Change some formulations in README.md (#164)

Can be disabled by setting `ignore-nothing-to-cache: true`

.github/workflows/test-cache.yml

@@ -21,7 +21,7 @@ jobs:
         uses: ./
         with:
           enable-cache: true
-          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}
+          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}-test-setup-cache
       - run: uv sync
         working-directory: __tests__/fixtures/uv-project
   test-restore-cache:
@@ -37,7 +37,7 @@ jobs:
         uses: ./
         with:
           enable-cache: true
-          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}
+          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}-test-setup-cache
       - name: Cache was hit
         run: |
           if [ "$CACHE_HIT" != "true" ]; then
@@ -59,7 +59,7 @@ jobs:
           cache-dependency-glob: |
             __tests__/fixtures/uv-project/uv.lock
             **/pyproject.toml
-          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}
+          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}-test-setup-cache-dependency-glob
       - run: uv sync
         working-directory: __tests__/fixtures/uv-project
   test-restore-cache-dependency-glob:
@@ -79,7 +79,8 @@ jobs:
           cache-dependency-glob: |
             __tests__/fixtures/uv-project/uv.lock
             **/pyproject.toml
-          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}
+          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}-test-setup-cache-dependency-glob
+          ignore-nothing-to-cache: true
       - name: Cache was not hit
         run: |
           if [ "$CACHE_HIT" == "true" ]; then
@@ -96,7 +97,7 @@ jobs:
         uses: ./
         with:
           enable-cache: true
-          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}
+          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}-test-setup-cache-local
           cache-local-path: /tmp/uv-cache
       - run: uv sync
         working-directory: __tests__/fixtures/uv-project
@@ -110,7 +111,7 @@ jobs:
         uses: ./
         with:
           enable-cache: true
-          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}
+          cache-suffix: ${{ github.run_id }}-${{ github.run_attempt }}-test-setup-cache-local
           cache-local-path: /tmp/uv-cache
       - name: Cache was hit
         run: |
@@ -122,38 +123,38 @@ jobs:
       - run: uv sync
         working-directory: __tests__/fixtures/uv-project
 
-  prepare-tilde-expansion-tests:
+  test-tilde-expansion-cache-local-path:
     runs-on: selfhosted-ubuntu-arm64
     steps:
+      - uses: actions/checkout@v4
+      - name: Create cache directory
+        run: mkdir -p ~/uv-cache
+        shell: bash
+      - name: Setup with cache
+        uses: ./
+        with:
+          cache-local-path: ~/uv-cache/cache-local-path
+      - run: uv sync
+        working-directory: __tests__/fixtures/uv-project
+
+  test-tilde-expansion-cache-dependency-glob:
+    runs-on: selfhosted-ubuntu-arm64
+    steps:
+      - uses: actions/checkout@v4
       - name: Create cache directory
         run: mkdir -p ~/uv-cache
         shell: bash
       - name: Create cache dependency glob file
         run: touch ~/uv-cache.glob
         shell: bash
-
-  test-tilde-expansion-cache-local-path:
-    needs: prepare-tilde-expansion-tests
-    runs-on: selfhosted-ubuntu-arm64
-    steps:
-      - uses: actions/checkout@v4
-      - name: Setup with cache
-        uses: ./
-        with:
-          enable-cache: true
-          cache-local-path: ~/uv-cache/cache-local-path
-
-  test-tilde-expansion-cache-dependency-glob:
-    needs: prepare-tilde-expansion-tests
-    runs-on: selfhosted-ubuntu-arm64
-    steps:
-      - uses: actions/checkout@v4
       - name: Setup with cache
         uses: ./
         with:
           enable-cache: true
           cache-local-path: ~/uv-cache/cache-dependency-glob
           cache-dependency-glob: "~/uv-cache.glob"
+      - run: uv sync
+        working-directory: __tests__/fixtures/uv-project
 
   cleanup-tilde-expansion-tests:
     needs:

README.md

@@ -18,6 +18,8 @@ Set up your GitHub Actions workflow with a specific version of [uv](https://docs
   - [Enable Caching](#enable-caching)
     - [Cache dependency glob](#cache-dependency-glob)
   - [Local cache path](#local-cache-path)
+  - [Disable cache pruning](#disable-cache-pruning)
+  - [Ignore nothing to cache](#ignore-nothing-to-cache)
   - [GitHub authentication token](#github-authentication-token)
   - [UV_TOOL_DIR](#uv_tool_dir)
   - [UV_TOOL_BIN_DIR](#uv_tool_bin_dir)
@@ -41,7 +43,7 @@ For an example workflow, see
 
 > [!TIP]
 >
-> Using `latest` requires that uv download the executable on every run, which incurs a cost
+> Using `latest` requires to download the uv executable on every run, which incurs a cost
 > (especially on self-hosted runners). As a best practice, consider pinning the version to a
 > specific release.
 
@@ -56,7 +58,7 @@ For an example workflow, see
 
 ### Install a version by supplying a semver range
 
-You can also specify a [semver range](https://github.com/npm/node-semver?tab=readme-ov-file#ranges)
+You can specify a [semver range](https://github.com/npm/node-semver?tab=readme-ov-file#ranges)
 to install the latest version that satisfies the range.
 
 ```yaml
@@ -75,7 +77,7 @@ to install the latest version that satisfies the range.
 
 ### Validate checksum
 
-You can also specify a checksum to validate the downloaded file. Checksums up to the default version
+You can specify a checksum to validate the downloaded executable. Checksums up to the default version
 are automatically verified by this action. The sha256 hashes can be found on the
 [releases page](https://github.com/astral-sh/uv/releases) of the uv repo.
 
@@ -89,8 +91,8 @@ are automatically verified by this action. The sha256 hashes can be found on the
 
 ### Enable caching
 
-If you enable caching, the [uv cache](https://docs.astral.sh/uv/concepts/cache/) will be cached to
+If you enable caching, the [uv cache](https://docs.astral.sh/uv/concepts/cache/) will be uploaded to
-the GitHub Actions Cache. This can speed up runs that reuse the cache by several minutes.
+the GitHub Actions cache. This can speed up runs that reuse the cache by several minutes.
 
 > [!TIP]
 >
@@ -119,9 +121,9 @@ use it in subsequent steps. For example, to use the cache in the above case:
 
 #### Cache dependency glob
 
-If you want to control when the cache is invalidated, specify a glob pattern with the
+If you want to control when the GitHub Actions cache is invalidated, specify a glob pattern with the
-`cache-dependency-glob` input. The cache will be invalidated if any file matching the glob pattern
+`cache-dependency-glob` input. The GitHub Actions cache will be invalidated if any file matching the glob pattern
-changes. If you use relative paths, the glob matches files relative to the repository root.
+changes. If you use relative paths, they are relative to the repository root.
 
 > [!NOTE]
 >
@@ -181,8 +183,8 @@ By default, the uv cache is pruned after every run, removing pre-built wheels, b
 wheels that were built from source. On GitHub-hosted runners, it's typically faster to omit those
 pre-built wheels from the cache (and instead re-download them from the registry on each run).
 However, on self-hosted or local runners, preserving the cache may be more efficient. See
-the[documentation](https://docs.astral.sh/uv/concepts/cache/#caching-in-continuous-integration) for
+the [documentation](https://docs.astral.sh/uv/concepts/cache/#caching-in-continuous-integration) for
-more.
+more information.
 
 If you want to persist the entire cache across runs, disable cache pruning with the `prune-cache`
 input.
@@ -195,6 +197,19 @@ input.
     prune-cache: false
 ```
 
+### Ignore nothing to cache
+
+By default, the action will fail if there is nothing to cache (the uv cache directory does not exist).
+If you want to ignore this, set the `ignore-nothing-to-cache` input to `true`.
+
+```yaml
+- name: Ignore nothing to cache
+  uses: astral-sh/setup-uv@v3
+  with:
+    enable-cache: true
+    ignore-nothing-to-cache: true
+```
+
 ### GitHub authentication token
 
 This action uses the GitHub API to fetch the uv release artifacts. To avoid hitting the GitHub API

action.yml

@@ -31,7 +31,10 @@ inputs:
     default: ""
   prune-cache:
     description: "Prune cache before saving."
-    default: true
+    default: "true"
+  ignore-nothing-to-cache:
+    description: "Ignore when nothing is found to cache."
+    default: "false"
   tool-dir:
     description: "Custom path to set UV_TOOL_DIR to."
     required: false

dist/save-cache/index.js

@@ -82336,7 +82336,7 @@ function computeKeys(version) {
             core.info(`Searching files using cache dependency glob: ${inputs_1.cacheDependencyGlob.split("\n").join(",")}`);
             cacheDependencyPathHash += yield (0, hash_files_1.hashFiles)(inputs_1.cacheDependencyGlob, true);
             if (cacheDependencyPathHash === "-") {
-                throw new Error(`No file in ${process.cwd()} matched to [${inputs_1.cacheDependencyGlob.split("\n").join(",")}], make sure you have checked out the target repository`);
+                throw new Error(`No file matched to [${inputs_1.cacheDependencyGlob.split("\n").join(",")}], make sure you have checked out the target repository`);
             }
         }
         else {
@@ -82510,6 +82510,7 @@ exports.run = run;
 const cache = __importStar(__nccwpck_require__(5116));
 const core = __importStar(__nccwpck_require__(7484));
 const exec = __importStar(__nccwpck_require__(5236));
+const fs = __importStar(__nccwpck_require__(3024));
 const restore_cache_1 = __nccwpck_require__(5391);
 const inputs_1 = __nccwpck_require__(9612);
 function run() {
@@ -82517,13 +82518,18 @@ function run() {
         try {
             if (inputs_1.enableCache) {
                 yield saveCache();
+                // node will stay alive if any promises are not resolved,
+                // which is a possibility if HTTP requests are dangling
+                // due to retries or timeouts. We know that if we got here
+                // that all promises that we care about have successfully
+                // resolved, so simply exit with success.
+                process.exit(0);
             }
         }
         catch (error) {
             const err = error;
             core.setFailed(err.message);
         }
-        process.exit(0);
     });
 }
 function saveCache() {
@@ -82542,8 +82548,23 @@ function saveCache() {
             yield pruneCache();
         }
         core.info(`Saving cache path: ${inputs_1.cacheLocalPath}`);
-        yield cache.saveCache([inputs_1.cacheLocalPath], cacheKey);
+        if (!fs.existsSync(inputs_1.cacheLocalPath) && !inputs_1.ignoreNothingToCache) {
-        core.info(`cache saved with the key: ${cacheKey}`);
+            throw new Error(`Cache path ${inputs_1.cacheLocalPath} does not exist on disk. This likely indicates that there are no dependencies to cache. Consider disabling the cache input if it is not needed.`);
+        }
+        try {
+            yield cache.saveCache([inputs_1.cacheLocalPath], cacheKey);
+            core.info(`cache saved with the key: ${cacheKey}`);
+        }
+        catch (e) {
+            if (e instanceof Error &&
+                e.message ===
+                    "Path Validation Error: Path(s) specified in the action for caching do(es) not exist, hence no cache is being saved.") {
+                core.info("No cacheable paths were found. Ignoring because ignore-nothing-to-save is enabled.");
+            }
+            else {
+                throw e;
+            }
+        }
     });
 }
 function pruneCache() {
@@ -82593,7 +82614,7 @@ var __importDefault = (this && this.__importDefault) || function (mod) {
     return (mod && mod.__esModule) ? mod : { "default": mod };
 };
 Object.defineProperty(exports, "__esModule", ({ value: true }));
-exports.githubToken = exports.toolDir = exports.toolBinDir = exports.pruneCache = exports.cacheDependencyGlob = exports.cacheLocalPath = exports.cacheSuffix = exports.enableCache = exports.checkSum = exports.version = void 0;
+exports.githubToken = exports.toolDir = exports.toolBinDir = exports.ignoreNothingToCache = exports.pruneCache = exports.cacheDependencyGlob = exports.cacheLocalPath = exports.cacheSuffix = exports.enableCache = exports.checkSum = exports.version = void 0;
 const core = __importStar(__nccwpck_require__(7484));
 const node_path_1 = __importDefault(__nccwpck_require__(6760));
 exports.version = core.getInput("version");
@@ -82603,6 +82624,7 @@ exports.cacheSuffix = core.getInput("cache-suffix") || "";
 exports.cacheLocalPath = getCacheLocalPath();
 exports.cacheDependencyGlob = core.getInput("cache-dependency-glob");
 exports.pruneCache = core.getInput("prune-cache") === "true";
+exports.ignoreNothingToCache = core.getInput("ignore-nothing-to-cache") === "true";
 exports.toolBinDir = getToolBinDir();
 exports.toolDir = getToolDir();
 exports.githubToken = core.getInput("github-token");

dist/setup/index.js

@@ -87419,7 +87419,7 @@ function computeKeys(version) {
             core.info(`Searching files using cache dependency glob: ${inputs_1.cacheDependencyGlob.split("\n").join(",")}`);
             cacheDependencyPathHash += yield (0, hash_files_1.hashFiles)(inputs_1.cacheDependencyGlob, true);
             if (cacheDependencyPathHash === "-") {
-                throw new Error(`No file in ${process.cwd()} matched to [${inputs_1.cacheDependencyGlob.split("\n").join(",")}], make sure you have checked out the target repository`);
+                throw new Error(`No file matched to [${inputs_1.cacheDependencyGlob.split("\n").join(",")}], make sure you have checked out the target repository`);
             }
         }
         else {
@@ -90268,7 +90268,7 @@ var __importDefault = (this && this.__importDefault) || function (mod) {
     return (mod && mod.__esModule) ? mod : { "default": mod };
 };
 Object.defineProperty(exports, "__esModule", ({ value: true }));
-exports.githubToken = exports.toolDir = exports.toolBinDir = exports.pruneCache = exports.cacheDependencyGlob = exports.cacheLocalPath = exports.cacheSuffix = exports.enableCache = exports.checkSum = exports.version = void 0;
+exports.githubToken = exports.toolDir = exports.toolBinDir = exports.ignoreNothingToCache = exports.pruneCache = exports.cacheDependencyGlob = exports.cacheLocalPath = exports.cacheSuffix = exports.enableCache = exports.checkSum = exports.version = void 0;
 const core = __importStar(__nccwpck_require__(7484));
 const node_path_1 = __importDefault(__nccwpck_require__(6760));
 exports.version = core.getInput("version");
@@ -90278,6 +90278,7 @@ exports.cacheSuffix = core.getInput("cache-suffix") || "";
 exports.cacheLocalPath = getCacheLocalPath();
 exports.cacheDependencyGlob = core.getInput("cache-dependency-glob");
 exports.pruneCache = core.getInput("prune-cache") === "true";
+exports.ignoreNothingToCache = core.getInput("ignore-nothing-to-cache") === "true";
 exports.toolBinDir = getToolBinDir();
 exports.toolDir = getToolDir();
 exports.githubToken = core.getInput("github-token");

src/cache/restore-cache.ts

@@ -42,7 +42,7 @@ async function computeKeys(version: string): Promise<string> {
     cacheDependencyPathHash += await hashFiles(cacheDependencyGlob, true);
     if (cacheDependencyPathHash === "-") {
       throw new Error(
-        `No file in ${process.cwd()} matched to [${cacheDependencyGlob.split("\n").join(",")}], make sure you have checked out the target repository`,
+        `No file matched to [${cacheDependencyGlob.split("\n").join(",")}], make sure you have checked out the target repository`,
       );
     }
   } else {

src/save-cache.ts

@@ -1,6 +1,7 @@
 import * as cache from "@actions/cache";
 import * as core from "@actions/core";
 import * as exec from "@actions/exec";
+import * as fs from "node:fs";
 import {
   STATE_CACHE_MATCHED_KEY,
   STATE_CACHE_KEY,
@@ -8,6 +9,7 @@ import {
 import {
   cacheLocalPath,
   enableCache,
+  ignoreNothingToCache,
   pruneCache as shouldPruneCache,
 } from "./utils/inputs";
 
@@ -15,12 +17,17 @@ export async function run(): Promise<void> {
   try {
     if (enableCache) {
       await saveCache();
+      // node will stay alive if any promises are not resolved,
+      // which is a possibility if HTTP requests are dangling
+      // due to retries or timeouts. We know that if we got here
+      // that all promises that we care about have successfully
+      // resolved, so simply exit with success.
+      process.exit(0);
     }
   } catch (error) {
     const err = error as Error;
     core.setFailed(err.message);
   }
-  process.exit(0);
 }
 
 async function saveCache(): Promise<void> {
@@ -41,9 +48,27 @@ async function saveCache(): Promise<void> {
   }
 
   core.info(`Saving cache path: ${cacheLocalPath}`);
-  await cache.saveCache([cacheLocalPath], cacheKey);
+  if (!fs.existsSync(cacheLocalPath) && !ignoreNothingToCache) {
-
+    throw new Error(
-  core.info(`cache saved with the key: ${cacheKey}`);
+      `Cache path ${cacheLocalPath} does not exist on disk. This likely indicates that there are no dependencies to cache. Consider disabling the cache input if it is not needed.`,
+    );
+  }
+  try {
+    await cache.saveCache([cacheLocalPath], cacheKey);
+    core.info(`cache saved with the key: ${cacheKey}`);
+  } catch (e) {
+    if (
+      e instanceof Error &&
+      e.message ===
+        "Path Validation Error: Path(s) specified in the action for caching do(es) not exist, hence no cache is being saved."
+    ) {
+      core.info(
+        "No cacheable paths were found. Ignoring because ignore-nothing-to-save is enabled.",
+      );
+    } else {
+      throw e;
+    }
+  }
 }
 
 async function pruneCache(): Promise<void> {

src/utils/inputs.ts

@@ -8,6 +8,8 @@ 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";
+export const ignoreNothingToCache =
+  core.getInput("ignore-nothing-to-cache") === "true";
 export const toolBinDir = getToolBinDir();
 export const toolDir = getToolDir();
 export const githubToken = core.getInput("github-token");