fix lexing of whitespace in number literals

In places where an optional space was previously allowed, allow any
number of arbitrary whitespace characters, in line with the spec and
other tools.

src/Language/SystemVerilog/AST/Number.hs

@@ -23,7 +23,7 @@ import Text.Read (readMaybe)
 -- visual niceties like spaces and underscores
 parseNumber :: String -> Number
 parseNumber = parseNumber' . map toLower . filter (not . isPad)
-    where isPad ch = ch == '_' || ch == ' '
+    where isPad = flip elem "_ \n\t"
 
 parseNumber' :: String -> Number
 parseNumber' ['\'', ch] = UnbasedUnsized ch

src/Language/SystemVerilog/Parser/Lex.x

@@ -53,19 +53,19 @@ import Language.SystemVerilog.Parser.Tokens
     = @fixedPointNumber
     | @unsignedNumber ("." @unsignedNumber)? @exp @sign? @unsignedNumber
 
-@size = @nonZeroUnsignedNumber " "?
+@size = @nonZeroUnsignedNumber $white*
 
-@binaryNumber = @size? @binaryBase " "? @binaryValue
-@octalNumber  = @size? @octalBase  " "? @octalValue
-@hexNumber    = @size? @hexBase    " "? @hexValue
+@binaryNumber = @size? @binaryBase $white* @binaryValue
+@octalNumber  = @size? @octalBase  $white* @octalValue
+@hexNumber    = @size? @hexBase    $white* @hexValue
 
 @unbasedUnsizedLiteral = "'" ( 0 | 1 | x | X | z | Z )
 
 @decimalNumber
     = @unsignedNumber
-    | @size? @decimalBase " "? @unsignedNumber
-    | @size? @decimalBase " "? @xDigit "_"*
-    | @size? @decimalBase " "? @zDigit "_"*
+    | @size? @decimalBase $white* @unsignedNumber
+    | @size? @decimalBase $white* @xDigit "_"*
+    | @size? @decimalBase $white* @zDigit "_"*
 @integralNumber
     = @decimalNumber
     | @octalNumber

test/lex/number_literal_whitespace.sv

+module top;
+    initial begin
+        $display("%b",
+            5
+            	/* intentional tab */
+            'b
+            	/* intentional tab */
+            01010
+        );
+        $display("%b",
+            3
+            	/* intentional tab */
+            'o
+            	/* intentional tab */
+            7
+        );
+        $display("%b",
+            8
+            	/* intentional tab */
+            'h
+            	/* intentional tab */
+            ab
+        );
+        $display("%b",
+            8
+            	/* intentional tab */
+            'd
+            	/* intentional tab */
+            11
+        );
+        $display("%b",
+            8
+            	/* intentional tab */
+            'd
+            	/* intentional tab */
+            x___
+        );
+        $display("%b",
+            8
+            	/* intentional tab */
+            'd
+            	/* intentional tab */
+            z___
+        );
+    end
+endmodule

test/lex/number_literal_whitespace.v

+module top;
+    initial begin
+        $display("%b", 5'b01010);
+        $display("%b", 3'o7);
+        $display("%b", 8'hab);
+        $display("%b", 8'd11);
+        $display("%b", 8'dx___);
+        $display("%b", 8'dz___);
+    end
+endmodule