Add support for comments.

- Add support for multiline and end of line comments
- Spaces do not need to be optional (it parses zero or more spaces)
- Add spacesOrComment for parsing comments around the expressions

src/NpgsqlFSharpParser/Parser.fs

@@ -86,20 +86,22 @@ let manyCharsBetween popen pclose pchar = popen >>? manyCharsTill pchar pclose
 // Parses any string between popen and pclose
 let anyStringBetween popen pclose = manyCharsBetween popen pclose anyChar
 
+let skipBetween popen pclose = popen >>? skipManyTill skipAnyChar pclose
+
 // Cannot be a reserved keyword.
 let unquotedIdentifier : Parser<string, unit> =
     let isIdentifierFirstChar token = isLetter token
     let isIdentifierChar token = isLetter token || isDigit token || token = '_'
 
-    many1Satisfy2L isIdentifierFirstChar isIdentifierChar "identifier" .>> spaces
+    many1Satisfy2L isIdentifierFirstChar isIdentifierChar "identifier" .>> spacesOrComment
     >>= fun identifier ->
     if List.contains (identifier.ToUpper()) reserved
     then fail (sprintf "Identifier %s is a reserved keyword" identifier)
     else preturn identifier
 
 // Can be a reserved keyword.
 let quotedIdentifier : Parser<string, unit> =
-    (skipChar '\"' |> anyStringBetween <| skipChar '\"') .>> spaces
+    (skipChar '\"' |> anyStringBetween <| skipChar '\"') .>> spacesOrComment
 
 let stringIdentifier =
     quotedIdentifier
@@ -129,7 +131,7 @@ let parameter : Parser<Expr, unit> =
     |>> Expr.Parameter
 
 let text value : Parser<string, unit> =
-    (optional spaces) >>. pstringCI value .>> (optional spaces)
+    spaces >>. pstringCI value .>> spacesOrComment
 
 let star : Parser<Expr, unit> =
     text "*" |>> fun _ -> Expr.Star
@@ -143,11 +145,11 @@ let parens parser = between (text "(") (text ")") parser
 let comma = text ","
 
 let integer : Parser<Expr, unit> =
-    (optional spaces) >>. pint32 .>> (optional spaces)
+    spaces >>. pint32 .>> spacesOrComment
     |>> Expr.Integer
 
 let number : Parser<Expr, unit> =
-    (optional spaces) >>. pfloat .>> (optional spaces)
+    spaces >>. pfloat .>> spacesOrComment
     |>> Expr.Float
 
 let boolean : Parser<Expr, unit> =
@@ -365,11 +367,20 @@ let updateQuery =
 
         preturn (Expr.UpdateQuery query)
 
-opp.AddOperator(InfixOperator("AND", spaces, 7, Associativity.Left, fun left right -> Expr.And(left, right)))
-opp.AddOperator(InfixOperator("AS", spaces, 6, Associativity.Left, fun left right -> Expr.As(left, right)))
-opp.AddOperator(InfixOperator("as", spaces, 6, Associativity.Left, fun left right -> Expr.As(left, right)))
+let spacesOrComment =
+    let comment = skipString "/*" >>. (charsTillString "*/" true 8096)
+    let commentEol = skipString "--" >>. skipRestOfLine true
+
+    spaces .>>
+    optional comment .>>
+    optional commentEol .>>
+    spaces
+
+opp.AddOperator(InfixOperator("AND", spacesOrComment, 7, Associativity.Left, fun left right -> Expr.And(left, right)))
+opp.AddOperator(InfixOperator("AS", spacesOrComment, 6, Associativity.Left, fun left right -> Expr.As(left, right)))
+opp.AddOperator(InfixOperator("as", spacesOrComment, 6, Associativity.Left, fun left right -> Expr.As(left, right)))
 opp.AddOperator(InfixOperator("OR", notFollowedBy (text "DER BY"), 6, Associativity.Left, fun left right -> Expr.Or(left, right)))
-opp.AddOperator(InfixOperator("IN", spaces, 8, Associativity.Left, fun left right -> Expr.In(left, right)))
+opp.AddOperator(InfixOperator("IN", spacesOrComment, 8, Associativity.Left, fun left right -> Expr.In(left, right)))
 opp.AddOperator(InfixOperator(">", spaces, 9, Associativity.Left, fun left right -> Expr.GreaterThan(left, right)))
 opp.AddOperator(InfixOperator("<", spaces, 9, Associativity.Left, fun left right -> Expr.LessThan(left, right)))
 opp.AddOperator(InfixOperator("<=", spaces, 9, Associativity.Left, fun left right -> Expr.LessThanOrEqual(left, right)))
@@ -380,8 +391,8 @@ opp.AddOperator(InfixOperator("||", spaces, 9, Associativity.Left, fun left righ
 opp.AddOperator(InfixOperator("::", spaces, 9, Associativity.Left, fun left right -> Expr.TypeCast(left, right)))
 opp.AddOperator(InfixOperator("->>", spaces, 9, Associativity.Left, fun left right -> Expr.JsonIndex(left, right)))
 
-opp.AddOperator(PostfixOperator("IS NULL", spaces, 8, false, fun value -> Expr.Equals(Expr.Null, value)))
-opp.AddOperator(PostfixOperator("IS NOT NULL", spaces, 8, false, fun value -> Expr.Not(Expr.Equals(Expr.Null, value))))
+opp.AddOperator(PostfixOperator("IS NULL", spacesOrComment, 8, false, fun value -> Expr.Equals(Expr.Null, value)))
+opp.AddOperator(PostfixOperator("IS NOT NULL", spacesOrComment, 8, false, fun value -> Expr.Not(Expr.Equals(Expr.Null, value))))
 
 opp.TermParser <- choice [
     (attempt updateQuery)
@@ -399,7 +410,7 @@ opp.TermParser <- choice [
     parameter
 ]
 
-let fullParser = (optional spaces) >>. expr .>> (optional spaces <|> (text ";" |>> fun _ -> ()))
+let fullParser = spacesOrComment >>. expr .>> (spacesOrComment <|> (text ";" |>> ignore))
 
 let parse (input: string) : Result<Expr, string> =
     match run fullParser input with

tests/NpgsqlFSharpAnalyzer.Tests/ParseSelectTests.fs

@@ -513,4 +513,48 @@ let selectQueryTests = testList "Parse SELECT tests" [
             From = Expr.As(Expr.Ident "$Table", Expr.Ident "tbl") |> Some
             Limit = Some (Expr.Integer 100)
         }
-]
+
+    testSelect "SELECT 1 -- This is a comment" {
+        SelectExpr.Default with Columns = [Expr.Integer 1]
+    }
+
+    testSelect """
+        -- This is a comment
+        SELECT 1""" {
+        SelectExpr.Default with Columns = [Expr.Integer 1]
+    }
+
+    testSelect """
+        /* Comment inserted first */
+        SELECT 1""" {
+        SelectExpr.Default with Columns = [Expr.Integer 1]
+    }
+
+    testSelect """
+        SELECT 1
+        /* Comment inserted last */
+        """ {
+        SelectExpr.Default with Columns = [Expr.Integer 1]
+    }
+
+    testSelect """
+        SELECT 1;
+        /* Comment inserted after semicolon */
+        """ {
+        SelectExpr.Default with Columns = [Expr.Integer 1]
+    }
+
+    testSelect """
+        SELECT * /* Comment inserted here */
+        FROM -- Ignore
+        (SELECT NOW()) time /* Comment inserted here */
+        LIMIT 1 -- Ignore
+    """ {
+        SelectExpr.Default with
+            Columns = [Expr.Star]
+            From = Some (Expr.As (Expr.SelectQuery {
+                SelectExpr.Default with
+                    Columns = [Expr.Function ("NOW", [])]
+            }, Expr.Ident "time"))
+            Limit = Some (Expr.Integer 1)
+    }]