
of MessageOptions.map_entry, FieldOptions.packed, and FieldOptions.weak
options. Remove all access to the contents of options messages from the
prototype package.
Change IsPacked to always return false for unpackable field types,
which is consistent with the equivalent C++ API.
This change helps avoid dependency cycles between prototype and the
options messages. (Previously this was resolved by accessing options
with reflection, but just breaking the dependency from prototype to the
options message is cleaner and simpler.)
Change-Id: I756aefe2e04cfa8fea31eaaaa0b5a99d4ac9e851
Reviewed-on: https://go-review.googlesource.com/c/153517
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Remove the Mutable methods from KnownFields, List, and Map, replacing
them with methods which return a new, empty message value without adding
that value to the collection.
The new API is simpler, since it clearly applies only to message values,
and more orthogonal, since it provides a way to create a value without
mutating the collection. This latter point is particularly useful in
map deserialization, where the key may be unknown at the time the value
is deserialized.
Drop the Mutable interface, since it is no longer necessary.
Change-Id: Ic5f3d06a2aa331a5d5cd2b4e670a3dba4a74f77c
Reviewed-on: https://go-review.googlesource.com/c/153278
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
The following TODOs were addressed:
* Consistently collect all enums, messages, and extensions in a breadth-first order.
The practical affect of this is that the declaration order in a Go file may change.
This simplifies reflection generation, which relies on consistent ordering.
* Removal of placeholder declarations (e.g., "var _ = proto.Marshal") since
protogen is intelligent about including imports as necessary.
* Always generate a default variable or constant for explicit empty strings.
The practical effect of this is the addition of new declarations in some cases.
However, it simplifies our logic such that it matches the protobuf data model.
* Generate the registration statements in a consistent order.
Change-Id: I627bb72589432bb65d53b50965ea88e5f7983977
Reviewed-on: https://go-review.googlesource.com/c/152778
Reviewed-by: Damien Neil <dneil@google.com>
Implement support in protoc-gen-go for generating messages and enums
that satisfy the v2 protobuf reflection interfaces. Specifically, the following
are added:
* top-level variable representing the file descriptor
* ProtoReflect method on enums (to implement protoV2.Enum)
* ProtoReflect method on messages (to implement protoV2.Message)
The following are not supported yet:
* resolving transitive dependencies for file imports
* Extension descriptors
* Service descriptors
The implementation approach creates a single array for all the message and enum
declarations and references sections of that array to complete dependencies.
Since protobuf declarations can form a graph (a message may depend on itself),
it is difficult to construct a graph as a single literal. One way is to use
placeholder descriptors, but that is not efficient as it requires encoding
the full name of each dependent enum and message and then later resolving it;
thus, both expanding the binary size and also increasing initialization cost.
Instead, we add a prototype.{Enum,Message}.Reference method to obtain a
descriptor reference for the purposes for satisfying dependencies.
As such, nested declarations and dependencies are populated in an init function.
Other changes to support the implementation:
* Added a protoimpl package to expose the MessageType type and also the
MessageTypeOf and EnumTypeOf helper functions.
* Added a protogen.File.GoIdent field to provide a suggested variable name
for the file descriptor.
* Added prototype.{Enum,Message}.Reference that provides a descriptor reference
for the purposes for satisfying cyclic dependencies.
* Added protoreflect.{Syntax,Cardinality,Kind}.GoString to obtain a Go source
identifier that represents the given constant.
Change-Id: I9455764882dee6ad10f251901e7d419091e8bf1d
Reviewed-on: https://go-review.googlesource.com/c/150074
Reviewed-by: Damien Neil <dneil@google.com>
The marshaler, unmarshaler, and sizer functions are unused ever since
the underlying implementation was switched to be table-driven.
Change the function to only return the wrapper structs.
This change:
* enables generated protos to drop dependencies on certain proto types
* reduces the size of generated protos
* simplifies the implementation of oneofs in protoc-gen-go
Updates #708
Change-Id: I845c9009bc0236d1b51d34b014dc3e184303c0f2
Reviewed-on: https://go-review.googlesource.com/c/151357
Reviewed-by: Damien Neil <dneil@google.com>
A .proto source file with no 'package' statement may still contain
references to descriptors within the file.
Change-Id: I86e942c9c06e5a2915e9722162e0455ffa9ba2ab
Reviewed-on: https://go-review.googlesource.com/c/140899
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Enums, for historical reasons, are registered with the proto package
under the name "<proto_package>.<go_type_name>". Don't include the dot
if there is no package statement in the .proto source file.
Change-Id: I6fb57d0803506668f60123a29fa06ae87fec523b
Reviewed-on: https://go-review.googlesource.com/c/140657
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
