Optimize more traversals

Author: josevalim

lib/elixir/lib/module/types/expr.ex

@@ -78,14 +78,35 @@ defmodule Module.Types.Expr do
     {prefix, suffix} = unpack_list(list, [])
     {prefix, context} = Enum.map_reduce(prefix, context, &of_expr(&1, stack, &2))
     {suffix, context} = of_expr(suffix, stack, context)
-    {non_empty_list(Enum.reduce(prefix, &union/2), suffix), context}
+
+    if stack.mode == :traversal do
+      {dynamic(), context}
+    else
+      {non_empty_list(Enum.reduce(prefix, &union/2), suffix), context}
+    end
   end
 
   # {left, right}
   def of_expr({left, right}, stack, context) do
     {left, context} = of_expr(left, stack, context)
     {right, context} = of_expr(right, stack, context)
-    {tuple([left, right]), context}
+
+    if stack.mode == :traversal do
+      {dynamic(), context}
+    else
+      {tuple([left, right]), context}
+    end
+  end
+
+  # {...}
+  def of_expr({:{}, _meta, exprs}, stack, context) do
+    {types, context} = Enum.map_reduce(exprs, context, &of_expr(&1, stack, &2))
+
+    if stack.mode == :traversal do
+      {dynamic(), context}
+    else
+      {tuple(types), context}
+    end
   end
 
   # <<...>>>
@@ -103,12 +124,6 @@ defmodule Module.Types.Expr do
     {@stacktrace, context}
   end
 
-  # {...}
-  def of_expr({:{}, _meta, exprs}, stack, context) do
-    {types, context} = Enum.map_reduce(exprs, context, &of_expr(&1, stack, &2))
-    {tuple(types), context}
-  end
-
   # left = right
   def of_expr({:=, _, [left_expr, right_expr]} = expr, stack, context) do
     {left_expr, right_expr} = repack_match(left_expr, right_expr)

lib/elixir/lib/module/types/of.ex

@@ -115,6 +115,17 @@ defmodule Module.Types.Of do
   @doc """
   Builds permutation of maps according to the given keys.
   """
+  def permutate_map(pairs, %{mode: :traversal} = stack, context, of_fun, _of_map) do
+    context =
+      Enum.reduce(pairs, context, fn {key, value}, context ->
+        {_, context} = of_fun.(key, stack, context)
+        {_, context} = of_fun.(value, stack, context)
+        context
+      end)
+
+    {dynamic(), context}
+  end
+
   def permutate_map(pairs, stack, context, of_fun, of_map) do
     {dynamic?, fallback, single, multiple, assert, context} =
       Enum.reduce(pairs, {false, none(), [], [], [], context}, fn