feat(lsp): completions for imports and fields #35

Author: vknabel

.devcontainer/Dockerfile

@@ -1,7 +1,7 @@
 # See here for image contents: https://github.com/microsoft/vscode-dev-containers/tree/v0.202.5/containers/go/.devcontainer/base.Dockerfile
 
 # [Choice] Go version (use -bullseye variants on local arm64/Apple Silicon): 1, 1.16, 1.17, 1-bullseye, 1.16-bullseye, 1.17-bullseye, 1-buster, 1.16-buster, 1.17-buster
-ARG VARIANT="1.17-bullseye"
+ARG VARIANT="1.19-bullseye"
 FROM mcr.microsoft.com/vscode/devcontainers/go:0-${VARIANT}
 
 # [Choice] Node.js version: none, lts/*, 16, 14, 12, 10

CHANGELOG.md

@@ -7,6 +7,8 @@
 - stdlib: new function `lists.prepend` for prepending lists
 - fix: improved type switch error message
 - fix: improved stdlib not found error message
+- lsp: complete importable modules #35
+- lsp: field completions #35
 - chore: bump dependencies
 
 ## v0.0.17

go.mod

@@ -5,7 +5,7 @@ go 1.19
 require (
 	github.com/smacker/go-tree-sitter v0.0.0-20221023091341-2009a4db91e4
 	github.com/spf13/cobra v1.6.1
-	github.com/tliron/glsp v0.1.1
+	github.com/tliron/glsp v0.1.2-0.20220804144236-0fe570f215a5
 	github.com/tliron/kutil v0.1.62
 	github.com/vknabel/tree-sitter-lithia v0.2.2-0.20221001133044-2d70ec255b9f
 )

go.sum

@@ -47,8 +47,8 @@ github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.4 h1:wZRexSlwd7ZXfKINDLsO4r7WBt3gTKONc6K/VesHvHM=
 github.com/stretchr/testify v1.7.4/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
-github.com/tliron/glsp v0.1.1 h1:GNNgUX9p1Q9MoPQooJoZ0+WaLL03EkhcKZUYJAtiNqs=
-github.com/tliron/glsp v0.1.1/go.mod h1:RVyVKeY3U+Nlc3DRklUiaegNsQyjzNTEool6YWh1v7g=
+github.com/tliron/glsp v0.1.2-0.20220804144236-0fe570f215a5 h1:Qqqhhlk6YA+UsQCdWKStjHzK6UqMjblw5jZ0xJY2DLY=
+github.com/tliron/glsp v0.1.2-0.20220804144236-0fe570f215a5/go.mod h1:Hqz7gzsJnxJidRXTUsvqdmk1xeh4zdlB8B2Jv3244RU=
 github.com/tliron/kutil v0.1.62 h1:Nj4avenQO9t9QNaD6qXf1DsdyOjQrORIJjoc0FCnsBg=
 github.com/tliron/kutil v0.1.62/go.mod h1:Mo1pAtg/9yG3ClnUv32Hrl+t0BFFCg49RpCjHG3sY7c=
 github.com/vknabel/tree-sitter-lithia v0.2.2-0.20221001133044-2d70ec255b9f h1:6OyIrB3iRHe1zZq+VEBmxIk2WVTuNWdJrpoG91cThYU=

langsrv/handler-completion.go

@@ -7,12 +7,68 @@ import (
 	"github.com/tliron/glsp"
 	protocol "github.com/tliron/glsp/protocol_3_16"
 	"github.com/vknabel/lithia/ast"
+	"github.com/vknabel/lithia/parser"
 )
 
 func textDocumentCompletion(context *glsp.Context, params *protocol.CompletionParams) (interface{}, error) {
 	rc := NewReqContextAtPosition(&params.TextDocumentPositionParams)
 
+	targetNode, err := rc.findNode()
+	if err != nil {
+		return nil, err
+	}
+
 	completionItems := []protocol.CompletionItem{}
+
+	switch targetNode.Type() {
+	case parser.TYPE_NODE_IMPORT_DECLARATION:
+		kind := protocol.CompletionItemKindModule
+		mods, err := ls.resolver.ImportableModules(rc.module.Package())
+		if err != nil {
+			return nil, err
+		}
+		for _, mod := range mods {
+			completionItems = append(completionItems, protocol.CompletionItem{
+				Label: string(mod.RelativeName),
+				Kind:  &kind,
+				Documentation: &protocol.MarkupContent{
+					Kind:  protocol.MarkupKindMarkdown,
+					Value: fmt.Sprintf("`import %s`", mod.RelativeName),
+				},
+			})
+		}
+		return completionItems, nil
+	case parser.TYPE_NODE_MEMBER_ACCESS, ".":
+		decls := rc.accessibleDeclarations(context)
+
+		for _, imported := range decls {
+			switch decl := imported.decl.(type) {
+			case ast.DeclData:
+				for _, field := range decl.Fields {
+					insertText := string(field.DeclName())
+					var detail string
+					if imported.decl.Meta().ModuleName != "" {
+						detail = string(imported.decl.Meta().ModuleName) +
+							"." +
+							string(imported.decl.DeclName()) +
+							"." +
+							string(field.DeclName())
+					}
+
+					completionItems = append(completionItems, protocol.CompletionItem{
+						Label:            string(field.DeclName()),
+						Kind:             completionItemKindForDecl(imported.decl),
+						InsertText:       &insertText,
+						Detail:           &detail,
+						CommitCharacters: []string{"."},
+						Documentation:    documentationMarkupContentForDecl(imported.decl),
+					})
+				}
+			}
+		}
+		return completionItems, nil
+	}
+
 	for _, imported := range rc.accessibleDeclarations(context) {
 		insertText := insertTextForImportedDecl(imported)
 		var detail string

langsrv/lang-server.go

@@ -38,6 +38,8 @@ func init() {
 		Shutdown:    shutdown,
 		SetTrace:    setTrace,
 
+		CancelRequest: func(context *glsp.Context, params *protocol.CancelParams) error { return nil },
+
 		TextDocumentDidOpen:   textDocumentDidOpen,
 		TextDocumentDidChange: textDocumentDidChange,
 		TextDocumentDidClose:  func(context *glsp.Context, params *protocol.DidCloseTextDocumentParams) error { return nil },

resolution/module-resolver.go

@@ -1,6 +1,7 @@
 package resolution
 
 import (
+	"os"
 	"path"
 	"path/filepath"
 	"strings"
@@ -41,7 +42,7 @@ type ResolvedModule struct {
 	packageRef *ResolvedPackage
 	// all modules of this package are relative to this path
 	// might contain the package manifest file
-	relativeName ast.ModuleName
+	RelativeName ast.ModuleName
 	Path         string
 	Files        []string
 }
@@ -83,8 +84,12 @@ func (mr *ModuleResolver) ResolvePackageForReferenceFile(referenceFile string) R
 		manifestPath := filepath.Join(path.Dir(referenceFile), candidates, mr.manifestName)
 		if _, err := world.Current.FS.Stat(manifestPath); err == nil {
 			packagePath := path.Dir(manifestPath)
+			packageName := path.Base(packagePath)
+			if packageName == "/" || packageName == "." {
+				packageName = mr.defaultPackageName
+			}
 			return ResolvedPackage{
-				Name: mr.defaultPackageName,
+				Name: packageName,
 				Path: packagePath,
 				Manifest: &PackageManifest{
 					Path: manifestPath,
@@ -130,7 +135,7 @@ func (mr *ModuleResolver) CreateSingleFileModule(pkg ResolvedPackage, file strin
 	uniform := strings.ReplaceAll(trimmed, ".", "_")
 	return ResolvedModule{
 		packageRef:   &pkg,
-		relativeName: ast.ModuleName(uniform),
+		RelativeName: ast.ModuleName(uniform),
 		Path:         file,
 		Files:        []string{file},
 	}
@@ -192,7 +197,7 @@ func (mr *ModuleResolver) resolveModuleWithinPackage(pkg ResolvedPackage, module
 	files, err := world.Current.FS.Glob(path.Join(modulePath, mr.lithiaSourceGlob))
 	return ResolvedModule{
 		packageRef:   &pkg,
-		relativeName: ast.ModuleName(strings.Join(moduleParts, ".")),
+		RelativeName: ast.ModuleName(strings.Join(moduleParts, ".")),
 		Path:         modulePath,
 		Files:        files,
 	}, err
@@ -203,13 +208,37 @@ func (mod ResolvedModule) Package() ResolvedPackage {
 }
 
 func (mod ResolvedModule) AbsoluteModuleName() ast.ModuleName {
-	if mod.relativeName == "" {
+	if mod.RelativeName == "" {
 		return ast.ModuleName(mod.Package().Name)
 	} else {
-		return ast.ModuleName(mod.packageRef.Name) + "." + mod.relativeName
+		return ast.ModuleName(mod.packageRef.Name) + "." + mod.RelativeName
 	}
 }
 
 func removingFilePrefix(str string) string {
 	return strings.TrimPrefix(str, "file://")
 }
+
+func (mr *ModuleResolver) ImportableModules(pkg ResolvedPackage) ([]ResolvedModule, error) {
+	var modules []ResolvedModule
+
+	possibleModuleNames := make([]string, 0)
+	for _, root := range mr.externalImportRoots {
+		dirs, err := os.ReadDir(root)
+		if err != nil {
+			return nil, err
+		}
+		for _, dir := range dirs {
+			if dir.IsDir() {
+				possibleModuleNames = append(possibleModuleNames, dir.Name())
+			}
+		}
+	}
+
+	for _, modName := range possibleModuleNames {
+		mod := mr.ResolvePackageAndModuleForReferenceFile(modName)
+		modules = append(modules, mod)
+	}
+
+	return modules, nil
+}