Fix interaction of do-block with ExprWithTySig

data/15-regressions.blt

@@ -1101,3 +1101,10 @@ func = do
                            }
           )
           anotherArgument
+
+#test yet another invalid do-block operator alignment
+func = do
+  it "some long description does not matter" $ do
+    some long function invocation (plus a paren + ed operator expression)
+      `shouldReturn` all ((==) True)
+      :: IO ()

source/library/Language/Haskell/Brittany/Internal/ToBriDoc/Expr.hs

@@ -850,7 +850,11 @@ layoutExpr lexpr@(L _ expr) = do
     ExprWithTySig _ exp1 (HsWC _ typ1) -> do
       expDoc <- shareDoc $ callLayouter layout_expr exp1
       typDoc <- shareDoc $ callLayouter layout_sigType typ1
-      docSeq [appSep expDoc, appSep $ docLit $ Text.pack "::", typDoc]
+      docAlt
+        [ docForceSingleline
+          $ docSeq [appSep expDoc, appSep $ docLitS "::", typDoc]
+        , docPar expDoc (docSeq [docLitS "::", docSeparator, typDoc])
+        ]
     ArithSeq _ Nothing info -> case info of
       From e1 -> do
         e1Doc <- shareDoc $ layoutExpr e1