google.golang.org/protobuf v1.36.4

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 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

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:d08049b70572876a2cdd37f95710eccbe69066fce9fc55e39dbe0d5e85b4755f","contract":["structpb.NewStruct constructs a Struct message from a Go map and proto.Marshal/proto.Unmarshal round-trip wire bytes matching proto.Size","proto.Equal compares protobuf messages for deep equality and proto.Clone creates an independent deep copy that does not mutate the original message","protojson.Marshal and protojson.Unmarshal serialize and deserialize well-known types timestamppb.Timestamp (RFC 3339 string) and durationpb.Duration (seconds string)"],"goal":"verify pkg:golang/google.golang.org/protobuf@v1.36.4","kind":"HOW","packages":["pkg:golang/google.golang.org/protobuf@v1.36.4"],"schemaVersion":1},"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","verifierAdapter":"golang@1"}

module example.com/sample

go 1.23.0

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 pkg:golang/google.golang.org/protobuf@v1.36.4",
  "kind": "HOW",
  "packages": [
    "pkg:golang/google.golang.org/protobuf@v1.36.4"
  ]
}

package main

import (
	"fmt"
	"os"
	"time"

	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/proto"
	"google.golang.org/protobuf/types/known/durationpb"
	"google.golang.org/protobuf/types/known/structpb"
	"google.golang.org/protobuf/types/known/timestamppb"
)

func main() {
	// 1. structpb.NewStruct and proto.Marshal / proto.Unmarshal / proto.Size
	origMap := map[string]any{
		"name":   "widget",
		"count":  float64(42),
		"active": true,
		"tags":   []any{"alpha", "beta"},
	}
	st, err := structpb.NewStruct(origMap)
	if err != nil {
		fmt.Fprintf(os.Stderr, "structpb.NewStruct failed: %v\n", err)
		os.Exit(1)
	}

	wireBytes, err := proto.Marshal(st)
	if err != nil {
		fmt.Fprintf(os.Stderr, "proto.Marshal failed: %v\n", err)
		os.Exit(1)
	}
	if len(wireBytes) == 0 || proto.Size(st) != len(wireBytes) {
		fmt.Fprintf(os.Stderr, "proto.Size mismatch: got %d, len %d\n", proto.Size(st), len(wireBytes))
		os.Exit(1)
	}

	decoded := &structpb.Struct{}
	if err := proto.Unmarshal(wireBytes, decoded); err != nil {
		fmt.Fprintf(os.Stderr, "proto.Unmarshal failed: %v\n", err)
		os.Exit(1)
	}

	// 2. proto.Equal and proto.Clone
	if !proto.Equal(st, decoded) {
		fmt.Fprintln(os.Stderr, "proto.Equal returned false for identical messages")
		os.Exit(1)
	}

	cloned := proto.Clone(st).(*structpb.Struct)
	if !proto.Equal(st, cloned) {
		fmt.Fprintln(os.Stderr, "proto.Clone did not produce equal message")
		os.Exit(1)
	}
	cloned.Fields["name"] = structpb.NewStringValue("modified")
	if proto.Equal(st, cloned) {
		fmt.Fprintln(os.Stderr, "mutating clone affected original or proto.Equal failed to detect change")
		os.Exit(1)
	}
	if st.AsMap()["name"] != "widget" {
		fmt.Fprintf(os.Stderr, "original message mutated: %v\n", st.AsMap()["name"])
		os.Exit(1)
	}

	// 3. protojson.Marshal and protojson.Unmarshal with well-known types
	ts := timestamppb.New(time.Date(2025, 1, 15, 12, 30, 0, 0, time.UTC))
	jsonBytes, err := protojson.Marshal(ts)
	if err != nil {
		fmt.Fprintf(os.Stderr, "protojson.Marshal timestamp failed: %v\n", err)
		os.Exit(1)
	}
	if string(jsonBytes) != `"2025-01-15T12:30:00Z"` {
		fmt.Fprintf(os.Stderr, "unexpected timestamp JSON: %s\n", string(jsonBytes))
		os.Exit(1)
	}

	tsOut := &timestamppb.Timestamp{}
	if err := protojson.Unmarshal(jsonBytes, tsOut); err != nil {
		fmt.Fprintf(os.Stderr, "protojson.Unmarshal timestamp failed: %v\n", err)
		os.Exit(1)
	}
	if !proto.Equal(ts, tsOut) {
		fmt.Fprintln(os.Stderr, "timestamp round-trip mismatch")
		os.Exit(1)
	}

	dur := durationpb.New(90 * time.Second)
	durJSON, err := protojson.Marshal(dur)
	if err != nil {
		fmt.Fprintf(os.Stderr, "protojson.Marshal duration failed: %v\n", err)
		os.Exit(1)
	}
	if string(durJSON) != `"90s"` {
		fmt.Fprintf(os.Stderr, "unexpected duration JSON: %s\n", string(durJSON))
		os.Exit(1)
	}
}