Include stack trace in errors

Author: Gael du Plessix

executor.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"reflect"
+	"runtime/debug"
 	"strings"
 
 	"github.com/graphql-go/graphql/gqlerrors"
@@ -61,7 +62,9 @@ func Execute(p ExecuteParams) (result *Result) {
 				if r, ok := r.(error); ok {
 					err = gqlerrors.FormatError(r)
 				}
-				exeContext.Errors = append(exeContext.Errors, gqlerrors.FormatError(err))
+				formattedErr := gqlerrors.FormatError(err)
+				formattedErr.StackTrace = string(debug.Stack())
+				exeContext.Errors = append(exeContext.Errors, formattedErr)
 				result.Errors = exeContext.Errors
 				select {
 				case out <- result:

gqlerrors/formatted.go

@@ -7,8 +7,9 @@ import (
 )
 
 type FormattedError struct {
-	Message   string                    `json:"message"`
-	Locations []location.SourceLocation `json:"locations"`
+	Message    string                    `json:"message"`
+	Locations  []location.SourceLocation `json:"locations"`
+	StackTrace string                    `json:"-"`
 }
 
 func (g FormattedError) Error() string {

nonnull_test.go

@@ -1032,10 +1032,19 @@ func TestNonNull_NullsTheTopLevelIfSyncNonNullableFieldThrows(t *testing.T) {
 	if len(result.Errors) != len(expected.Errors) {
 		t.Fatalf("Unexpected errors, Diff: %v", testutil.Diff(expected.Errors, result.Errors))
 	}
+	ignoreStackTraces(result)
 	if !reflect.DeepEqual(expected, result) {
+		t.Logf("=> err: %v", result.Errors[0].StackTrace)
 		t.Fatalf("Unexpected result, Diff: %v", testutil.Diff(expected, result))
 	}
 }
+
+func ignoreStackTraces(res *graphql.Result) {
+	for i, _ := range res.Errors {
+		res.Errors[i].StackTrace = ""
+	}
+}
+
 func TestNonNull_NullsTheTopLevelIfSyncNonNullableFieldErrors(t *testing.T) {
 	doc := `
       query Q { nonNullPromise }
@@ -1064,6 +1073,7 @@ func TestNonNull_NullsTheTopLevelIfSyncNonNullableFieldErrors(t *testing.T) {
 	if len(result.Errors) != len(expected.Errors) {
 		t.Fatalf("Unexpected errors, Diff: %v", testutil.Diff(expected.Errors, result.Errors))
 	}
+	ignoreStackTraces(result)
 	if !reflect.DeepEqual(expected, result) {
 		t.Fatalf("Unexpected result, Diff: %v", testutil.Diff(expected, result))
 	}
@@ -1096,6 +1106,7 @@ func TestNonNull_NullsTheTopLevelIfSyncNonNullableFieldReturnsNull(t *testing.T)
 	if len(result.Errors) != len(expected.Errors) {
 		t.Fatalf("Unexpected errors, Diff: %v", testutil.Diff(expected.Errors, result.Errors))
 	}
+	ignoreStackTraces(result)
 	if !reflect.DeepEqual(expected, result) {
 		t.Fatalf("Unexpected result, Diff: %v", testutil.Diff(expected, result))
 	}
@@ -1128,6 +1139,7 @@ func TestNonNull_NullsTheTopLevelIfSyncNonNullableFieldResolvesNull(t *testing.T
 	if len(result.Errors) != len(expected.Errors) {
 		t.Fatalf("Unexpected errors, Diff: %v", testutil.Diff(expected.Errors, result.Errors))
 	}
+	ignoreStackTraces(result)
 	if !reflect.DeepEqual(expected, result) {
 		t.Fatalf("Unexpected result, Diff: %v", testutil.Diff(expected, result))
 	}