fix(completions): imports inside blocks that generate functions (#423)

The `test/2` macro is an example of this

Closes #420

Author: mhanberg

Diff for: lib/next_ls.ex

@@ -646,6 +646,7 @@ defmodule NextLS do
               |> then(fn
                 {:ok, ast} -> ast
                 {:error, ast, _} -> ast
+                {:error, :no_fuel_remaining} -> nil
               end)
 
             {:ok, {_, _, _, macro_env}} = Runtime.expand(runtime, ast, Path.basename(uri))

Diff for: priv/monkey/_next_ls_private_compiler.ex

@@ -1217,52 +1217,46 @@ if Version.match?(System.version(), ">= 1.17.0-dev") do
       {arg, state, env} = expand(arg, state, env)
       {opts, state, env} = expand_directive_opts(opts, state, env)
 
-      case arg do
-        {:__aliases__, _, _} ->
-          # An actual compiler would raise if the alias fails.
-          case Macro.Env.define_alias(env, meta, arg, [trace: false] ++ opts) do
-            {:ok, env} -> {arg, state, env}
-            {:error, _} -> {arg, state, env}
-          end
-
-        _ ->
-          {node, state, env}
+      if is_atom(arg) do
+        # An actual compiler would raise if the alias fails.
+        case Macro.Env.define_alias(env, meta, arg, [trace: false] ++ opts) do
+          {:ok, env} -> {arg, state, env}
+          {:error, _} -> {arg, state, env}
+        end
+      else
+        {node, state, env}
       end
     end
 
     defp expand({:require, meta, [arg, opts]} = node, state, env) do
       {arg, state, env} = expand(arg, state, env)
       {opts, state, env} = expand_directive_opts(opts, state, env)
 
-      case arg do
-        {:__aliases__, _, _} ->
-          # An actual compiler would raise if the module is not defined or if the require fails.
-          case Macro.Env.define_require(env, meta, arg, [trace: false] ++ opts) do
-            {:ok, env} -> {arg, state, env}
-            {:error, _} -> {arg, state, env}
-          end
-
-        _ ->
-          {node, state, env}
+      if is_atom(arg) do
+        # An actual compiler would raise if the module is not defined or if the require fails.
+        case Macro.Env.define_require(env, meta, arg, [trace: false] ++ opts) do
+          {:ok, env} -> {arg, state, env}
+          {:error, _} -> {arg, state, env}
+        end
+      else
+        {node, state, env}
       end
     end
 
     defp expand({:import, meta, [arg, opts]} = node, state, env) do
       {arg, state, env} = expand(arg, state, env)
       {opts, state, env} = expand_directive_opts(opts, state, env)
 
-      case arg do
-        {:__aliases__, _, _} ->
-          # An actual compiler would raise if the module is not defined or if the import fails.
-          with true <- is_atom(arg) and Code.ensure_loaded?(arg),
-               {:ok, env} <- Macro.Env.define_import(env, meta, arg, [trace: false] ++ opts) do
-            {arg, state, env}
-          else
-            _ -> {arg, state, env}
-          end
-
-        _ ->
-          {node, state, env}
+      if is_atom(arg) do
+        # An actual compiler would raise if the module is not defined or if the import fails.
+        with true <- is_atom(arg) and Code.ensure_loaded?(arg),
+             {:ok, env} <- Macro.Env.define_import(env, meta, arg, [trace: false] ++ opts) do
+          {arg, state, env}
+        else
+          _ -> {arg, state, env}
+        end
+      else
+        {node, state, env}
       end
     end
 
@@ -1444,6 +1438,20 @@ if Version.match?(System.version(), ">= 1.17.0-dev") do
       {Enum.reverse(blocks), put_in(state.functions, functions), env}
     end
 
+    defp expand_macro(_meta, Kernel, type, [{_name, _, params}, blocks], _callback, state, env)
+         when type in [:def, :defp] and is_list(params) and is_list(blocks) do
+      {blocks, state} =
+        for {type, block} <- blocks, reduce: {[], state} do
+          {acc, state} ->
+            {res, state, _env} = expand(block, state, env)
+            {[{type, res} | acc], state}
+        end
+
+      arity = length(List.wrap(params))
+
+      {Enum.reverse(blocks), state, env}
+    end
+
     defp expand_macro(meta, Kernel, :@, [{name, _, p}] = args, callback, state, env) when is_list(p) do
       state = update_in(state.attrs, &[to_string(name) | &1])
       expand_macro_callback(meta, Kernel, :@, args, callback, state, env)
@@ -1527,7 +1535,7 @@ if Version.match?(System.version(), ">= 1.17.0-dev") do
       {Enum.reverse(acc), state, env}
     end
 
-    defp expand_list([h | t], state, env, acc) do
+    defp expand_list([h | t] = list, state, env, acc) do
       {h, state, env} = expand(h, state, env)
       expand_list(t, state, env, [h | acc])
     end

Diff for: test/next_ls/completions_test.exs

@@ -5,6 +5,20 @@ defmodule NextLS.CompletionsTest do
   import GenLSP.Test
   import NextLS.Support.Utils
 
+  defmacrop assert_match({:in, _, [left, right]}) do
+    quote do
+      assert Enum.any?(unquote(right), fn x ->
+               match?(unquote(left), x)
+             end),
+             """
+             failed to find a match inside of list
+
+             left: #{unquote(Macro.to_string(left))}
+             right: #{inspect(unquote(right), pretty: true)}
+             """
+    end
+  end
+
   @moduletag tmp_dir: true, root_paths: ["my_proj"]
 
   setup %{tmp_dir: tmp_dir} do
@@ -34,7 +48,7 @@ defmodule NextLS.CompletionsTest do
     baz = Path.join(cwd, "my_proj/lib/baz.ex")
 
     File.write!(baz, """
-    defmodule Foo.Bar.Baz do
+    defmodule Foo.Bing.Baz do
       def run() do
         :ok
       end
@@ -361,12 +375,47 @@ defmodule NextLS.CompletionsTest do
     ]
   end
 
+  test "aliases in document", %{client: client, foo: foo} do
+    uri = uri(foo)
+
+    did_open(client, foo, """
+    defmodule Foo do
+      alias Foo.Bing
+
+      def run() do
+        B
+      end
+    end
+    """)
+
+    request client, %{
+      method: "textDocument/completion",
+      id: 2,
+      jsonrpc: "2.0",
+      params: %{
+        textDocument: %{
+          uri: uri
+        },
+        position: %{
+          line: 4,
+          character: 5
+        }
+      }
+    }
+
+    assert_result 2, results
+
+    assert_match(
+      %{"data" => _, "documentation" => _, "insertText" => "Bing", "kind" => 9, "label" => "Bing"} in results
+    )
+  end
+
   test "inside alias special form", %{client: client, foo: foo} do
     uri = uri(foo)
 
     did_open(client, foo, """
     defmodule Foo do
-      alias Foo.Bar.
+      alias Foo.Bing.
 
       def run() do
         :ok
@@ -390,7 +439,47 @@ defmodule NextLS.CompletionsTest do
     }
 
     assert_result 2, [
-      %{"data" => _, "documentation" => _, "insertText" => "Baz", "kind" => 9, "label" => "Baz"}
+      %{"data" => _, "documentation" => _, "insertText" => "Bing", "kind" => 9, "label" => "Bing"}
     ]
   end
+
+  test "import functions appear", %{client: client, foo: foo} do
+    uri = uri(foo)
+
+    did_open(client, foo, """
+    defmodule Foo do
+      use ExUnit.Case
+      import ExUnit.CaptureLog
+
+      test "foo" do
+        cap
+      end
+    end
+    """)
+
+    request client, %{
+      method: "textDocument/completion",
+      id: 2,
+      jsonrpc: "2.0",
+      params: %{
+        textDocument: %{
+          uri: uri
+        },
+        position: %{
+          line: 5,
+          character: 7
+        }
+      }
+    }
+
+    assert_result 2, results
+
+    assert_match(
+      %{"data" => _, "documentation" => _, "insertText" => "capture_log", "kind" => 3, "label" => "capture_log/1"} in results
+    )
+
+    assert_match(
+      %{"data" => _, "documentation" => _, "insertText" => "capture_log", "kind" => 3, "label" => "capture_log/2"} in results
+    )
+  end
 end