golang.org/x/tools v0.1.1: txtar.Parse

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/tools/txtar.Parse in pkg:golang/golang.org/x/tools@v0.1.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/tools@v0.1.1
Demonstrate these symbols/APIs:
  - golang.org/x/tools/txtar.Parse

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:c0599442aafbbbb322394806327eb3c74b40029a8774d41aa171628220c61a39","contract":["txtar.Parse parses archive byte data into comment and file entries with correct names and contents","txtar.Parse returns an empty comment and empty files slice when given empty input","txtar.Parse parses multiple files including subdirectories and preserves file contents across boundaries"],"goal":"verify golang.org/x/tools/txtar.Parse in pkg:golang/golang.org/x/tools@v0.1.1","kind":"HOW","packages":["pkg:golang/golang.org/x/tools@v0.1.1"],"schemaVersion":1,"symbols":["golang.org/x/tools/txtar.Parse"]},"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/tools@v0.1.1"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/tools@v0.1.1","symbols":["golang.org/x/tools/txtar.Parse"],"verifierAdapter":"golang@1"}

module sample-txtar-parse

go 1.23.0

require golang.org/x/tools v0.1.1

golang.org/x/tools v0.1.1 h1:wGiQel/hW0NnEkJUk8lbzkX2gFJU6PFxf1v5OlCfuOs=
golang.org/x/tools v0.1.1/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=

package main

import (
	"fmt"

	"golang.org/x/tools/txtar"
)

func main() {
	raw := []byte("Archive comment\n-- greeting.txt --\nHello, world!\n-- notes/todo.txt --\nItem 1\nItem 2\n")
	archive := txtar.Parse(raw)

	fmt.Printf("Comment: %s\n", string(archive.Comment))
	for _, f := range archive.Files {
		fmt.Printf("File %s: %s", f.Name, string(f.Data))
	}
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/tools/txtar.Parse in pkg:golang/golang.org/x/tools@v0.1.1",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/tools@v0.1.1"
  ],
  "symbols": [
    "golang.org/x/tools/txtar.Parse"
  ]
}

package main

import (
	"bytes"
	"fmt"
	"os"

	"golang.org/x/tools/txtar"
)

func main() {
	// Assertion 1: txtar.Parse parses archive byte data into comment and file entries with correct names and contents
	{
		input := []byte("Header comment line 1\nHeader comment line 2\n-- hello.txt --\nHello world\n")
		ar := txtar.Parse(input)
		if ar == nil {
			fmt.Fprintln(os.Stderr, "FAIL: txtar.Parse returned nil")
			os.Exit(1)
		}
		expectedComment := "Header comment line 1\nHeader comment line 2\n"
		if string(ar.Comment) != expectedComment {
			fmt.Fprintf(os.Stderr, "FAIL: expected comment %q, got %q\n", expectedComment, string(ar.Comment))
			os.Exit(1)
		}
		if len(ar.Files) != 1 {
			fmt.Fprintf(os.Stderr, "FAIL: expected 1 file, got %d\n", len(ar.Files))
			os.Exit(1)
		}
		if ar.Files[0].Name != "hello.txt" {
			fmt.Fprintf(os.Stderr, "FAIL: expected file name 'hello.txt', got %q\n", ar.Files[0].Name)
			os.Exit(1)
		}
		expectedData := []byte("Hello world\n")
		if !bytes.Equal(ar.Files[0].Data, expectedData) {
			fmt.Fprintf(os.Stderr, "FAIL: expected data %q, got %q\n", string(expectedData), string(ar.Files[0].Data))
			os.Exit(1)
		}
	}

	// Assertion 2: txtar.Parse returns an empty comment and empty files slice when given empty input
	{
		ar := txtar.Parse([]byte(""))
		if ar == nil {
			fmt.Fprintln(os.Stderr, "FAIL: txtar.Parse returned nil for empty input")
			os.Exit(1)
		}
		if len(ar.Comment) != 0 {
			fmt.Fprintf(os.Stderr, "FAIL: expected empty comment, got %q\n", string(ar.Comment))
			os.Exit(1)
		}
		if len(ar.Files) != 0 {
			fmt.Fprintf(os.Stderr, "FAIL: expected empty files slice, got %d files\n", len(ar.Files))
			os.Exit(1)
		}
	}

	// Assertion 3: txtar.Parse parses multiple files including subdirectories and preserves file contents across boundaries
	{
		input := []byte("-- doc/readme.md --\n# Title\nDescription\n-- src/main.go --\npackage main\n-- config.json --\n{\"enabled\": true}\n")
		ar := txtar.Parse(input)
		if ar == nil {
			fmt.Fprintln(os.Stderr, "FAIL: txtar.Parse returned nil")
			os.Exit(1)
		}
		if len(ar.Comment) != 0 {
			fmt.Fprintf(os.Stderr, "FAIL: expected empty comment, got %q\n", string(ar.Comment))
			os.Exit(1)
		}
		if len(ar.Files) != 3 {
			fmt.Fprintf(os.Stderr, "FAIL: expected 3 files, got %d\n", len(ar.Files))
			os.Exit(1)
		}

		expected := []struct {
			name string
			data string
		}{
			{"doc/readme.md", "# Title\nDescription\n"},
			{"src/main.go", "package main\n"},
			{"config.json", "{\"enabled\": true}\n"},
		}

		for i, exp := range expected {
			if ar.Files[i].Name != exp.name {
				fmt.Fprintf(os.Stderr, "FAIL: file[%d] expected name %q, got %q\n", i, exp.name, ar.Files[i].Name)
				os.Exit(1)
			}
			if string(ar.Files[i].Data) != exp.data {
				fmt.Fprintf(os.Stderr, "FAIL: file[%d] expected data %q, got %q\n", i, exp.data, string(ar.Files[i].Data))
				os.Exit(1)
			}
		}
	}

	fmt.Println("PASS: golang.org/x/tools/txtar.Parse contract passed")
}