Fix using enum values in interfaces (YousefED#123)

* Fix using enum values in interfaces

* Compact the enum members assignment

Author: marcindobry

test/programs/enums-value-in-interface/main.ts

@@ -0,0 +1,9 @@
+export enum A {
+  B,
+  C,
+  D,
+};
+
+export interface MyObject {
+  code: A.B;
+};

test/programs/enums-value-in-interface/schema.json

@@ -0,0 +1,20 @@
+{
+    "$schema": "http://json-schema.org/draft-04/schema#",
+    "definitions": {
+        "A.B": {
+            "enum": [
+                0
+            ],
+            "type": "number"
+        }
+    },
+    "properties": {
+        "code": {
+            "$ref": "#/definitions/A.B"
+        }
+    },
+    "required": [
+        "code"
+    ],
+    "type": "object"
+}

test/schema.test.ts

@@ -87,6 +87,7 @@ describe("schema", () => {
     assertSchema("enums-number-initialized", "main.ts", "Enum");
     assertSchema("enums-compiled-compute", "main.ts", "Enum");
     assertSchema("enums-mixed", "main.ts", "MyObject");
+    assertSchema("enums-value-in-interface", "main.ts", "MyObject");
     assertSchema("string-literals", "main.ts", "MyObject");
     assertSchema("string-literals-inline", "main.ts", "MyObject");
 
@@ -111,7 +112,7 @@ describe("schema", () => {
     assertSchema("imports", "main.ts", "MyObject");
 
     assertSchema("extra-properties", "main.ts", "MyObject");
-  
+
     assertSchema("generate-all-types", "main.ts", "*");
 
     /**

typescript-json-schema.ts

@@ -361,8 +361,9 @@ export class JsonSchemaGenerator {
     private getEnumDefinition(clazzType: ts.Type, tc: ts.TypeChecker, definition: Definition): Definition {
         const node = clazzType.getSymbol().getDeclarations()[0];
         const fullName = tc.typeToString(clazzType, undefined, ts.TypeFormatFlags.UseFullyQualifiedType);
-        const enm = <ts.EnumDeclaration>node;
-
+        const members: ts.EnumMember[] = node.kind === ts.SyntaxKind.EnumDeclaration ?
+            (node as ts.EnumDeclaration).members :
+            [node as ts.EnumMember];
         var enumValues: (number|boolean|string|null)[] = [];
         let enumTypes: string[] = [];
 
@@ -372,7 +373,7 @@ export class JsonSchemaGenerator {
             }
         };
 
-        enm.members.forEach(member => {
+        members.forEach(member => {
             const caseLabel = (<ts.Identifier>member.name).text;
             const constantValue = tc.getConstantValue(member);
             if (constantValue !== undefined) {