feat(definition,references): module attributes (#215)

Author: biletskyy

lib/next_ls.ex

@@ -215,6 +215,20 @@ defmodule NextLS do
                   [module, "alias"]
                 )
 
+              {:attribute, module, attribute} ->
+                DB.query(
+                  database,
+                  ~Q"""
+                  SELECT file, start_line, end_line, start_column, end_column
+                  FROM "references" as refs
+                  WHERE refs.identifier = ?
+                    AND refs.type = ?
+                    AND refs.module = ?
+                    AND refs.source = 'user'
+                  """,
+                  [attribute, "attribute", module]
+                )
+
               :unknown ->
                 []
             end
@@ -266,7 +280,7 @@ defmodule NextLS do
         filtered_symbols =
           for {pid, _} <- entries, symbol <- symbols.(pid), score = fuzzy_match(symbol.name, query, case_sensitive?) do
             name =
-              if symbol.type != "defstruct" do
+              if symbol.type not in ["defstruct", "attribute"] do
                 "#{symbol.type} #{symbol.name}"
               else
                 "#{symbol.name}"
@@ -679,6 +693,7 @@ defmodule NextLS do
 
   defp elixir_kind_to_lsp_kind("defmodule"), do: GenLSP.Enumerations.SymbolKind.module()
   defp elixir_kind_to_lsp_kind("defstruct"), do: GenLSP.Enumerations.SymbolKind.struct()
+  defp elixir_kind_to_lsp_kind("attribute"), do: GenLSP.Enumerations.SymbolKind.property()
 
   defp elixir_kind_to_lsp_kind(kind) when kind in ["def", "defp", "defmacro", "defmacrop"],
     do: GenLSP.Enumerations.SymbolKind.function()
@@ -737,11 +752,17 @@ defmodule NextLS do
       [[module, "defmacro", function]] ->
         {:function, module, function}
 
+      [[module, "attribute", attribute]] ->
+        {:attribute, module, attribute}
+
       _unknown_definition ->
         case DB.query(database, reference_query, [file, line, col]) do
           [[function, "function", module]] ->
             {:function, module, function}
 
+          [[attribute, "attribute", module]] ->
+            {:attribute, module, attribute}
+
           [[_alias, "alias", module]] ->
             {:module, module}
 

lib/next_ls/ast_helpers.ex

@@ -0,0 +1,75 @@
+defmodule NextLS.ASTHelpers do
+  @moduledoc false
+
+  @spec get_attribute_reference_name(String.t(), integer(), integer()) :: String.t() | nil
+  def get_attribute_reference_name(file, line, column) do
+    ast = ast_from_file(file)
+
+    {_ast, name} =
+      Macro.prewalk(ast, nil, fn
+        {:@, [line: ^line, column: ^column], [{name, _meta, nil}]} = ast, _acc -> {ast, "@#{name}"}
+        other, acc -> {other, acc}
+      end)
+
+    name
+  end
+
+  @spec get_module_attributes(String.t(), module()) :: [{atom(), String.t(), integer(), integer()}]
+  def get_module_attributes(file, module) do
+    reserved_attributes = Module.reserved_attributes()
+
+    symbols = parse_symbols(file, module)
+
+    Enum.filter(symbols, fn
+      {:attribute, "@" <> name, _, _} ->
+        not Map.has_key?(reserved_attributes, String.to_atom(name))
+
+      _other ->
+        false
+    end)
+  end
+
+  defp parse_symbols(file, module) do
+    ast = ast_from_file(file)
+
+    {_ast, %{symbols: symbols}} =
+      Macro.traverse(ast, %{modules: [], symbols: []}, &prewalk/2, &postwalk(&1, &2, module))
+
+    symbols
+  end
+
+  # add module name to modules stack on enter
+  defp prewalk({:defmodule, _, [{:__aliases__, _, module_name_atoms} | _]} = ast, acc) do
+    modules = [module_name_atoms | acc.modules]
+    {ast, %{acc | modules: modules}}
+  end
+
+  defp prewalk(ast, acc), do: {ast, acc}
+
+  defp postwalk({:@, meta, [{name, _, args}]} = ast, acc, module) when is_list(args) do
+    ast_module =
+      acc.modules
+      |> Enum.reverse()
+      |> List.flatten()
+      |> Module.concat()
+
+    if module == ast_module do
+      symbols = [{:attribute, "@#{name}", meta[:line], meta[:column]} | acc.symbols]
+      {ast, %{acc | symbols: symbols}}
+    else
+      {ast, acc}
+    end
+  end
+
+  # remove module name from modules stack on exit
+  defp postwalk({:defmodule, _, [{:__aliases__, _, _modules} | _]} = ast, acc, _module) do
+    [_exit_mudule | modules] = acc.modules
+    {ast, %{acc | modules: modules}}
+  end
+
+  defp postwalk(ast, acc, _module), do: {ast, acc}
+
+  defp ast_from_file(file) do
+    file |> File.read!() |> Code.string_to_quoted!(columns: true)
+  end
+end

lib/next_ls/db.ex

@@ -61,6 +61,7 @@ defmodule NextLS.DB do
       struct: struct,
       file: file,
       defs: defs,
+      symbols: symbols,
       source: source
     } = symbol
 
@@ -106,6 +107,17 @@ defmodule NextLS.DB do
       )
     end
 
+    for {type, name, line, column} <- symbols do
+      __query__(
+        {conn, s.logger},
+        ~Q"""
+        INSERT INTO symbols (module, file, type, name, line, 'column', source)
+            VALUES (?, ?, ?, ?, ?, ?, ?);
+        """,
+        [mod, file, type, name, line, column, source]
+      )
+    end
+
     {:noreply, s}
   end
 

lib/next_ls/definition.ex

@@ -41,6 +41,9 @@ defmodule NextLS.Definition do
           "function" ->
             [module, identifier]
 
+          "attribute" ->
+            [module, identifier]
+
           _ ->
             nil
         end

lib/next_ls/runtime/sidecar.ex

@@ -2,6 +2,7 @@ defmodule NextLS.Runtime.Sidecar do
   @moduledoc false
   use GenServer
 
+  alias NextLS.ASTHelpers
   alias NextLS.DB
 
   def start_link(args) do
@@ -15,11 +16,20 @@ defmodule NextLS.Runtime.Sidecar do
   end
 
   def handle_info({:tracer, payload}, state) do
+    attributes = ASTHelpers.get_module_attributes(payload.file, payload.module)
+    payload = Map.put_new(payload, :symbols, attributes)
     DB.insert_symbol(state.db, payload)
 
     {:noreply, state}
   end
 
+  def handle_info({{:tracer, :reference, :attribute}, payload}, state) do
+    name = ASTHelpers.get_attribute_reference_name(payload.file, payload.meta[:line], payload.meta[:column])
+    if name, do: DB.insert_reference(state.db, %{payload | identifier: name})
+
+    {:noreply, state}
+  end
+
   def handle_info({{:tracer, :reference}, payload}, state) do
     DB.insert_reference(state.db, payload)
 

priv/monkey/_next_ls_private_compiler.ex

@@ -84,6 +84,27 @@ defmodule NextLSPrivate.Tracer do
     :ok
   end
 
+  def trace({:imported_macro, meta, _module, :@, arity}, env) do
+    parent = parent_pid()
+
+    Process.send(
+      parent,
+      {{:tracer, :reference, :attribute},
+       %{
+         meta: meta,
+         identifier: :@,
+         arity: arity,
+         file: env.file,
+         type: :attribute,
+         module: env.module,
+         source: @source
+       }},
+      []
+    )
+
+    :ok
+  end
+
   def trace({type, meta, module, func, arity}, env) when type in [:remote_function, :remote_macro, :imported_macro] do
     parent = parent_pid()
 

test/next_ls/definition_test.exs

@@ -403,4 +403,159 @@ defmodule NextLS.DefinitionTest do
                     500
     end
   end
+
+  describe "attribute" do
+    @describetag root_paths: ["my_proj"]
+    setup %{tmp_dir: tmp_dir} do
+      File.mkdir_p!(Path.join(tmp_dir, "my_proj/lib"))
+      File.write!(Path.join(tmp_dir, "my_proj/mix.exs"), mix_exs())
+      [cwd: tmp_dir]
+    end
+
+    setup %{cwd: cwd} do
+      bar = Path.join(cwd, "my_proj/lib/bar.ex")
+
+      File.write!(bar, """
+      defmodule Bar do
+        @my_attr 1
+        @second_attr 2
+
+        @spec run() :: :ok | :error
+        def run() do
+          if @my_attr == 1 do
+            :ok
+          else
+            {:error, @second_attr}
+          end
+        end
+
+        defmodule Inner do
+          @inner_attr 123
+
+          def foo(a) do
+            if a, do: @inner_attr
+          end
+        end
+
+        def foo() do
+          :nothing
+        end
+      end
+
+      defmodule TopSecond.Some.Long.Name do
+        @top_second_attr "something"
+
+        def run_second do
+          {:error, @top_second_attr}
+        end
+      end
+      """)
+
+      [bar: bar]
+    end
+
+    setup :with_lsp
+
+    test "go to attribute definition", %{client: client, bar: bar} do
+      assert :ok == notify(client, %{method: "initialized", jsonrpc: "2.0", params: %{}})
+      assert_request(client, "client/registerCapability", fn _params -> nil end)
+      assert_notification "$/progress", %{"value" => %{"kind" => "end", "message" => "Finished indexing!"}}
+
+      uri = uri(bar)
+
+      request(client, %{
+        method: "textDocument/definition",
+        id: 4,
+        jsonrpc: "2.0",
+        params: %{
+          position: %{line: 6, character: 9},
+          textDocument: %{uri: uri}
+        }
+      })
+
+      assert_result 4,
+                    %{
+                      "range" => %{
+                        "start" => %{
+                          "line" => 1,
+                          "character" => 2
+                        },
+                        "end" => %{
+                          "line" => 1,
+                          "character" => 2
+                        }
+                      },
+                      "uri" => ^uri
+                    },
+                    500
+    end
+
+    test "go to attribute definition in second module", %{client: client, bar: bar} do
+      assert :ok == notify(client, %{method: "initialized", jsonrpc: "2.0", params: %{}})
+      assert_request(client, "client/registerCapability", fn _params -> nil end)
+      assert_notification "$/progress", %{"value" => %{"kind" => "end", "message" => "Finished indexing!"}}
+
+      uri = uri(bar)
+
+      request(client, %{
+        method: "textDocument/definition",
+        id: 4,
+        jsonrpc: "2.0",
+        params: %{
+          position: %{line: 30, character: 17},
+          textDocument: %{uri: uri}
+        }
+      })
+
+      assert_result 4,
+                    %{
+                      "range" => %{
+                        "start" => %{
+                          "line" => 27,
+                          "character" => 2
+                        },
+                        "end" => %{
+                          "line" => 27,
+                          "character" => 2
+                        }
+                      },
+                      "uri" => ^uri
+                    },
+                    500
+    end
+
+    test "go to attribute definition in inner module", %{client: client, bar: bar} do
+      assert :ok == notify(client, %{method: "initialized", jsonrpc: "2.0", params: %{}})
+      assert_request(client, "client/registerCapability", fn _params -> nil end)
+      assert_notification "$/progress", %{"value" => %{"kind" => "end", "message" => "Finished indexing!"}}
+
+      uri = uri(bar)
+
+      request(client, %{
+        method: "textDocument/definition",
+        id: 4,
+        jsonrpc: "2.0",
+        params: %{
+          position: %{line: 17, character: 20},
+          textDocument: %{uri: uri}
+        }
+      })
+
+      assert_result 4,
+                    %{
+                      "range" => %{
+                        "start" => %{
+                          "line" => 14,
+                          "character" => 4
+                        },
+                        "end" => %{
+                          "line" => 14,
+                          "character" => 4
+                        }
+                      },
+                      "uri" => ^uri
+                    },
+                    500
+    end
+  end
 end