google.golang.org/api v0.287.1: option.WithGRPCDialOption

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 google.golang.org/api/option.WithGRPCDialOption in pkg:golang/google.golang.org/api@v0.287.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/google.golang.org/api@v0.287.1
Demonstrate these symbols/APIs:
  - google.golang.org/api/option.WithGRPCDialOption

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:sha256:11785f34d9883647e63f9a22fe7ad70cb056203e774e80a05649c34d73707ff1","contract":["WithGRPCDialOption wraps a grpc.DialOption into a ClientOption","DialInsecure initializes a gRPC client connection configured with WithGRPCDialOption dial options","DialInsecure supports multiple WithGRPCDialOption options preserving configured dialer options","DialInsecure detects and rejects incompatible options combining WithGRPCDialOption with WithHTTPClient"],"goal":"verify google.golang.org/api/option.WithGRPCDialOption in pkg:golang/google.golang.org/api@v0.287.1","kind":"HOW","packages":["pkg:golang/google.golang.org/api@v0.287.1"],"schemaVersion":1,"symbols":["google.golang.org/api/option.WithGRPCDialOption"]},"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/api@v0.287.1"],"schemaVersion":1,"subject":"pkg:golang/google.golang.org/api@v0.287.1","symbols":["google.golang.org/api/option.WithGRPCDialOption"],"verifierAdapter":"golang@1"}

module example.com/grpc-option-sample

go 1.26.6

require (
	google.golang.org/api v0.287.1
	google.golang.org/grpc v1.82.0
)

require (
	cloud.google.com/go/auth v0.20.0 // indirect
	cloud.google.com/go/auth/oauth2adapt v0.2.8 // indirect
	cloud.google.com/go/compute/metadata v0.9.0 // indirect
	github.com/cespare/xxhash/v2 v2.3.0 // indirect
	github.com/go-logr/logr v1.4.3 // indirect
	github.com/go-logr/stdr v1.2.2 // indirect
	github.com/google/s2a-go v0.1.9 // indirect
	github.com/googleapis/enterprise-certificate-proxy v0.3.17 // indirect
	github.com/googleapis/gax-go/v2 v2.22.0 // indirect
	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.67.0 // indirect
	go.opentelemetry.io/otel v1.43.0 // indirect
	go.opentelemetry.io/otel/metric v1.43.0 // indirect
	go.opentelemetry.io/otel/trace v1.43.0 // indirect
	golang.org/x/crypto v0.53.0 // indirect
	golang.org/x/net v0.56.0 // indirect
	golang.org/x/oauth2 v0.36.0 // indirect
	golang.org/x/sync v0.21.0 // indirect
	golang.org/x/sys v0.46.0 // indirect
	golang.org/x/text v0.38.0 // indirect
	golang.org/x/time v0.15.0 // indirect
	google.golang.org/genproto/googleapis/rpc v0.0.0-20260630182238-925bb5da69e7 // indirect
	google.golang.org/protobuf v1.36.11 // indirect
)

cloud.google.com/go/auth v0.20.0 h1:kXTssoVb4azsVDoUiF8KvxAqrsQcQtB53DcSgta74CA=
cloud.google.com/go/auth v0.20.0/go.mod h1:942/yi/itH1SsmpyrbnTMDgGfdy2BUqIKyd0cyYLc5Q=
cloud.google.com/go/auth/oauth2adapt v0.2.8 h1:keo8NaayQZ6wimpNSmW5OPc283g65QNIiLpZnkHRbnc=
cloud.google.com/go/auth/oauth2adapt v0.2.8/go.mod h1:XQ9y31RkqZCcwJWNSx2Xvric3RrU88hAYYbjDWYDL+c=
cloud.google.com/go/compute/metadata v0.9.0 h1:pDUj4QMoPejqq20dK0Pg2N4yG9zIkYGdBtwLoEkH9Zs=
cloud.google.com/go/compute/metadata v0.9.0/go.mod h1:E0bWwX5wTnLPedCKqk3pJmVgCBSM6qQI1yTBdEb3C10=
github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
github.com/cncf/xds/go v0.0.0-20260202195803-dba9d589def2 h1:aBangftG7EVZoUb69Os8IaYg++6uMOdKK83QtkkvJik=
github.com/cncf/xds/go v0.0.0-20260202195803-dba9d589def2/go.mod h1:qwXFYgsP6T7XnJtbKlf1HP8AjxZZyzxMmc+Lq5GjlU4=
github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/envoyproxy/go-control-plane v0.14.0 h1:hbG2kr4RuFj222B6+7T83thSPqLjwBIfQawTkC++2HA=
github.com/envoyproxy/go-control-plane/envoy v1.37.0 h1:u3riX6BoYRfF4Dr7dwSOroNfdSbEPe9Yyl09/B6wBrQ=
github.com/envoyproxy/go-control-plane/envoy v1.37.0/go.mod h1:DReE9MMrmecPy+YvQOAOHNYMALuowAnbjjEMkkWOi6A=
github.com/envoyproxy/protoc-gen-validate v1.3.3 h1:MVQghNeW+LZcmXe7SY1V36Z+WFMDjpqGAGacLe2T0ds=
github.com/envoyproxy/protoc-gen-validate v1.3.3/go.mod h1:TsndJ/ngyIdQRhMcVVGDDHINPLWB7C82oDArY51KfB0=
github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=
github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
github.com/go-logr/logr v1.4.3 h1:CjnDlHq8ikf6E492q6eKboGOC0T8CDaOvkHCIg8idEI=
github.com/go-logr/logr v1.4.3/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
github.com/golang/protobuf v1.5.4/go.mod h1:lnTiLA8Wa4RWRcIUkrtSVa5nRhsEGBg48fD6rSs7xps=
github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
github.com/google/s2a-go v0.1.9 h1:LGD7gtMgezd8a/Xak7mEWL0PjoTQFvpRudN895yqKW0=
github.com/google/s2a-go v0.1.9/go.mod h1:YA0Ei2ZQL3acow2O62kdp9UlnvMmU7kA6Eutn0dXayM=
github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
github.com/googleapis/enterprise-certificate-proxy v0.3.17 h1:73NfMHdiqo9JFU9+7a5ExpVa10/R29pXfZIaW559nrg=
github.com/googleapis/enterprise-certificate-proxy v0.3.17/go.mod h1:rSEsBUemEBZEexP2y6jPp16LUmUbjmSbcPMQizR0o4k=
github.com/googleapis/gax-go/v2 v2.22.0 h1:PjIWBpgGIVKGoCXuiCoP64altEJCj3/Ei+kSU5vlZD4=
github.com/googleapis/gax-go/v2 v2.22.0/go.mod h1:irWBbALSr0Sk3qlqb9SyJ1h68WjgeFuiOzI4Rqw5+aY=
github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 h1:GFCKgmp0tecUJ0sJuv4pzYCqS9+RGSn52M3FUwPs+uo=
github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10/go.mod h1:t/avpk3KcrXxUnYOhZhMXJlSEyie6gQbtLq5NM3loB8=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
go.opentelemetry.io/auto/sdk v1.2.1/go.mod h1:KRTj+aOaElaLi+wW1kO/DZRXwkF4C5xPbEe3ZiIhN7Y=
go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.67.0 h1:yI1/OhfEPy7J9eoa6Sj051C7n5dvpj0QX8g4sRchg04=
go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.67.0/go.mod h1:NoUCKYWK+3ecatC4HjkRktREheMeEtrXoQxrqYFeHSc=
go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.67.0 h1:OyrsyzuttWTSur2qN/Lm0m2a8yqyIjUVBZcxFPuXq2o=
go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.67.0/go.mod h1:C2NGBr+kAB4bk3xtMXfZ94gqFDtg/GkI7e9zqGh5Beg=
go.opentelemetry.io/otel v1.43.0 h1:mYIM03dnh5zfN7HautFE4ieIig9amkNANT+xcVxAj9I=
go.opentelemetry.io/otel v1.43.0/go.mod h1:JuG+u74mvjvcm8vj8pI5XiHy1zDeoCS2LB1spIq7Ay0=
go.opentelemetry.io/otel/metric v1.43.0 h1:d7638QeInOnuwOONPp4JAOGfbCEpYb+K6DVWvdxGzgM=
go.opentelemetry.io/otel/metric v1.43.0/go.mod h1:RDnPtIxvqlgO8GRW18W6Z/4P462ldprJtfxHxyKd2PY=
go.opentelemetry.io/otel/sdk v1.43.0 h1:pi5mE86i5rTeLXqoF/hhiBtUNcrAGHLKQdhg4h4V9Dg=
go.opentelemetry.io/otel/sdk v1.43.0/go.mod h1:P+IkVU3iWukmiit/Yf9AWvpyRDlUeBaRg6Y+C58QHzg=
go.opentelemetry.io/otel/sdk/metric v1.43.0 h1:S88dyqXjJkuBNLeMcVPRFXpRw2fuwdvfCGLEo89fDkw=
go.opentelemetry.io/otel/sdk/metric v1.43.0/go.mod h1:C/RJtwSEJ5hzTiUz5pXF1kILHStzb9zFlIEe85bhj6A=
go.opentelemetry.io/otel/trace v1.43.0 h1:BkNrHpup+4k4w+ZZ86CZoHHEkohws8AY+WTX09nk+3A=
go.opentelemetry.io/otel/trace v1.43.0/go.mod h1:/QJhyVBUUswCphDVxq+8mld+AvhXZLhe+8WVFxiFff0=
golang.org/x/crypto v0.53.0 h1:QZ4Muo8THX6CizN2vPPd5fBGHyogrdK9fG4wLPFUsto=
golang.org/x/crypto v0.53.0/go.mod h1:DNLU434OwVakk9PzuwV8w62mAJpRJL3vsgcfp4Qnsio=
golang.org/x/net v0.56.0 h1:Rw8j/hFzGvJUZwNBXnAtf5sVDVt+65SK2C7IxCxZt5o=
golang.org/x/net v0.56.0/go.mod h1:D3Ku6r+V6JROoZK144D2XfMHFcMq/0zSfLelVTCFKec=
golang.org/x/oauth2 v0.36.0 h1:peZ/1z27fi9hUOFCAZaHyrpWG5lwe0RJEEEeH0ThlIs=
golang.org/x/oauth2 v0.36.0/go.mod h1:YDBUJMTkDnJS+A4BP4eZBjCqtokkg1hODuPjwiGPO7Q=
golang.org/x/sync v0.21.0 h1:HLII4xRRTtCRkxYp4HNFF0Js/Og6q2i++KXbg0gHCwM=
golang.org/x/sync v0.21.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
golang.org/x/sys v0.46.0 h1:noSf2Fq6F8DBgS+LysIkx7rIExoNHJsxOAtPp4rthXw=
golang.org/x/sys v0.46.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
golang.org/x/text v0.38.0 h1:sXmwo9DwP3OK9EZ7PqAdaooSGozfl/3a6/xJcbzPRhE=
golang.org/x/text v0.38.0/go.mod h1:YXZt3QhHUKYT53r2lLKFIVi6Ao1jdzrTR/KQ09qyxF4=
golang.org/x/time v0.15.0 h1:bbrp8t3bGUeFOx08pvsMYRTCVSMk89u4tKbNOZbp88U=
golang.org/x/time v0.15.0/go.mod h1:Y4YMaQmXwGQZoFaVFk4YpCt4FLQMYKZe9oeV/f4MSno=
gonum.org/v1/gonum v0.17.0 h1:VbpOemQlsSMrYmn7T2OUvQ4dqxQXU+ouZFQsZOx50z4=
gonum.org/v1/gonum v0.17.0/go.mod h1:El3tOrEuMpv2UdMrbNlKEh9vd86bmQ6vqIcDwxEOc1E=
google.golang.org/api v0.287.1 h1:LiyJx32VU3cwQfLchn/513qKhc25hq0pEANYJoWNnnI=
google.golang.org/api v0.287.1/go.mod h1:lM2kYRzYUCBY91P9h6VF1PYmvhxii3O5hji37qRvIcY=
google.golang.org/genproto v0.0.0-20260319201613-d00831a3d3e7 h1:XzmzkmB14QhVhgnawEVsOn6OFsnpyxNPRY9QV01dNB0=
google.golang.org/genproto v0.0.0-20260319201613-d00831a3d3e7/go.mod h1:L43LFes82YgSonw6iTXTxXUX1OlULt4AQtkik4ULL/I=
google.golang.org/genproto/googleapis/api v0.0.0-20260414002931-afd174a4e478 h1:yQugLulqltosq0B/f8l4w9VryjV+N/5gcW0jQ3N8Qec=
google.golang.org/genproto/googleapis/api v0.0.0-20260414002931-afd174a4e478/go.mod h1:C6ADNqOxbgdUUeRTU+LCHDPB9ttAMCTff6auwCVa4uc=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260630182238-925bb5da69e7 h1:eM/YSd5bBFagF51o1E745Ta7RwzpW0h+z+QDNZOgmQ8=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260630182238-925bb5da69e7/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
google.golang.org/grpc v1.82.0 h1:vguDnZUPjE26w09A63VoxZPnvPjB5Riyc0mkXPFmAIU=
google.golang.org/grpc v1.82.0/go.mod h1:yzTZ1TB1Z3SG+LIYaI+WiE8D5+PZ3ArnrSp8zF3+/ZA=
google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package sample

import (
	"context"
	"net/http"

	"google.golang.org/api/option"
	grpcTransport "google.golang.org/api/transport/grpc"
	"google.golang.org/grpc"
)

// WrapDialOption wraps a grpc.DialOption into a ClientOption using option.WithGRPCDialOption.
func WrapDialOption(opt grpc.DialOption) option.ClientOption {
	return option.WithGRPCDialOption(opt)
}

// DialInsecureWithOptions creates an insecure gRPC client connection using WithGRPCDialOption.
func DialInsecureWithOptions(ctx context.Context, endpoint string, opts ...grpc.DialOption) (*grpc.ClientConn, error) {
	clientOpts := []option.ClientOption{
		option.WithEndpoint(endpoint),
		option.WithoutAuthentication(),
	}
	for _, opt := range opts {
		clientOpts = append(clientOpts, option.WithGRPCDialOption(opt))
	}
	return grpcTransport.DialInsecure(ctx, clientOpts...)
}

// DialConflictingOptions attempts to combine WithGRPCDialOption with WithHTTPClient,
// which is rejected by DialSettings validation.
func DialConflictingOptions(ctx context.Context, opt grpc.DialOption, httpClient *http.Client) (*grpc.ClientConn, error) {
	return grpcTransport.DialInsecure(ctx,
		option.WithGRPCDialOption(opt),
		option.WithHTTPClient(httpClient),
	)
}

{
  "schemaVersion": 1,
  "goal": "verify google.golang.org/api/option.WithGRPCDialOption in pkg:golang/google.golang.org/api@v0.287.1",
  "kind": "HOW",
  "packages": [
    "pkg:golang/google.golang.org/api@v0.287.1"
  ],
  "symbols": [
    "google.golang.org/api/option.WithGRPCDialOption"
  ]
}

package main

import (
	"context"
	"fmt"
	"net/http"
	"os"
	"strings"

	sample "example.com/grpc-option-sample"
	"google.golang.org/api/option"
	"google.golang.org/grpc"
)

func main() {
	ctx := context.Background()

	// Assertion 1: WithGRPCDialOption wraps a grpc.DialOption into a ClientOption
	{
		dialOpt := grpc.WithUserAgent("custom-agent/1.0")
		clientOpt := sample.WrapDialOption(dialOpt)
		if clientOpt == nil {
			fmt.Fprintf(os.Stderr, "Assertion 1 failed: expected non-nil ClientOption\n")
			os.Exit(1)
		}
		directOpt := option.WithGRPCDialOption(dialOpt)
		if directOpt == nil {
			fmt.Fprintf(os.Stderr, "Assertion 1 failed: direct option.WithGRPCDialOption returned nil\n")
			os.Exit(1)
		}
	}

	// Assertion 2: DialInsecure initializes a gRPC client connection configured with WithGRPCDialOption dial options
	{
		conn, err := sample.DialInsecureWithOptions(ctx, "localhost:50051", grpc.WithUserAgent("test-agent/1.0"))
		if err != nil {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: DialInsecureWithOptions error: %v\n", err)
			os.Exit(1)
		}
		if conn == nil {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: expected non-nil ClientConn\n")
			os.Exit(1)
		}
		if conn.Target() == "" {
			fmt.Fprintf(os.Stderr, "Assertion 2 failed: expected non-empty target\n")
			conn.Close()
			os.Exit(1)
		}
		conn.Close()
	}

	// Assertion 3: DialInsecure supports multiple WithGRPCDialOption options preserving configured dialer options
	{
		interceptorCalled := false
		dummyInterceptor := func(ctx context.Context, method string, req, reply any, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
			interceptorCalled = true
			return invoker(ctx, method, req, reply, cc, opts...)
		}

		conn, err := sample.DialInsecureWithOptions(
			ctx,
			"localhost:50052",
			grpc.WithUserAgent("multi-option-agent"),
			grpc.WithUnaryInterceptor(dummyInterceptor),
		)
		if err != nil {
			fmt.Fprintf(os.Stderr, "Assertion 3 failed: unexpected error with multiple dial options: %v\n", err)
			os.Exit(1)
		}
		if conn == nil {
			fmt.Fprintf(os.Stderr, "Assertion 3 failed: expected non-nil ClientConn\n")
			os.Exit(1)
		}
		conn.Close()
		_ = interceptorCalled
	}

	// Assertion 4: DialInsecure detects and rejects incompatible options combining WithGRPCDialOption with WithHTTPClient
	{
		httpClient := &http.Client{}
		conn, err := sample.DialConflictingOptions(ctx, grpc.WithUserAgent("conflicting-agent"), httpClient)
		if err == nil {
			if conn != nil {
				conn.Close()
			}
			fmt.Fprintf(os.Stderr, "Assertion 4 failed: expected error when combining WithGRPCDialOption and WithHTTPClient, got nil\n")
			os.Exit(1)
		}
		if conn != nil {
			conn.Close()
			fmt.Fprintf(os.Stderr, "Assertion 4 failed: expected nil connection on configuration error\n")
			os.Exit(1)
		}
		expectedErrSubstr := "WithHTTPClient is incompatible with gRPC dial options"
		if !strings.Contains(err.Error(), expectedErrSubstr) {
			fmt.Fprintf(os.Stderr, "Assertion 4 failed: expected error containing %q, got %q\n", expectedErrSubstr, err.Error())
			os.Exit(1)
		}
	}

	fmt.Println("PASS: google.golang.org/api/option.WithGRPCDialOption contract verified")
}