Use latest version from manifest-file (#458)

If a manifest-file is supplied the default value of the version input
(latest) will get the latest version available in the manifest. That
might not be the actual latest version available in the official uv
repo.

src/download/download-version.ts

@@ -7,7 +7,10 @@ import { OWNER, REPO, TOOL_CACHE_NAME } from "../utils/constants";
 import type { Architecture, Platform } from "../utils/platforms";
 import { validateChecksum } from "./checksum/checksum";
 import { Octokit } from "../utils/octokit";
-import { getDownloadUrl } from "./version-manifest";
+import {
+  getDownloadUrl,
+  getLatestKnownVersion as getLatestVersionInManifest,
+} from "./version-manifest";
 
 export function tryGetFromToolCache(
   arch: Architecture,
@@ -127,13 +130,22 @@ function getExtension(platform: Platform): string {
 
 export async function resolveVersion(
   versionInput: string,
+  manifestFile: string | undefined,
   githubToken: string,
 ): Promise<string> {
   core.debug(`Resolving version: ${versionInput}`);
-  const version =
-    versionInput === "latest"
-      ? await getLatestVersion(githubToken)
-      : versionInput;
+  let version: string;
+  if (manifestFile) {
+    version =
+      versionInput === "latest"
+        ? await getLatestVersionInManifest(manifestFile)
+        : versionInput;
+  } else {
+    version =
+      versionInput === "latest"
+        ? await getLatestVersion(githubToken)
+        : versionInput;
+  }
   if (tc.isExplicitVersion(version)) {
     core.debug(`Version ${version} is an explicit version.`);
     return version;