Handling large integers (#202)

* Handling large integers

Signed-off-by: Prafulla Mahindrakar <[email protected]>

clients/go/coreutils/literals.go

@@ -4,6 +4,7 @@ package coreutils
 import (
 	"encoding/json"
 	"fmt"
+	"math"
 	"reflect"
 	"strconv"
 	"strings"
@@ -492,7 +493,13 @@ func MakeLiteralForType(t *core.LiteralType, v interface{}) (*core.Literal, erro
 		if v == nil {
 			strValue = ""
 		}
-
+		// Note this is to support large integers which by default when passed from an unmarshalled json will be
+		// converted to float64 and printed as exponential format by Sprintf.
+		// eg : 8888888 get converted to 8.888888e+06 and which causes strconv.ParseInt to fail
+		// Inorder to avoid this we explicitly add this check.
+		if f, ok := v.(float64); ok && math.Trunc(f) == f {
+			strValue = fmt.Sprintf("%.0f", math.Trunc(f))
+		}
 		if newT.Simple == core.SimpleType_STRUCT {
 			if _, isValueStringType := v.(string); !isValueStringType {
 				byteValue, err := json.Marshal(v)

clients/go/coreutils/literals_test.go

@@ -6,6 +6,7 @@ package coreutils
 import (
 	"fmt"
 	"reflect"
+	"strconv"
 	"testing"
 	"time"
 
@@ -16,6 +17,7 @@ import (
 
 	"github.com/golang/protobuf/ptypes"
 	structpb "github.com/golang/protobuf/ptypes/struct"
+	"github.com/pkg/errors"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -391,6 +393,30 @@ func TestMakeLiteralForType(t *testing.T) {
 		assert.Equal(t, expectedVal, actualVal)
 	})
 
+	t.Run("IntegerComingInAsFloatOverFlow", func(t *testing.T) {
+		var literalType = &core.LiteralType{Type: &core.LiteralType_Simple{Simple: core.SimpleType_INTEGER}}
+		_, err := MakeLiteralForType(literalType, 8.888888e+19)
+		assert.NotNil(t, err)
+		numError := &strconv.NumError{
+			Func: "ParseInt",
+			Num:  "88888880000000000000",
+			Err:  fmt.Errorf("value out of range"),
+		}
+		parseIntError := errors.WithMessage(numError, "failed to parse integer value")
+		assert.Equal(t, errors.WithStack(parseIntError).Error(), err.Error())
+	})
+
+	t.Run("IntegerComingInAsFloat", func(t *testing.T) {
+		var literalType = &core.LiteralType{Type: &core.LiteralType_Simple{Simple: core.SimpleType_INTEGER}}
+		val, err := MakeLiteralForType(literalType, 8.888888e+18)
+		assert.NoError(t, err)
+		literalVal := &core.Literal{Value: &core.Literal_Scalar{Scalar: &core.Scalar{
+			Value: &core.Scalar_Primitive{Primitive: &core.Primitive{Value: &core.Primitive_Integer{Integer: 8.888888e+18}}}}}}
+		expectedVal, _ := ExtractFromLiteral(literalVal)
+		actualVal, _ := ExtractFromLiteral(val)
+		assert.Equal(t, expectedVal, actualVal)
+	})
+
 	t.Run("SimpleFloat", func(t *testing.T) {
 		var literalType = &core.LiteralType{Type: &core.LiteralType_Simple{Simple: core.SimpleType_FLOAT}}
 		val, err := MakeLiteralForType(literalType, 1)