feat: add option to disable cache pruning

README.md

@@ -166,6 +166,20 @@ It defaults to `setup-uv-cache` in the `TMP` dir, `D:\a\_temp\uv-tool-dir` on Wi
     cache-local-path: "/path/to/cache"
 ```
 
+### Disable cache pruning
+
+By default, the cache is pruned after a run, which means that all pre-built wheels are removed from
+the cache ([documentation](https://docs.astral.sh/uv/concepts/cache/#caching-in-continuous-integration)).
+If you want to keep the cache after a run, you can disable cache pruning with the `prune-cache` input.
+
+```yaml
+- name: Don't prune the cache before saving it
+  uses: astral-sh/setup-uv@v3
+  with:
+    enable-cache: true
+    prune-cache: false
+```
+
 ### GitHub authentication token
 
 This action uses the GitHub API to fetch the uv release artifacts. To avoid hitting the GitHub API

action.yml

@@ -29,6 +29,9 @@ inputs:
   cache-local-path:
     description: "Local path to store the cache."
     default: ""
+  prune-cache:
+    description: "Prune cache before saving."
+    default: true
   tool-dir:
     description: "Custom path to set UV_TOOL_DIR to."
     required: false

src/save-cache.ts

@@ -5,7 +5,7 @@ import {
   STATE_CACHE_MATCHED_KEY,
   STATE_CACHE_KEY,
 } from "./cache/restore-cache";
-import { cacheLocalPath, enableCache } from "./utils/inputs";
+import { cacheLocalPath, enableCache, pruneCache as pruneCacheOption } from "./utils/inputs";
 
 export async function run(): Promise<void> {
   try {
@@ -32,7 +32,9 @@ async function saveCache(): Promise<void> {
     return;
   }
 
-  await pruneCache();
+  if (pruneCacheOption) {
+    await pruneCache();
+  }
 
   core.info(`Saving cache path: ${cacheLocalPath}`);
   await cache.saveCache([cacheLocalPath], cacheKey);

src/utils/inputs.ts

@@ -7,6 +7,7 @@ export const enableCache = core.getInput("enable-cache") === "true";
 export const cacheSuffix = core.getInput("cache-suffix") || "";
 export const cacheLocalPath = getCacheLocalPath();
 export const cacheDependencyGlob = core.getInput("cache-dependency-glob");
+export const pruneCache = (core.getInput("prune-cache") || "true") === "true";
 export const toolBinDir = getToolBinDir();
 export const toolDir = getToolDir();
 export const githubToken = core.getInput("github-token");