Fixing error thrown when field is of type "Function"

Author: jfurler

.gitignore

@@ -3,4 +3,5 @@ test/*.js
 test/*.d.ts
 test/*.map
 .vscode/*.*
-npm-debug.log
+npm-debug.log
+.idea

test/programs/type-function/main.ts

@@ -0,0 +1,3 @@
+interface MyObject {
+    myFunction: Function;
+}

test/programs/type-function/schema.json

@@ -0,0 +1,54 @@
+{
+  "$schema": "http://json-schema.org/draft-04/schema#",
+  "definitions": {
+    "Function": {
+      "description": "Creates a new function.",
+      "properties": {
+        "apply": {
+          "description": "Calls the function, substituting the specified object for the this value of the function, and the specified array for the arguments of the function.",
+          "type": "object"
+        },
+        "arguments": {},
+        "bind": {
+          "description": "For a given function, creates a bound function that has the same body as the original function.\nThe this object of the bound function is associated with the specified object, and has the specified initial parameters.",
+          "type": "object"
+        },
+        "call": {
+          "description": "Calls a method of an object, substituting another object for the current object.",
+          "type": "object"
+        },
+        "caller": {
+          "$ref": "#/definitions/Function"
+        },
+        "length": {
+          "type": "number"
+        },
+        "prototype": {},
+        "toString": {
+          "description": "Returns a string representation of a function.",
+          "type": "object"
+        }
+      },
+      "required": [
+        "apply",
+        "arguments",
+        "bind",
+        "call",
+        "caller",
+        "length",
+        "prototype",
+        "toString"
+      ],
+      "type": "object"
+    }
+  },
+  "properties": {
+    "myFunction": {
+      "$ref": "#/definitions/Function"
+    }
+  },
+  "required": [
+    "myFunction"
+  ],
+  "type": "object"
+}

test/schema.test.ts

@@ -170,6 +170,7 @@ describe("schema", () => {
         assertSchema("type-anonymous", "MyObject");
         assertSchema("type-primitives", "MyObject");
         assertSchema("type-nullable", "MyObject");
+        assertSchema("type-function", "MyObject");
     });
 
     describe("class and interface", () => {
@@ -207,7 +208,7 @@ describe("schema", () => {
         assertSchema("string-literals-inline", "MyObject");
     });
 
-    describe("namspeaces", () => {
+    describe("namespaces", () => {
         assertSchema("namespace", "Type");
         assertSchema("namespace-deep-1", "RootNamespace.Def");
         assertSchema("namespace-deep-2", "RootNamespace.SubNamespace.HelperA");

typescript-json-schema.ts

@@ -543,29 +543,31 @@ export class JsonSchemaGenerator {
 
             definition.oneOf = oneOf;
         } else {
-            const indexSignatures = clazz.members.filter(x => x.kind === ts.SyntaxKind.IndexSignature);
-            if (indexSignatures.length === 1) {
-                // for case "array-types"
-                const indexSignature = indexSignatures[0] as ts.IndexSignatureDeclaration;
-                if (indexSignature.parameters.length !== 1) {
-                    throw "Not supported: IndexSignatureDeclaration parameters.length != 1";
-                }
-                const indexSymbol: ts.Symbol = (<any>indexSignature.parameters[0]).symbol;
-                const indexType = tc.getTypeOfSymbolAtLocation(indexSymbol, node);
-                const isStringIndexed = (indexType.flags === ts.TypeFlags.String);
-                if (indexType.flags !== ts.TypeFlags.Number && !isStringIndexed) {
-                    throw "Not supported: IndexSignatureDeclaration with index symbol other than a number or a string";
-                }
+            if (clazz.members) {
+                const indexSignatures = clazz.members.filter(x => x.kind === ts.SyntaxKind.IndexSignature);
+                if (indexSignatures.length === 1) {
+                    // for case "array-types"
+                    const indexSignature = indexSignatures[0] as ts.IndexSignatureDeclaration;
+                    if (indexSignature.parameters.length !== 1) {
+                        throw "Not supported: IndexSignatureDeclaration parameters.length != 1";
+                    }
+                    const indexSymbol: ts.Symbol = (<any>indexSignature.parameters[0]).symbol;
+                    const indexType = tc.getTypeOfSymbolAtLocation(indexSymbol, node);
+                    const isStringIndexed = (indexType.flags === ts.TypeFlags.String);
+                    if (indexType.flags !== ts.TypeFlags.Number && !isStringIndexed) {
+                        throw "Not supported: IndexSignatureDeclaration with index symbol other than a number or a string";
+                    }
 
-                const typ = tc.getTypeAtLocation(indexSignature.type!);
-                const def = this.getTypeDefinition(typ, tc, undefined, "anyOf");
+                    const typ = tc.getTypeAtLocation(indexSignature.type!);
+                    const def = this.getTypeDefinition(typ, tc, undefined, "anyOf");
 
-                if (isStringIndexed) {
-                    definition.type = "object";
-                    definition.additionalProperties = def;
-                } else {
-                    definition.type = "array";
-                    definition.items = def;
+                    if (isStringIndexed) {
+                        definition.type = "object";
+                        definition.additionalProperties = def;
+                    } else {
+                        definition.type = "array";
+                        definition.items = def;
+                    }
                 }
             }