golang.org/x/mod v0.39.0: module.Sort

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/mod/module.Sort in pkg:golang/golang.org/x/mod@v0.39.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/mod@v0.39.0
Demonstrate these symbols/APIs:
  - golang.org/x/mod/module.Sort
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

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:sha256:2a8dd45abcc52c37d074c5c8327d580546b3d1189a0b7b97c03bd4a7a33c660d","contract":["module.Sort sorts a slice of module versions primarily by path and secondarily by semantic version order","module.Sort breaks ties for identical semantic versions using slash suffix comparison","module.Sort handles empty slices and single-element slices without modification or error"],"goal":"verify golang.org/x/mod/module.Sort in pkg:golang/golang.org/x/mod@v0.39.0","kind":"HOW","packages":["pkg:golang/golang.org/x/mod@v0.39.0"],"schemaVersion":1,"symbols":["golang.org/x/mod/module.Sort"]},"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/mod@v0.39.0"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/mod@v0.39.0","symbols":["golang.org/x/mod/module.Sort"],"verifierAdapter":"golang@1"}

module sample-golang-mod

go 1.26.6

require golang.org/x/mod v0.39.0

golang.org/x/mod v0.39.0 h1:UF5zwQdCRRUpHfyPwr7d4UrGiVeldIsogtzWVnczL74=
golang.org/x/mod v0.39.0/go.mod h1:bvIbwjQ0HUFFf5AKukeeYQG4ZBUG9yxQbR9aEweIwYY=

package main

import (
	"fmt"

	"golang.org/x/mod/module"
)

func main() {
	modules := []module.Version{
		{Path: "example.com/b", Version: "v1.1.0"},
		{Path: "example.com/a", Version: "v1.2.0"},
		{Path: "example.com/a", Version: "v1.0.0"},
		{Path: "example.com/a", Version: "v1.2.0/go.mod"},
	}

	fmt.Println("Before sorting:")
	for _, m := range modules {
		fmt.Printf("  %s@%s\n", m.Path, m.Version)
	}

	module.Sort(modules)

	fmt.Println("After sorting:")
	for _, m := range modules {
		fmt.Printf("  %s@%s\n", m.Path, m.Version)
	}
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/mod/module.Sort in pkg:golang/golang.org/x/mod@v0.39.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/mod@v0.39.0"
  ],
  "symbols": [
    "golang.org/x/mod/module.Sort"
  ]
}

package main

import (
	"fmt"
	"os"

	"golang.org/x/mod/module"
)

func main() {
	// Assertion 1: module.Sort sorts a slice of module versions primarily by path and secondarily by semantic version order
	{
		mods := []module.Version{
			{Path: "example.com/z", Version: "v1.0.0"},
			{Path: "example.com/a", Version: "v1.5.0"},
			{Path: "example.com/a", Version: "v1.1.0"},
			{Path: "example.com/a", Version: "v1.2.0-beta.1"},
		}
		module.Sort(mods)

		expected := []module.Version{
			{Path: "example.com/a", Version: "v1.1.0"},
			{Path: "example.com/a", Version: "v1.2.0-beta.1"},
			{Path: "example.com/a", Version: "v1.5.0"},
			{Path: "example.com/z", Version: "v1.0.0"},
		}

		if len(mods) != len(expected) {
			fmt.Fprintf(os.Stderr, "FAIL: sorted slice length mismatch\n")
			os.Exit(1)
		}

		for i := range mods {
			if mods[i] != expected[i] {
				fmt.Fprintf(os.Stderr, "FAIL: at index %d, got %+v, expected %+v\n", i, mods[i], expected[i])
				os.Exit(1)
			}
		}
	}

	// Assertion 2: module.Sort breaks ties for identical semantic versions using slash suffix comparison
	{
		mods := []module.Version{
			{Path: "example.com/pkg", Version: "v1.0.0/go.mod"},
			{Path: "example.com/pkg", Version: "v1.0.0"},
		}
		module.Sort(mods)

		expected := []module.Version{
			{Path: "example.com/pkg", Version: "v1.0.0"},
			{Path: "example.com/pkg", Version: "v1.0.0/go.mod"},
		}

		for i := range mods {
			if mods[i] != expected[i] {
				fmt.Fprintf(os.Stderr, "FAIL: suffix tie-break at index %d: got %+v, expected %+v\n", i, mods[i], expected[i])
				os.Exit(1)
			}
		}
	}

	// Assertion 3: module.Sort handles empty slices and single-element slices without modification or error
	{
		var empty []module.Version
		module.Sort(empty)
		if len(empty) != 0 {
			fmt.Fprintf(os.Stderr, "FAIL: empty slice modified\n")
			os.Exit(1)
		}

		single := []module.Version{{Path: "example.com/single", Version: "v1.0.0"}}
		module.Sort(single)
		if len(single) != 1 || single[0].Path != "example.com/single" || single[0].Version != "v1.0.0" {
			fmt.Fprintf(os.Stderr, "FAIL: single slice modified\n")
			os.Exit(1)
		}
	}

	fmt.Println("PASS: module.Sort contract passed")
}