Port the code generator to TypeScript

[timostamm]

This switches the code generator from Go to a TypeScript implementation. There are only very minor changes in the generated code, and some API related to reflection.

New features

• createDescriptorSet() provides a nice way to inspect a set of google.protobuf.FileDescriptorProto
• @bufbuild/protoplugin provides an early version of an API to write your own code generator plugins in TypeScript

Breaking changes

• The code generator can no longer be installed via go.
• class TypeRegistry is deprecated. Please use createRegistry() instead.
• class DescriptorRegistry has been replaced by createRegistryFromDescriptors(). The old version is still available as class LegacyDescriptorRegistry
• class DescriptorSet has been replaced by createDescriptorSet(). The old version is still available as class LegacyDescriptorSet.
• The signatures of makeEnum(), setEnumType() and makeEnumType() have changed slightly for improved enum value names.

Changes in generated code

Imported names are now sorted case-insensitively:

- import {StringValue, proto3} from "@bufbuild/protobuf";
+ import {proto3, StringValue} from "@bufbuild/protobuf";

Uint8Array literals drop the trailing comma:

- { no: 75, name: "default_bytes", kind: "scalar", T: 12 /* ScalarType.BYTES */, opt: true, default: new Uint8Array([0x77, 0x6F, 0x72, 0x6C, 0x64, ]) },
+ { no: 75, name: "default_bytes", kind: "scalar", T: 12 /* ScalarType.BYTES */, opt: true, default: new Uint8Array([0x77, 0x6F, 0x72, 0x6C, 0x64 ]) },

Float and double literals do not use the exponential notation anymore:

- { no: 251, name: "default_float", kind: "scalar", T: 2 /* ScalarType.FLOAT */, opt: true, default: 9e+09 },
+ { no: 251, name: "default_float", kind: "scalar", T: 2 /* ScalarType.FLOAT */, opt: true, default: 9000000000 },

Whitespace in comments is treated slightly different in some edge cases:

  /**
-  *
-  *
   * @generated from field: string this_field_has_an_empty_comment = 4;
   */
  thisFieldHasAnEmptyComment = "";

Prefixed enum values are now stripped more consequently:

export enum BufAlphaRegistryV1Alpha1UserState {
  /**
   * @generated from enum value: BUF_ALPHA_REGISTRY_V1_ALPHA1_USER_STATE_UNSPECIFIED = 0;
   */
- BUF_ALPHA_REGISTRY_V1_ALPHA1_USER_STATE_UNSPECIFIED = 0,
+ UNSPECIFIED = 0,

In generated JavaScript, stripped enum value names are now passed explicitly instead of deriving them:

export const Field_Cardinality = proto3.makeEnum(
  "google.protobuf.Field.Cardinality",
  [
-   {no: 0, name: "CARDINALITY_UNKNOWN"},
-   {no: 1, name: "CARDINALITY_OPTIONAL"},
-   {no: 2, name: "CARDINALITY_REQUIRED"},
-   {no: 3, name: "CARDINALITY_REPEATED"},
+   {no: 0, name: "CARDINALITY_UNKNOWN", localName: "UNKNOWN"},
+   {no: 1, name: "CARDINALITY_OPTIONAL", localName: "OPTIONAL"},
+   {no: 2, name: "CARDINALITY_REQUIRED", localName: "REQUIRED"},
+   {no: 3, name: "CARDINALITY_REPEATED", localName: "REPEATED"},
 ],
- {sharedPrefix: "CARDINALITY_"},
);