golang.org/x/mod v0.24.0: modfile.Require

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 golang.org/x/mod/modfile.Require in pkg:golang/golang.org/x/mod@v0.24.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/mod@v0.24.0
Demonstrate these symbols/APIs:
  - golang.org/x/mod/modfile.Require

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:c8e6057b9e656d7a5094dc8c95237badc101ddf9c6a5a67e5187eba66c7333f0","contract":["modfile.Require parses direct and indirect dependencies with correct module path, version, and indirect flag","modfile.File.AddNewRequire adds a Require entry with the specified path, version, and indirect status","modfile.File.DropRequire removes the matching Require entry by module path","modfile.File.SetRequire replaces all Require entries and formats consistently on round-trip parsing"],"goal":"verify golang.org/x/mod/modfile.Require in pkg:golang/golang.org/x/mod@v0.24.0","kind":"HOW","packages":["pkg:golang/golang.org/x/mod@v0.24.0"],"schemaVersion":1,"symbols":["golang.org/x/mod/modfile.Require"]},"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/golang.org/x/mod@v0.24.0"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/mod@v0.24.0","symbols":["golang.org/x/mod/modfile.Require"],"verifierAdapter":"golang@1"}

module sample

go 1.23.0

require golang.org/x/mod v0.24.0

golang.org/x/mod v0.24.0 h1:ZfthKaKaT4NrhGVZHO1/WDTwGES4De8KtWO0SIbNJMU=
golang.org/x/mod v0.24.0/go.mod h1:IXM97Txy2VM4PJ3gI61r1YEk/gAj6zAHN3AdZt6S9Ww=

package main

import (
	"fmt"
	"log"

	"golang.org/x/mod/modfile"
)

// ParseRequires parses a go.mod file content and returns its Require statements.
func ParseRequires(filename string, content []byte) ([]*modfile.Require, error) {
	file, err := modfile.Parse(filename, content, nil)
	if err != nil {
		return nil, err
	}
	return file.Require, nil
}

// AddDependency adds a new direct or indirect Require dependency to a go.mod file.
func AddDependency(file *modfile.File, path, version string, indirect bool) {
	file.AddNewRequire(path, version, indirect)
}

func main() {
	content := []byte(`module example.com/app

go 1.23.0

require (
	github.com/google/uuid v1.6.0
	golang.org/x/crypto v0.35.0 // indirect
)
`)

	file, err := modfile.Parse("go.mod", content, nil)
	if err != nil {
		log.Fatalf("Parse failed: %v", err)
	}

	fmt.Printf("Parsed %d requirements:\n", len(file.Require))
	for _, req := range file.Require {
		fmt.Printf(" - %s %s (indirect: %t)\n", req.Mod.Path, req.Mod.Version, req.Indirect)
	}

	AddDependency(file, "golang.org/x/sync", "v0.11.0", false)
	fmt.Printf("Updated requirements count: %d\n", len(file.Require))
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/mod/modfile.Require in pkg:golang/golang.org/x/mod@v0.24.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/mod@v0.24.0"
  ],
  "symbols": [
    "golang.org/x/mod/modfile.Require"
  ]
}

package main

import (
	"fmt"
	"os"

	"golang.org/x/mod/modfile"
	"golang.org/x/mod/module"
)

func main() {
	// 1. modfile.Require parses direct and indirect dependencies with correct module path, version, and indirect flag
	{
		content := []byte(`module example.com/testmod

go 1.23.0

require (
	github.com/google/uuid v1.6.0
	golang.org/x/crypto v0.35.0 // indirect
)
`)

		file, err := modfile.Parse("go.mod", content, nil)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: unexpected parse error: %v\n", err)
			os.Exit(1)
		}

		if len(file.Require) != 2 {
			fmt.Fprintf(os.Stderr, "FAIL: expected 2 requires, got %d\n", len(file.Require))
			os.Exit(1)
		}

		req0 := file.Require[0]
		if req0.Mod.Path != "github.com/google/uuid" || req0.Mod.Version != "v1.6.0" || req0.Indirect != false {
			fmt.Fprintf(os.Stderr, "FAIL: req0 mismatch: path=%s ver=%s indirect=%t\n", req0.Mod.Path, req0.Mod.Version, req0.Indirect)
			os.Exit(1)
		}

		req1 := file.Require[1]
		if req1.Mod.Path != "golang.org/x/crypto" || req1.Mod.Version != "v0.35.0" || req1.Indirect != true {
			fmt.Fprintf(os.Stderr, "FAIL: req1 mismatch: path=%s ver=%s indirect=%t\n", req1.Mod.Path, req1.Mod.Version, req1.Indirect)
			os.Exit(1)
		}
	}

	// 2. modfile.File.AddNewRequire adds a Require entry with the specified path, version, and indirect status
	{
		content := []byte(`module example.com/testmod

go 1.23.0
`)
		file, err := modfile.Parse("go.mod", content, nil)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: parse error: %v\n", err)
			os.Exit(1)
		}

		file.AddNewRequire("golang.org/x/sync", "v0.11.0", false)
		file.AddNewRequire("golang.org/x/sys", "v0.30.0", true)

		if len(file.Require) != 2 {
			fmt.Fprintf(os.Stderr, "FAIL: expected 2 requires after AddNewRequire, got %d\n", len(file.Require))
			os.Exit(1)
		}

		if file.Require[0].Mod.Path != "golang.org/x/sync" || file.Require[0].Mod.Version != "v0.11.0" || file.Require[0].Indirect != false {
			fmt.Fprintf(os.Stderr, "FAIL: direct require mismatch after AddNewRequire\n")
			os.Exit(1)
		}

		if file.Require[1].Mod.Path != "golang.org/x/sys" || file.Require[1].Mod.Version != "v0.30.0" || file.Require[1].Indirect != true {
			fmt.Fprintf(os.Stderr, "FAIL: indirect require mismatch after AddNewRequire\n")
			os.Exit(1)
		}
	}

	// 3. modfile.File.DropRequire removes the matching Require entry by module path
	{
		content := []byte(`module example.com/testmod

go 1.23.0

require (
	github.com/google/uuid v1.6.0
	golang.org/x/sync v0.11.0
)
`)
		file, err := modfile.Parse("go.mod", content, nil)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: parse error: %v\n", err)
			os.Exit(1)
		}

		err = file.DropRequire("github.com/google/uuid")
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: unexpected DropRequire error: %v\n", err)
			os.Exit(1)
		}

		file.Cleanup()
		if len(file.Require) != 1 {
			fmt.Fprintf(os.Stderr, "FAIL: expected 1 require after drop, got %d\n", len(file.Require))
			os.Exit(1)
		}

		if file.Require[0].Mod.Path != "golang.org/x/sync" {
			fmt.Fprintf(os.Stderr, "FAIL: remaining require mismatch: got %s\n", file.Require[0].Mod.Path)
			os.Exit(1)
		}
	}

	// 4. modfile.File.SetRequire replaces all Require entries and formats consistently on round-trip parsing
	{
		content := []byte(`module example.com/testmod

go 1.23.0
`)
		file, err := modfile.Parse("go.mod", content, nil)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: parse error: %v\n", err)
			os.Exit(1)
		}

		newRequires := []*modfile.Require{
			{
				Mod:      module.Version{Path: "github.com/stretchr/testify", Version: "v1.10.0"},
				Indirect: false,
			},
			{
				Mod:      module.Version{Path: "golang.org/x/net", Version: "v0.35.0"},
				Indirect: true,
			},
		}

		file.SetRequire(newRequires)

		formatted, err := file.Format()
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: format error: %v\n", err)
			os.Exit(1)
		}

		reparsed, err := modfile.Parse("go.mod", formatted, nil)
		if err != nil {
			fmt.Fprintf(os.Stderr, "FAIL: round-trip parse error: %v\n", err)
			os.Exit(1)
		}

		if len(reparsed.Require) != 2 {
			fmt.Fprintf(os.Stderr, "FAIL: expected 2 requires in round-trip, got %d\n", len(reparsed.Require))
			os.Exit(1)
		}

		if reparsed.Require[0].Mod.Path != "github.com/stretchr/testify" || reparsed.Require[0].Indirect != false {
			fmt.Fprintf(os.Stderr, "FAIL: round-trip require[0] mismatch\n")
			os.Exit(1)
		}
		if reparsed.Require[1].Mod.Path != "golang.org/x/net" || reparsed.Require[1].Indirect != true {
			fmt.Fprintf(os.Stderr, "FAIL: round-trip require[1] mismatch\n")
			os.Exit(1)
		}
	}

	fmt.Println("PASS: all contract assertions passed")
}