From 6af1d9ddee77f43cc6a721974e01f1d69344457f Mon Sep 17 00:00:00 2001
From: Roman <dev@rman.dev>
Date: Wed, 29 Jul 2026 13:30:54 +0100
Subject: [PATCH] feat: add `isPrerelease` (#6)

---
 src/index.ts          | 1 +
 src/version.ts        | 9 +++++++++
 tests/version.test.ts | 5 +++++
 3 files changed, 15 insertions(+)

diff --git a/src/index.ts b/src/index.ts
index a1a2660..8e9d013 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -55,6 +55,7 @@ export {
   getPatch,
   getPrerelease,
   increment,
+  isPrerelease,
   isValid,
   normalize,
   normalizeFull,
diff --git a/src/version.ts b/src/version.ts
index 7d39773..76df825 100644
--- a/src/version.ts
+++ b/src/version.ts
@@ -29,6 +29,15 @@ export function isValid(
   return tryParse(version, options) !== null
 }
 
+export function isPrerelease(
+  version: VersionInput,
+  options: VersionOptions = {},
+): boolean | null {
+  const parsed = tryParse(version, options)
+  if (!parsed) return null
+  return !!parsed.prerelease?.length
+}
+
 export function normalizeFull(
   version: VersionInput,
   options: VersionOptions = {},
diff --git a/tests/version.test.ts b/tests/version.test.ts
index 78fe8ac..6f39777 100644
--- a/tests/version.test.ts
+++ b/tests/version.test.ts
@@ -10,6 +10,7 @@ import {
   getPatch,
   getPrerelease,
   increment,
+  isPrerelease,
   isValid,
   normalize,
   normalizeFull,
@@ -109,6 +110,7 @@ describe('version parsing and accessors', () => {
     version.build = ['next']
 
     expect(isValid(version)).toBe(true)
+    expect(isPrerelease(version)).toBe(true)
     expect(normalizeFull(version)).toBe('1.2.4-beta.1+next')
     expect(normalize(version)).toBe('1.2.4-beta.1')
     expect(clean(version)).toBe('1.2.4-beta.1')
@@ -133,6 +135,7 @@ describe('version parsing and accessors', () => {
     expect(increment(version, 'patch')).toBe('1.2.4')
     expect(getPrerelease(version)).toEqual([])
     expect(getBuild(version)).toEqual([])
+    expect(isPrerelease(version)).toBe(false)
   })
 
   it('accepts every valid node-semver fixture', () => {
@@ -142,6 +145,7 @@ describe('version parsing and accessors', () => {
       const full = `${comparable}${build.length ? `+${build.join('.')}` : ''}`
 
       expect(isValid(version)).toBe(true)
+      expect(isPrerelease(version)).toBe(prerelease.length > 0)
       expect(normalizeFull(version)).toBe(full)
       expect(normalize(version)).toBe(comparable)
       expect(getMajor(version)).toBe(major)
@@ -158,6 +162,7 @@ describe('version parsing and accessors', () => {
       if (typeof version !== 'string') continue
       const options = versionOptions(rawOptions)
       expect(isValid(version, options)).toBe(false)
+      expect(isPrerelease(version, options)).toBeNull()
       expect(normalizeFull(version, options)).toBeNull()
       expect(normalize(version, options)).toBeNull()
     }
-- 
2.51.2