add safe cast for uint

99designs · Jun 2, 2023 · 78f39d6 · 78f39d6
1 parent dbb6117
commit 78f39d6
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Showing 4 changed files with 54 additions and 6 deletions.
diff --git a/go.mod b/go.mod
@@ -27,6 +27,7 @@ require (
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect
+	golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1 // indirect
 	golang.org/x/mod v0.8.0 // indirect
 	golang.org/x/sys v0.5.0 // indirect
 )
diff --git a/go.sum b/go.sum
@@ -60,6 +60,8 @@ github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673/go.mod h1:N3UwUGtsr
 github.com/yuin/goldmark v1.4.1/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
+golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1 h1:k/i9J1pBpvlfR+9QsetwPyERsqu1GIbi967PQMq3Ivc=
+golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1/go.mod h1:V1LtkGg67GoY2N1AnLN78QLrzxkLyJw7RJb1gzOOz9w=
 golang.org/x/mod v0.6.0-dev.0.20220106191415-9b9b3d81d5e3/go.mod h1:3p9vT2HGsQu2K1YbXdKPJLVgG5VJdoTa1poYQBtP1AY=
 golang.org/x/mod v0.8.0 h1:LUYupSeNrTNCGzR/hVBk2NHZO4hXcVaW1k4Qx7rjPx8=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=

diff --git a/graphql/uint.go b/graphql/uint.go
@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"io"
 	"strconv"
+
+	"golang.org/x/exp/constraints"
 )
 
 func MarshalUint(i uint) Marshaler {
@@ -19,9 +21,9 @@ func UnmarshalUint(v interface{}) (uint, error) {
 		u64, err := strconv.ParseUint(v, 10, 64)
 		return uint(u64), err
 	case int:
-		return uint(v), nil
+		return safeUintCast[int, uint](v)
 	case int64:
-		return uint(v), nil
+		return safeUintCast[int64, uint](v)
 	case json.Number:
 		u64, err := strconv.ParseUint(string(v), 10, 64)
 		return uint(u64), err
@@ -41,9 +43,9 @@ func UnmarshalUint64(v interface{}) (uint64, error) {
 	case string:
 		return strconv.ParseUint(v, 10, 64)
 	case int:
-		return uint64(v), nil
+		return safeUintCast[int, uint64](v)
 	case int64:
-		return uint64(v), nil
+		return safeUintCast[int64, uint64](v)
 	case json.Number:
 		return strconv.ParseUint(string(v), 10, 64)
 	default:
@@ -66,9 +68,9 @@ func UnmarshalUint32(v interface{}) (uint32, error) {
 		}
 		return uint32(iv), nil
 	case int:
-		return uint32(v), nil
+		return safeUintCast[int, uint32](v)
 	case int64:
-		return uint32(v), nil
+		return safeUintCast[int64, uint32](v)
 	case json.Number:
 		iv, err := strconv.ParseUint(string(v), 10, 32)
 		if err != nil {
@@ -79,3 +81,10 @@ func UnmarshalUint32(v interface{}) (uint32, error) {
 		return 0, fmt.Errorf("%T is not an uint", v)
 	}
 }
+
+func safeUintCast[F constraints.Signed, T constraints.Unsigned](f F) (T, error) {
+	if f < 0 {
+		return 0, fmt.Errorf("cannot cast %d to uint", f)
+	}
+	return T(f), nil
+}
diff --git a/graphql/uint_test.go b/graphql/uint_test.go
@@ -18,6 +18,10 @@ func TestUint(t *testing.T) {
 		assert.Equal(t, uint(123), mustUnmarshalUint(int64(123)))
 		assert.Equal(t, uint(123), mustUnmarshalUint(json.Number("123")))
 		assert.Equal(t, uint(123), mustUnmarshalUint("123"))
+		assert.NotNil(t, mustFailUnmarshalUint(-2))
+		assert.NotNil(t, mustFailUnmarshalUint(int64(-123)))
+		assert.NotNil(t, mustFailUnmarshalUint("-4294967295"))
+		assert.NotNil(t, mustFailUnmarshalUint(json.Number("-123")))
 	})
 }
 
@@ -29,6 +33,14 @@ func mustUnmarshalUint(v interface{}) uint {
 	return res
 }
 
+func mustFailUnmarshalUint(v interface{}) error {
+	_, err := UnmarshalUint(v)
+	if err == nil {
+		panic(err)
+	}
+	return err
+}
+
 func TestUint32(t *testing.T) {
 	t.Run("marshal", func(t *testing.T) {
 		assert.Equal(t, "123", m2s(MarshalUint32(123)))
@@ -41,6 +53,10 @@ func TestUint32(t *testing.T) {
 		assert.Equal(t, uint32(123), mustUnmarshalUint32(json.Number("123")))
 		assert.Equal(t, uint32(123), mustUnmarshalUint32("123"))
 		assert.Equal(t, uint32(4294967295), mustUnmarshalUint32("4294967295"))
+		assert.NotNil(t, mustFailUnmarshalUint32(-2))
+		assert.NotNil(t, mustFailUnmarshalUint32(int64(-123)))
+		assert.NotNil(t, mustFailUnmarshalUint32("-4294967295"))
+		assert.NotNil(t, mustFailUnmarshalUint32(json.Number("-123")))
 	})
 }
 
@@ -52,6 +68,14 @@ func mustUnmarshalUint32(v interface{}) uint32 {
 	return res
 }
 
+func mustFailUnmarshalUint32(v interface{}) error {
+	_, err := UnmarshalUint32(v)
+	if err == nil {
+		panic(err)
+	}
+	return err
+}
+
 func TestUint64(t *testing.T) {
 	t.Run("marshal", func(t *testing.T) {
 		assert.Equal(t, "123", m2s(MarshalUint64(123)))
@@ -62,6 +86,10 @@ func TestUint64(t *testing.T) {
 		assert.Equal(t, uint64(123), mustUnmarshalUint64(int64(123)))
 		assert.Equal(t, uint64(123), mustUnmarshalUint64(json.Number("123")))
 		assert.Equal(t, uint64(123), mustUnmarshalUint64("123"))
+		assert.NotNil(t, mustFailUnmarshalUint64(-2))
+		assert.NotNil(t, mustFailUnmarshalUint64(int64(-123)))
+		assert.NotNil(t, mustFailUnmarshalUint64("-4294967295"))
+		assert.NotNil(t, mustFailUnmarshalUint64(json.Number("-123")))
 	})
 }
 
@@ -72,3 +100,11 @@ func mustUnmarshalUint64(v interface{}) uint64 {
 	}
 	return res
 }
+
+func mustFailUnmarshalUint64(v interface{}) error {
+	_, err := UnmarshalUint64(v)
+	if err == nil {
+		panic(err)
+	}
+	return err
+}