split isIntegralNumber func

cloudflare/d1/rows.go

@@ -51,6 +51,15 @@ func (r *rows) Close() error {
 	return nil
 }
 
+// isIntegralNumber returns if given float64 value is integral value or not.
+func isIntegralNumber(f float64) bool {
+	// If the value is NaN or Inf, returns the value to avoid being mistakenly treated as an integral value.
+	if math.IsNaN(f) || math.IsInf(f, 0) {
+		return false
+	}
+	return f == math.Trunc(f)
+}
+
 // convertRowColumnValueToDriverValue converts row column's value in JS to Go's driver.Value.
 // row column value is `null | Number | String | ArrayBuffer`.
 // see: https://developers.cloudflare.com/d1/platform/client-api/#type-conversion
@@ -60,8 +69,8 @@ func convertRowColumnValueToAny(v js.Value) (driver.Value, error) {
 		return nil, nil
 	case js.TypeNumber:
 		fv := v.Float()
-		// if the value can be treated as integer, return as int64.
-		if fv == math.Trunc(fv) {
+		// if the value can be treated as integral value, return as int64.
+		if isIntegralNumber(fv) {
 			return int64(fv), nil
 		}
 		return fv, nil

cloudflare/d1/rows_test.go

@@ -0,0 +1,44 @@
+package d1
+
+import (
+	"math"
+	"testing"
+)
+
+func Test_isIntegralNumber(t *testing.T) {
+	tests := map[string]struct {
+		f    float64
+		want bool
+	}{
+		"valid integral value": {
+			f:    1,
+			want: true,
+		},
+		"invalid float value": {
+			f:    1.1,
+			want: false,
+		},
+		"invalid NaN": {
+			f:    math.NaN(),
+			want: false,
+		},
+		"invalid +Inf": {
+			f:    math.Inf(+1),
+			want: false,
+		},
+		"invalid -Inf": {
+			f:    math.Inf(-1),
+			want: false,
+		},
+	}
+	for name, tc := range tests {
+		name := name
+		tc := tc
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+			if got := isIntegralNumber(tc.f); got != tc.want {
+				t.Errorf("isIntegralNumber() = %v, want %v", got, tc.want)
+			}
+		})
+	}
+}