golang.org/x/net v0.47.0: html.EscapeString

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/html.EscapeString in pkg:golang/golang.org/x/net@v0.47.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/net@v0.47.0
Demonstrate these symbols/APIs:
  - golang.org/x/net/html.EscapeString

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:sha256:6d47b3d29c69f988ef8243026e488e9f4359ee684068564aa4e3ed381753d8e4","contract":["html.EscapeString correctly escapes HTML special characters including angle brackets, ampersands, and single and double quotes"],"goal":"verify golang.org/x/net/html.EscapeString in pkg:golang/golang.org/x/net@v0.47.0","kind":"HOW","packages":["pkg:golang/golang.org/x/net@v0.47.0"],"schemaVersion":1,"symbols":["golang.org/x/net/html.EscapeString"]},"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@v0.47.0"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/net@v0.47.0","symbols":["golang.org/x/net/html.EscapeString"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.24.0

require golang.org/x/net v0.47.0

golang.org/x/net v0.47.0 h1:Mx+4dIFzqraBXUugkia1OOvlD6LemFo1ALMHjrXDOhY=
golang.org/x/net v0.47.0/go.mod h1:/jNxtkgq5yWUGYkaZGqo27cfGZ1c5Nen03aYrrKpVRU=

package main

import (
	"fmt"

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

func main() {
	raw := `<div class="content">"Hello & Welcome" <'test'></div>`
	escaped := html.EscapeString(raw)
	fmt.Printf("Original: %s\n", raw)
	fmt.Printf("Escaped:  %s\n", escaped)
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/net/html.EscapeString in pkg:golang/golang.org/x/net@v0.47.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/net@v0.47.0"
  ],
  "symbols": [
    "golang.org/x/net/html.EscapeString"
  ]
}

package main

import (
	"fmt"
	"os"

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

func main() {
	// Assertion: html.EscapeString correctly escapes HTML special characters including angle brackets, ampersands, and single and double quotes
	raw := `<script>alert("Hello & Goodbye 'test'");</script>`
	expected := `&lt;script&gt;alert(&#34;Hello &amp; Goodbye &#39;test&#39;&#34;);&lt;/script&gt;`
	escaped := html.EscapeString(raw)

	if escaped != expected {
		fmt.Fprintf(os.Stderr, "html.EscapeString failed: expected %q, got %q\n", expected, escaped)
		os.Exit(1)
	}

	tests := []struct {
		input    string
		expected string
	}{
		{"", ""},
		{"plain text", "plain text"},
		{"<", "&lt;"},
		{">", "&gt;"},
		{"&", "&amp;"},
		{`"`, "&#34;"},
		{"'", "&#39;"},
		{"<b>&\"'</b>", "&lt;b&gt;&amp;&#34;&#39;&lt;/b&gt;"},
	}

	for _, tc := range tests {
		got := html.EscapeString(tc.input)
		if got != tc.expected {
			fmt.Fprintf(os.Stderr, "html.EscapeString(%q) = %q; expected %q\n", tc.input, got, tc.expected)
			os.Exit(1)
		}
	}

	fmt.Println("All contract assertions passed.")
}