Failure Path Testing#

Verify the installer handles errors gracefully: no stale state, clear error messages, working retry/cancel.

Refs: #44|Closes

Failure Scenarios#

1. Network failure during image pull#

• Trigger: Disconnect network after mount but before bootc install
• Expected: fisherman emits fatal error with "network" category
• Verify: Done screen shows network error hint, retry button works

2. Invalid/unreachable image reference#

• Trigger: Set image to ghcr.io/nonexistent/repo:tag
• Expected: Podman/bootc fails to pull, fisherman exits non-zero
• Verify: Error hint mentions image or registry, log shows podman error

3. Disk too small#

• Trigger: Target a 2GB USB stick
• Expected: Partitioning fails (not enough space)
• Verify: Error shown before any destructive writes if possible

4. Disk busy/mounted#

• Trigger: Mount a partition on the target disk before installing
• Expected: fisherman detects busy disk and fails early
• Verify: Helpful error, no partial partition table

5. LUKS passphrase issues#

• Trigger: Empty passphrase or special characters
• Expected: cryptsetup handles gracefully
• Verify: No hang, clear error if passphrase rejected

6. fisherman binary missing/corrupt#

• Trigger: Delete/corrupt ~/.cache/bootc-installer/fisherman after staging
• Expected: GUI shows "failed to launch" error
• Verify: No hang, clear error message

7. Permission denied (pkexec cancelled)#

• Trigger: Deny the polkit prompt when fisherman tries to elevate
• Expected: Install fails immediately with permission error
• Verify: GUI shows actionable error, no orphan processes

8. Disk fills during install#

• Trigger: Fill /var/fisherman-tmp during image pull
• Expected: Podman/bootc fails with ENOSPC
• Verify: Error hint mentions disk space

Cleanup Verification#

After any failure:

• No leftover mounts at /mnt/fisherman-target
• No open LUKS devices (/dev/mapper/fisherman-*)
• No orphan fisherman processes (pgrep fisherman)
• Target disk not left with partial partition table (or user is warned)

Files to Change#

• tests/unit/test_failure_hints.py (new — test __extract_failure_hint() logic)
• tests/ui/test_done.py (failure state rendering)
• bootc_installer/views/done.py (improve hint extraction)
• fisherman/fisherman/cmd/fisherman/main.go (cleanup on error)

Acceptance#

• Each failure scenario produces a user-readable error hint
• Retry button works after failure (no stale state)
• No orphan processes or mounts after failure
• Unit tests cover all error hint categories