RUNNER_OS should return macOS instead of darwin and wrong RUNNER_ARCH on MacOS M1

[x-yurii-uvarov]

Bug report info

act --bug-report                                    
act version:            0.2.34
GOOS:                   darwin
GOARCH:                 amd64
NumCPU:                 8
Docker host:            DOCKER_HOST environment variable is unset/empty.
Sockets found:
	/var/run/docker.sock
	/Users/yuriiuvarov/.docker/run/docker.sock
Config files:           
	/Users/yuriiuvarov/.actrc:
		-P ubuntu-latest=catthehacker/ubuntu:act-latest
		-P ubuntu-22.04=catthehacker/ubuntu:act-22.04
		-P ubuntu-20.04=catthehacker/ubuntu:act-20.04
		-P ubuntu-18.04=catthehacker/ubuntu:act-18.04
	.actrc:
		-P ubuntu-latest=catthehacker/ubuntu:act-latest
		-P ubuntu-22.04=catthehacker/ubuntu:act-22.04
		-P ubuntu-20.04=catthehacker/ubuntu:act-20.04
		-P ubuntu-18.04=catthehacker/ubuntu:act-18.04
Build info:
	Go version:            go1.19.3
	Module path:           command-line-arguments
	Main version:          
	Main path:             
	Main checksum:         
	Build settings:
		-compiler:            gc
		-ldflags:             -X main.version=0.2.34
		CGO_ENABLED:          1
		CGO_CFLAGS:           
		CGO_CPPFLAGS:         
		CGO_CXXFLAGS:         
		CGO_LDFLAGS:          
		GOARCH:               amd64
		GOOS:                 darwin
		GOAMD64:              v1
Docker Engine:
	Engine version:        20.10.21
	Engine runtime:        runc
	Cgroup version:        2
	Cgroup driver:         cgroupfs
	Storage driver:        overlay2
	Registry URI:          https://index.docker.io/v1/
	OS:                    Docker Desktop
	OS type:               linux
	OS version:            
	OS arch:               aarch64
	OS kernel:             5.15.49-linuxkit
	OS CPU:                4
	OS memory:             3933 MB
	Security options:
		name=seccomp,profile=default
		name=cgroupns

Command used with act

act -j build --platform macos-latest=-self-hosted

Describe issue

Some Github actions depend on the RUNNER_OS and expect one of the defined values according to the https://docs.github.com/en/actions/learn-github-actions/environment-variables#default-environment-variables.

The operating system of the runner executing the job. Possible values are Linux, Windows, or macOS

For example, flutter-action uses RUNNER_OS to build a link to the flutter binary.

expected result: macOS,
actual result: darwin

Also, RUNNER_ARCH should be arm64(or x64 using rosetta at least) but it provides amd64, which is definitely wrong.

Link to GitHub repository

No response

Workflow content

name: Linter & Tests

on:
  push:
    branches: [ main, redesign-master ]
  pull_request:
    branches: [ main, redesign-master ]

jobs:
  build:
    runs-on: macos-latest
    env:
      REPO_DIR: ${{ github.workspace }}
    steps:
      - uses: actions/checkout@v3
      - name: 'Test os'
        run: echo $RUNNER_OS
      - name: 'Set Flutter 3.3.9'
        uses: subosito/flutter-action@v2
        with:
          architecture: arm64
          flutter-version: 3.3.9

Relevant log output

This exceeds the GitHub character limit, please find it here:
https://drive.google.com/file/d/1UYD4cZqcdBm2jMyOISvDMpJ6XJ44LGZq/view?usp=sharing

Additional information

uname -a
Darwin Yuriis-MacBook-Pro.local 21.6.0 Darwin Kernel Version 21.6.0: Mon Aug 22 20:20:05 PDT 2022; root:xnu-8020.140.49~2/RELEASE_ARM64_T8101 arm64

[ChristopherHX]

@x-yurii-uvarov Could you please check if the arm64 version of act https://github.com/nektos/act/releases/download/v0.2.34/act_Darwin_arm64.tar.gz has the correct RUNNER_ARCH ?

You are right, the RUNNER_OS needs a remapping for macOS.

[ChristopherHX]

FYI Possible values for RUNNER_OS of act are also freebsd, openbsd, plan9, dragonfly, solaris and android.

If you run RUNNER_OS=macOS act ... you have the correct RUNNER_OS without a patch

[x-yurii-uvarov]

I have uninstalled the brew version of the act and tried yours, and RUNNER_ARCH changed from amd64 to arm64.
Also, RUNNER_OS=macOS act ... helped to change RUNNER_OS, and I can use it as a workaround for now.

Thank you @ChristopherHX! Both of your suggestions work!