OSX container name format incorrect

[v0l]

Description

On MacOS container names are in the incorrect format, containing a - instead of an _

<project>_<service>_<index>_<slug>

Steps to reproduce the issue:

1. docker compose up (On OSX)
2. docker compose up (On Windows)

Describe the results you received:
Containers on OSX contain - separator.
Containers on Windows contain _ separator.

Describe the results you expected:
Name format should be the same for all platforms.

Additional information you deem important (e.g. issue happens only occasionally):

Output of docker compose version:

Windows: Docker Compose version v2.0.0-rc.3
OSX: Docker Compose version v2.0.0

Output of docker info:

Windows:

Client:
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Build with BuildKit (Docker Inc., v0.6.1-docker)
  compose: Docker Compose (Docker Inc., v2.0.0-rc.3)
  scan: Docker Scan (Docker Inc., v0.8.0)

Server:
 Containers: 19
  Running: 15
  Paused: 0
  Stopped: 4
 Images: 27
 Server Version: 20.10.8
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 1
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: io.containerd.runc.v2 io.containerd.runtime.v1.linux runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: e25210fe30a0a703442421b0f60afac609f950a3
 runc version: v1.0.1-0-g4144b63
 init version: de40ad0
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 5.10.16.3-microsoft-standard-WSL2
 Operating System: Docker Desktop
 OSType: linux
 Architecture: x86_64
 CPUs: 12
 Total Memory: 25GiB
 Name: docker-desktop
 ID: KZWF:XGDX:X7BD:EMTZ:57OD:3URA:XRCJ:WFMD:3POD:EEXV:5VF2:VVEJ
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false

OSX:

Client:
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Build with BuildKit (Docker Inc., v0.6.3)
  compose: Docker Compose (Docker Inc., v2.0.0)
  scan: Docker Scan (Docker Inc., v0.8.0)

Server:
 Containers: 16
  Running: 12
  Paused: 0
  Stopped: 4
 Images: 9
 Server Version: 20.10.8
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 1
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: io.containerd.runc.v2 io.containerd.runtime.v1.linux runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: e25210fe30a0a703442421b0f60afac609f950a3
 runc version: v1.0.1-0-g4144b63
 init version: de40ad0
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 5.10.47-linuxkit
 Operating System: Docker Desktop
 OSType: linux
 Architecture: x86_64
 CPUs: 4
 Total Memory: 1.939GiB
 Name: docker-desktop
 ID: H5LG:2GJP:7BAS:MXYC:QNCQ:X6KA:SNGD:WKMD:UUH7:OE3L:TWMK:NP4W
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 HTTP Proxy: http.docker.internal:3128
 HTTPS Proxy: http.docker.internal:3128
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false

Additional environment details:
Windows OS: 10
Mac OSX: Big Sur

[mat007]

You’re not using the same compose version on both platforms. 😁

This behaviour is intentional, see #8655
You can get underscores by using --compatibility.

[v0l]

You’re not using the same compose version on both platforms

They are both on ComposeV2, maybe its worth documenting somewhere that the name format is changing? Like here: https://docs.docker.com/compose/cli-command/

[v0l]

I updated my windows install to to V2.0.0 and its containing a - now.

[mat007]

They are both on ComposeV2, maybe its worth documenting somewhere that the name format is changing? Like here: https://docs.docker.com/compose/cli-command/

That is a good suggestion. We have a list of changes from V1 to V2 like that one to publish, we really need to do it.
Thanks for the nudge!