golang.org/x/net v0.0.0-20191119073136-fc4aabc6c914: html.ErrBufferExceeded

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.ErrBufferExceeded in pkg:golang/golang.org/x/net@v0.0.0-20191119073136-fc4aabc6c914
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/net@v0.0.0-20191119073136-fc4aabc6c914
Demonstrate these symbols/APIs:
  - golang.org/x/net/html.ErrBufferExceeded

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:sha256:56382931c34810bc169a09771e3233cb0037aec085a3d9005731c2c903abb364","contract":["html.ErrBufferExceeded is a non-nil error with message \"max buffer exceeded\"","Tokenizer.Err() returns html.ErrBufferExceeded when a token exceeds the limit set by Tokenizer.SetMaxBuf","Tokenizer.Err() returns io.EOF when tokens fit within the limit set by Tokenizer.SetMaxBuf"],"goal":"verify golang.org/x/net/html.ErrBufferExceeded in pkg:golang/golang.org/x/net@v0.0.0-20191119073136-fc4aabc6c914","kind":"HOW","packages":["pkg:golang/golang.org/x/net@v0.0.0-20191119073136-fc4aabc6c914"],"schemaVersion":1,"symbols":["golang.org/x/net/html.ErrBufferExceeded"]},"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@v0.0.0-20191119073136-fc4aabc6c914"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/net@v0.0.0-20191119073136-fc4aabc6c914","symbols":["golang.org/x/net/html.ErrBufferExceeded"],"verifierAdapter":"golang@1"}

module sample

go 1.21

require golang.org/x/net v0.0.0-20191119073136-fc4aabc6c914

golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
golang.org/x/net v0.0.0-20191119073136-fc4aabc6c914 h1:MlY3mEfbnWGmUi4rtHOtNnnnN4UJRGSyLPx+DXA5Sq4=
golang.org/x/net v0.0.0-20191119073136-fc4aabc6c914/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

package sample

import (
	"errors"
	"strings"

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

// TokenizeWithLimit tokenizes the provided HTML input using a maximum buffer size limit.
// It returns true if html.ErrBufferExceeded was encountered, along with the terminal error.
func TokenizeWithLimit(input string, maxBuf int) (bool, error) {
	z := html.NewTokenizer(strings.NewReader(input))
	z.SetMaxBuf(maxBuf)
	for {
		tt := z.Next()
		if tt == html.ErrorToken {
			err := z.Err()
			return errors.Is(err, html.ErrBufferExceeded), err
		}
	}
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/net/html.ErrBufferExceeded in pkg:golang/golang.org/x/net@v0.0.0-20191119073136-fc4aabc6c914",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/net@v0.0.0-20191119073136-fc4aabc6c914"
  ],
  "symbols": [
    "golang.org/x/net/html.ErrBufferExceeded"
  ]
}

package main

import (
	"errors"
	"fmt"
	"io"
	"os"

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

func main() {
	if html.ErrBufferExceeded == nil {
		fmt.Fprintln(os.Stderr, "expected html.ErrBufferExceeded to be non-nil")
		os.Exit(1)
	}
	if html.ErrBufferExceeded.Error() != "max buffer exceeded" {
		fmt.Fprintf(os.Stderr, "unexpected ErrBufferExceeded message: %q\n", html.ErrBufferExceeded.Error())
		os.Exit(1)
	}

	exceeded, err := sample.TokenizeWithLimit("<div><span>long content exceeding small buffer</span></div>", 8)
	if !exceeded || !errors.Is(err, html.ErrBufferExceeded) {
		fmt.Fprintf(os.Stderr, "expected ErrBufferExceeded, got exceeded=%v err=%v\n", exceeded, err)
		os.Exit(1)
	}

	exceeded, err = sample.TokenizeWithLimit("<p>ok</p>", 1024)
	if exceeded || !errors.Is(err, io.EOF) {
		fmt.Fprintf(os.Stderr, "expected io.EOF without buffer exceeded, got exceeded=%v err=%v\n", exceeded, err)
		os.Exit(1)
	}
}