initial commit of language server code

[gotwarlost]

Take the tip of the internal language server code and open source it as a monorepo module.

[Copilot]

Pull request overview

Initial open-source import of the internal function-hcl language server, packaging core LSP features (completion, hover, semantic tokens, folding, CRD-backed schemas) into a monorepo module.

Changes:

• Added schema lookup and utilities for the function-hcl DSL, including dynamic schema integration.
• Implemented decoder features: completion/hover/signature help, semantic tokens, folding ranges, and document symbols.
• Introduced module + CRD discovery/state tracking infrastructure (filesystem overlays, event bus, stores) and CLI commands.

Reviewed changes

Copilot reviewed 98 out of 240 changed files in this pull request and generated 15 comments.

Show a summary per file

File	Description
function-hcl-ls/internal/funchcl/schema/lookup.go	Standard + dynamic schema lookup for blocks/attributes and dependent body schemas.
function-hcl-ls/internal/funchcl/schema/api.go	Public schema APIs and helpers (status/apiVersion/kind filtering).
function-hcl-ls/internal/funchcl/doc.go	Package documentation for funchcl container.
function-hcl-ls/internal/funchcl/decoder/symbols/symbol_test.go	Interface conformance tests for symbol implementations.
function-hcl-ls/internal/funchcl/decoder/symbols/symbol.go	Symbol model types for document/workspace symbols.
function-hcl-ls/internal/funchcl/decoder/symbols/collect.go	Symbol collection from HCL syntax trees.
function-hcl-ls/internal/funchcl/decoder/symbols/api.go	Public API for file/workspace symbol queries.
function-hcl-ls/internal/funchcl/decoder/semtok/walk.go	Semantic token walker for HCL syntax trees.
function-hcl-ls/internal/funchcl/decoder/semtok/api.go	Public API for semantic token extraction.
function-hcl-ls/internal/funchcl/decoder/folding/folding_test.go	Tests for folding range collection logic.
function-hcl-ls/internal/funchcl/decoder/folding/folding.go	Folding range support optimized for lsp4ij/IntelliJ.
function-hcl-ls/internal/funchcl/decoder/decoderutils/utils.go	Shared helpers for template/string literal detection.
function-hcl-ls/internal/funchcl/decoder/context.go	Context interfaces for decoder operations (completion/hover/etc).
function-hcl-ls/internal/funchcl/decoder/completion/testdata/schemas/xrd.yaml	Test schema fixture for completion/hover behavior.
function-hcl-ls/internal/funchcl/decoder/completion/testdata/.xrd.yaml	Test XRD metadata fixture for completion context.
function-hcl-ls/internal/funchcl/decoder/completion/signature_test.go	Tests for function signature help at a cursor position.
function-hcl-ls/internal/funchcl/decoder/completion/signature.go	Signature help determination for function calls and active parameter.
function-hcl-ls/internal/funchcl/decoder/completion/schema-utils.go	Type/schema inference utilities used by hover/completion.
function-hcl-ls/internal/funchcl/decoder/completion/scaffold_test.go	Integration-style scaffold for completion tests with real module wiring.
function-hcl-ls/internal/funchcl/decoder/completion/hover.go	Hover entrypoints and block/label/attribute hover logic.
function-hcl-ls/internal/funchcl/decoder/completion/hover-expr.go	Expression hover logic and schema inference traversal.
function-hcl-ls/internal/funchcl/decoder/completion/helpers.go	Shared helpers for token ranges, byte access, snippets, and positioning.
function-hcl-ls/internal/funchcl/decoder/completion/expr-completion.go	Expression completion engine and dispatch by expression kind.
function-hcl-ls/internal/funchcl/decoder/completion/expr-completion-template.go	Template expression completion behavior.
function-hcl-ls/internal/funchcl/decoder/completion/expr-completion-ref.go	Reference completion for traversals into the target schema.
function-hcl-ls/internal/funchcl/decoder/completion/expr-completion-object.go	Object constructor completion (keys/values, recovery, edit ranges).
function-hcl-ls/internal/funchcl/decoder/completion/expr-completion-function.go	Function completion including namespaced recovery in syntax errors.
function-hcl-ls/internal/funchcl/decoder/completion/errors.go	Completion-related error types for consistent reporting.
function-hcl-ls/internal/funchcl/decoder/completion/completion_expr_test.go	Tests covering expression completion cases.
function-hcl-ls/internal/funchcl/decoder/completion/completion.go	Completion entrypoint routing and schema-aware body traversal.
function-hcl-ls/internal/funchcl/decoder/completion/api.go	Public API for completion and hover, behavior-controlled limits.
function-hcl-ls/internal/funchcl/decoder/behavior.go	Singleton language-server behavior flags (completion, folding, etc).
function-hcl-ls/internal/filesystem/os_fs.go	OS filesystem wrapper for the overlay FS abstraction.
function-hcl-ls/internal/filesystem/inmem.go	In-memory file and fileinfo/direntry types backing document overlays.
function-hcl-ls/internal/filesystem/filesystem.go	Two-layer FS overlay (document store preferred, OS fallback).
function-hcl-ls/internal/filesystem/document.go	Adapters from Document to fs.File/fs.FileInfo/fs.DirEntry.
function-hcl-ls/internal/features/modules/testdata/valid-mod-files/resources.tf	Module parsing test fixture (valid).
function-hcl-ls/internal/features/modules/testdata/valid-mod-files-with-extra-items/main.tf	Module parsing fixture with nested blocks and extra items.
function-hcl-ls/internal/features/modules/testdata/valid-mod-files-with-extra-items/.hidden.tf	Module parsing fixture ensuring hidden files behavior.
function-hcl-ls/internal/features/modules/testdata/invalid-mod-files/missing-brace.tf	Module parsing fixture (syntax error).
function-hcl-ls/internal/features/modules/testdata/invalid-mod-files/incomplete-block.tf	Module parsing fixture (incomplete content).
function-hcl-ls/internal/features/modules/testdata/invalid-links/resources.tf	Fixture for invalid file link scenarios.
function-hcl-ls/internal/features/modules/testdata/invalid-links/invalid.tf	Fixture for invalid file link scenarios.
function-hcl-ls/internal/features/modules/store/store.go	Module store for parsed files, diags, targets, and XRD metadata.
function-hcl-ls/internal/features/modules/parser.go	Module parser + derived target/reference computation hook-up.
function-hcl-ls/internal/features/modules/hooks.go	Completion hooks for apiVersion/kind from dynamic schema sets.
function-hcl-ls/internal/features/modules/events.go	Event-driven module parsing and diagnostics publishing.
function-hcl-ls/internal/features/modules/ctx.go	Path + completion contexts used by decoder features.
function-hcl-ls/internal/features/modules/api.go	Public modules feature API and dependency interfaces.
function-hcl-ls/internal/features/doc.go	Features package documentation.
function-hcl-ls/internal/features/crds/store/store_test.go	Tests for CRD store source discovery and callback behavior.
function-hcl-ls/internal/features/crds/store/store.go	CRD source discovery and schema propagation across sources/files.
function-hcl-ls/internal/features/crds/store/source-store.go	In-memory store for CRD source metadata and derived schemas.
function-hcl-ls/internal/features/crds/store/file-store.go	CRD file cache with checksum tracking and schema loading.
function-hcl-ls/internal/features/crds/store/api.go	Public CRD store API and change processing hooks.
function-hcl-ls/internal/features/crds/events.go	CRD feature event processing and filesystem-change reactions.
function-hcl-ls/internal/features/crds/cache.go	Offline CRD download/cache generation logic for package images.
function-hcl-ls/internal/features/crds/api.go	Public CRD feature API and wiring to publish “no sources” events.
function-hcl-ls/internal/eventbus/bus.go	Generic typed pub-sub topic implementation.
function-hcl-ls/internal/eventbus/api.go	Event bus APIs for open/edit/watch/diagnostics/no-sources topics.
function-hcl-ls/internal/document/store/store.go	In-memory document store tracking open docs and versions.
function-hcl-ls/internal/document/source/source.go	Source line splitting + range scanning for position conversions.
function-hcl-ls/internal/document/range.go	LSP-style range/position representation.
function-hcl-ls/internal/document/position.go	LSP position to byte-offset conversion (UTF-16 based).
function-hcl-ls/internal/document/handle_test.go	Tests for URI/path handle conversions.
function-hcl-ls/internal/document/handle.go	Document handle/dir handle helpers for URIs and filesystem paths.
function-hcl-ls/internal/document/errors.go	Document error types and helpers (not found, invalid pos).
function-hcl-ls/internal/document/document.go	Document model for open file content and derived line info.
function-hcl-ls/internal/document/dir_handle_test.go	Tests for dir handle normalization.
function-hcl-ls/internal/document/dir_handle.go	Directory handle normalization and URI/path conversion.
function-hcl-ls/internal/document/diff/diff.go	Diff-to-change conversion for document edits.
function-hcl-ls/internal/document/change_test.go	Tests for applying full and ranged document changes.
function-hcl-ls/internal/document/change.go	Apply LSP changes to the stored document content.
function-hcl-ls/internal/cmd/version.go	CLI command to print version/build metadata (json/text).
function-hcl-ls/internal/cmd/serve.go	CLI command to run the language server (stdio/TCP + profiling).
function-hcl-ls/internal/cmd/download-crds.go	CLI command to download CRDs using offline source definitions.
function-hcl-ls/internal/cmd/ast.go	CLI command to print AST node types and source excerpts.
function-hcl-ls/go.mod	Module definition + dependencies for the new language server module.
function-hcl-ls/README.md	High-level language server feature overview and build notes.
function-hcl-ls/Makefile	Build/test/lint targets for the module.
function-hcl-ls/.golangci.yml	Lint configuration with generated-code exclusions.
function-hcl-ls/.gitignore	Module-level ignore rules.

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Pull request overview

Copilot reviewed 98 out of 240 changed files in this pull request and generated 9 comments.

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Copilot reviewed 98 out of 240 changed files in this pull request and generated 7 comments.

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Pull request overview

Copilot reviewed 98 out of 240 changed files in this pull request and generated 3 comments.

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Copilot reviewed 98 out of 241 changed files in this pull request and generated 3 comments.

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[ydubreuil]

This is an incredible new addition for function-hcl!

Approving as I've been using the LSP internally at Elastic already.