 
   test "group doc" do
     # Consistent with definitions
-    assert group(glue("a", "b")) ==
-           {:doc_group, {:doc_cons, "a", concat(break(), "b")}}
+    assert group("ab") == {:doc_group, "ab"}
     assert group(empty()) == {:doc_group, empty()}
 
     # Consistent formatting

    # Consistent formatting
    assert render(nest("a", 1), 80) == "a"
    assert render(nest(glue("a", "b"), 1), 2) == "a\n b"
  end

  test "color doc" do

    assert_raise FunctionClauseError, fn -> glue("a", 42, "b") end
  end

  test "flex glue doc" do
    # Consistent with definitions
    assert flex_glue("a", "->", "b") ==
           {:doc_cons, "a", {:doc_cons, {:doc_break, "->", :flex}, "b"}}
    assert flex_glue("a", "b") == flex_glue("a", " ", "b")

    # Wrong argument type
    assert_raise FunctionClauseError, fn -> flex_glue("a", 42, "b") end
  end

  test "binary doc" do
    assert render("_", 80) == "_"
  end

  test "string doc" do
    # Consistent with definitions
    assert string("ólá") == {:doc_string, "ólá", 3}

    # Counts graphemes
    doc = glue(string("olá"), " ", string("mundo"))
    assert render(doc, 9) == "olá mundo"
  end

  test "space doc" do
    # Consistent with definitions
    assert space("a", "b") ==
           {:doc_cons, "a", {:doc_cons, " ", "b"}}
  end

  test "always nest doc" do
    # Consistent with definitions
    assert nest(empty(), 1) == {:doc_nest, empty(), 1, :always}
    assert nest(empty(), 0) == :doc_nil
