github.com/google/pprof v0.0.0-20260906184651-6331bc6350fe

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/github.com/google/pprof@v0.0.0-20260906184651-6331bc6350fe
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/google/pprof@v0.0.0-20260906184651-6331bc6350fe

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:sha256:462078292ef9f0f67939b929e426a0cecb5f562ddb0ac3bf10d5459e61918648","contract":["profile.Profile can be created with SampleType and PeriodType","profile.Sample records locations, numeric values, string labels and numeric labels","profile.CheckValid verifies the structural consistency of functions and locations","profile.Write and profile.Parse round-trip profile data with byte fidelity"],"goal":"verify pkg:golang/github.com/google/pprof@v0.0.0-20260906184651-6331bc6350fe","kind":"HOW","packages":["pkg:golang/github.com/google/pprof@v0.0.0-20260906184651-6331bc6350fe"],"schemaVersion":1},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","packageManagerVersion":"1.26.6","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/google/pprof@v0.0.0-20260906184651-6331bc6350fe"],"schemaVersion":1,"subject":"pkg:golang/github.com/google/pprof@v0.0.0-20260906184651-6331bc6350fe","verifierAdapter":"golang@1"}

module sample

go 1.26.6

require github.com/google/pprof v0.0.0-20260906184651-6331bc6350fe

github.com/google/pprof v0.0.0-20260906184651-6331bc6350fe h1:QAinXoAFJdGQYztXn3VpFey7KCwpedbZ/EkzbplQ0cY=
github.com/google/pprof v0.0.0-20260906184651-6331bc6350fe/go.mod h1:jl5iWTm0/hd5PjEYEOuwAJ57L/CibdZfrqZ5XA5GrCk=

{
  "schemaVersion": 1,
  "goal": "verify pkg:golang/github.com/google/pprof@v0.0.0-20260906184651-6331bc6350fe",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/google/pprof@v0.0.0-20260906184651-6331bc6350fe"
  ]
}

package main

import (
	"bytes"
	"fmt"
	"os"

	"github.com/google/pprof/profile"
)

func main() {
	if err := runTests(); err != nil {
		fmt.Fprintf(os.Stderr, "Contract test failed: %v\n", err)
		os.Exit(1)
	}
	fmt.Println("All contract tests passed successfully.")
}

func runTests() error {
	// 1. profile.Profile can be created with SampleType and PeriodType
	p := &profile.Profile{
		SampleType: []*profile.ValueType{
			{Type: "samples", Unit: "count"},
			{Type: "cpu", Unit: "nanoseconds"},
		},
		PeriodType: &profile.ValueType{
			Type: "cpu",
			Unit: "nanoseconds",
		},
		Period: 10000000,
	}

	// 2. profile.Function and profile.Location setup
	fn := &profile.Function{
		ID:         1,
		Name:       "exampleWorker",
		SystemName: "exampleWorker",
		Filename:   "worker.go",
		StartLine:  10,
	}

	loc := &profile.Location{
		ID:      1,
		Address: 0x401000,
		Line: []profile.Line{
			{
				Function: fn,
				Line:     25,
			},
		},
	}

	// 3. profile.Sample records locations, numeric values, string labels and numeric labels
	sample := &profile.Sample{
		Location: []*profile.Location{loc},
		Value:    []int64{1, 5000000},
		Label: map[string][]string{
			"worker_id": {"worker-1"},
		},
		NumLabel: map[string][]int64{
			"bytes_processed": {1024},
		},
		NumUnit: map[string][]string{
			"bytes_processed": {"bytes"},
		},
	}

	p.Function = []*profile.Function{fn}
	p.Location = []*profile.Location{loc}
	p.Sample = []*profile.Sample{sample}

	if !sample.HasLabel("worker_id", "worker-1") {
		return fmt.Errorf("sample.HasLabel(worker_id, worker-1) returned false")
	}
	if len(sample.NumLabel["bytes_processed"]) != 1 || sample.NumLabel["bytes_processed"][0] != 1024 {
		return fmt.Errorf("unexpected NumLabel for bytes_processed")
	}

	// 4. profile.CheckValid verifies the structural consistency of functions and locations
	if err := p.CheckValid(); err != nil {
		return fmt.Errorf("p.CheckValid failed: %w", err)
	}

	// 5. profile.Write and profile.Parse round-trip profile data with byte fidelity
	var buf bytes.Buffer
	if err := p.Write(&buf); err != nil {
		return fmt.Errorf("profile.Write failed: %w", err)
	}

	parsed, err := profile.Parse(&buf)
	if err != nil {
		return fmt.Errorf("profile.Parse failed: %w", err)
	}

	if err := parsed.CheckValid(); err != nil {
		return fmt.Errorf("parsed profile CheckValid failed: %w", err)
	}

	if len(parsed.Sample) != 1 {
		return fmt.Errorf("expected 1 parsed sample, got %d", len(parsed.Sample))
	}
	parsedSample := parsed.Sample[0]
	if len(parsedSample.Value) != 2 || parsedSample.Value[0] != 1 || parsedSample.Value[1] != 5000000 {
		return fmt.Errorf("parsed sample value mismatch: %v", parsedSample.Value)
	}
	if !parsedSample.HasLabel("worker_id", "worker-1") {
		return fmt.Errorf("parsed sample missing label worker_id=worker-1")
	}

	return nil
}