Cache Gradle wrapper distribution separately from the dependency cache (#1098)

The Gradle wrapper distribution (~/.gradle/wrapper) only depends on
gradle-wrapper.properties, which changes rarely, but it was previously
cached in the same entry as ~/.gradle/caches, keyed on volatile
**/*.gradle* files with no restoreKeys (issue #269). Every dependency
change therefore re-downloaded the wrapper.

Move ~/.gradle/wrapper into a dedicated `gradle-wrapper` additional
cache keyed only on **/gradle-wrapper.properties, reusing the
additionalCaches infrastructure introduced for the Maven wrapper fix.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

__tests__/cache.test.ts

@@ -316,6 +316,43 @@ describe('dependency cache', () => {
         expect(spyWarning).not.toHaveBeenCalled();
         expect(spyInfo).toHaveBeenCalledWith('gradle cache is not found');
       });
+      it('restores the gradle wrapper distribution cache independently of the main cache', async () => {
+        createFile(join(workspace, 'build.gradle'));
+
+        await restore('gradle', '');
+        // Main dependency cache no longer carries the wrapper path.
+        expect(spyCacheRestore).toHaveBeenCalledWith(
+          [join(os.homedir(), '.gradle', 'caches')],
+          expect.any(String)
+        );
+        // Wrapper distribution is restored on its own, keyed only on the
+        // wrapper properties file.
+        expect(spyCacheRestore).toHaveBeenCalledWith(
+          [join(os.homedir(), '.gradle', 'wrapper')],
+          expect.stringContaining('setup-java-')
+        );
+        expect(spyGlobHashFiles).toHaveBeenCalledWith(
+          '**/gradle-wrapper.properties'
+        );
+      });
+      it('skips the gradle wrapper cache when no wrapper properties exist', async () => {
+        createFile(join(workspace, 'build.gradle'));
+        spyGlobHashFiles.mockImplementation((pattern: string) =>
+          Promise.resolve(
+            pattern === '**/gradle-wrapper.properties' ? '' : 'hash-stub'
+          )
+        );
+
+        await restore('gradle', '');
+        // Only the main dependency cache is restored; the wrapper cache path is
+        // never touched because the project does not use the gradle wrapper.
+        expect(spyCacheRestore).toHaveBeenCalledTimes(1);
+        expect(spyCacheRestore).toHaveBeenCalledWith(
+          [join(os.homedir(), '.gradle', 'caches')],
+          expect.any(String)
+        );
+        expect(spyWarning).not.toHaveBeenCalled();
+      });
     });
     describe('for sbt', () => {
       it('throws error if no build.sbt found', async () => {
@@ -587,6 +624,50 @@ describe('dependency cache', () => {
           expect.stringMatching(/^Cache saved with the key:.*/)
         );
       });
+      it('saves the gradle wrapper distribution cache under its own key', async () => {
+        createFile(join(workspace, 'build.gradle'));
+        (core.getState as jest.Mock<any>).mockImplementation((name: any) => {
+          switch (name) {
+            case 'cache-primary-key':
+              return 'setup-java-cache-primary-key';
+            case 'cache-matched-key':
+              return 'setup-java-cache-matched-key';
+            case 'cache-primary-key-gradle-wrapper':
+              return 'setup-java-gradle-wrapper-key';
+            default:
+              return '';
+          }
+        });
+
+        await save('gradle');
+        expect(spyCacheSave).toHaveBeenCalledWith(
+          [join(os.homedir(), '.gradle', 'wrapper')],
+          'setup-java-gradle-wrapper-key'
+        );
+        expect(spyWarning).not.toHaveBeenCalled();
+      });
+      it('does not save the gradle wrapper cache on an exact wrapper hit', async () => {
+        createFile(join(workspace, 'build.gradle'));
+        (core.getState as jest.Mock<any>).mockImplementation((name: any) => {
+          switch (name) {
+            case 'cache-primary-key':
+              return 'setup-java-cache-primary-key';
+            case 'cache-matched-key':
+              return 'setup-java-cache-matched-key';
+            case 'cache-primary-key-gradle-wrapper':
+            case 'cache-matched-key-gradle-wrapper':
+              return 'setup-java-gradle-wrapper-key';
+            default:
+              return '';
+          }
+        });
+
+        await save('gradle');
+        expect(spyCacheSave).not.toHaveBeenCalledWith(
+          [join(os.homedir(), '.gradle', 'wrapper')],
+          expect.any(String)
+        );
+      });
     });
     describe('for sbt', () => {
       it('uploads cache even if no build.sbt found', async () => {

dist/cleanup/index.js

@@ -99687,10 +99687,7 @@ const supportedPackageManager = [
     },
     {
         id: 'gradle',
-        path: [
+        path: [(0,external_path_.join)(external_os_default().homedir(), '.gradle', 'caches')],
-            (0,external_path_.join)(external_os_default().homedir(), '.gradle', 'caches'),
-            (0,external_path_.join)(external_os_default().homedir(), '.gradle', 'wrapper')
-        ],
         // https://github.com/actions/cache/blob/0638051e9af2c23d10bb70fa9beffcad6cff9ce3/examples.md#java---gradle
         pattern: [
             '**/*.gradle*',
@@ -99699,6 +99696,17 @@ const supportedPackageManager = [
             'buildSrc/**/Dependencies.kt',
             'gradle/*.versions.toml',
             '**/versions.properties'
+        ],
+        // The Gradle wrapper distribution only depends on the wrapper properties,
+        // which change very rarely, so it is cached separately from the Gradle
+        // caches. This keeps it available across the frequent *.gradle* changes
+        // that rotate the main cache key. See issue #1095.
+        additionalCaches: [
+            {
+                name: 'gradle-wrapper',
+                path: [(0,external_path_.join)(external_os_default().homedir(), '.gradle', 'wrapper')],
+                pattern: ['**/gradle-wrapper.properties']
+            }
         ]
     },
     {

dist/setup/index.js

@@ -130909,10 +130909,7 @@ const supportedPackageManager = [
     },
     {
         id: 'gradle',
-        path: [
+        path: [(0,external_path_.join)(external_os_default().homedir(), '.gradle', 'caches')],
-            (0,external_path_.join)(external_os_default().homedir(), '.gradle', 'caches'),
-            (0,external_path_.join)(external_os_default().homedir(), '.gradle', 'wrapper')
-        ],
         // https://github.com/actions/cache/blob/0638051e9af2c23d10bb70fa9beffcad6cff9ce3/examples.md#java---gradle
         pattern: [
             '**/*.gradle*',
@@ -130921,6 +130918,17 @@ const supportedPackageManager = [
             'buildSrc/**/Dependencies.kt',
             'gradle/*.versions.toml',
             '**/versions.properties'
+        ],
+        // The Gradle wrapper distribution only depends on the wrapper properties,
+        // which change very rarely, so it is cached separately from the Gradle
+        // caches. This keeps it available across the frequent *.gradle* changes
+        // that rotate the main cache key. See issue #1095.
+        additionalCaches: [
+            {
+                name: 'gradle-wrapper',
+                path: [(0,external_path_.join)(external_os_default().homedir(), '.gradle', 'wrapper')],
+                pattern: ['**/gradle-wrapper.properties']
+            }
         ]
     },
     {

src/cache.ts

@@ -72,10 +72,7 @@ const supportedPackageManager: PackageManager[] = [
   },
   {
     id: 'gradle',
-    path: [
+    path: [join(os.homedir(), '.gradle', 'caches')],
-      join(os.homedir(), '.gradle', 'caches'),
-      join(os.homedir(), '.gradle', 'wrapper')
-    ],
     // https://github.com/actions/cache/blob/0638051e9af2c23d10bb70fa9beffcad6cff9ce3/examples.md#java---gradle
     pattern: [
       '**/*.gradle*',
@@ -84,6 +81,17 @@ const supportedPackageManager: PackageManager[] = [
       'buildSrc/**/Dependencies.kt',
       'gradle/*.versions.toml',
       '**/versions.properties'
+    ],
+    // The Gradle wrapper distribution only depends on the wrapper properties,
+    // which change very rarely, so it is cached separately from the Gradle
+    // caches. This keeps it available across the frequent *.gradle* changes
+    // that rotate the main cache key. See issue #1095.
+    additionalCaches: [
+      {
+        name: 'gradle-wrapper',
+        path: [join(os.homedir(), '.gradle', 'wrapper')],
+        pattern: ['**/gradle-wrapper.properties']
+      }
     ]
   },
   {