add tests for + - followed by comment edge cases

Language/SQL/SimpleSQL/Lex.lhs

@@ -370,7 +370,6 @@ which allows the last character of a multi character symbol to be + or
 >    -- special case for parsing a single + or - symbol
 >    singlePlusMinus = try $ do
 >      c <- oneOf "+-"
->      -- todo: make sure it deals with e.g. --- +-- +/* -/*?
 >      notFollowedBy $ oneOf allOpSymbols
 >      return [c]
 

tools/Language/SQL/SimpleSQL/LexerTests.lhs

@@ -284,7 +284,9 @@ the + or -.
 >      [LexerTest postgres s t | (s,t) <- postgresLexerTable]
 >     ,Group "adhoc lexer tests" $
 >      [LexerTest postgres s t
->      | (s,t) <- edgeCaseCommentOps ++ edgeCasePlusMinusOps ]
+>      | (s,t) <- edgeCaseCommentOps
+>                 ++ edgeCasePlusMinusOps
+>                 ++ edgeCasePlusMinusComments]
 >     ]
 >  where
 >    edgeCaseCommentOps = concat
@@ -298,6 +300,12 @@ the + or -.
 >        , (x ++ "-", [Symbol x, Symbol "-"]) ]
 >      | x <- somePostgresOpsWhichWontAddTrailingPlusMinus 2
 >      ]
+>    edgeCasePlusMinusComments =
+>      [("---", [LineComment "---"])
+>      ,("+--", [Symbol "+", LineComment "--"])
+>      ,("-/**/", [Symbol "-", BlockComment "/**/"])
+>      ,("+/**/", [Symbol "+", BlockComment "/**/"])
+>      ]
 
 
 > combos :: [a] -> Int -> [[a]]