From 9c56a167cdb3de1f3981dd1e988bb3069a2f37c5 Mon Sep 17 00:00:00 2001
From: Sergei Zharinov <zharinov@users.noreply.github.com>
Date: Sun, 14 Nov 2021 17:35:27 +0300
Subject: [PATCH] fix(maven): Fetch latest when all releases are unstable
 (#12647)

---
 lib/datasource/maven/index.ts | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/lib/datasource/maven/index.ts b/lib/datasource/maven/index.ts
index acbc41ab7141f6..1a7e6d97acc4fe 100644
--- a/lib/datasource/maven/index.ts
+++ b/lib/datasource/maven/index.ts
@@ -28,13 +28,17 @@ function isStableVersion(x: string): boolean {
   return mavenVersion.isStable(x);
 }
 
-function getLatestStableVersion(releases: Release[]): string | undefined {
-  return releases
-    .map(({ version }) => version)
-    .filter(isStableVersion)
-    .reduce((latestVersion, version) =>
-      compare(version, latestVersion) === 1 ? version : latestVersion
-    );
+function getLatestSuitableVersion(releases: Release[]): string | null {
+  // istanbul ignore if
+  if (!releases?.length) {
+    return null;
+  }
+  const allVersions = releases.map(({ version }) => version);
+  const stableVersions = allVersions.filter(isStableVersion);
+  const versions = stableVersions.length ? stableVersions : allVersions;
+  return versions.reduce((latestVersion, version) =>
+    compare(version, latestVersion) === 1 ? version : latestVersion
+  );
 }
 
 function extractVersions(metadata: XmlDocument): string[] {
@@ -261,10 +265,10 @@ export async function getReleases({
     `Found ${releases.length} new releases for ${dependency.display} in repository ${repoUrl}`
   );
 
-  const latestStableVersion = getLatestStableVersion(releases);
+  const latestSuitableVersion = getLatestSuitableVersion(releases);
   const dependencyInfo =
-    latestStableVersion &&
-    (await getDependencyInfo(dependency, repoUrl, latestStableVersion));
+    latestSuitableVersion &&
+    (await getDependencyInfo(dependency, repoUrl, latestSuitableVersion));
 
   return { ...dependency, ...dependencyInfo, releases };
 }