From c933f3c50ea2d98bc61f4112402f951e73d26ed8 Mon Sep 17 00:00:00 2001
From: dhvcc <1337kwiz@gmail.com>
Date: Sun, 3 Apr 2022 02:33:19 +0300
Subject: [PATCH] Added cache-hit output

---
 __tests__/cache-restore.test.ts              | 31 ++++++++++++++++++++
 action.yml                                   |  2 ++
 src/cache-distributions/cache-distributor.ts |  8 +++++
 src/utils.ts                                 |  9 ++++++
 4 files changed, 50 insertions(+)

diff --git a/__tests__/cache-restore.test.ts b/__tests__/cache-restore.test.ts
index 7b4dcf02..55cc571b 100644
--- a/__tests__/cache-restore.test.ts
+++ b/__tests__/cache-restore.test.ts
@@ -191,6 +191,37 @@ virtualenvs.path = "{cache-dir}/virtualenvs"  # /Users/patrick/Library/Caches/py
     );
   });
 
+  describe('Check if handleMatchResult', () => {
+    it.each([
+      ['pip', '3.8.12', 'requirements.txt', 'someKey', true],
+      ['pipenv', '3.9.1', 'requirements.txt', 'someKey', true],
+      ['poetry', '3.8.12', 'requirements.txt', 'someKey', true],
+      ['pip', '3.9.2', 'requirements.txt', undefined, false],
+      ['pipenv', '3.8.12', 'requirements.txt', undefined, false],
+      ['poetry', '3.9.12', 'requirements.txt', undefined, false]
+    ])(
+      'sets correct outputs',
+      async (
+        packageManager,
+        pythonVersion,
+        dependencyFile,
+        matchedKey,
+        expectedOutputValue
+      ) => {
+        const cacheDistributor = getCacheDistributor(
+          packageManager,
+          pythonVersion,
+          dependencyFile
+        );
+        cacheDistributor.handleMatchResult(matchedKey);
+        expect(setOutputSpy).toHaveBeenCalledWith(
+          'cache-hit',
+          expectedOutputValue
+        );
+      }
+    );
+  });
+
   afterEach(() => {
     jest.resetAllMocks();
     jest.clearAllMocks();
diff --git a/action.yml b/action.yml
index bd9ee686..bda521dd 100644
--- a/action.yml
+++ b/action.yml
@@ -19,6 +19,8 @@ inputs:
 outputs:
   python-version:
     description: "The installed python version. Useful when given a version range as input."
+  cache-hit:
+    description: 'A boolean value to indicate a cache entry was found'
 runs:
   using: 'node16'
   main: 'dist/setup/index.js'
diff --git a/src/cache-distributions/cache-distributor.ts b/src/cache-distributions/cache-distributor.ts
index ef0be0ef..3b30076c 100644
--- a/src/cache-distributions/cache-distributor.ts
+++ b/src/cache-distributions/cache-distributor.ts
@@ -1,5 +1,6 @@
 import * as cache from '@actions/cache';
 import * as core from '@actions/core';
+import {PromiseReturnType} from '../utils';
 
 export enum State {
   STATE_CACHE_PRIMARY_KEY = 'cache-primary-key',
@@ -41,12 +42,19 @@ abstract class CacheDistributor {
       restoreKey
     );
 
+    this.handleMatchResult(matchedKey);
+  }
+
+  public handleMatchResult(
+    matchedKey: PromiseReturnType<typeof cache.restoreCache>
+  ) {
     if (matchedKey) {
       core.saveState(State.CACHE_MATCHED_KEY, matchedKey);
       core.info(`Cache restored from key: ${matchedKey}`);
     } else {
       core.info(`${this.packageManager} cache is not found`);
     }
+    core.setOutput('cache-hit', Boolean(matchedKey));
   }
 }
 
diff --git a/src/utils.ts b/src/utils.ts
index eb3a1ba6..f0dca7e1 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -119,3 +119,12 @@ export function isCacheFeatureAvailable(): boolean {
 
   return true;
 }
+
+// Awaited (typescript 4.5+) polyfill. Not ideal, so use with care
+export type AwaitedPolyfill<T> = T extends PromiseLike<infer U>
+  ? AwaitedPolyfill<U>
+  : T;
+// Extract return type from promise
+export type PromiseReturnType<
+  T extends (...args: any) => any
+> = AwaitedPolyfill<ReturnType<T>>;