[BUG] Flaky behavior with double `!override` and extends

[MaksimZayats]

Description

Hi folks!

I'm not sure what is going on with this thing, but docker compose couldn't always parse the following structure.
This started to happen after one of the recent updates...

Steps To Reproduce

Create the following file structure:

min/
├── docker-compose.yaml
├── docker-compose.child1.yaml
├── docker-compose.child2.yaml
└── docker-compose.shared.yaml

docker-compose.yaml:

include:
  - docker-compose.child1.yaml
  - docker-compose.child2.yaml

docker-compose.child1.yaml:

include:
  - docker-compose.shared.yaml

docker-compose.child2.yaml:

include:
  - docker-compose.shared.yaml

docker-compose.shared.yaml:

services:
  dep:
    image: ubuntu

  dep2:
    image: ubuntu

  base:
    image: ubuntu
    depends_on:
      - dep

  base2:
    extends:
      service: base
    depends_on: !override
      - dep2

  shared:
    extends:
      service: base2
    depends_on: !override
      - dep

Run command:

for i in {1..100}; do output=$(docker compose config --services 2>&1 >/dev/null) && echo -n "✅" || { echo -e "\n❌ Failed at $i\n$output"; break; }; done

At some point, it will fail:

✅✅✅✅✅✅✅
❌ Failed at 8
services.base2 conflicts with imported resource

But in good scenario it will show the following:

> docker compose config --services

dep
base
dep2
base2
shared

Compose Version

Docker Compose version v2.40.3-desktop.1

Docker Environment

Client:
 Version:    28.5.1
 Context:    desktop-linux
 Debug Mode: false
 Plugins:
  ai: Docker AI Agent - Ask Gordon (Docker Inc.)
    Version:  v1.9.11
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-ai
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.29.1-desktop.1
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-buildx
  compose: Docker Compose (Docker Inc.)
    Version:  v2.40.3-desktop.1
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-compose
  debug: Get a shell into any image or container (Docker Inc.)
    Version:  0.0.45
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-debug
  desktop: Docker Desktop commands (Docker Inc.)
    Version:  v0.2.0
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-desktop
  extension: Manages Docker extensions (Docker Inc.)
    Version:  v0.2.31
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-extension
  init: Creates Docker-related starter files for your project (Docker Inc.)
    Version:  v1.4.0
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-init
  mcp: Docker MCP Plugin (Docker Inc.)
    Version:  v0.24.0
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-mcp
  model: Docker Model Runner (Docker Inc.)
    Version:  v0.1.46
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-model
  offload: Docker Offload (Docker Inc.)
    Version:  v0.5.1
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-offload
  sandbox: Docker Sandbox (Docker Inc.)
    Version:  v0.3.1
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-sandbox
  sbom: View the packaged-based Software Bill Of Materials (SBOM) for an image (Anchore Inc.)
    Version:  0.6.0
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-sbom
  scout: Docker Scout (Docker Inc.)
    Version:  v1.18.3
    Path:     /Users/maksim.zayats/.docker/cli-plugins/docker-scout

Server:
 Containers: 38
  Running: 0
  Paused: 0
  Stopped: 38
 Images: 118
 Server Version: 28.5.1
 Storage Driver: overlayfs
  driver-type: io.containerd.snapshotter.v1
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 2
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local splunk syslog
 CDI spec directories:
  /etc/cdi
  /var/run/cdi
 Discovered Devices:
  cdi: docker.com/gpu=webgpu
 Swarm: inactive
 Runtimes: io.containerd.runc.v2 runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 05044ec0a9a75232cad458027ca83437aae3f4da
 runc version: v1.2.5-0-g59923ef
 init version: de40ad0
 Security Options:
  seccomp
   Profile: builtin
  cgroupns
 Kernel Version: 6.10.14-linuxkit
 Operating System: Docker Desktop
 OSType: linux
 Architecture: aarch64
 CPUs: 14
 Total Memory: 29.33GiB
 Name: docker-desktop
 ID: 7f57a7cb-e395-4e74-bc38-bec10b44c5c8
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 HTTP Proxy: http.docker.internal:3128
 HTTPS Proxy: http.docker.internal:3128
 No Proxy: hubproxy.docker.internal
 Labels:
  com.docker.desktop.address=unix:///Users/maksim.zayats/Library/Containers/com.docker.docker/Data/docker-cli.sock
 Experimental: false
 Insecure Registries:
  hubproxy.docker.internal:5555
  ::1/128
  127.0.0.0/8
 Live Restore Enabled: false

Anything else?

No response

[ndeloof]

probably fixed by compose-spec/compose-go#833

[ndeloof]

Would you have a chance to give latest release candidate a try and confirm issue is fixed ?

[MaksimZayats]

Hi @ndeloof !
Unfortunately, it looks like the problem is still there :(

➜   for i in {1..100}; do output=$(../docker-compose-darwin-aarch64 config --services 2>&1 >/dev/null) && echo -n " ✅" || { echo -e "\n❌ Failed at $i\n$output"; break; }; done

✅✅✅✅✅
❌ Failed at 6
services.base2 conflicts with imported resourc

➜   ../docker-compose-darwin-aarch64 version
Docker Compose version v5.0.0-rc.2

➜   docker version
Client:
 Version:           29.0.1
 API version:       1.52
 Go version:        go1.25.4
 Git commit:        eedd969
 Built:             Fri Nov 14 16:16:57 2025
 OS/Arch:           darwin/arm64
 Context:           desktop-linux

Server: Docker Desktop 4.53.0 (211793)
 Engine:
  Version:          29.0.1
  API version:      1.52 (minimum version 1.44)
  Go version:       go1.25.4
  Git commit:       198b5e3
  Built:            Fri Nov 14 16:18:20 2025
  OS/Arch:          linux/arm64
  Experimental:     false
 containerd:
  Version:          v2.1.5
  GitCommit:        fcd43222d6b07379a4be9786bda52438f0dd16a1
 runc:
  Version:          1.3.3
  GitCommit:        v1.3.3-0-gd842d771
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

[MaksimZayats]

Hi @ndeloof ! Great news!

I just tested the latest 5.0.0 version, and it looks like the issue is not happening anymore! 💪

Thanks so much!