golang.org/x/net v0.12.0: publicsuffix.PublicSuffix

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/net/publicsuffix.PublicSuffix in pkg:golang/golang.org/x/net@v0.12.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/net@v0.12.0
Demonstrate these symbols/APIs:
  - golang.org/x/net/publicsuffix.PublicSuffix

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:sha256:2cc2be891c0eb138da1e4c293f65654246f717c5f4e8c011dfd530682871804c","contract":["publicsuffix.PublicSuffix extracts the public suffix and indicates if it is managed by ICANN for domain names"],"goal":"verify golang.org/x/net/publicsuffix.PublicSuffix in pkg:golang/golang.org/x/net@v0.12.0","kind":"HOW","packages":["pkg:golang/golang.org/x/net@v0.12.0"],"schemaVersion":1,"symbols":["golang.org/x/net/publicsuffix.PublicSuffix"]},"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/net@v0.12.0"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/net@v0.12.0","symbols":["golang.org/x/net/publicsuffix.PublicSuffix"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.25.0

require golang.org/x/net v0.12.0

golang.org/x/net v0.12.0 h1:cfawfvKITfUsFCeJIHJrbSxpeu/E81khclypR0GVT50=
golang.org/x/net v0.12.0/go.mod h1:zEVYFnQC7m/vmpQFELhcD1EWkZlX69l4oqgmer6hfKA=

package main

import (
	"fmt"

	"golang.org/x/net/publicsuffix"
)

func main() {
	domains := []string{
		"example.com",
		"subdomain.example.co.uk",
		"golang.org",
		"myproject.github.io",
	}

	for _, domain := range domains {
		suffix, icann := publicsuffix.PublicSuffix(domain)
		fmt.Printf("domain: %s -> suffix: %s, icann: %t\n", domain, suffix, icann)
	}
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/net/publicsuffix.PublicSuffix in pkg:golang/golang.org/x/net@v0.12.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/net@v0.12.0"
  ],
  "symbols": [
    "golang.org/x/net/publicsuffix.PublicSuffix"
  ]
}

package main

import (
	"fmt"
	"os"

	"golang.org/x/net/publicsuffix"
)

func main() {
	// Assertion 1: publicsuffix.PublicSuffix extracts the public suffix and indicates if it is managed by ICANN for domain names
	{
		testCases := []struct {
			domain     string
			wantSuffix string
			wantICANN  bool
		}{
			{"example.com", "com", true},
			{"foo.example.co.uk", "co.uk", true},
			{"golang.org", "org", true},
			{"myproject.github.io", "github.io", false},
			{"customblog.blogspot.com", "blogspot.com", false},
			{"localhost", "localhost", false},
		}

		for _, tc := range testCases {
			gotSuffix, gotICANN := publicsuffix.PublicSuffix(tc.domain)
			if gotSuffix != tc.wantSuffix || gotICANN != tc.wantICANN {
				fmt.Fprintf(os.Stderr, "assertion 1 failed for %q: got (%q, %v), want (%q, %v)\n",
					tc.domain, gotSuffix, gotICANN, tc.wantSuffix, tc.wantICANN)
				os.Exit(1)
			}
		}
	}

	fmt.Println("PASS: pkg:golang/golang.org/x/net@v0.12.0 contract passed")
}