google.golang.org/appengine v1.2.0: GeoPoint.Valid, IsDevAppServer, MultiError.Error

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 pkg:golang/google.golang.org/appengine@v1.2.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/google.golang.org/appengine@v1.2.0

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:sha256:86e4179b885dadf6d35b90db55764f2ff8b017426dc417bfb3d048fac6247277","contract":["appengine.GeoPoint.Valid returns true for coordinates within [-90, 90] latitude and [-180, 180] longitude and false otherwise","appengine.Namespace returns a replacement context for a valid namespace matching ^[0-9A-Za-z._-]{0,100}$ and returns an error for invalid namespace characters","appengine.MultiError.Error formats zero errors as '(0 errors)' and multiple non-nil errors as '\u003cfirst\u003e (and N other errors)'","appengine.IsDevAppServer returns false outside the development App Server"],"goal":"verify pkg:golang/google.golang.org/appengine@v1.2.0","kind":"HOW","packages":["pkg:golang/google.golang.org/appengine@v1.2.0"],"schemaVersion":1,"symbols":["appengine.GeoPoint.Valid","appengine.IsDevAppServer","appengine.MultiError.Error","appengine.Namespace"]},"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/google.golang.org/appengine@v1.2.0"],"schemaVersion":1,"subject":"pkg:golang/google.golang.org/appengine@v1.2.0","symbols":["appengine.GeoPoint.Valid","appengine.IsDevAppServer","appengine.MultiError.Error","appengine.Namespace"],"verifierAdapter":"golang@1"}

module sample

go 1.26.0

require google.golang.org/appengine v1.2.0

require (
	github.com/golang/protobuf v1.2.0 // indirect
	golang.org/x/net v0.0.0-20180724234803-3673e40ba225 // indirect
	golang.org/x/sync v0.24.0 // indirect
)

github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
golang.org/x/net v0.0.0-20180724234803-3673e40ba225 h1:kNX+jCowfMYzvlSvJu5pQWEmyWFrBXJ3PBy10xKMXK8=
golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
golang.org/x/sync v0.24.0 h1:iqiDrGoDgyuvAKrhLQthUEzU/R378N78gXbBjxed7oA=
golang.org/x/sync v0.24.0/go.mod h1:sUUOizhqBxiL6pEWpqNLUiaJn1ShEbZ6BBqskPbjZm0=
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
google.golang.org/appengine v1.2.0 h1:S0iUepdCWODXRvtE+gcRDd15L+k+k1AiHlMiMjefH24=
google.golang.org/appengine v1.2.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=

{
  "schemaVersion": 1,
  "goal": "verify pkg:golang/google.golang.org/appengine@v1.2.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/google.golang.org/appengine@v1.2.0"
  ]
}

package main

import (
	"context"
	"errors"
	"fmt"
	"os"

	"google.golang.org/appengine"
)

func main() {
	validGeo := appengine.GeoPoint{Lat: 37.422, Lng: -122.084}
	if !validGeo.Valid() {
		fmt.Fprintln(os.Stderr, "expected valid GeoPoint to return true")
		os.Exit(1)
	}

	invalidLat := appengine.GeoPoint{Lat: 95.0, Lng: 0.0}
	if invalidLat.Valid() {
		fmt.Fprintln(os.Stderr, "expected out-of-range latitude GeoPoint to return false")
		os.Exit(1)
	}

	invalidLng := appengine.GeoPoint{Lat: 0.0, Lng: -181.0}
	if invalidLng.Valid() {
		fmt.Fprintln(os.Stderr, "expected out-of-range longitude GeoPoint to return false")
		os.Exit(1)
	}

	nsCtx, err := appengine.Namespace(context.Background(), "tenant_01")
	if err != nil || nsCtx == nil {
		fmt.Fprintf(os.Stderr, "expected valid namespace to succeed, got err=%v\n", err)
		os.Exit(1)
	}

	_, err = appengine.Namespace(context.Background(), "invalid/namespace")
	if err == nil {
		fmt.Fprintln(os.Stderr, "expected invalid namespace with slash to fail")
		os.Exit(1)
	}

	var emptyMulti appengine.MultiError
	if emptyMulti.Error() != "(0 errors)" {
		fmt.Fprintf(os.Stderr, "unexpected empty MultiError message: %q\n", emptyMulti.Error())
		os.Exit(1)
	}

	multi := appengine.MultiError{
		nil,
		errors.New("first error"),
		errors.New("second error"),
		errors.New("third error"),
	}
	if multi.Error() != "first error (and 2 other errors)" {
		fmt.Fprintf(os.Stderr, "unexpected MultiError message: %q\n", multi.Error())
		os.Exit(1)
	}

	if appengine.IsDevAppServer() {
		fmt.Fprintln(os.Stderr, "expected IsDevAppServer to be false outside dev server")
		os.Exit(1)
	}
}