Fix ranges with text format where end is unbounded

fixes #342

int4range_test.go

@@ -12,6 +12,8 @@ func TestInt4rangeTranscode(t *testing.T) {
 		&pgtype.Int4range{LowerType: pgtype.Empty, UpperType: pgtype.Empty, Status: pgtype.Present},
 		&pgtype.Int4range{Lower: pgtype.Int4{Int: 1, Status: pgtype.Present}, Upper: pgtype.Int4{Int: 10, Status: pgtype.Present}, LowerType: pgtype.Inclusive, UpperType: pgtype.Exclusive, Status: pgtype.Present},
 		&pgtype.Int4range{Lower: pgtype.Int4{Int: -42, Status: pgtype.Present}, Upper: pgtype.Int4{Int: -5, Status: pgtype.Present}, LowerType: pgtype.Inclusive, UpperType: pgtype.Exclusive, Status: pgtype.Present},
+		&pgtype.Int4range{Lower: pgtype.Int4{Int: 1, Status: pgtype.Present}, LowerType: pgtype.Inclusive, UpperType: pgtype.Unbounded, Status: pgtype.Present},
+		&pgtype.Int4range{Upper: pgtype.Int4{Int: 1, Status: pgtype.Present}, LowerType: pgtype.Unbounded, UpperType: pgtype.Exclusive, Status: pgtype.Present},
 		&pgtype.Int4range{Status: pgtype.Null},
 	})
 }

int8range_test.go

@@ -12,6 +12,8 @@ func TestInt8rangeTranscode(t *testing.T) {
 		&pgtype.Int8range{LowerType: pgtype.Empty, UpperType: pgtype.Empty, Status: pgtype.Present},
 		&pgtype.Int8range{Lower: pgtype.Int8{Int: 1, Status: pgtype.Present}, Upper: pgtype.Int8{Int: 10, Status: pgtype.Present}, LowerType: pgtype.Inclusive, UpperType: pgtype.Exclusive, Status: pgtype.Present},
 		&pgtype.Int8range{Lower: pgtype.Int8{Int: -42, Status: pgtype.Present}, Upper: pgtype.Int8{Int: -5, Status: pgtype.Present}, LowerType: pgtype.Inclusive, UpperType: pgtype.Exclusive, Status: pgtype.Present},
+		&pgtype.Int8range{Lower: pgtype.Int8{Int: 1, Status: pgtype.Present}, LowerType: pgtype.Inclusive, UpperType: pgtype.Unbounded, Status: pgtype.Present},
+		&pgtype.Int8range{Upper: pgtype.Int8{Int: 1, Status: pgtype.Present}, LowerType: pgtype.Unbounded, UpperType: pgtype.Exclusive, Status: pgtype.Present},
 		&pgtype.Int8range{Status: pgtype.Null},
 	})
 }

numrange_test.go

@@ -29,6 +29,18 @@ func TestNumrangeTranscode(t *testing.T) {
 			UpperType: pgtype.Exclusive,
 			Status:    pgtype.Present,
 		},
+		&pgtype.Numrange{
+			Lower:     pgtype.Numeric{Int: big.NewInt(-42), Exp: 1, Status: pgtype.Present},
+			LowerType: pgtype.Inclusive,
+			UpperType: pgtype.Unbounded,
+			Status:    pgtype.Present,
+		},
+		&pgtype.Numrange{
+			Upper:     pgtype.Numeric{Int: big.NewInt(-42), Exp: 1, Status: pgtype.Present},
+			LowerType: pgtype.Unbounded,
+			UpperType: pgtype.Exclusive,
+			Status:    pgtype.Present,
+		},
 		&pgtype.Numrange{Status: pgtype.Null},
 	})
 }

range.go

@@ -79,28 +79,28 @@ func ParseUntypedTextRange(src string) (*UntypedTextRange, error) {
 	if err != nil {
 		return nil, errors.Errorf("invalid upper value: %v", err)
 	}
-	buf.UnreadRune()
 
 	if r == ')' || r == ']' {
 		utr.UpperType = Unbounded
 	} else {
+		buf.UnreadRune()
 		utr.Upper, err = rangeParseValue(buf)
 		if err != nil {
 			return nil, errors.Errorf("invalid upper value: %v", err)
 		}
-	}
 
-	r, _, err = buf.ReadRune()
+		r, _, err = buf.ReadRune()
-	if err != nil {
+		if err != nil {
-		return nil, errors.Errorf("missing upper bound: %v", err)
+			return nil, errors.Errorf("missing upper bound: %v", err)
-	}
+		}
-	switch r {
+		switch r {
-	case ')':
+		case ')':
-		utr.UpperType = Exclusive
+			utr.UpperType = Exclusive
-	case ']':
+		case ']':
-		utr.UpperType = Inclusive
+			utr.UpperType = Inclusive
-	default:
+		default:
-		return nil, errors.Errorf("missing upper bound, instead got: %v", string(r))
+			return nil, errors.Errorf("missing upper bound, instead got: %v", string(r))
+		}
 	}
 
 	skipWhitespace(buf)