google.golang.org/genproto/googleapis/rpc v0.0.0-20260831171406-18b4a7587f8a: errdetails.BadRequest

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 in pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260831171406-18b4a7587f8a
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260831171406-18b4a7587f8a
Demonstrate these symbols/APIs:
  - google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest

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:cd4d7506830e755dfff71cb5dff798489342d9b944c5f203f65be1f381703d96","contract":["errdetails.BadRequest.GetFieldViolations returns nil for a nil or uninitialized BadRequest, and returns the configured slice of field violations when set.","errdetails.BadRequest_FieldViolation stores field path and description strings accessible via GetField and GetDescription.","errdetails.BadRequest serializes and deserializes accurately using proto.Marshal and proto.Unmarshal preserving field violations.","errdetails.BadRequest.Reset clears all field violations from the message."],"goal":"verify google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest in pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260831171406-18b4a7587f8a","kind":"HOW","packages":["pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260831171406-18b4a7587f8a"],"schemaVersion":1,"symbols":["google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest"]},"contractCommand":["go","test","./..."],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","executionContext":"go","language":"go","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","runtime":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260831171406-18b4a7587f8a"],"schemaVersion":1,"subject":"pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260831171406-18b4a7587f8a","symbols":["google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest"],"verifierAdapter":"golang@1"}

module example.com/badrequest

go 1.25.0

require (
	google.golang.org/genproto/googleapis/rpc v0.0.0-20260831171406-18b4a7587f8a
	google.golang.org/protobuf v1.36.12
)

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 v0.0.0-20260831171406-18b4a7587f8a h1:3Dnd1cDaZlB68lziofO+bJXpjOy8UfRv8Unt+yH8tQ4=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260831171406-18b4a7587f8a/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"
	"google.golang.org/protobuf/proto"
)

func main() {
	badReq := &errdetails.BadRequest{
		FieldViolations: []*errdetails.BadRequest_FieldViolation{
			{
				Field:       "user.email",
				Description: "must be a valid email address",
			},
			{
				Field:       "user.age",
				Description: "must be greater than or equal to 0",
			},
		},
	}

	for _, v := range badReq.GetFieldViolations() {
		fmt.Printf("Field violation: %s - %s\n", v.GetField(), v.GetDescription())
	}

	data, err := proto.Marshal(badReq)
	if err != nil {
		panic(err)
	}

	var decoded errdetails.BadRequest
	if err := proto.Unmarshal(data, &decoded); err != nil {
		panic(err)
	}
	fmt.Printf("Decoded violations count: %d\n", len(decoded.GetFieldViolations()))

	badReq.Reset()
	fmt.Printf("After reset count: %d\n", len(badReq.GetFieldViolations()))
}

{
  "schemaVersion": 1,
  "goal": "verify google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest in pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260831171406-18b4a7587f8a",
  "kind": "HOW",
  "packages": [
    "pkg:golang/google.golang.org/genproto/googleapis/rpc@v0.0.0-20260831171406-18b4a7587f8a"
  ],
  "symbols": [
    "google.golang.org/genproto/googleapis/rpc/errdetails.BadRequest"
  ]
}

package test

import (
	"testing"

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

func TestBadRequestGetFieldViolations(t *testing.T) {
	// Nil BadRequest returns nil
	var nilBadRequest *errdetails.BadRequest
	if got := nilBadRequest.GetFieldViolations(); got != nil {
		t.Errorf("nilBadRequest.GetFieldViolations() = %v, want nil", got)
	}

	// Empty BadRequest returns nil
	emptyBadRequest := &errdetails.BadRequest{}
	if got := emptyBadRequest.GetFieldViolations(); got != nil {
		t.Errorf("emptyBadRequest.GetFieldViolations() = %v, want nil", got)
	}

	// Populated BadRequest
	v1 := &errdetails.BadRequest_FieldViolation{
		Field:       "user.email",
		Description: "invalid email format",
	}
	v2 := &errdetails.BadRequest_FieldViolation{
		Field:       "user.age",
		Description: "must be at least 18",
	}
	badReq := &errdetails.BadRequest{
		FieldViolations: []*errdetails.BadRequest_FieldViolation{v1, v2},
	}

	violations := badReq.GetFieldViolations()
	if len(violations) != 2 {
		t.Fatalf("expected 2 field violations, got %d", len(violations))
	}
	if violations[0].GetField() != "user.email" || violations[0].GetDescription() != "invalid email format" {
		t.Errorf("violation[0] mismatch: got %v, %v", violations[0].GetField(), violations[0].GetDescription())
	}
	if violations[1].GetField() != "user.age" || violations[1].GetDescription() != "must be at least 18" {
		t.Errorf("violation[1] mismatch: got %v, %v", violations[1].GetField(), violations[1].GetDescription())
	}
}

func TestBadRequestFieldViolationGetters(t *testing.T) {
	var nilViolation *errdetails.BadRequest_FieldViolation
	if got := nilViolation.GetField(); got != "" {
		t.Errorf("nilViolation.GetField() = %q, want empty string", got)
	}
	if got := nilViolation.GetDescription(); got != "" {
		t.Errorf("nilViolation.GetDescription() = %q, want empty string", got)
	}

	v := &errdetails.BadRequest_FieldViolation{
		Field:       "order.quantity",
		Description: "quantity must be positive",
	}
	if v.GetField() != "order.quantity" {
		t.Errorf("v.GetField() = %q, want %q", v.GetField(), "order.quantity")
	}
	if v.GetDescription() != "quantity must be positive" {
		t.Errorf("v.GetDescription() = %q, want %q", v.GetDescription(), "quantity must be positive")
	}
}

func TestBadRequestProtoSerialization(t *testing.T) {
	original := &errdetails.BadRequest{
		FieldViolations: []*errdetails.BadRequest_FieldViolation{
			{
				Field:       "item.id",
				Description: "item id cannot be empty",
			},
		},
	}

	data, err := proto.Marshal(original)
	if err != nil {
		t.Fatalf("proto.Marshal failed: %v", err)
	}

	var unmarshaled errdetails.BadRequest
	if err := proto.Unmarshal(data, &unmarshaled); err != nil {
		t.Fatalf("proto.Unmarshal failed: %v", err)
	}

	if len(unmarshaled.GetFieldViolations()) != 1 {
		t.Fatalf("unmarshaled violations count = %d, want 1", len(unmarshaled.GetFieldViolations()))
	}
	gotV := unmarshaled.GetFieldViolations()[0]
	if gotV.GetField() != "item.id" || gotV.GetDescription() != "item id cannot be empty" {
		t.Errorf("unmarshaled violation mismatch: got field=%q, desc=%q", gotV.GetField(), gotV.GetDescription())
	}
}

func TestBadRequestReset(t *testing.T) {
	badReq := &errdetails.BadRequest{
		FieldViolations: []*errdetails.BadRequest_FieldViolation{
			{
				Field:       "name",
				Description: "required",
			},
		},
	}
	badReq.Reset()
	if got := badReq.GetFieldViolations(); got != nil {
		t.Errorf("badReq.GetFieldViolations() after Reset() = %v, want nil", got)
	}
}