feat: workspace folders

apps/expert/lib/expert/active_projects.ex

@@ -0,0 +1,50 @@
+defmodule Expert.ActiveProjects do
+  @moduledoc """
+  A cache to keep track of active projects.
+
+  Since GenLSP events happen asynchronously, we use an ets table to keep track of
+  them and avoid race conditions when we try to update the list of active projects.
+  """
+
+  use GenServer
+
+  def child_spec(_) do
+    %{
+      id: __MODULE__,
+      start: {__MODULE__, :start_link, []}
+    }
+  end
+
+  def start_link do
+    GenServer.start_link(__MODULE__, [], name: __MODULE__)
+  end
+
+  def init(_) do
+    __MODULE__ = :ets.new(__MODULE__, [:set, :named_table, :public, read_concurrency: true])
+    {:ok, nil}
+  end
+
+  def projects do
+    __MODULE__
+    |> :ets.tab2list()
+    |> Enum.map(fn {_, project} -> project end)
+  end
+
+  def add_projects(new_projects) when is_list(new_projects) do
+    for new_project <- new_projects do
+      # We use `:ets.insert_new/2` to avoid overwriting the cached project's entropy
+      :ets.insert_new(__MODULE__, {new_project.root_uri, new_project})
+    end
+  end
+
+  def remove_projects(removed_projects) when is_list(removed_projects) do
+    for removed_project <- removed_projects do
+      :ets.delete(__MODULE__, removed_project.root_uri)
+    end
+  end
+
+  def set_projects(new_projects) when is_list(new_projects) do
+    :ets.delete_all_objects(__MODULE__)
+    add_projects(new_projects)
+  end
+end

apps/expert/lib/expert/application.ex

@@ -18,6 +18,7 @@ defmodule Expert.Application do
       {GenLSP.Assigns, [name: Expert.Assigns]},
       {Task.Supervisor, name: :expert_task_queue},
       {GenLSP.Buffer, name: Expert.Buffer},
+      {Expert.ActiveProjects, []},
       {Expert,
        buffer: Expert.Buffer,
        task_supervisor: :expert_task_queue,

apps/expert/lib/expert/configuration.ex

@@ -5,20 +5,17 @@ defmodule Expert.Configuration do
 
   alias Expert.Configuration.Support
   alias Expert.Dialyzer
-  alias Forge.Project
   alias Forge.Protocol.Id
   alias GenLSP.Notifications.WorkspaceDidChangeConfiguration
   alias GenLSP.Requests
   alias GenLSP.Structures
 
-  defstruct projects: [],
-            support: nil,
+  defstruct support: nil,
             client_name: nil,
             additional_watched_extensions: nil,
             dialyzer_enabled?: false
 
   @type t :: %__MODULE__{
-          projects: [Project.t()],
           support: support | nil,
           client_name: String.t() | nil,
           additional_watched_extensions: [String.t()] | nil,
@@ -29,16 +26,11 @@ defmodule Expert.Configuration do
 
   @dialyzer {:nowarn_function, set_dialyzer_enabled: 2}
 
-  @spec new([Structures.WorkspaceFolder.t()], map(), String.t() | nil) :: t
-  def new(workspace_folders, %Structures.ClientCapabilities{} = client_capabilities, client_name) do
+  @spec new(map(), String.t() | nil) :: t
+  def new(%Structures.ClientCapabilities{} = client_capabilities, client_name) do
     support = Support.new(client_capabilities)
 
-    projects =
-      for %{uri: uri} <- workspace_folders do
-        Project.new(uri)
-      end
-
-    %__MODULE__{support: support, projects: projects, client_name: client_name}
+    %__MODULE__{support: support, client_name: client_name}
     |> tap(&set/1)
   end
 
@@ -147,30 +139,4 @@ defmodule Expert.Configuration do
   defp maybe_add_watched_extensions(%__MODULE__{} = old_config, _) do
     {:ok, old_config}
   end
-
-  @spec add_projects(t, [Project.t()]) :: t
-  def add_projects(%__MODULE__{} = config, projects) do
-    new_config =
-      for project <- projects, reduce: config do
-        config ->
-          if Enum.any?(config.projects, &(&1.root_uri == project.root_uri)) do
-            config
-          else
-            projects = [project | config.projects]
-            %__MODULE__{config | projects: projects}
-          end
-      end
-
-    set(new_config)
-
-    new_config
-  end
-
-  @spec remove_projects(t, [String.t()]) :: t
-  def remove_projects(%__MODULE__{} = config, projects) do
-    new_projects = Enum.reject(config.projects, &(&1.root_uri in projects))
-    new_config = %__MODULE__{config | projects: new_projects}
-    set(new_config)
-    new_config
-  end
 end

apps/expert/lib/expert/provider/handlers/code_action.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.CodeAction do
+  alias Expert.ActiveProjects
   alias Expert.Configuration
   alias Expert.EngineApi
   alias Forge.CodeAction
@@ -8,10 +9,11 @@ defmodule Expert.Provider.Handlers.CodeAction do
 
   def handle(
         %Requests.TextDocumentCodeAction{params: %Structures.CodeActionParams{} = params},
-        %Configuration{} = config
+        %Configuration{}
       ) do
     document = Forge.Document.Container.context_document(params, nil)
-    project = Project.project_for_document(config.projects, document)
+    projects = ActiveProjects.projects()
+    project = Project.project_for_document(projects, document)
     diagnostics = Enum.map(params.context.diagnostics, &to_code_action_diagnostic/1)
 
     code_actions =

apps/expert/lib/expert/provider/handlers/code_lens.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.CodeLens do
+  alias Expert.ActiveProjects
   alias Expert.Configuration
   alias Expert.EngineApi
   alias Expert.Provider.Handlers
@@ -14,10 +15,11 @@ defmodule Expert.Provider.Handlers.CodeLens do
 
   def handle(
         %Requests.TextDocumentCodeLens{params: %Structures.CodeLensParams{} = params},
-        %Configuration{} = config
+        %Configuration{}
       ) do
     document = Document.Container.context_document(params, nil)
-    project = Project.project_for_document(config.projects, document)
+    projects = ActiveProjects.projects()
+    project = Project.project_for_document(projects, document)
 
     document = Document.Container.context_document(params, nil)
 

apps/expert/lib/expert/provider/handlers/commands.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.Commands do
+  alias Expert.ActiveProjects
   alias Expert.Configuration
   alias Expert.EngineApi
   alias Forge.Project
@@ -25,14 +26,16 @@ defmodule Expert.Provider.Handlers.Commands do
 
   def handle(
         %Requests.WorkspaceExecuteCommand{params: %Structures.ExecuteCommandParams{} = params},
-        %Configuration{} = config
+        %Configuration{}
       ) do
+    projects = ActiveProjects.projects()
+
     response =
       case params.command do
         @reindex_name ->
-          project_names = Enum.map_join(config.projects, ", ", &Project.name/1)
+          project_names = Enum.map_join(projects, ", ", &Project.name/1)
           Logger.info("Reindex #{project_names}")
-          reindex_all(config.projects)
+          reindex_all(projects)
 
         invalid ->
           message = "#{invalid} is not a valid command"

apps/expert/lib/expert/provider/handlers/completion.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.Completion do
+  alias Expert.ActiveProjects
   alias Expert.CodeIntelligence
   alias Expert.Configuration
   alias Forge.Ast
@@ -14,10 +15,11 @@ defmodule Expert.Provider.Handlers.Completion do
         %Requests.TextDocumentCompletion{
           params: %Structures.CompletionParams{} = params
         },
-        %Configuration{} = config
+        %Configuration{}
       ) do
     document = Document.Container.context_document(params, nil)
-    project = Project.project_for_document(config.projects, document)
+    projects = ActiveProjects.projects()
+    project = Project.project_for_document(projects, document)
 
     completions =
       CodeIntelligence.Completion.complete(

apps/expert/lib/expert/provider/handlers/document_symbols.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.DocumentSymbols do
+  alias Expert.ActiveProjects
   alias Expert.Configuration
   alias Expert.EngineApi
   alias Forge.CodeIntelligence.Symbols
@@ -8,9 +9,10 @@ defmodule Expert.Provider.Handlers.DocumentSymbols do
   alias GenLSP.Requests
   alias GenLSP.Structures
 
-  def handle(%Requests.TextDocumentDocumentSymbol{} = request, %Configuration{} = config) do
+  def handle(%Requests.TextDocumentDocumentSymbol{} = request, %Configuration{}) do
     document = Document.Container.context_document(request.params, nil)
-    project = Project.project_for_document(config.projects, document)
+    projects = ActiveProjects.projects()
+    project = Project.project_for_document(projects, document)
 
     symbols =
       project

apps/expert/lib/expert/provider/handlers/find_references.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.FindReferences do
+  alias Expert.ActiveProjects
   alias Expert.Configuration
   alias Expert.EngineApi
   alias Forge.Ast
@@ -11,10 +12,11 @@ defmodule Expert.Provider.Handlers.FindReferences do
 
   def handle(
         %TextDocumentReferences{params: %Structures.ReferenceParams{} = params},
-        %Configuration{} = config
+        %Configuration{}
       ) do
     document = Forge.Document.Container.context_document(params, nil)
-    project = Project.project_for_document(config.projects, document)
+    projects = ActiveProjects.projects()
+    project = Project.project_for_document(projects, document)
     include_declaration? = !!params.context.include_declaration
 
     locations =

apps/expert/lib/expert/provider/handlers/formatting.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.Formatting do
+  alias Expert.ActiveProjects
   alias Expert.Configuration
   alias Expert.EngineApi
   alias Forge.Document.Changes
@@ -10,10 +11,11 @@ defmodule Expert.Provider.Handlers.Formatting do
 
   def handle(
         %Requests.TextDocumentFormatting{params: %Structures.DocumentFormattingParams{} = params},
-        %Configuration{} = config
+        %Configuration{}
       ) do
     document = Forge.Document.Container.context_document(params, nil)
-    project = Project.project_for_document(config.projects, document)
+    projects = ActiveProjects.projects()
+    project = Project.project_for_document(projects, document)
 
     case EngineApi.format(project, document) do
       {:ok, %Changes{} = document_edits} ->

apps/expert/lib/expert/provider/handlers/go_to_definition.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.GoToDefinition do
+  alias Expert.ActiveProjects
   alias Expert.Configuration
   alias Expert.EngineApi
   alias Forge.Project
@@ -11,10 +12,11 @@ defmodule Expert.Provider.Handlers.GoToDefinition do
         %Requests.TextDocumentDefinition{
           params: %Structures.DefinitionParams{} = params
         },
-        %Configuration{} = config
+        %Configuration{}
       ) do
     document = Forge.Document.Container.context_document(params, nil)
-    project = Project.project_for_document(config.projects, document)
+    projects = ActiveProjects.projects()
+    project = Project.project_for_document(projects, document)
 
     case EngineApi.definition(project, document, params.position) do
       {:ok, native_location} ->

apps/expert/lib/expert/provider/handlers/hover.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.Hover do
+  alias Expert.ActiveProjects
   alias Expert.Configuration
   alias Expert.EngineApi
   alias Expert.Provider.Markdown
@@ -17,10 +18,11 @@ defmodule Expert.Provider.Handlers.Hover do
         %Requests.TextDocumentHover{
           params: %Structures.HoverParams{} = params
         },
-        %Configuration{} = config
+        %Configuration{}
       ) do
     document = Document.Container.context_document(params, nil)
-    project = Project.project_for_document(config.projects, document)
+    projects = ActiveProjects.projects()
+    project = Project.project_for_document(projects, document)
 
     maybe_hover =
       with {:ok, _document, %Ast.Analysis{} = analysis} <-

apps/expert/lib/expert/provider/handlers/workspace_symbol.ex

@@ -1,4 +1,5 @@
 defmodule Expert.Provider.Handlers.WorkspaceSymbol do
+  alias Expert.ActiveProjects
   alias Expert.Configuration
   alias Expert.EngineApi
   alias Forge.CodeIntelligence.Symbols
@@ -11,11 +12,13 @@ defmodule Expert.Provider.Handlers.WorkspaceSymbol do
 
   def handle(
         %Requests.WorkspaceSymbol{params: %Structures.WorkspaceSymbolParams{} = params} = request,
-        %Configuration{} = config
+        %Configuration{}
       ) do
+    projects = ActiveProjects.projects()
+
     symbols =
       if String.length(params.query) > 1 do
-        Enum.flat_map(config.projects, &gather_symbols(&1, request))
+        Enum.flat_map(projects, &gather_symbols(&1, request))
       else
         []
       end