Can't use some imports from protoplugin with Node16 resolution

[paul-sachs]

@bufbuild/protoplugin/ecmascript exposes some helpers like localName that seem to be untyped when using moduleResolution: Node16 and module: Node16 compiler settings:

Trying to compile results in the following error:

../protoplugin/dist/cjs/ecmascript/index.d.ts:6:47 - error TS2307: Cannot find module '@bufbuild/protobuf/dist/cjs/private/names.js' or its corresponding type declarations.

6 export declare const localName: typeof import("@bufbuild/protobuf/dist/cjs/private/names.js").localName, reifyWkt: typeof import("@bufbuild/protobuf/dist/cjs/private/reify-wkt.js").reifyWkt;
                                                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

../protoplugin/dist/cjs/ecmascript/index.d.ts:6:130 - error TS2307: Cannot find module '@bufbuild/protobuf/dist/cjs/private/reify-wkt.js' or its corresponding type declarations.

6 export declare const localName: typeof import("@bufbuild/protobuf/dist/cjs/private/names.js").localName, reifyWkt: typeof import("@bufbuild/protobuf/dist/cjs/private/reify-wkt.js").reifyWkt;
                                                                                                                                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


Found 2 errors in the same file, starting at: ../protoplugin/dist/cjs/ecmascript/index.d.ts:6

See reproduction in PR #585.

[timostamm]

This is an interesting issue. For the ESM exports of @bufbuild/protoplugin, we currently emit a .d.ts file that contains:

export declare const localName: typeof import("@bufbuild/protobuf/dist/cjs/private/names.js").localName

This import cannot be resolved with Node16 module resolution. If we were using Node16 module resolution, we would have gotten a compiler error here:

TS2742: The inferred type of 'localName' cannot be named without a reference to '../../../../node_modules/@bufbuild/protobuf/dist/cjs/private/names.js'. This is likely not portable. A type annotation is necessary.

attw cannot currently catch this kind of issue either, see arethetypeswrong/arethetypeswrong.github.io#45.

We can fix this issue, but we should definitely switch to building ESM with Node16 module resolution to guard against this error class.