google.golang.org/genproto/googleapis/rpc v0.0.0-20260904194346-d0f1323225a4: errdetails.BadRequest_FieldViolation

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest_FieldViolation in pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260904194346-d0f1323225a4
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260904194346-d0f1323225a4
Demonstrate these symbols/APIs:
  - google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest_FieldViolation

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:9129ef31496bb02331317f2c604fee718614f133345a7551a226f51b8bf3ca38","contract":["BadRequest_FieldViolation struct instantiates with Field and Description fields","GetField returns the configured field name","GetDescription returns the violation description","BadRequest message accepts a slice of BadRequest_FieldViolation pointers"],"goal":"verify google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest_FieldViolation in pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260904194346-d0f1323225a4","kind":"HOW","packages":["pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260904194346-d0f1323225a4"],"schemaVersion":1,"symbols":["google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest_FieldViolation"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260904194346-d0f1323225a4"],"schemaVersion":1,"subject":"pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260904194346-d0f1323225a4","symbols":["google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest_FieldViolation"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require google.golang.org/genproto/googleapis/rpc v0.0.0-20260904194346-d0f1323225a4

require google.golang.org/protobuf v1.36.12 // indirect

github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260904194346-d0f1323225a4 h1:5t+ZydAFj5kGVLrgCvLmpmCf9ylGRd64hpEronfRaws=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260904194346-d0f1323225a4/go.mod h1:DjtHYE8FKJLivXcBEjGwndXfIC23G0VpXiXKqG179uA=
google.golang.org/protobuf v1.36.12 h1:pJOKDDOyeXErUroCihFAd5LQuwXBSpVnKGrj5o/fwxc=
google.golang.org/protobuf v1.36.12/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=

package main

import (
	"fmt"

	"google.golang.org/genproto/googleapis/rpc/errdetails"
)

func main() {
	fv := &errdetails.BadRequest_FieldViolation{
		Field:       "username",
		Description: "username must not be empty",
	}

	br := &errdetails.BadRequest{
		FieldViolations: []*errdetails.BadRequest_FieldViolation{fv},
	}

	fmt.Printf("BadRequest with violation: %s: %s\n", br.GetFieldViolations()[0].GetField(), br.GetFieldViolations()[0].GetDescription())
}

{
  "schemaVersion": 1,
  "goal": "verify google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest_FieldViolation in pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260904194346-d0f1323225a4",
  "kind": "HOW",
  "packages": [
    "pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260904194346-d0f1323225a4"
  ],
  "symbols": [
    "google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest_FieldViolation"
  ]
}

package main

import (
	"fmt"
	"os"

	"google.golang.org/genproto/googleapis/rpc/errdetails"
)

func main() {
	fv := &errdetails.BadRequest_FieldViolation{
		Field:       "username",
		Description: "username must not be empty",
	}

	if fv.GetField() != "username" {
		fmt.Fprintf(os.Stderr, "assertion failed: expected field 'username', got '%s'\n", fv.GetField())
		os.Exit(1)
	}

	if fv.GetDescription() != "username must not be empty" {
		fmt.Fprintf(os.Stderr, "assertion failed: expected description 'username must not be empty', got '%s'\n", fv.GetDescription())
		os.Exit(1)
	}

	br := &errdetails.BadRequest{
		FieldViolations: []*errdetails.BadRequest_FieldViolation{fv},
	}

	if len(br.GetFieldViolations()) != 1 {
		fmt.Fprintf(os.Stderr, "assertion failed: expected 1 violation, got %d\n", len(br.GetFieldViolations()))
		os.Exit(1)
	}

	if br.GetFieldViolations()[0].GetField() != "username" {
		fmt.Fprintf(os.Stderr, "assertion failed: expected violation field 'username', got '%s'\n", br.GetFieldViolations()[0].GetField())
		os.Exit(1)
	}

	if br.GetFieldViolations()[0].GetDescription() != "username must not be empty" {
		fmt.Fprintf(os.Stderr, "assertion failed: expected violation description 'username must not be empty', got '%s'\n", br.GetFieldViolations()[0].GetDescription())
		os.Exit(1)
	}
}