prometeu-studio/discussion/workflow/plans/PLN-0109-make-lsp-editorial-calls-capability-aware.md

id	ticket	title	status	created	ref_decisions	tags
PLN-0109	multi-frontend-compiler-vs-language-services	Make LSP editorial calls capability aware	done	2026-07-15	DEC-0041	compiler compiler-general studio lsp editor frontend multi-frontend

Briefing

DEC-0041 requires LSP and Studio consumers to query editorial capability availability before invoking editor-specific behavior. The current LSP bridge still contains PBS-specific editorial logic. This plan migrates LSP editorial calls to capability-aware provider lookup and graceful fallbacks.

Objective

Make LSP completion, hover, signature help, semantic tokens, and future editorial calls resolve the active frontend provider, consult optional language-service capabilities, and return deterministic neutral responses when capabilities are absent.

Dependencies

• Accepted decision: DEC-0041.
• PLN-0108 should expose PBS editor assistance through FrontendProvider.languageService().
• Existing FrontendRegistryService frontend lookup.
• Existing LSP baseline messages and tests.

Scope

• Update LSP bridge code to resolve frontend providers rather than hard-coding PBS editorial paths.
• Add fallback behavior for absent completion, hover, signature help, and semantic token capability.
• Preserve compiler-backed diagnostics through analyze/build paths.
• Keep PBS editorial behavior stable when its language service is present.
• Document or encode unsupported/neutral responses according to existing LSP baseline message shapes.

Non-Goals

• Add new LSP features.
• Change VSCode extension behavior beyond consuming existing baseline responses.
• Remove all PBS-specific code in one step if adapter compatibility still requires local mapping.
• Make semantic presentation metadata optional; only live semantic token production is optional.

Execution Method

1. Inspect prometeu-lsp/prometeu-lsp-v1/src/main/java/p/studio/lsp/services/compiler/CompilerLanguageServiceBridge.java and identify all direct PBS editorial calls.
2. Add a provider-resolution path using FrontendRegistryService or the existing registry abstraction for context.languageId().
3. For each editorial endpoint, query provider.languageService() and then the relevant capability before invoking implementation behavior.
4. Return neutral fallbacks when absent:
   • completion: incomplete false with empty items;
   • hover: absent/neutral hover content according to current baseline message constraints;
   • signature help: empty signatures with stable active indices;
   • semantic tokens: frontend legend/presentation where available and empty token list when live tokenization is absent.
5. Keep analyzeDocument compiler-diagnostic behavior on the compiler pipeline and do not require languageService().
6. Update tests to cover both PBS-present and capability-absent frontends.

Acceptance Criteria

• LSP editorial endpoints do not assume every compiler frontend has editor assistance.
• Absent editorial capabilities produce deterministic empty or neutral responses, not compiler failures.
• Compiler diagnostics still work without a language service.
• PBS editor assistance remains unchanged when PBS language service is available.
• Any remaining PBS-specific code is adapter-local and documented as temporary if not removed.

Tests

• Add LSP tests for a compile-only frontend or stub provider with no language service.
• Preserve existing CompilerLanguageServiceBridgeTest coverage for PBS completion, hover, signature help, and semantic tokens.
• Add regression coverage that analyzeDocument returns compiler diagnostics independently of editorial services.
• Run targeted LSP module tests.

Affected Artifacts

• prometeu-lsp/prometeu-lsp-v1/src/main/java/p/studio/lsp/services/compiler/CompilerLanguageServiceBridge.java
• prometeu-lsp/prometeu-lsp-v1/src/test/java/p/studio/lsp/services/compiler/CompilerLanguageServiceBridgeTest.java
• LSP baseline message types only if neutral response representation is currently insufficient.
• Frontend registry integration points used by LSP.