Improve completion (#756)

* Don't show variable value in intellisense

* Don't complete quoted atoms

lib/livebook/intellisense.ex

@@ -127,21 +127,21 @@ defmodule Livebook.Intellisense do
 
   defp include_in_completion?(_), do: true
 
-  defp format_completion_item({:variable, name, value}),
+  defp format_completion_item({:variable, name, _value}),
     do: %{
       label: name,
       kind: :variable,
       detail: "variable",
-      documentation: value_snippet(value, @line_length),
+      documentation: nil,
       insert_text: name
     }
 
-  defp format_completion_item({:map_field, name, value}),
+  defp format_completion_item({:map_field, name, _value}),
     do: %{
       label: name,
       kind: :field,
       detail: "field",
-      documentation: value_snippet(value, @line_length),
+      documentation: nil,
       insert_text: name
     }
 
@@ -336,18 +336,9 @@ defmodule Livebook.Intellisense do
     end
   end
 
-  defp format_details_item({:variable, name, value}) do
+  defp format_details_item({:variable, name, _value}), do: code(name)
-    join_with_divider([
-      code(name),
-      value_snippet(value, @extended_line_length)
-    ])
-  end
 
-  defp format_details_item({:map_field, _name, value}) do
+  defp format_details_item({:map_field, name, _value}), do: code(name)
-    join_with_divider([
-      value_snippet(value, @extended_line_length)
-    ])
-  end
 
   defp format_details_item({:module, _module, display_name, documentation}) do
     join_with_divider([
@@ -403,14 +394,6 @@ defmodule Livebook.Intellisense do
     """
   end
 
-  defp value_snippet(value, line_length) do
-    """
-    ```
-    #{inspect(value, pretty: true, width: line_length)}
-    ```\
-    """
-  end
-
   defp format_signatures([], _module), do: nil
 
   defp format_signatures(signatures, module) do

lib/livebook/intellisense/identifier_matcher.ex

@@ -341,7 +341,7 @@ defmodule Livebook.Intellisense.IdentifierMatcher do
   defp valid_alias_rest?(rest), do: valid_alias_piece?(rest)
 
   defp usable_as_unquoted_module?(mod) do
-    Code.Identifier.classify(mod) != :other
+    macro_classify_atom(mod) in [:identifier, :unquoted]
   end
 
   defp get_matching_modules(hint, ctx) do
@@ -484,4 +484,70 @@ defmodule Livebook.Intellisense.IdentifierMatcher do
         ctx.matcher.(name, hint),
         do: {:module_attribute, name, {"text/markdown", info.doc}}
   end
+
+  # ---
+
+  # TODO use Macro.classify_atom/1 on Elixir 1.14
+
+  def macro_classify_atom(atom) do
+    case macro_inner_classify(atom) do
+      :alias -> :alias
+      :identifier -> :identifier
+      type when type in [:unquoted_operator, :not_callable] -> :unquoted
+      _ -> :quoted
+    end
+  end
+
+  defp macro_inner_classify(atom) when is_atom(atom) do
+    cond do
+      atom in [:%, :%{}, :{}, :<<>>, :..., :.., :., :"..//", :->] ->
+        :not_callable
+
+      atom in [:"::"] ->
+        :quoted_operator
+
+      Macro.operator?(atom, 1) or Macro.operator?(atom, 2) ->
+        :unquoted_operator
+
+      true ->
+        charlist = Atom.to_charlist(atom)
+
+        if macro_valid_alias?(charlist) do
+          :alias
+        else
+          case :elixir_config.identifier_tokenizer().tokenize(charlist) do
+            {kind, _acc, [], _, _, special} ->
+              if kind == :identifier and not :lists.member(?@, special) do
+                :identifier
+              else
+                :not_callable
+              end
+
+            _ ->
+              :other
+          end
+        end
+    end
+  end
+
+  defp macro_valid_alias?('Elixir' ++ rest), do: macro_valid_alias_piece?(rest)
+  defp macro_valid_alias?(_other), do: false
+
+  defp macro_valid_alias_piece?([?., char | rest]) when char >= ?A and char <= ?Z,
+    do: macro_valid_alias_piece?(macro_trim_leading_while_valid_identifier(rest))
+
+  defp macro_valid_alias_piece?([]), do: true
+  defp macro_valid_alias_piece?(_other), do: false
+
+  defp macro_trim_leading_while_valid_identifier([char | rest])
+       when char >= ?a and char <= ?z
+       when char >= ?A and char <= ?Z
+       when char >= ?0 and char <= ?9
+       when char == ?_ do
+    macro_trim_leading_while_valid_identifier(rest)
+  end
+
+  defp macro_trim_leading_while_valid_identifier(other) do
+    other
+  end
 end

test/livebook/intellisense_test.exs

@@ -112,6 +112,13 @@ defmodule Livebook.IntellisenseTest do
       assert lists_item in Intellisense.get_completion_items("  :", binding, env)
     end
 
+    @tag :erl_docs
+    test "Erlang completion doesn't include quoted atoms" do
+      {binding, env} = eval(do: nil)
+
+      assert [] = Intellisense.get_completion_items(~s{:Elixir}, binding, env)
+    end
+
     @tag :erl_docs
     test "Erlang module completion with 'in' operator in spec" do
       {binding, env} = eval(do: nil)
@@ -589,21 +596,21 @@ defmodule Livebook.IntellisenseTest do
                  label: "bar_1",
                  kind: :field,
                  detail: "field",
-                 documentation: ~s{```\n~r/pattern/\n```},
+                 documentation: nil,
                  insert_text: "bar_1"
                },
                %{
                  label: "bar_2",
                  kind: :field,
                  detail: "field",
-                 documentation: ~s{```\ntrue\n```},
+                 documentation: nil,
                  insert_text: "bar_2"
                },
                %{
                  label: "foo",
                  kind: :field,
                  detail: "field",
-                 documentation: ~s{```\n1\n```},
+                 documentation: nil,
                  insert_text: "foo"
                }
              ] = Intellisense.get_completion_items("map.", binding, env)
@@ -613,7 +620,7 @@ defmodule Livebook.IntellisenseTest do
                  label: "foo",
                  kind: :field,
                  detail: "field",
-                 documentation: ~s{```\n1\n```},
+                 documentation: nil,
                  insert_text: "foo"
                }
              ] = Intellisense.get_completion_items("map.f", binding, env)
@@ -639,18 +646,7 @@ defmodule Livebook.IntellisenseTest do
                  label: "nested",
                  kind: :field,
                  detail: "field",
-                 documentation: """
+                 documentation: nil,
-                 ```
-                 %{
-                   deeply: %{
-                     bar_1: 23,
-                     bar_2: 14,
-                     foo: 1,
-                     mod: System
-                   }
-                 }
-                 ```\
-                 """,
                  insert_text: "nested"
                }
              ] = Intellisense.get_completion_items("map.nest", binding, env)
@@ -660,7 +656,7 @@ defmodule Livebook.IntellisenseTest do
                  label: "foo",
                  kind: :field,
                  detail: "field",
-                 documentation: ~s{```\n1\n```},
+                 documentation: nil,
                  insert_text: "foo"
                }
              ] = Intellisense.get_completion_items("map.nested.deeply.f", binding, env)
@@ -787,7 +783,7 @@ defmodule Livebook.IntellisenseTest do
                  label: "numbats",
                  kind: :variable,
                  detail: "variable",
-                 documentation: ~s{```\n["numbat", "numbat"]\n```},
+                 documentation: nil,
                  insert_text: "numbats"
                }
              ] = Intellisense.get_completion_items("numba", binding, env)
@@ -797,14 +793,14 @@ defmodule Livebook.IntellisenseTest do
                  label: "numbats",
                  kind: :variable,
                  detail: "variable",
-                 documentation: ~s{```\n["numbat", "numbat"]\n```},
+                 documentation: nil,
                  insert_text: "numbats"
                },
                %{
                  label: "number",
                  kind: :variable,
                  detail: "variable",
-                 documentation: ~s{```\n3\n```},
+                 documentation: nil,
                  insert_text: "number"
                }
              ] = Intellisense.get_completion_items("num", binding, env)
@@ -814,7 +810,7 @@ defmodule Livebook.IntellisenseTest do
                  label: "nothing",
                  kind: :variable,
                  detail: "variable",
-                 documentation: ~s{```\nnil\n```},
+                 documentation: nil,
                  insert_text: "nothing"
                },
                %{label: "node/0"},