Port macOS tests from CircleCI got GHA

.github/unittest.sh

@@ -0,0 +1,84 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+echo '::group::Prepare conda'
+CONDA_PATH=$(which conda)
+eval "$(${CONDA_PATH} shell.bash hook)"
+# The `setuptools` package installed through `conda` includes a patch that errors if something is installed
+# through `setuptools` while the `CONDA_BUILD` environment variable is set.
+# https://github.com/AnacondaRecipes/setuptools-feedstock/blob/f5d8d256810ce28fc0cf34170bc34e06d3754041/recipe/patches/0002-disable-downloads-inside-conda-build.patch
+# (Although we are not using the `-c conda-forge` channel, the patch is equivalent but not public for
+# `setuptools` from the `-c defaults` channel)
+# Since we aren't using `conda build` here, we unset it to avoid installation problems later
+# TODO: investigate where `CONDA_BUILD` is set and maybe fix unset it there
+unset CONDA_BUILD
+echo '::endgroup::'
+
+echo '::group::Set PyTorch conda channel'
+# TODO: Can we maybe have this as environment variable in the job template? For example, `IS_RELEASE`.
+if [[ (${GITHUB_EVENT_NAME} = 'pull_request' && (${GITHUB_BASE_REF} = 'release'*)) || (${GITHUB_REF} = 'refs/heads/release'*) ]]; then
+  POSTFIX=test
+else
+  POSTFIX=nightly
+fi
+PYTORCH_CHANNEL=pytorch-"${POSTFIX}"
+echo "${PYTORCH_CHANNEL}"
+echo '::endgroup::'
+
+echo '::group::Set PyTorch GPU mutex'
+case $GPU_ARCH_TYPE in
+  cpu)
+    PYTORCH_MUTEX=cpuonly
+    ;;
+  cuda)
+    PYTORCH_MUTEX="pytorch-cuda=${GPU_ARCH_VERSION}"
+    ;;
+  *)
+    echo "Unknown GPU_ARCH_TYPE=${GPU_ARCH_TYPE}"
+    exit 1
+    ;;
+esac
+echo "${PYTORCH_MUTEX}"
+echo '::endgroup::'
+
+echo '::group::Create build environment'
+conda create \
+  --name ci \
+  --quiet --yes \
+  python="${PYTHON_VERSION}" pip \
+  setuptools ninja \
+  libpng jpeg \
+  Pillow numpy requests
+conda activate ci
+pip install 'av<10'
+echo '::endgroup::'
+
+echo '::group::Install PyTorch'
+conda install \
+  --quiet --yes \
+  -c "${PYTORCH_CHANNEL}" \
+  -c nvidia \
+  pytorch \
+  "${PYTORCH_MUTEX}"
+
+if [[ $GPU_ARCH_TYPE = 'cuda' ]]; then
+  python3 -c "import torch; exit(not torch.cuda.is_available())"
+fi
+echo '::endgroup::'
+
+echo '::group::Install TorchVision'
+python setup.py develop
+echo '::endgroup::'
+
+echo '::group::Collect PyTorch environment information'
+python -m torch.utils.collect_env
+echo '::endgroup::'
+
+echo '::group::Install testing utilities'
+pip install --progress-bar=off pytest pytest-mock pytest-cov
+echo '::endgroup::'
+
+echo '::group::Run tests'
+pytest --durations=25
+echo '::endgroup::'

.github/workflows/test-macos.yml

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+name: Unit-tests on macOS
+
+on:
+  pull_request:
+  push:
+    branches:
+      - nightly
+      - main
+      - release/*
+  workflow_dispatch:
+
+jobs:
+  tests:
+    strategy:
+      matrix:
+        python-version:
+          - "3.8"
+          - "3.9"
+          - "3.10"
+        runner: ["macos-12"]
+        include:
+          - python-version: "3.8"
+            runner: macos-m1-12
+      fail-fast: false
+    uses: pytorch/test-infra/.github/workflows/macos_job.yml@main
+    with:
+      repository: pytorch/vision
+      timeout: 120
+      runner: ${{ matrix.runner }}
+      script: |
+        export PYTHON_VERSION=${{ matrix.python-version }}
+        export GPU_ARCH_TYPE=cpu
+
+        ./.github/unittest.sh