[Bug] FORCE_LAYOUT ignored with qmk command when using external userspace

Describe the Bug

According to https://github.com/qmk/qmk_firmware/blob/master/docs/feature_layouts.md the FORCE_LAYOUT variable can be used to specify a specific layout for a keyboard and keymap that support more than one layout.

For example:

• beekeeb/piantor supports community layouts split_3x6_3 and split_3x5_3
• manna-harbour_miryoku supports both of those community layouts
  • Since these userspaces have been moved out of qmk_firmware, here's the userspace I'm using: https://github.com/byronclark/qmk_userspace
• I can build for the split_3x6_3 layout using make like this make beekeeb/piantor:manna-harbour_miryoku FORCE_LAYOUT=split_3x6_3 QMK_USERSPACE=/home/byron/sandbox/current/qmk_userspace

To this point, everything is working as expected.

But I would like to be able to build with the qmk compile command like I do for my other keyboards that don't have this multiple layout issue. I would expect the following command to work: qmk compile -kb beekeeb/piantor -km manna-harbour_miryoku -e FORCE_LAYOUT=split_3x6_3.

Unfortunately, that command seems to always build the split_3x5_3 layout. Here's what the dry-run output shows:

❯ qmk compile -kb beekeeb/piantor -km manna-harbour_miryoku -e FORCE_LAYOUT=split_3x6_3 -n
Ψ Compiling keymap with gmake -r -R -f builddefs/build_keyboard.mk -s KEYBOARD=beekeeb/piantor KEYMAP=manna-harbour_miryoku KEYBOARD_FILESAFE=beekeeb_piantor TARGET=beekeeb_piantor_manna-harbour_miryoku INTERMEDIATE_OUTPUT=.build/obj_beekeeb_piantor_manna-harbour_miryoku VERBOSE=false COLOR=true SILENT=false QMK_BIN="qmk" FORCE_LAYOUT=split_3x6_3 QMK_USERSPACE=/home/byron/sandbox/current/qmk_userspace MAIN_KEYMAP_PATH_1=/home/byron/sandbox/current/qmk_userspace/layouts/split_3x5_3/manna-harbour_miryoku MAIN_KEYMAP_PATH_2=/home/byron/sandbox/current/qmk_userspace/layouts/split_3x5_3/manna-harbour_miryoku MAIN_KEYMAP_PATH_3=/home/byron/sandbox/current/qmk_userspace/layouts/split_3x5_3/manna-harbour_miryoku MAIN_KEYMAP_PATH_4=/home/byron/sandbox/current/qmk_userspace/layouts/split_3x5_3/manna-harbour_miryoku MAIN_KEYMAP_PATH_5=/home/byron/sandbox/current/qmk_userspace/layouts/split_3x5_3/manna-harbour_miryoku

The MAIN_KEYMAP_PATH_ variables are only set when using external userspace and seem to be overriding the FORCE_LAYOUT setting.

Keyboard Used

beekeeb/piantor

Link to product page (if applicable)

No response

Operating System

Linux

qmk doctor Output

Ψ QMK Doctor is checking your environment.
Ψ CLI version: 1.1.2
Ψ QMK home: /home/byron/sandbox/current/qmk_firmware
Ψ Detected Linux (Fedora Linux 39 (Workstation Edition)).
⚠ Missing or outdated udev rules for 'atmel-dfu' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'kiibohd' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'stm32-dfu' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'apm32-dfu' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'gd32v-dfu' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'wb32-dfu' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'bootloadhid' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'usbasploader' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'usbtinyisp' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'md-boot' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Detected ModemManager without the necessary udev rules. Please either disable it or set the appropriate udev rules if you are using a Pro Micro.
⚠ Missing or outdated udev rules for 'caterina' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
⚠ Missing or outdated udev rules for 'hid-bootloader' boards. Run 'sudo cp /home/byron/sandbox/current/qmk_firmware/util/udev/50-qmk.rules /etc/udev/rules.d/'.
Ψ Testing userspace candidate: /home/byron/sandbox/current/qmk_userspace -- Valid `qmk.json`
Ψ QMK userspace: /home/byron/sandbox/current/qmk_userspace
Ψ Userspace enabled: True
Ψ Git branch: user/byronclark
Ψ Repo version: 0.23.2
Ψ - Latest user/byronclark: 2023-12-21 09:32:19 +1100 (2661ee282a) -- [Bugfix] Manipulate deferred executor slot only if tokens match (#22722)
Ψ - Latest upstream/master: 2023-12-29 17:17:20 +0100 (fc20e0b014) -- Waffling60 iso rev e (#22733)
Ψ - Latest upstream/develop: 2023-12-29 16:17:49 +0000 (a081fc7301) -- Merge remote-tracking branch 'origin/master' into develop
Ψ - Common ancestor with upstream/master: 2023-12-21 09:32:19 +1100 (2661ee282a) -- [Bugfix] Manipulate deferred executor slot only if tokens match (#22722)
Ψ - Common ancestor with upstream/develop: 2023-12-21 09:32:19 +1100 (2661ee282a) -- [Bugfix] Manipulate deferred executor slot only if tokens match (#22722)
Ψ CLI installed in virtualenv.
☒ Can't find dfu-programmer in your path.
Would you like to install dependencies? [Y/n] n
Ψ Found arm-none-eabi-gcc version 13.1.0
Ψ Found avr-gcc version 13.1.0
⚠ We do not recommend avr-gcc newer than 8. Downgrading to 8.x is recommended.
Ψ Found avrdude version 6.4
⚠ Unknown version for dfu-programmer
Ψ Found dfu-util version 0.11
Ψ Submodules are up to date.
Ψ Submodule status:
Ψ - lib/chibios: 2023-04-15 13:48:04 +0000 --  (11edb1610)
Ψ - lib/chibios-contrib: 2023-07-17 11:39:05 +0200 --  (da78eb37)
Ψ - lib/googletest: 2021-06-11 06:37:43 -0700 --  (e2239ee6)
Ψ - lib/lufa: 2022-08-26 12:09:55 +1000 --  (549b97320)
Ψ - lib/vusb: 2022-06-13 09:18:17 +1000 --  (819dbc1)
Ψ - lib/printf: 2022-06-29 23:59:58 +0300 --  (c2e3b4e)
Ψ - lib/pico-sdk: 2023-02-12 20:19:37 +0100 --  (a3398d8)
Ψ - lib/lvgl: 2022-04-11 04:44:53 -0600 --  (e19410f8)
Ψ Major problems detected, please fix these problems before proceeding.
Ψ Check out the FAQ (https://docs.qmk.fm/#/faq_build) or join the QMK Discord (https://discord.gg/Uq7gcHh) for help.

Is AutoHotKey / Karabiner installed

• AutoHotKey (Windows)
• Karabiner (macOS)

Other keyboard-related software installed

No response

Additional Context

No response