Use algebra concat instead of binary concat

Author: josevalim

lib/elixir/lib/inspect.ex

@@ -157,7 +157,7 @@ defimpl Inspect, for: BitString do
   defp each_bit(bitstring, _counter, opts) do
     size = bit_size(bitstring)
     <<h::size(size)>> = bitstring
-    Inspect.Integer.inspect(h, opts) <> "::size(" <> Integer.to_string(size) <> ")"
+    concat(Inspect.Integer.inspect(h, opts), "::size(" <> Integer.to_string(size) <> ")")
   end
 
   @compile {:inline, decrement: 1}

lib/elixir/test/elixir/inspect_test.exs

@@ -108,6 +108,10 @@ defmodule Inspect.BitStringTest do
 
   test "bitstring" do
     assert inspect(<<1::12-integer-signed>>) == "<<0, 1::size(4)>>"
+
+    assert inspect(<<1::12-integer-signed>>, syntax_colors: [number: :blue]) ==
+             "<<\e[34m0\e[0m, \e[34m1\e[0m::size(4)>>"
+
     assert inspect(<<1, 2, 3, 4, 5>>, pretty: true, width: 10) == "<<1, 2, 3,\n  4, 5>>"
   end