1 files changed, 86 insertions, 0 deletions
diff --git a/vendor/github.com/vektah/gqlparser/validator/rules/fields_on_correct_type.go b/vendor/github.com/vektah/gqlparser/validator/rules/fields_on_correct_type.go
new file mode 100644
index 00000000..69148d52
--- /dev/null
+++ b/vendor/github.com/vektah/gqlparser/validator/rules/fields_on_correct_type.go
@@ -0,0 +1,86 @@
+package validator
+
+import (
+	"fmt"
+	"sort"
+
+	"github.com/vektah/gqlparser/ast"
+	. "github.com/vektah/gqlparser/validator"
+)
+
+func init() {
+	AddRule("FieldsOnCorrectType", func(observers *Events, addError AddErrFunc) {
+		observers.OnField(func(walker *Walker, field *ast.Field) {
+			if field.ObjectDefinition == nil || field.Definition != nil {
+				return
+			}
+
+			message := fmt.Sprintf(`Cannot query field "%s" on type "%s".`, field.Name, field.ObjectDefinition.Name)
+
+			if suggestedTypeNames := getSuggestedTypeNames(walker, field.ObjectDefinition, field.Name); suggestedTypeNames != nil {
+				message += " Did you mean to use an inline fragment on " + QuotedOrList(suggestedTypeNames...) + "?"
+			} else if suggestedFieldNames := getSuggestedFieldNames(field.ObjectDefinition, field.Name); suggestedFieldNames != nil {
+				message += " Did you mean " + QuotedOrList(suggestedFieldNames...) + "?"
+			}
+
+			addError(
+				Message(message),
+				At(field.Position),
+			)
+		})
+	})
+}
+
+// Go through all of the implementations of type, as well as the interfaces
+// that they implement. If any of those types include the provided field,
+// suggest them, sorted by how often the type is referenced,  starting
+// with Interfaces.
+func getSuggestedTypeNames(walker *Walker, parent *ast.Definition, name string) []string {
+	if !parent.IsAbstractType() {
+		return nil
+	}
+
+	var suggestedObjectTypes []string
+	var suggestedInterfaceTypes []string
+	interfaceUsageCount := map[string]int{}
+
+	for _, possibleType := range walker.Schema.GetPossibleTypes(parent) {
+		field := possibleType.Fields.ForName(name)
+		if field == nil {
+			continue
+		}
+
+		suggestedObjectTypes = append(suggestedObjectTypes, possibleType.Name)
+
+		for _, possibleInterface := range possibleType.Interfaces {
+			interfaceField := walker.Schema.Types[possibleInterface]
+			if interfaceField != nil && interfaceField.Fields.ForName(name) != nil {
+				if interfaceUsageCount[possibleInterface] == 0 {
+					suggestedInterfaceTypes = append(suggestedInterfaceTypes, possibleInterface)
+				}
+				interfaceUsageCount[possibleInterface]++
+			}
+		}
+	}
+
+	sort.SliceStable(suggestedInterfaceTypes, func(i, j int) bool {
+		return interfaceUsageCount[suggestedInterfaceTypes[i]] > interfaceUsageCount[suggestedInterfaceTypes[j]]
+	})
+
+	return append(suggestedInterfaceTypes, suggestedObjectTypes...)
+}
+
+// For the field name provided, determine if there are any similar field names
+// that may be the result of a typo.
+func getSuggestedFieldNames(parent *ast.Definition, name string) []string {
+	if parent.Kind != ast.Object && parent.Kind != ast.Interface {
+		return nil
+	}
+
+	var possibleFieldNames []string
+	for _, field := range parent.Fields {
+		possibleFieldNames = append(possibleFieldNames, field.Name)
+	}
+
+	return SuggestionList(name, possibleFieldNames)
+}