github.com/beorn7/perks v1.0.1: quantile.Samples

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 github.com/beorn7/perks/quantile.Samples in pkg:golang/github.com/beorn7/perks@v1.0.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/beorn7/perks@v1.0.1
Demonstrate these symbols/APIs:
  - github.com/beorn7/perks/quantile.Samples

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:sha256:5dbaa8ded5387644f2e179bd90544a22926e005b073e7c97555eefeaf3b45977","contract":["quantile.Samples represents a slice of Sample items containing Value, Width, and Delta","quantile.Samples implements sort.Interface methods Len, Less, and Swap","sort.Sort reorders quantile.Samples in ascending order by Value","sort.IsSorted validates sorted order of quantile.Samples","Stream.Samples returns a quantile.Samples slice representing retained stream observations"],"goal":"verify github.com/beorn7/perks/quantile.Samples in pkg:golang/github.com/beorn7/perks@v1.0.1","kind":"HOW","packages":["pkg:golang/github.com/beorn7/perks@v1.0.1"],"schemaVersion":1,"symbols":["github.com/beorn7/perks/quantile.Samples"]},"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/github.com/beorn7/perks@v1.0.1"],"schemaVersion":1,"subject":"pkg:golang/github.com/beorn7/perks@v1.0.1","symbols":["github.com/beorn7/perks/quantile.Samples"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require github.com/beorn7/perks v1.0.1

github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=

package main

import (
	"fmt"
	"sort"

	"github.com/beorn7/perks/quantile"
)

func main() {
	// Construct a quantile.Samples slice directly
	samples := quantile.Samples{
		{Value: 42.0, Width: 1.0, Delta: 0.0},
		{Value: 10.5, Width: 1.0, Delta: 0.0},
		{Value: 99.9, Width: 2.0, Delta: 0.0},
		{Value: 3.14, Width: 1.0, Delta: 0.0},
	}

	fmt.Printf("Initial samples count: %d\n", samples.Len())
	fmt.Printf("Is sorted initially: %v\n", sort.IsSorted(samples))

	// Sort samples using standard library sort.Sort
	sort.Sort(samples)
	fmt.Printf("Is sorted after sort.Sort: %v\n", sort.IsSorted(samples))
	for i, s := range samples {
		fmt.Printf("Sample %d: Value=%.2f Width=%.1f Delta=%.1f\n", i, s.Value, s.Width, s.Delta)
	}

	// Obtain quantile.Samples from an active Stream
	stream := quantile.NewTargeted(map[float64]float64{0.50: 0.01, 0.90: 0.01})
	for i := 1; i <= 100; i++ {
		stream.Insert(float64(i))
	}

	streamSamples := stream.Samples()
	fmt.Printf("Stream retained samples count: %d\n", streamSamples.Len())
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/beorn7/perks/quantile.Samples in pkg:golang/github.com/beorn7/perks@v1.0.1",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/beorn7/perks@v1.0.1"
  ],
  "symbols": [
    "github.com/beorn7/perks/quantile.Samples"
  ]
}

package main

import (
	"fmt"
	"os"
	"sort"

	"github.com/beorn7/perks/quantile"
)

func main() {
	// Assertion 1: quantile.Samples represents a slice of Sample items containing Value, Width, and Delta
	{
		s := quantile.Samples{
			{Value: 15.5, Width: 1.0, Delta: 0.0},
			{Value: 3.2, Width: 2.0, Delta: 0.5},
		}
		if len(s) != 2 {
			fmt.Fprintf(os.Stderr, "assertion 1 failed: expected length 2, got %d\n", len(s))
			os.Exit(1)
		}
		if s[0].Value != 15.5 || s[0].Width != 1.0 || s[0].Delta != 0.0 {
			fmt.Fprintf(os.Stderr, "assertion 1 failed: unexpected sample values at index 0\n")
			os.Exit(1)
		}
		if s[1].Value != 3.2 || s[1].Width != 2.0 || s[1].Delta != 0.5 {
			fmt.Fprintf(os.Stderr, "assertion 1 failed: unexpected sample values at index 1\n")
			os.Exit(1)
		}
	}

	// Assertion 2: quantile.Samples implements sort.Interface methods Len, Less, and Swap
	{
		var _ sort.Interface = quantile.Samples{}
		s := quantile.Samples{
			{Value: 50.0, Width: 1.0, Delta: 0.0},
			{Value: 20.0, Width: 1.0, Delta: 0.0},
			{Value: 80.0, Width: 1.0, Delta: 0.0},
		}
		if s.Len() != 3 {
			fmt.Fprintf(os.Stderr, "assertion 2 failed: expected Len() == 3, got %d\n", s.Len())
			os.Exit(1)
		}
		if s.Less(0, 1) {
			fmt.Fprintf(os.Stderr, "assertion 2 failed: expected Less(0, 1) to be false (50 < 20)\n")
			os.Exit(1)
		}
		if !s.Less(1, 0) {
			fmt.Fprintf(os.Stderr, "assertion 2 failed: expected Less(1, 0) to be true (20 < 50)\n")
			os.Exit(1)
		}
		s.Swap(0, 1)
		if s[0].Value != 20.0 || s[1].Value != 50.0 {
			fmt.Fprintf(os.Stderr, "assertion 2 failed: Swap did not swap elements correctly\n")
			os.Exit(1)
		}
	}

	// Assertion 3: sort.Sort reorders quantile.Samples in ascending order by Value
	{
		s := quantile.Samples{
			{Value: 45.0, Width: 1.0, Delta: 0.0},
			{Value: 12.0, Width: 2.0, Delta: 0.1},
			{Value: 99.0, Width: 1.0, Delta: 0.0},
			{Value: 5.5, Width: 1.0, Delta: 0.0},
			{Value: 33.3, Width: 3.0, Delta: 0.2},
		}
		sort.Sort(s)
		for i := 1; i < len(s); i++ {
			if s[i-1].Value > s[i].Value {
				fmt.Fprintf(os.Stderr, "assertion 3 failed: not sorted at index %d (%f > %f)\n", i, s[i-1].Value, s[i].Value)
				os.Exit(1)
			}
		}
		if s[0].Value != 5.5 || s[len(s)-1].Value != 99.0 {
			fmt.Fprintf(os.Stderr, "assertion 3 failed: unexpected min/max after sort: min=%f, max=%f\n", s[0].Value, s[len(s)-1].Value)
			os.Exit(1)
		}
	}

	// Assertion 4: sort.IsSorted validates sorted order of quantile.Samples
	{
		unsorted := quantile.Samples{
			{Value: 10.0},
			{Value: 5.0},
		}
		if sort.IsSorted(unsorted) {
			fmt.Fprintf(os.Stderr, "assertion 4 failed: unsorted samples reported as sorted\n")
			os.Exit(1)
		}
		sorted := quantile.Samples{
			{Value: 1.0},
			{Value: 2.0},
			{Value: 3.0},
		}
		if !sort.IsSorted(sorted) {
			fmt.Fprintf(os.Stderr, "assertion 4 failed: sorted samples reported as unsorted\n")
			os.Exit(1)
		}
	}

	// Assertion 5: Stream.Samples returns a quantile.Samples slice representing retained stream observations
	{
		stream := quantile.NewTargeted(map[float64]float64{0.50: 0.01})
		for i := 1; i <= 200; i++ {
			stream.Insert(float64(i))
		}
		var samples quantile.Samples = stream.Samples()
		if len(samples) == 0 {
			fmt.Fprintf(os.Stderr, "assertion 5 failed: expected non-empty samples from stream\n")
			os.Exit(1)
		}
		for _, sample := range samples {
			if sample.Value < 1.0 || sample.Value > 200.0 {
				fmt.Fprintf(os.Stderr, "assertion 5 failed: sample value %f out of range [1, 200]\n", sample.Value)
				os.Exit(1)
			}
			if sample.Width <= 0 {
				fmt.Fprintf(os.Stderr, "assertion 5 failed: expected positive sample width, got %f\n", sample.Width)
				os.Exit(1)
			}
		}
	}

	fmt.Println("All contract assertions passed successfully.")
}