ignore no-paren, no-body function heads. closes #185

CHANGELOG.md

@@ -14,6 +14,7 @@ they can and will change without that change being reflected in Styler's semanti
 
 ### Fixes
 
+* don't blow up on `def function_head_with_no_body_nor_parens` (#185, h/t @ypconstante)
 * fix `with` arrow replacement + redundant body removal creating invalid statements (#184, h/t @JesseHerrick)
 * allow Kernel unary `!` and `not` as valid pipe starts (#183, h/t @nherzing)
 

lib/style/defs.ex

@@ -52,13 +52,20 @@ defmodule Styler.Style.Defs do
     first_line = meta[:line]
     last_line = head_meta[:closing][:line]
 
-    if first_line == last_line do
+    cond do
+      # weird `def fun`, nothing else
+      is_nil(last_line) ->
+        {:skip, zipper, ctx}
+
       # Already collapsed
-      {:skip, zipper, ctx}
-    else
-      comments = Style.displace_comments(ctx.comments, first_line..last_line)
-      node = {def, meta, [Style.set_line(head, meta[:line])]}
-      {:skip, Zipper.replace(zipper, node), %{ctx | comments: comments}}
+      first_line == last_line ->
+        {:skip, zipper, ctx}
+
+      # I just felt like this clause deserved a comment too. It's my favorite one
+      true ->
+        comments = Style.displace_comments(ctx.comments, first_line..last_line)
+        node = {def, meta, [Style.set_line(head, first_line)]}
+        {:skip, Zipper.replace(zipper, node), %{ctx | comments: comments}}
     end
   end
 

test/style/defs_test.exs

@@ -98,6 +98,8 @@ defmodule Styler.Style.DefsTest do
     end
 
     test "no body" do
+      assert_style "def no_body_nor_parens_yikes!"
+
       assert_style(
         """
         # Top comment