From f38c2a236134a5851740a910ee023ee655b3f228 Mon Sep 17 00:00:00 2001
From: Ben Surgison <ben.surgison@digital.cabinet-office.gov.uk>
Date: Wed, 25 Oct 2023 15:10:42 +0100
Subject: [PATCH] Fix plugin update detection

---
 CHANGELOG.md            |  4 ++++
 lib/plugins/packages.js |  4 ++--
 lib/utils/index.js      | 21 ++++++++++++++++++++-
 lib/utils/utils.test.js | 29 ++++++++++++++++++++++++++++-
 4 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ec41f62a17..307f75d747 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+### Fixes
+
+- [#2364: Fix plugin update detection](https://github.com/alphagov/govuk-prototype-kit/pull/2364)
+
 ## 13.13.5
 
 ### Fixes
diff --git a/lib/plugins/packages.js b/lib/plugins/packages.js
index 95b80327b8..1a889e8a72 100644
--- a/lib/plugins/packages.js
+++ b/lib/plugins/packages.js
@@ -14,7 +14,7 @@ const projectPackage = require(path.join(projectDir, 'package.json'))
 const config = require('../config')
 const { getConfigForPackage } = require('../utils/requestHttps')
 const { getProxyPluginConfig } = require('./plugin-utils')
-const { sortByObjectKey } = require('../utils')
+const { sortByObjectKey, hasNewVersion } = require('../utils')
 
 let packageTrackerInterval
 
@@ -119,7 +119,7 @@ async function refreshPackageInfo (packageName, version) {
     localVersion = path.resolve(installedPackageVersion.replace('file:', ''))
   }
 
-  const updateAvailable = installed && !installedLocally && !installedFromGithub && installedVersion !== latestVersion
+  const updateAvailable = installed && !installedLocally && !installedFromGithub && hasNewVersion(installedVersion, latestVersion)
 
   const pluginDependencies = pluginConfig?.pluginDependencies ? normaliseDependencies(pluginConfig.pluginDependencies) : undefined
 
diff --git a/lib/utils/index.js b/lib/utils/index.js
index 1ffa67d668..cfced2b129 100644
--- a/lib/utils/index.js
+++ b/lib/utils/index.js
@@ -268,6 +268,24 @@ function sortByObjectKey (key) {
   }
 }
 
+function hasNewVersion (installedVersion, latestVersion) {
+  const matcher = /^(\d+)\.(\d+)\.(\d+)(.+)?/
+  const [, installedMajor, installedMinor, installedPatch, installedSuffix] = installedVersion.match(matcher)
+  const [, latestMajor, latestMinor, latestPatch, latestSuffix] = latestVersion.match(matcher)
+
+  if (installedMajor < latestMajor) return true
+  if (installedMajor > latestMajor) return false
+  if (installedMinor < latestMinor) return true
+  if (installedMinor > latestMinor) return false
+  if (installedPatch < latestPatch) return true
+  if (installedPatch > latestPatch) return false
+
+  if (installedSuffix && latestSuffix) {
+    return installedSuffix < latestSuffix
+  }
+  return !!installedSuffix
+}
+
 module.exports = {
   prototypeAppScripts: scripts,
   addNunjucksFilters,
@@ -282,5 +300,6 @@ module.exports = {
   sessionFileStoreQuietLogFn,
   searchAndReplaceFiles,
   recursiveDirectoryContentsSync,
-  sortByObjectKey
+  sortByObjectKey,
+  hasNewVersion
 }
diff --git a/lib/utils/utils.test.js b/lib/utils/utils.test.js
index c54448a790..7bb40c1796 100644
--- a/lib/utils/utils.test.js
+++ b/lib/utils/utils.test.js
@@ -1,5 +1,6 @@
 /* eslint-env jest */
 
+const { sessionFileStoreQuietLogFn, hasNewVersion } = require('./index')
 afterEach(() => {
   jest.useRealTimers()
   jest.restoreAllMocks()
@@ -10,7 +11,6 @@ describe('sessionFileStoreQuietLogFn', () => {
     jest.spyOn(global.console, 'log').mockImplementation()
 
     const SessionFileStore = require('../session-file-store')
-    const { sessionFileStoreQuietLogFn } = require('./index')
 
     jest.useFakeTimers({ doNotFake: ['performance'] })
 
@@ -26,3 +26,30 @@ describe('sessionFileStoreQuietLogFn', () => {
     expect(console.log).not.toHaveBeenCalled()
   })
 })
+
+describe('hasNewVersion', () => {
+  [
+    { installed: '13.1.0', latest: '13.1.0', result: false },
+    { installed: '13.1.1', latest: '13.1.0', result: false },
+    { installed: '13.2.0', latest: '13.1.0', result: false },
+    { installed: '14.1.0', latest: '13.1.0', result: false },
+    { installed: '13.1.0', latest: '13.1.1', result: true },
+    { installed: '13.1.0', latest: '13.2.0', result: true },
+    { installed: '13.1.0', latest: '14.1.0', result: true },
+    { installed: '13.2.4-rc1', latest: '13.2.4-rc1', result: false },
+    { installed: '13.2.3-rc1', latest: '13.2.4-rc1', result: true },
+    { installed: '13.2.4-rc1', latest: '13.2.4-rc2', result: true },
+    { installed: '13.2.4-rc1', latest: '13.2.4', result: true },
+    { installed: '13.2.4', latest: '13.2.4-rc1', result: false },
+    { installed: '5.0.0-internal.0', latest: '4.7.0', result: false },
+    { installed: '4.7.0', latest: '5.0.0-internal.0', result: true },
+    { installed: '4.7.0-internal.0', latest: '5.0.0', result: true },
+    { installed: '5.0.0', latest: '4.7.0-internal.0', result: false }
+  ].forEach(({
+    installed,
+    latest,
+    result
+  }) => it(`should return ${result} when installed version is ${installed} and latest version is ${latest}`, () => {
+    expect(hasNewVersion(installed, latest)).toEqual(result)
+  }))
+})