github.com/rogpeppe/go-internal v1.3.0: semver.IsValid

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/rogpeppe/go-internal/semver.IsValid in pkg:golang/github.com/rogpeppe/go-internal@v1.3.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/rogpeppe/go-internal@v1.3.0
Demonstrate these symbols/APIs:
  - github.com/rogpeppe/go-internal/semver.IsValid

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:sha256:66e9b16325a828e288eeb5b9da37f94aba3d46c0d5c749f6a20187b5ddc6f9f2","contract":["semver.IsValid returns true for standard semantic version strings with a leading 'v'","semver.IsValid returns true for short-form versions vMAJOR and vMAJOR.MINOR without prereleases","semver.IsValid returns true for semantic versions containing prerelease and build metadata","semver.IsValid returns false for semantic version strings lacking the leading 'v'","semver.IsValid returns false for malformed version strings and strings with leading zeros"],"goal":"verify github.com/rogpeppe/go-internal/semver.IsValid in pkg:golang/github.com/rogpeppe/go-internal@v1.3.0","kind":"HOW","packages":["pkg:golang/github.com/rogpeppe/go-internal@v1.3.0"],"schemaVersion":1,"symbols":["github.com/rogpeppe/go-internal/semver.IsValid"]},"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/rogpeppe/go-internal@v1.3.0"],"schemaVersion":1,"subject":"pkg:golang/github.com/rogpeppe/go-internal@v1.3.0","symbols":["github.com/rogpeppe/go-internal/semver.IsValid"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require github.com/rogpeppe/go-internal v1.3.0

github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
github.com/rogpeppe/go-internal v1.3.0 h1:RR9dF3JtopPvtkroDZuVD7qquD0bnHlKSqaQhgwt8yk=
github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=

package main

import (
	"fmt"

	"github.com/rogpeppe/go-internal/semver"
)

func main() {
	versions := []string{
		"v1.2.3",
		"v1",
		"1.2.3",
		"v1.0.0-beta.1+build1",
	}
	for _, v := range versions {
		fmt.Printf("semver.IsValid(%q) = %v\n", v, semver.IsValid(v))
	}
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/rogpeppe/go-internal/semver.IsValid in pkg:golang/github.com/rogpeppe/go-internal@v1.3.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/rogpeppe/go-internal@v1.3.0"
  ],
  "symbols": [
    "github.com/rogpeppe/go-internal/semver.IsValid"
  ]
}

package main

import (
	"fmt"
	"os"

	"github.com/rogpeppe/go-internal/semver"
)

func main() {
	// Assertion 1: semver.IsValid returns true for canonical semantic versions with leading 'v'
	{
		validStandard := []string{"v0.0.0", "v1.0.0", "v1.2.3", "v10.20.30"}
		for _, v := range validStandard {
			if !semver.IsValid(v) {
				fmt.Fprintf(os.Stderr, "Assertion 1 failed: expected semver.IsValid(%q) to be true, got false\n", v)
				os.Exit(1)
			}
		}
	}

	// Assertion 2: semver.IsValid returns true for short-form versions vMAJOR and vMAJOR.MINOR without prereleases
	{
		validShorthands := []string{"v1", "v2", "v1.2", "v10.5"}
		for _, v := range validShorthands {
			if !semver.IsValid(v) {
				fmt.Fprintf(os.Stderr, "Assertion 2 failed: expected semver.IsValid(%q) to be true, got false\n", v)
				os.Exit(1)
			}
		}
	}

	// Assertion 3: semver.IsValid returns true for valid semantic versions with prerelease identifiers and alphanumeric build metadata
	{
		validWithMeta := []string{
			"v1.0.0-alpha",
			"v1.0.0-alpha.1",
			"v1.0.0-0.3.7",
			"v1.0.0-x.7.z.92",
			"v1.0.0-alpha+001",
			"v1.0.0+20130313144700",
			"v1.0.0-beta+build123",
		}
		for _, v := range validWithMeta {
			if !semver.IsValid(v) {
				fmt.Fprintf(os.Stderr, "Assertion 3 failed: expected semver.IsValid(%q) to be true, got false\n", v)
				os.Exit(1)
			}
		}
	}

	// Assertion 4: semver.IsValid returns false for versions missing the leading 'v'
	{
		missingV := []string{"1.0.0", "1.2.3", "0.0.1", "2.0.0-alpha"}
		for _, v := range missingV {
			if semver.IsValid(v) {
				fmt.Fprintf(os.Stderr, "Assertion 4 failed: expected semver.IsValid(%q) to be false (missing 'v'), got true\n", v)
				os.Exit(1)
			}
		}
	}

	// Assertion 5: semver.IsValid returns false for malformed versions, leading zeros in numbers, or four-part versions
	{
		invalidVersions := []string{
			"",
			"v",
			"v1.2.3.4",
			"v01.2.3",
			"v1.02.3",
			"v1.2.03",
			"v1.2.3-01",
			"v1.2.3+invalid character",
			"not-a-version",
		}
		for _, v := range invalidVersions {
			if semver.IsValid(v) {
				fmt.Fprintf(os.Stderr, "Assertion 5 failed: expected semver.IsValid(%q) to be false, got true\n", v)
				os.Exit(1)
			}
		}
	}

	fmt.Println("PASS: all semver.IsValid contract assertions passed")
}