github.com/json-iterator/go v1.1.11: ConfigCompatibleWithStandardLibrary

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/github.com/json-iterator/go@v1.1.11
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/json-iterator/go@v1.1.11

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:sha256:411fb0941ce062dc3ed69163d92ad73f8fb514675272fe89de71686f38957c84","contract":["jsoniter.ConfigCompatibleWithStandardLibrary.Marshal serializes structs obeying json tags and omitempty","jsoniter.ConfigCompatibleWithStandardLibrary.Unmarshal deserializes JSON byte slices into target structs accurately","jsoniter.ConfigCompatibleWithStandardLibrary NewDecoder and NewEncoder correctly stream and encode data","jsoniter.ConfigCompatibleWithStandardLibrary.Unmarshal returns an error when encountering malformed JSON","jsoniter.ConfigCompatibleWithStandardLibrary unmarshals arbitrary JSON values into map and interface types"],"goal":"verify pkg:golang/github.com/json-iterator/go@v1.1.11","kind":"HOW","packages":["pkg:golang/github.com/json-iterator/go@v1.1.11"],"schemaVersion":1,"symbols":["github.com/json-iterator/go.ConfigCompatibleWithStandardLibrary"]},"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/github.com/json-iterator/go@v1.1.11"],"schemaVersion":1,"subject":"pkg:golang/github.com/json-iterator/go@v1.1.11","symbols":["github.com/json-iterator/go.ConfigCompatibleWithStandardLibrary"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require github.com/json-iterator/go v1.1.11

require (
	github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421 // indirect
	github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742 // indirect
)

github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
github.com/json-iterator/go v1.1.11 h1:uVUAXhF2To8cbw/3xN3pxj6kk7TYKs98NIrTqPlMWAQ=
github.com/json-iterator/go v1.1.11/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421 h1:ZqeYNhU3OHLH3mGKHDcjJRFFRrJa6eAM5H+CtDdOsPc=
github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742 h1:Esafd1046DLDQ0W1YjYsBW+p8U2u7vzgW2SQVmlNazg=
github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=

package sample

import (
	"io"

	jsoniter "github.com/json-iterator/go"
)

var json = jsoniter.ConfigCompatibleWithStandardLibrary

// User represents a sample data model with JSON tags.
type User struct {
	ID     int      `json:"id"`
	Name   string   `json:"name"`
	Email  string   `json:"email,omitempty"`
	Roles  []string `json:"roles"`
	Active bool     `json:"active"`
}

// MarshalUser serializes a User struct to JSON bytes using ConfigCompatibleWithStandardLibrary.
func MarshalUser(u User) ([]byte, error) {
	return json.Marshal(u)
}

// UnmarshalUser deserializes JSON bytes into a User struct using ConfigCompatibleWithStandardLibrary.
func UnmarshalUser(data []byte) (User, error) {
	var u User
	err := json.Unmarshal(data, &u)
	return u, err
}

// EncodeUsers streams a slice of User structs to the writer using NewEncoder.
func EncodeUsers(w io.Writer, users []User, indent string) error {
	encoder := json.NewEncoder(w)
	if indent != "" {
		encoder.SetIndent("", indent)
	}
	return encoder.Encode(users)
}

// DecodeUsers reads and decodes a slice of User structs from the reader using NewDecoder.
func DecodeUsers(r io.Reader) ([]User, error) {
	decoder := json.NewDecoder(r)
	var users []User
	err := decoder.Decode(&users)
	return users, err
}

// ExtractAny extracts unstructured data or validates raw JSON bytes using ConfigCompatibleWithStandardLibrary.
func ExtractAny(data []byte) (map[string]interface{}, error) {
	var result map[string]interface{}
	err := json.Unmarshal(data, &result)
	return result, err
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:golang/github.com/json-iterator/go@v1.1.11",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/json-iterator/go@v1.1.11"
  ]
}

package main

import (
	"bytes"
	"fmt"
	"os"
	"reflect"
	"strings"

	jsoniter "github.com/json-iterator/go"
	"sample"
)

func main() {
	var json = jsoniter.ConfigCompatibleWithStandardLibrary

	// Contract 1: jsoniter.ConfigCompatibleWithStandardLibrary.Marshal serializes structs obeying json tags and omitempty
	{
		user := sample.User{
			ID:     101,
			Name:   "Alice",
			Email:  "", // omitempty should exclude this field
			Roles:  []string{"admin", "user"},
			Active: true,
		}

		data, err := sample.MarshalUser(user)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 1]: MarshalUser failed: %v\n", err)
			os.Exit(1)
		}

		outStr := string(data)
		if strings.Contains(outStr, `"email"`) {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 1]: omitempty email should not appear in serialized JSON: %s\n", outStr)
			os.Exit(1)
		}
		if !strings.Contains(outStr, `"id":101`) || !strings.Contains(outStr, `"name":"Alice"`) || !strings.Contains(outStr, `"active":true`) {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 1]: serialized JSON missing expected fields: %s\n", outStr)
			os.Exit(1)
		}
	}

	// Contract 2: jsoniter.ConfigCompatibleWithStandardLibrary.Unmarshal deserializes JSON byte slices into target structs accurately
	{
		payload := []byte(`{"id":202,"name":"Bob","email":"bob@example.com","roles":["dev"],"active":false}`)
		user, err := sample.UnmarshalUser(payload)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 2]: UnmarshalUser failed: %v\n", err)
			os.Exit(1)
		}

		if user.ID != 202 || user.Name != "Bob" || user.Email != "bob@example.com" || user.Active != false || len(user.Roles) != 1 || user.Roles[0] != "dev" {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 2]: Unmarshaled user struct fields mismatch: %+v\n", user)
			os.Exit(1)
		}
	}

	// Contract 3: jsoniter.ConfigCompatibleWithStandardLibrary NewDecoder and NewEncoder correctly stream and encode data
	{
		users := []sample.User{
			{ID: 1, Name: "U1", Roles: []string{"r1"}, Active: true},
			{ID: 2, Name: "U2", Roles: []string{"r2"}, Active: false},
		}

		var buf bytes.Buffer
		if err := sample.EncodeUsers(&buf, users, "  "); err != nil {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 3]: EncodeUsers failed: %v\n", err)
			os.Exit(1)
		}

		encodedStr := buf.String()
		if !strings.Contains(encodedStr, "\n") {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 3]: Indented encoding should contain newlines: %s\n", encodedStr)
			os.Exit(1)
		}

		decodedUsers, err := sample.DecodeUsers(bytes.NewReader(buf.Bytes()))
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 3]: DecodeUsers failed: %v\n", err)
			os.Exit(1)
		}

		if !reflect.DeepEqual(users, decodedUsers) {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 3]: Decoded users do not match original: got %+v, want %+v\n", decodedUsers, users)
			os.Exit(1)
		}
	}

	// Contract 4: jsoniter.ConfigCompatibleWithStandardLibrary.Unmarshal returns an error when encountering malformed JSON
	{
		badPayload := []byte(`{"id": "not_an_int", "broken": `)
		_, err := sample.UnmarshalUser(badPayload)
		if err == nil {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 4]: Expected unmarshal error for malformed JSON, got nil\n")
			os.Exit(1)
		}
	}

	// Contract 5: jsoniter.ConfigCompatibleWithStandardLibrary unmarshals arbitrary JSON values into map and interface types
	{
		dynamicPayload := []byte(`{"key": "value", "count": 42, "flag": true}`)
		m, err := sample.ExtractAny(dynamicPayload)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 5]: ExtractAny failed: %v\n", err)
			os.Exit(1)
		}

		if m["key"] != "value" || m["count"] != float64(42) || m["flag"] != true {
			fmt.Fprintf(os.Stderr, "FAIL [Contract 5]: Arbitrary map values mismatch: %+v\n", m)
			os.Exit(1)
		}
	}

	// Direct check on package API to verify direct package reference
	{
		raw, err := json.Marshal([]int{1, 2, 3})
		if err != nil || string(raw) != `[1,2,3]` {
			fmt.Fprintf(os.Stderr, "FAIL: direct json.Marshal mismatch: %s, %v\n", string(raw), err)
			os.Exit(1)
		}
	}

	fmt.Println("PASS: all pkg:golang/github.com/json-iterator/go@v1.1.11 contracts verified successfully")
}