don't save caches for PRs (#14389)

.github/actions/cache/action.yml

@@ -0,0 +1,30 @@
+name: Cache
+description: Wraps actions/cache to disable save for PRs
+inputs:
+  path:
+    description: 'A list of files, directories, and wildcard patterns to cache and restore'
+    required: true
+  key:
+    description: 'An explicit key for restoring and saving the cache'
+    required: true
+outputs:
+  cache-hit:
+    description: 'A boolean value to indicate an exact match was found for the primary key'
+    value: ${{ steps.restore-only.outputs.cache-hit || steps.restore-save.outputs.cache-hit }}
+runs:
+  using: "composite"
+  steps:
+    - name: Restore Cache (PR)
+      if: github.event_name == 'pull_request'
+      id: restore-only
+      uses: actions/cache/restore@v4
+      with:
+        path: ${{ inputs.path }}
+        key: ${{ inputs.key }}
+    - name: Restore and Save Cache
+      if: github.event_name != 'pull_request'
+      id: restore-save
+      uses: actions/cache@v4
+      with:
+        path: ${{ input.path }}
+        key: ${{ input.key }}

.github/actions/setup-tinygrad/action.yml

@@ -58,24 +58,18 @@ runs:
 
     - name: Cache Python packages
       id: restore-venv
-      uses: actions/cache@v4
+      uses: ./.github/actions/cache
       with:
         path: ${{ github.workspace }}/.venv
         key: venv-${{ runner.os }}-python-${{ steps.setup-python.outputs.python-version }}-${{ inputs.deps }}-${{ inputs.pydeps }}-${{ env.CACHE_VERSION }}
 
     # **** Caching downloads ****
 
-    - name: Cache downloads (Linux)
-      if: inputs.key != '' && runner.os == 'Linux'
-      uses: actions/cache@v4
+    - name: Cache downloads
+      if: inputs.key != ''
+      uses: ./.github/actions/cache
       with:
-        path: ~/.cache/tinygrad/downloads/
-        key: downloads-${{ github.job }}-${{ inputs.key }}-${{ env.CACHE_VERSION }}
-    - name: Cache downloads (macOS)
-      if: inputs.key != '' && runner.os == 'macOS'
-      uses: actions/cache@v4
-      with:
-        path: ~/Library/Caches/tinygrad/downloads/
+        path: ${{ runner.os == 'Linux' && '~/.cache/tinygrad/downloads/' || '~/Library/Caches/tinygrad/downloads/' }}
         key: downloads-${{ github.job }}-${{ inputs.key }}-${{ env.CACHE_VERSION }}
 
     # **** Python deps ****
@@ -184,7 +178,7 @@ runs:
 
     - name: Cache apt
       if: runner.os == 'Linux' && (inputs.opencl == 'true' || inputs.amd == 'true' || inputs.cuda == 'true' || inputs.webgpu == 'true' || inputs.llvm == 'true')
-      uses: actions/cache@v4
+      uses: ./.github/actions/cache
       with:
         path: /var/cache/apt/archives/
         key: ${{ runner.os }}-apt-${{ steps.apt-pkgs.outputs.hash }}-${{ env.CACHE_VERSION }}
@@ -242,7 +236,7 @@ runs:
     - name: Cache gpuocelot
       if: inputs.ocelot == 'true'
       id: cache-build
-      uses: actions/cache@v4
+      uses: ./.github/actions/cache
       env:
         cache-name: cache-gpuocelot-build-1
       with: