initial commit of language server code

function-hcl-ls/.gitignore

@@ -0,0 +1,4 @@
+vendor/
+cover.out
+spec.md
+.claude/

function-hcl-ls/.golangci.yml

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+version: "2"
+linters:
+  exclusions:
+    rules:
+      # exclude unused checks from protocol generated code.
+      - path: internal/langserver/protocol/
+        linters:
+          - unused

function-hcl-ls/Makefile

@@ -0,0 +1,19 @@
+
+.PHONY: default
+default: build test lint
+
+.PHONY: build
+build:
+	go install ./...
+
+.PHONY: test
+test:
+	go test ./...
+
+.PHONY: fmt
+fmt:
+	gofumpt -w .
+
+.PHONY: lint
+lint:
+	golangci-lint run

function-hcl-ls/README.md

@@ -0,0 +1,35 @@
+function-hcl-ls
+---
+
+A language server implementation for function-hcl.
+
+Provides the following features:
+
+* Completion
+* Hover descriptions
+* Goto Declaration/ Find references
+* Semantic tokens
+* Validations and inline errors
+* Code folding
+
+Completion requires provider CRDs to be set up such that the language server can find type definitions. 
+
+The exact mechanics of how to set this up along with IDE integration will be documented under 
+[the docs page](https://crossplane-contrib.github.io/function-hcl/) when the client code is added to the repo.
+
+## Standing on the shoulders of giants
+
+This repo owes a lot to the [HCL language library](https://github.com/hashicorp/hcl-lang) and 
+the [Terraform language server](https://github.com/hashicorp/terraform-ls) implementation.
+
+This repo contains code copied from the above repos and modified for use. Since function-hcl is different
+enough from Terraform, the borrowed code did not work well for it but gave the authors a great starting
+point. A lot of refactoring has been done on both these copied codebases to make the language server
+work for function-hcl.
+
+In addition, the `go.mod` replaces the [HCL dependency](https://github.com/hashicorp/hcl) 
+with a [fork](https://github.com/gotwarlost/hcl) because of a [critical fix](https://github.com/hashicorp/hcl/pull/785) 
+for a [known issue](https://github.com/hashicorp/hcl/issues/597) that is needed.
+
+You cannot build this repo using `go install github.com/...` because of this. For source builds, you will need to clone 
+the repo and build it locally.

function-hcl-ls/go.mod

@@ -0,0 +1,107 @@
+module github.com/crossplane-contrib/function-hcl/function-hcl-ls
+
+go 1.25
+
+require (
+	github.com/apparentlymart/go-textseg v1.0.0
+	github.com/bmatcuk/doublestar/v4 v4.9.1
+	github.com/creachadair/jrpc2 v1.3.2
+	github.com/crossplane-contrib/function-hcl v0.1.4-0.20260213150247-c08e518c903a
+	github.com/crossplane/crossplane-runtime/v2 v2.1.0
+	github.com/crossplane/crossplane/v2 v2.1.3
+	github.com/ghodss/yaml v1.0.0
+	github.com/google/go-cmp v0.7.0
+	github.com/google/go-containerregistry v0.20.6
+	github.com/hashicorp/go-uuid v1.0.3
+	github.com/hashicorp/go-version v1.7.0
+	github.com/hashicorp/hcl/v2 v2.24.0
+	github.com/pkg/errors v0.9.1
+	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2
+	github.com/spf13/cobra v1.9.1
+	github.com/stretchr/testify v1.11.1
+	github.com/zclconf/go-cty v1.17.0
+	github.com/zclconf/go-cty-debug v0.0.0-20240509010212-0d6042c53940
+	k8s.io/api v0.34.2
+	k8s.io/apiextensions-apiserver v0.34.2
+	k8s.io/apimachinery v0.34.2
+)
+
+replace github.com/hashicorp/hcl/v2 => github.com/gotwarlost/hcl/v2 v2.0.0-20260210011329-0927384ef641
+
+require (
+	dario.cat/mergo v1.0.2 // indirect
+	github.com/agext/levenshtein v1.2.3 // indirect
+	github.com/apparentlymart/go-cidr v1.1.0 // indirect
+	github.com/apparentlymart/go-textseg/v15 v15.0.0 // indirect
+	github.com/containerd/stargz-snapshotter/estargz v0.16.3 // indirect
+	github.com/creachadair/mds v0.25.1 // indirect
+	github.com/crossplane/crossplane-runtime v1.20.0 // indirect
+	github.com/crossplane/function-sdk-go v0.4.0 // indirect
+	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
+	github.com/docker/cli v28.2.2+incompatible // indirect
+	github.com/docker/distribution v2.8.3+incompatible // indirect
+	github.com/docker/docker-credential-helpers v0.9.3 // indirect
+	github.com/emicklei/go-restful/v3 v3.12.2 // indirect
+	github.com/evanphx/json-patch/v5 v5.9.11 // indirect
+	github.com/fxamacker/cbor/v2 v2.9.0 // indirect
+	github.com/go-logr/logr v1.4.3 // indirect
+	github.com/go-logr/zapr v1.3.0 // indirect
+	github.com/go-openapi/jsonpointer v0.21.0 // indirect
+	github.com/go-openapi/jsonreference v0.21.0 // indirect
+	github.com/go-openapi/swag v0.23.0 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/google/gnostic-models v0.7.0 // indirect
+	github.com/google/uuid v1.6.0 // indirect
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/klauspost/compress v1.18.0 // indirect
+	github.com/mailru/easyjson v0.7.7 // indirect
+	github.com/mattn/go-colorable v0.1.14 // indirect
+	github.com/mitchellh/go-homedir v1.1.0 // indirect
+	github.com/mitchellh/go-wordwrap v1.0.1 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.3-0.20250322232337-35a7c28c31ee // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/onsi/ginkgo/v2 v2.23.3 // indirect
+	github.com/onsi/gomega v1.37.0 // indirect
+	github.com/opencontainers/go-digest v1.0.0 // indirect
+	github.com/opencontainers/image-spec v1.1.1 // indirect
+	github.com/sirupsen/logrus v1.9.3 // indirect
+	github.com/spf13/afero v1.12.0 // indirect
+	github.com/spf13/pflag v1.0.6 // indirect
+	github.com/vbatts/tar-split v0.12.1 // indirect
+	github.com/x448/float16 v0.8.4 // indirect
+	github.com/zclconf/go-cty-yaml v1.1.0 // indirect
+	go.opentelemetry.io/otel v1.38.0 // indirect
+	go.uber.org/multierr v1.11.0 // indirect
+	go.uber.org/zap v1.27.0 // indirect
+	go.yaml.in/yaml/v2 v2.4.2 // indirect
+	go.yaml.in/yaml/v3 v3.0.4 // indirect
+	golang.org/x/crypto v0.45.0 // indirect
+	golang.org/x/mod v0.30.0 // indirect
+	golang.org/x/net v0.47.0 // indirect
+	golang.org/x/oauth2 v0.30.0 // indirect
+	golang.org/x/sync v0.18.0 // indirect
+	golang.org/x/sys v0.38.0 // indirect
+	golang.org/x/term v0.37.0 // indirect
+	golang.org/x/text v0.31.0 // indirect
+	golang.org/x/time v0.11.0 // indirect
+	golang.org/x/tools v0.39.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20250303144028-a0af3efb3deb // indirect
+	google.golang.org/grpc v1.72.1 // indirect
+	google.golang.org/protobuf v1.36.6 // indirect
+	gopkg.in/evanphx/json-patch.v4 v4.12.0 // indirect
+	gopkg.in/inf.v0 v0.9.1 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+	k8s.io/client-go v0.34.2 // indirect
+	k8s.io/klog/v2 v2.130.1 // indirect
+	k8s.io/kube-openapi v0.0.0-20250710124328-f3f2b991d03b // indirect
+	k8s.io/utils v0.0.0-20250604170112-4c0f3b243397 // indirect
+	sigs.k8s.io/controller-runtime v0.22.2 // indirect
+	sigs.k8s.io/json v0.0.0-20241014173422-cfa47c3a1cc8 // indirect
+	sigs.k8s.io/randfill v1.0.0 // indirect
+	sigs.k8s.io/structured-merge-diff/v6 v6.3.0 // indirect
+	sigs.k8s.io/yaml v1.6.0 // indirect
+)