google.golang.org/protobuf v1.36.4: wrapperspb.StringValue

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/protobuf/types/known/wrapperspb.StringValue in pkg:golang/google.golang.org/protobuf@v1.36.4
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/google.golang.org/protobuf@v1.36.4
Demonstrate these symbols/APIs:
  - google.golang.org/protobuf/types/known/wrapperspb.StringValue

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:sha256:21578456808815329cbc31bed9742ad6beef68a3bc5081e261a890086c6c1b64","contract":["wrapperspb.StringValue{Value: s}.GetValue() returns s","wrapperspb.String(s) constructs *wrapperspb.StringValue with GetValue() == s","nil *wrapperspb.StringValue.GetValue() returns empty string without panicking","proto.Marshal and proto.Unmarshal round-trip *wrapperspb.StringValue preserving Value"],"goal":"verify google.golang.org/protobuf/types/known/wrapperspb.StringValue in pkg:golang/google.golang.org/protobuf@v1.36.4","kind":"HOW","packages":["pkg:golang/google.golang.org/protobuf@v1.36.4"],"schemaVersion":1,"symbols":["google.golang.org/protobuf/types/known/wrapperspb.StringValue"]},"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/protobuf@v1.36.4"],"schemaVersion":1,"subject":"pkg:golang/google.golang.org/protobuf@v1.36.4","symbols":["google.golang.org/protobuf/types/known/wrapperspb.StringValue"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.22

require google.golang.org/protobuf v1.36.4

github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
google.golang.org/protobuf v1.36.4 h1:6A3ZDJHn/eNqc1i+IdefRzy/9PokBTPvcqMySR7NNIM=
google.golang.org/protobuf v1.36.4/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=

{
  "schemaVersion": 1,
  "goal": "verify google.golang.org/protobuf/types/known/wrapperspb.StringValue in pkg:golang/google.golang.org/protobuf@v1.36.4",
  "kind": "HOW",
  "packages": [
    "pkg:golang/google.golang.org/protobuf@v1.36.4"
  ],
  "symbols": [
    "google.golang.org/protobuf/types/known/wrapperspb.StringValue"
  ]
}

package main

import (
	"fmt"
	"os"

	"google.golang.org/protobuf/proto"
	"google.golang.org/protobuf/types/known/wrapperspb"
)

func main() {
	sv := &wrapperspb.StringValue{Value: "hello-protobuf"}
	if sv.GetValue() != "hello-protobuf" {
		fmt.Fprintf(os.Stderr, "expected hello-protobuf, got %q\n", sv.GetValue())
		os.Exit(1)
	}

	viaConstructor := wrapperspb.String("wrapped-value")
	if viaConstructor.GetValue() != "wrapped-value" {
		fmt.Fprintf(os.Stderr, "expected wrapped-value, got %q\n", viaConstructor.GetValue())
		os.Exit(1)
	}

	var nilVal *wrapperspb.StringValue
	if nilVal.GetValue() != "" {
		fmt.Fprintf(os.Stderr, "expected empty string for nil StringValue, got %q\n", nilVal.GetValue())
		os.Exit(1)
	}

	wire, err := proto.Marshal(sv)
	if err != nil {
		fmt.Fprintf(os.Stderr, "marshal failed: %v\n", err)
		os.Exit(1)
	}

	decoded := &wrapperspb.StringValue{}
	if err := proto.Unmarshal(wire, decoded); err != nil {
		fmt.Fprintf(os.Stderr, "unmarshal failed: %v\n", err)
		os.Exit(1)
	}
	if decoded.GetValue() != "hello-protobuf" {
		fmt.Fprintf(os.Stderr, "roundtrip mismatch: got %q\n", decoded.GetValue())
		os.Exit(1)
	}
}