put single line yaml info on one line

tests/TAP.idr

@@ -20,13 +20,19 @@ record TestBase where
   run   : IO Result
 
 
+private
+toLines1 : (String, String) -> List String
+toLines1 (k, v) =
+  let vs = lines v in
+  if length vs == 1
+     then ["\{k}: \{v}"]
+     else "\{k}: |" :: map (indent 2) vs
+
 private
 toLines : Info -> List String
 toLines [] = []
-toLines xs =
-  "---" ::
-  concatMap (\(k, v) => "\{k}: |" :: map (indent 2) (lines v)) xs
-  <+> ["..."]
+toLines xs = "---" :: concatMap toLines1 xs <+> ["..."]
+
 
 public export interface ToInfo e where toInfo : e -> Info