golang.org/x/text v0.3.4: cases.NoLower

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/text/cases.NoLower in pkg:golang/golang.org/x/text@v0.3.4
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/text@v0.3.4
Demonstrate these symbols/APIs:
  - golang.org/x/text/cases.NoLower

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:sha256:4d451e51aaf262c565e0604b180012f0b9cd0d87dc631a4f62491de79d6f9631","contract":["Title caser with NoLower preserves interior uppercase letters","Default Title caser without NoLower lowercases interior uppercase letters","Title caser with NoLower keeps all-uppercase words intact","Title caser with NoLower uppercases leading lowercase letters of words","Title caser with NoLower transforms byte slices via Bytes","Title caser with NoLower honors language-specific titlecase rules (Dutch IJ)","Title caser with NoLower returns empty string for empty input"],"goal":"verify golang.org/x/text/cases.NoLower in pkg:golang/golang.org/x/text@v0.3.4","kind":"HOW","packages":["pkg:golang/golang.org/x/text@v0.3.4"],"schemaVersion":1,"symbols":["golang.org/x/text/cases.NoLower"]},"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/text@v0.3.4"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/text@v0.3.4","symbols":["golang.org/x/text/cases.NoLower"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.26.6

require golang.org/x/text v0.3.4

golang.org/x/text v0.3.4 h1:0YWbFKbhXG/wIiuHDSKpS0Iy7FSA+u45VtBMfQcFTTc=
golang.org/x/text v0.3.4/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=

package main

import (
	"fmt"

	"golang.org/x/text/cases"
	"golang.org/x/text/language"
)

func main() {
	caser := cases.Title(language.English, cases.NoLower)
	fmt.Println(caser.String("macOS and iOS devices"))
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/text/cases.NoLower in pkg:golang/golang.org/x/text@v0.3.4",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/text@v0.3.4"
  ],
  "symbols": [
    "golang.org/x/text/cases.NoLower"
  ]
}

package main

import (
	"bytes"
	"fmt"
	"os"

	"golang.org/x/text/cases"
	"golang.org/x/text/language"
)

func main() {
	// 1. Title caser with NoLower preserves interior uppercase letters
	caserNoLower := cases.Title(language.English, cases.NoLower)
	if got := caserNoLower.String("macOS and iOS"); got != "MacOS And IOS" {
		fmt.Fprintf(os.Stderr, "assertion 1 failed: got %q\n", got)
		os.Exit(1)
	}

	// 2. Default Title caser without NoLower lowercases interior uppercase letters
	caserDefault := cases.Title(language.English)
	if got := caserDefault.String("macOS and iOS"); got != "Macos And Ios" {
		fmt.Fprintf(os.Stderr, "assertion 2 failed: got %q\n", got)
		os.Exit(1)
	}

	// 3. Title caser with NoLower keeps all-uppercase words intact
	if got := caserNoLower.String("HTTP and JSON API"); got != "HTTP And JSON API" {
		fmt.Fprintf(os.Stderr, "assertion 3 failed: got %q\n", got)
		os.Exit(1)
	}

	// 4. Title caser with NoLower uppercases leading lowercase letters of words
	if got := caserNoLower.String("simple title test"); got != "Simple Title Test" {
		fmt.Fprintf(os.Stderr, "assertion 4 failed: got %q\n", got)
		os.Exit(1)
	}

	// 5. Title caser with NoLower transforms byte slices via Bytes
	if got := caserNoLower.Bytes([]byte("eBay store")); !bytes.Equal(got, []byte("EBay Store")) {
		fmt.Fprintf(os.Stderr, "assertion 5 failed: got %q\n", string(got))
		os.Exit(1)
	}

	// 6. Title caser with NoLower honors language-specific titlecase rules (Dutch IJ)
	dutchNoLower := cases.Title(language.Dutch, cases.NoLower)
	if got := dutchNoLower.String("ijmuiden and IJssel"); got != "IJmuiden And IJssel" {
		fmt.Fprintf(os.Stderr, "assertion 6 failed: got %q\n", got)
		os.Exit(1)
	}

	// 7. Title caser with NoLower returns empty string for empty input
	if got := caserNoLower.String(""); got != "" {
		fmt.Fprintf(os.Stderr, "assertion 7 failed: got %q\n", got)
		os.Exit(1)
	}

	fmt.Println("contract passed")
}