feat: Implement text buffers and textdocument notifications

Author: armsnyder

.gitignore

@@ -1 +1,2 @@
 /tmp/
+*.test

.golangci.yaml

@@ -1,12 +1,85 @@
-version: '2'
+version: "2"
 linters:
+  enable:
+    - depguard
+    - errcheck
+    - ginkgolinter
+    - gocritic
+    - godot
+    - gosec
+    - govet
+    - ineffassign
+    - misspell
+    - musttag
+    - nolintlint
+    - revive
+    - sloglint
+    - staticcheck
+    - unused
   settings:
-    govet:
-      disable:
-        - structtag # participle uses nonconventional tags
+    depguard:
+      rules:
+        lsp:
+          files: ["${base-path}/internal/lsp/*"]
+          deny:
+            - pkg: github.com/armsnyder/gdshader-language-server/internal/ast
+              desc: lsp and ast packages should not depend on each other
+            - pkg: github.com/armsnyder/gdshader-language-server/internal/app
+              desc: Library packages should not depend on app package
+        ast:
+          files: ["${base-path}/internal/ast/*"]
+          deny:
+            - pkg: github.com/armsnyder/gdshader-language-server/internal/lsp
+              desc: lsp and ast packages should not depend on each other
+            - pkg: github.com/armsnyder/gdshader-language-server/internal/app
+              desc: Library packages should not depend on app package
+        production:
+          files: ["!**/*_test.go"]
+          deny:
+            - pkg: github.com/armsnyder/gdshader-language-server/internal/testutil
+              desc: Test utilities should not be used in production code
+    gocritic:
+      enable-all: true
+      disabled-checks:
+        - whyNoLint
+    revive:
+      enable-all-rules: true
+      rules:
+        - name: add-constant
+          disabled: true # Too strict
+        - name: cognitive-complexity
+          arguments: [15] # Default 7
+        - name: cyclomatic
+          arguments: [15] # Default 10
+        - name: line-length-limit
+          disabled: true # Too strict
+        - name: max-public-structs
+          disabled: true # Too strict
+        - name: nested-structs
+          disabled: true # Too strict
+        - name: package-comments
+          disabled: true # Not a lib
+        - name: unused-receiver
+          disabled: true # Too common
+    sloglint:
+      msg-style: capitalized
+      key-naming-case: snake
+  exclusions:
+    rules:
+      - path: internal/lsp/types.go
+        text: comment .+ should be of the form # Types are documented with reference URLs
+      - path: internal/ast/types.go
+        text: malformed tag|bad syntax for struct tag # participle uses weird tags
+      - path: _test.go
+        text: dot-imports # gomega
+      - path: _test.go
+        text: function-length
+      - path: _test.go
+        linters: [gosec]
+      - linters: [gocritic]
+        text: contains a path separator # Not a valid check
 formatters:
-  enable:
-    - gofumpt
+  enable: [gofumpt]
   settings:
     gofumpt:
       module-path: github.com/armsnyder/gdshader-language-server

Makefile

@@ -0,0 +1,39 @@
+default: install
+
+all: reviewable install
+
+install:
+	go install
+
+COV_UNIT := $(PWD)/tmp/cover/unit
+COV_E2E := $(PWD)/tmp/cover/e2e
+COV_MERGED := $(PWD)/tmp/cover/merged
+
+reviewable: tidy fmt lint build test
+
+tidy:
+	go mod tidy
+
+fmt:
+	golangci-lint fmt
+
+lint:
+	golangci-lint run
+
+build:
+	go build ./...
+
+test:
+	rm -rf tmp/cover
+	mkdir -p $(COV_UNIT) $(COV_MERGED)
+	go test -cover ./... -args -test.gocoverdir=$(COV_UNIT)
+	go tool covdata merge -i $(COV_UNIT),$(COV_E2E) -o $(COV_MERGED)
+	$(call render_coverage, $(COV_UNIT))
+	$(call render_coverage, $(COV_E2E))
+	$(call render_coverage, $(COV_MERGED))
+
+define render_coverage
+	go tool covdata textfmt -i $(1) -o $(1)/cover.out
+	go tool cover -html $(1)/cover.out -o $(1)/cover.html
+	go tool covdata percent -i $(1)
+endef

README.md

@@ -68,11 +68,12 @@ existing code conventions.
 
 ```graphql
 .
-├── main.go # Entry point
+├── main.go  # Entry point
 └── internal
-    ├── ast     # .gdshader file parser library (application agnostic)
-    ├── handler # Main application logic
-    └── lsp     # LSP server library (application agnostic)
+    ├── app       # Main application logic
+    ├── ast       # .gdshader file parser library (application agnostic)
+    ├── lsp       # LSP server library (application agnostic)
+    └── testutil  # Test utilities for all packages
 ```
 
 ## License

e2e_test.go

@@ -67,7 +67,7 @@ func TestE2E(t *testing.T) {
 		expected += "Content-Length: " + strconv.Itoa(len(s)) + "\r\nContent-Type: application/vscode-jsonrpc; charset=utf-8\r\n\r\n" + s
 	}
 
-	expect(`{"jsonrpc":"2.0","id":1,"result":{"capabilities":{"textDocumentSync":{"openClose":true,"change":1}},"serverInfo":{"name":"gdshader-language-server","version":"development"}}}`)
+	expect(`{"jsonrpc":"2.0","id":1,"result":{"capabilities":{"textDocumentSync":{"openClose":true,"change":2},"completionProvider":{}},"serverInfo":{"name":"gdshader-language-server","version":"development"}}}`)
 	expect(`{"jsonrpc":"2.0","id":2,"result":null}`)
 
 	g.Expect(stdout.String()).To(BeComparableTo(string(expected)), "Output does not match expected")

go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/google/go-cmp v0.7.0
 	github.com/onsi/gomega v1.37.0
 	github.com/samber/lo v1.51.0
+	github.com/zyedidia/rope v0.0.0-20210616205215-37fbf22eab3a
 )
 
 require (

go.sum

@@ -20,6 +20,8 @@ github.com/onsi/gomega v1.37.0 h1:CdEG8g0S133B4OswTDC/5XPSzE1OeP29QOioj2PID2Y=
 github.com/onsi/gomega v1.37.0/go.mod h1:8D9+Txp43QWKhM24yyOBEdpkzN8FvJyAwecBgsU4KU0=
 github.com/samber/lo v1.51.0 h1:kysRYLbHy/MB7kQZf5DSN50JHmMsNEdeY24VzJFu7wI=
 github.com/samber/lo v1.51.0/go.mod h1:4+MXEGsJzbKGaUEQFKBq2xtfuznW9oz/WrgyzMzRoM0=
+github.com/zyedidia/rope v0.0.0-20210616205215-37fbf22eab3a h1:+VbuFCNAjzVffErUlm0TIAZClFxFZwJ1il6qtWrnIg8=
+github.com/zyedidia/rope v0.0.0-20210616205215-37fbf22eab3a/go.mod h1:IKo1js3O2gdESAUH9F3B33wlrRBnpJMJR/gXyY0a3ho=
 golang.org/x/net v0.37.0 h1:1zLorHbz+LYj7MQlSf1+2tPIIgibq2eL5xkrGk6f+2c=
 golang.org/x/net v0.37.0/go.mod h1:ivrbrMbzFq5J41QOQh0siUuly180yBYtLp+CKbEaFx8=
 golang.org/x/sys v0.31.0 h1:ioabZlmFYtWhL+TRYpcnNlLwhyxaM9kWTDEmfnprqik=

internal/app/handler.go

@@ -0,0 +1,58 @@
+package app
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/armsnyder/gdshader-language-server/internal/lsp"
+)
+
+// Handler encapsulates the logic of the Godot shader language server.
+type Handler struct {
+	documents map[string]*lsp.Document
+}
+
+// Initialize implements lsp.Handler.
+func (h *Handler) Initialize(context.Context, lsp.ClientCapabilities) (*lsp.ServerCapabilities, error) {
+	return &lsp.ServerCapabilities{
+		TextDocumentSync: &lsp.TextDocumentSyncOptions{
+			OpenClose: true,
+			Change:    lsp.SyncIncremental,
+		},
+		CompletionProvider: &lsp.CompletionOptions{},
+	}, nil
+}
+
+// DidOpenTextDocument implements lsp.Handler.
+func (h *Handler) DidOpenTextDocument(_ context.Context, params lsp.DidOpenTextDocumentParams) error {
+	doc := lsp.NewDocument([]byte(params.TextDocument.Text), nil)
+	if h.documents == nil {
+		h.documents = make(map[string]*lsp.Document)
+	}
+	h.documents[params.TextDocument.URI] = doc
+	return nil
+}
+
+// DidCloseTextDocument implements lsp.Handler.
+func (h *Handler) DidCloseTextDocument(_ context.Context, params lsp.DidCloseTextDocumentParams) error {
+	delete(h.documents, params.TextDocument.URI)
+	return nil
+}
+
+// DidChangeTextDocument implements lsp.Handler.
+func (h *Handler) DidChangeTextDocument(_ context.Context, params lsp.DidChangeTextDocumentParams) error {
+	doc, ok := h.documents[params.TextDocument.URI]
+	if !ok {
+		return fmt.Errorf("document not found: %s", params.TextDocument.URI)
+	}
+
+	for _, change := range params.ContentChanges {
+		if err := doc.ApplyChange(change); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+var _ lsp.Handler = &Handler{}

internal/ast/parser.go

@@ -12,6 +12,7 @@ func init() {
 	parser = participle.MustBuild[File]()
 }
 
+// Parse parses a .gdshader file into a tree of AST nodes.
 func Parse(filename string, reader io.Reader) (*File, error) {
 	return parser.Parse(filename, reader, participle.AllowTrailing(true))
 }

internal/ast/types.go

@@ -2,46 +2,55 @@ package ast
 
 import "github.com/alecthomas/participle/v2/lexer"
 
+// File is the root of a parsed .gdshader file.
 type File struct {
 	Pos          lexer.Position
 	Declarations []*Declaration `@@*`
 }
 
+// Declaration is a top-level declaration.
 type Declaration struct {
 	UniformDecl  *UniformDecl  `@@`
 	FunctionDecl *FunctionDecl `| @@`
 }
 
+// UniformDecl is a uniform variable declaration.
 type UniformDecl struct {
 	Type string `"uniform" @Ident`
 	Name string `@Ident ";"`
 }
 
+// FunctionDecl is a function declaration.
 type FunctionDecl struct {
 	ReturnType string     `@Ident`
 	Name       string     `@Ident "(" ")"`
 	Body       *BlockStmt `@@`
 }
 
+// BlockStmt is a block of statements enclosed in braces.
 type BlockStmt struct {
 	Stmts []*Stmt `"{" @@* "}"`
 }
 
+// Stmt is a code statement.
 type Stmt struct {
 	Assignment *Assignment `@@`
 }
 
+// Assignment is an assignment statement.
 type Assignment struct {
 	Left   string `@Ident`
 	Equals string `@"="`
 	Expr   *Expr  `@@`
 	Semi   string `@";"`
 }
 
+// Expr is an expression.
 type Expr struct {
 	FuncCall *FuncCall `@@`
 }
 
+// FuncCall is a function call exporession.
 type FuncCall struct {
 	FuncName string   `@Ident`
 	LParen   string   `@"("`