find elixir modules that require adding an alias

lib/elixir_sense.ex

@@ -202,8 +202,8 @@ defmodule ElixirSense do
         name: "insert_at", metadata: %{}, snippet: nil, visibility: :public,
         spec: "@spec insert_at(list, integer, any) :: list", summary: "Returns a list with `value` inserted at the specified `index`."}]
   """
-  @spec suggestions(String.t(), pos_integer, pos_integer) :: [Suggestion.suggestion()]
-  def suggestions(buffer, line, column) do
+  @spec suggestions(String.t(), pos_integer, pos_integer, keyword()) :: [Suggestion.suggestion()]
+  def suggestions(buffer, line, column, opts \\ []) do
     hint = Source.prefix(buffer, line, column)
     buffer_file_metadata = Parser.parse_string(buffer, true, true, line)
     {text_before, text_after} = Source.split_at(buffer, line, column)
@@ -220,7 +220,7 @@ defmodule ElixirSense do
       at_module_body?: Metadata.at_module_body?(buffer_file_metadata, env)
     }
 
-    Suggestion.find(hint, env, buffer_file_metadata, cursor_context, module_store)
+    Suggestion.find(hint, env, buffer_file_metadata, cursor_context, module_store, opts)
   end
 
   @doc """

lib/elixir_sense/core/metadata.ex

@@ -17,7 +17,9 @@ defmodule ElixirSense.Core.Metadata do
           types: State.types_t(),
           specs: State.specs_t(),
           structs: State.structs_t(),
-          error: nil | term
+          error: nil | term,
+          first_alias_positions: map(),
+          moduledoc_positions: map()
         }
 
   defstruct source: "",
@@ -28,7 +30,9 @@ defmodule ElixirSense.Core.Metadata do
             types: %{},
             specs: %{},
             structs: %{},
-            error: nil
+            error: nil,
+            first_alias_positions: %{},
+            moduledoc_positions: %{}
 
   @type signature_t :: %{
           name: String.t(),
@@ -58,6 +62,33 @@ defmodule ElixirSense.Core.Metadata do
     end
   end
 
+  def get_position_to_insert_alias(%__MODULE__{} = metadata, line) do
+    env = get_env(metadata, line)
+    module = env.module
+
+    cond do
+      Map.has_key?(metadata.first_alias_positions, module) ->
+        Map.get(metadata.first_alias_positions, module)
+
+      Map.has_key?(metadata.moduledoc_positions, module) ->
+        Map.get(metadata.moduledoc_positions, module)
+
+      true ->
+        mod_info = Map.get(metadata.mods_funs_to_positions, {env.module, nil, nil})
+
+        case mod_info do
+          %State.ModFunInfo{positions: [{line, column}]} ->
+            # Hacky :shrug
+            line_offset = 1
+            column_offset = -8
+            {line + line_offset, column + column_offset}
+
+          _ ->
+            nil
+        end
+    end
+  end
+
   def get_calls(%__MODULE__{} = metadata, line) do
     case Map.get(metadata.calls, line) do
       nil -> []

lib/elixir_sense/core/metadata_builder.ex

@@ -619,6 +619,9 @@ defmodule ElixirSense.Core.MetadataBuilder do
           {get_binding_type(state, param), true}
       end
 
+    state =
+      add_moduledoc_positions(state, [line: line, column: column], [{name, meta, params}], line)
+
     new_ast = {:@, meta_attr, [{name, add_no_call(meta), params}]}
     pre_module_attribute(new_ast, state, {line, column}, name, type, is_definition)
   end
@@ -704,46 +707,50 @@ defmodule ElixirSense.Core.MetadataBuilder do
 
   # alias with `as` option
   defp pre(
-         {:alias, [line: line, column: _column],
+         {:alias, [line: line, column: column],
           [{_, _, module_expression = [_ | _]}, [as: alias_expression]]} = ast,
          state
        ) do
     module = concat_module_expression(state, module_expression)
     alias_tuple = alias_tuple(module, alias_expression)
+    state = add_first_alias_positions(state, line, column)
     pre_alias(ast, state, line, alias_tuple)
   end
 
   # alias for submodule of __MODULE__ with `as` option
   defp pre(
-         {:alias, [line: line, column: _column], [{:__MODULE__, _, nil}, [as: alias_expression]]} =
+         {:alias, [line: line, column: column], [{:__MODULE__, _, nil}, [as: alias_expression]]} =
            ast,
          state
        ) do
     module = get_current_module(state)
     alias_tuple = alias_tuple(module, alias_expression)
+    state = add_first_alias_positions(state, line, column)
     pre_alias(ast, state, line, alias_tuple)
   end
 
   # alias atom module with `as` option
-  defp pre({:alias, [line: line, column: _column], [mod, [as: alias_expression]]} = ast, state)
+  defp pre({:alias, [line: line, column: column], [mod, [as: alias_expression]]} = ast, state)
        when is_atom(mod) do
     alias_tuple = alias_tuple(mod, alias_expression)
+    state = add_first_alias_positions(state, line, column)
     pre_alias(ast, state, line, alias_tuple)
   end
 
   # alias
   defp pre(
-         {:alias, [line: line, column: _column],
+         {:alias, [line: line, column: column],
           [{:__aliases__, _, module_expression = [_ | _]}, _opts]} = ast,
          state
        ) do
     module = concat_module_expression(state, module_expression)
     alias_tuple = {Module.concat([List.last(module_expression)]), module}
+    state = add_first_alias_positions(state, line, column)
     pre_alias(ast, state, line, alias_tuple)
   end
 
   # alias atom module
-  defp pre({:alias, [line: line, column: _column], [mod, _opts]} = ast, state)
+  defp pre({:alias, [line: line, column: column], [mod, _opts]} = ast, state)
        when is_atom(mod) do
     alias_tuple =
       if Introspection.elixir_module?(mod) do
@@ -752,6 +759,7 @@ defmodule ElixirSense.Core.MetadataBuilder do
         {mod, mod}
       end
 
+    state = add_first_alias_positions(state, line, column)
     pre_alias(ast, state, line, alias_tuple)
   end
 

lib/elixir_sense/core/parser.ex

@@ -94,7 +94,9 @@ defmodule ElixirSense.Core.Parser do
       mods_funs_to_positions: acc.mods_funs_to_positions,
       lines_to_env: acc.lines_to_env,
       vars_info_per_scope_id: acc.vars_info_per_scope_id,
-      calls: acc.calls
+      calls: acc.calls,
+      first_alias_positions: acc.first_alias_positions,
+      moduledoc_positions: acc.moduledoc_positions
     }
   end
 

lib/elixir_sense/core/state.ex

@@ -52,6 +52,8 @@ defmodule ElixirSense.Core.State do
           calls: calls_t,
           structs: structs_t,
           types: types_t,
+          first_alias_positions: map(),
+          moduledoc_positions: map(),
           # TODO
           binding_context: list
         }
@@ -76,7 +78,9 @@ defmodule ElixirSense.Core.State do
             calls: %{},
             structs: %{},
             types: %{},
-            binding_context: []
+            binding_context: [],
+            first_alias_positions: %{},
+            moduledoc_positions: %{}
 
   defmodule Env do
     @moduledoc """
@@ -303,6 +307,75 @@ defmodule ElixirSense.Core.State do
     %__MODULE__{state | lines_to_env: Map.put(state.lines_to_env, line, env)}
   end
 
+  def add_moduledoc_positions(
+        %__MODULE__{} = state,
+        [line: line, column: column],
+        [{:moduledoc, _meta, [here_doc]}],
+        line
+      )
+      when is_integer(line) and is_binary(here_doc) do
+    module_name = module_name(state)
+
+    new_line_count = here_doc |> String.split("\n") |> Enum.count()
+    line_to_insert_alias = new_line_count + line + 1
+
+    %__MODULE__{
+      state
+      | moduledoc_positions:
+          Map.put(state.moduledoc_positions, module_name, {line_to_insert_alias, column})
+    }
+  end
+
+  def add_moduledoc_positions(
+        %__MODULE__{} = state,
+        [line: line, column: column],
+        [{:moduledoc, _meta, [params]}],
+        line
+      )
+      when is_integer(line) and is_boolean(params) do
+    module_name = module_name(state)
+
+    line_to_insert_alias = line + 1
+
+    %__MODULE__{
+      state
+      | moduledoc_positions:
+          Map.put(state.moduledoc_positions, module_name, {line_to_insert_alias, column})
+    }
+  end
+
+  def add_moduledoc_positions(state, _, _, _), do: state
+
+  def add_first_alias_positions(%__MODULE__{} = state, line, column)
+      when is_integer(line) and is_integer(column) do
+    current_scope = hd(hd(state.scopes))
+
+    is_module? = is_atom(current_scope)
+
+    if is_module? do
+      module_name = module_name(state)
+
+      %__MODULE__{
+        state
+        | first_alias_positions:
+            Map.put_new(state.first_alias_positions, module_name, {line, column})
+      }
+    else
+      state
+    end
+  end
+
+  defp module_name(state) do
+    hd(state.scopes)
+    |> Enum.reverse()
+    |> after_elixir_prefix()
+    |> Enum.filter(&is_atom/1)
+    |> Module.concat()
+  end
+
+  defp after_elixir_prefix([Elixir | rest]), do: rest
+  defp after_elixir_prefix(rest), do: rest
+
   def add_call_to_line(%__MODULE__{} = state, {mod, func, arity}, {line, _column} = position) do
     call = %CallInfo{mod: mod, func: func, arity: arity, position: position}
 

lib/elixir_sense/providers/suggestion.ex

@@ -88,7 +88,7 @@ defmodule ElixirSense.Providers.Suggestion do
     overridable: &Reducers.Overridable.add_overridable/5,
     param_options: &Reducers.Params.add_options/5,
     typespecs: &Reducers.TypeSpecs.add_types/5,
-    populate_common: &Reducers.Common.populate/5,
+    populate_common: &Reducers.Common.populate/6,
     variables: &Reducers.Common.add_variables/5,
     modules: &Reducers.Common.add_modules/5,
     functions: &Reducers.Common.add_functions/5,
@@ -99,12 +99,14 @@ defmodule ElixirSense.Providers.Suggestion do
     bitstring_options: &Reducers.Bitstring.add_bitstring_options/5
   ]
 
+  @add_opts_for [:populate_common]
+
   @doc """
   Finds all suggestions for a hint based on context information.
   """
-  @spec find(String.t(), State.Env.t(), Metadata.t(), cursor_context, ModuleStore.t()) ::
+  @spec find(String.t(), State.Env.t(), Metadata.t(), cursor_context, ModuleStore.t(), keyword()) ::
           [suggestion()]
-  def find(hint, env, buffer_metadata, cursor_context, module_store) do
+  def find(hint, env, buffer_metadata, cursor_context, module_store, opts \\ []) do
     plugins = module_store.by_behaviour[ElixirSense.Plugin] || []
 
     reducers =
@@ -114,6 +116,7 @@ defmodule ElixirSense.Providers.Suggestion do
         {module, &module.reduce/5}
       end)
       |> Enum.concat(@reducers)
+      |> maybe_add_opts(opts)
 
     context =
       plugins
@@ -139,4 +142,18 @@ defmodule ElixirSense.Providers.Suggestion do
       |> Enum.reduce(item, fn module, item -> module.decorate(item) end)
     end
   end
+
+  defp maybe_add_opts(reducers, opts) do
+    Enum.map(reducers, fn {name, reducer} ->
+      if name in @add_opts_for do
+        {name, reducer_with_opts(reducer, opts)}
+      else
+        {name, reducer}
+      end
+    end)
+  end
+
+  defp reducer_with_opts(fun, opts) do
+    fn a, b, c, d, e -> fun.(a, b, c, d, e, opts) end
+  end
 end