#256 - Implement body part damage effects — disabled limbs with mechanical consequences - aethyr/Aethyr

## Metadata - **Commit Message**: `feat(combat): implement disabled limb mechanical effects` - **Branch**: `feature/m4-limb-effects` ## Background and Context When a body part is disabled (HP reaches 0 on a non-lethal part), it has mechanical consequences: disabled arms cannot hold weapons or shields, disabled legs reduce movement and prevent stance changes, disabled hands drop held items. ## Expected Behavior The combat system checks body part status before allowing actions. Actions requiring a disabled body part are rejected with a descriptive message. Equipment in disabled hands is dropped. ## Acceptance Criteria - [ ] Disabled arm prevents attacks with weapons in that hand - [ ] Disabled hand causes held items to be dropped - [ ] Disabled leg prevents stance changes and movement-based actions - [ ] Both legs disabled prevents all movement actions - [ ] Disability effects are communicated to the player via combat messages ## Subtasks - [ ] Code: Add `limb_check(action)` method to CombatGrid that validates required body parts are functional - [ ] Code: Implement hand disability — drop items from disabled hand, publish `:item_dropped` event - [ ] Code: Implement arm disability — reject attack actions requiring that arm - [ ] Code: Implement leg disability — reject movement/stance actions, reduce AP if one leg disabled - [ ] Code: Integrate limb_check into combat resolution pipeline as a pre-action validation - [ ] Docs: Update YARD comments on affected classes and methods. Update relevant Docusaurus documentation pages if applicable. - [ ] Tests (Cucumber): Add `tests/unit/body_damage_effects.feature` covering disabled arm prevents attacks, disabled leg reduces movement, head damage causes stun. - [ ] Tests (Cucumber Integration): Add integration feature in `tests/integration/` for limb disability affecting combat actions. - [ ] Tests (Profiling): Run `bundle exec rake unit_profile` and verify no performance regressions. - [ ] Quality: Verify coverage >=97% via `bundle exec rake unit`. If coverage is <97% then review the current unit test coverage report at `build/tests/unit/coverage/` and use it to write new Cucumber based unit tests to improve code coverage. Specifically, write Cucumber/Gherkin style unit tests that are descriptively named and specifically improve coverage on whichever file has the most uncovered lines by writing tests that will target the uncovered lines in the report. Once that is done rerun `bundle exec rake unit` to verify all tests pass and coverage is above >=97%. Only mark this as complete once coverage is >=97%, if not repeat this task as many times as is needed until coverage reaches >=97%. - [ ] Quality: Run `bundle exec rake` (default task: unit tests with coverage) and `bundle exec rake integration`, fix any errors if needed ensuring both pass across **entire** code base, do not ignore any failure even if it seems unrelated to this commit, fix it. ## Definition of Done This issue is complete when: - All subtasks above are completed and checked off. - A Git commit is created where the **first line** of the commit message matches the Commit Message in Metadata exactly, followed by a blank line, then additional lines providing relevant details about the implementation. - The commit is pushed to the remote on the branch matching the **Branch** in Metadata exactly. - The commit is submitted as a **pull request** to `master`, reviewed, and **merged** before this issue is marked done.

freemo commented

2026-03-16 01:50:06 +00:00

Owner

Metadata

Commit Message: feat(combat): implement disabled limb mechanical effects
Branch: feature/m4-limb-effects

Background and Context

When a body part is disabled (HP reaches 0 on a non-lethal part), it has mechanical consequences: disabled arms cannot hold weapons or shields, disabled legs reduce movement and prevent stance changes, disabled hands drop held items.

Expected Behavior

The combat system checks body part status before allowing actions. Actions requiring a disabled body part are rejected with a descriptive message. Equipment in disabled hands is dropped.

Acceptance Criteria

Disabled arm prevents attacks with weapons in that hand
Disabled hand causes held items to be dropped
Disabled leg prevents stance changes and movement-based actions
Both legs disabled prevents all movement actions
Disability effects are communicated to the player via combat messages

Subtasks

Code: Add limb_check(action) method to CombatGrid that validates required body parts are functional
Code: Implement hand disability — drop items from disabled hand, publish :item_dropped event
Code: Implement arm disability — reject attack actions requiring that arm
Code: Implement leg disability — reject movement/stance actions, reduce AP if one leg disabled
Code: Integrate limb_check into combat resolution pipeline as a pre-action validation
Docs: Update YARD comments on affected classes and methods. Update relevant Docusaurus documentation pages if applicable.
Tests (Cucumber): Add tests/unit/body_damage_effects.feature covering disabled arm prevents attacks, disabled leg reduces movement, head damage causes stun.
Tests (Cucumber Integration): Add integration feature in tests/integration/ for limb disability affecting combat actions.
Tests (Profiling): Run bundle exec rake unit_profile and verify no performance regressions.
Quality: Verify coverage >=97% via bundle exec rake unit. If coverage is <97% then review the current unit test coverage report at build/tests/unit/coverage/ and use it to write new Cucumber based unit tests to improve code coverage. Specifically, write Cucumber/Gherkin style unit tests that are descriptively named and specifically improve coverage on whichever file has the most uncovered lines by writing tests that will target the uncovered lines in the report. Once that is done rerun bundle exec rake unit to verify all tests pass and coverage is above >=97%. Only mark this as complete once coverage is >=97%, if not repeat this task as many times as is needed until coverage reaches >=97%.
Quality: Run bundle exec rake (default task: unit tests with coverage) and bundle exec rake integration, fix any errors if needed ensuring both pass across entire code base, do not ignore any failure even if it seems unrelated to this commit, fix it.

Definition of Done

This issue is complete when:

All subtasks above are completed and checked off.
A Git commit is created where the first line of the commit message matches the Commit Message in Metadata exactly, followed by a blank line, then additional lines providing relevant details about the implementation.
The commit is pushed to the remote on the branch matching the Branch in Metadata exactly.
The commit is submitted as a pull request to master, reviewed, and merged before this issue is marked done.