Improve generated types for unknown schema objects (#769)

Fixes #693, #554

Author: drwpow

examples/stripe-openapi2.ts

@@ -99,7 +99,7 @@ export function transformSchemaObj(node: any, options: TransformSchemaObjOptions
       case "number":
       case "boolean":
       case "unknown": {
-        output += nodeType(node) || "any";
+        output += nodeType(node);
         break;
       }
       case "enum": {
@@ -139,7 +139,7 @@ export function transformSchemaObj(node: any, options: TransformSchemaObjOptions
           (node.additionalProperties === undefined && options.additionalProperties && options.version === 3)
         ) {
           if ((node.additionalProperties ?? true) === true || Object.keys(node.additionalProperties).length === 0) {
-            additionalProperties = `{ ${readonly}[key: string]: any }`;
+            additionalProperties = `{ ${readonly}[key: string]: unknown }`;
           } else if (typeof node.additionalProperties === "object") {
             const oneOf: any[] | undefined = (node.additionalProperties as any).oneOf || undefined; // TypeScript does a really bad job at inference here, so we enforce a type
             const anyOf: any[] | undefined = (node.additionalProperties as any).anyOf || undefined; // "
@@ -149,7 +149,7 @@ export function transformSchemaObj(node: any, options: TransformSchemaObjOptions
               additionalProperties = `{ ${readonly}[key: string]: ${transformAnyOf(anyOf, options)}; }`;
             } else {
               additionalProperties = `{ ${readonly}[key: string]: ${
-                transformSchemaObj(node.additionalProperties, options) || "any"
+                transformSchemaObj(node.additionalProperties, options) || "unknown"
               }; }`;
             }
           }
@@ -172,7 +172,7 @@ export function transformSchemaObj(node: any, options: TransformSchemaObjOptions
         if (Array.isArray(node.items)) {
           output += `${readonly}${tsTupleOf(node.items.map((node: any) => transformSchemaObj(node, options)))}`;
         } else {
-          output += `${readonly}${tsArrayOf(node.items ? transformSchemaObj(node.items as any, options) : "any")}`;
+          output += `${readonly}${tsArrayOf(node.items ? transformSchemaObj(node.items as any, options) : "unknown")}`;
         }
         break;
       }

examples/stripe-openapi3.ts

@@ -43,9 +43,9 @@ type SchemaObjectType =
   | "ref"
   | "string"
   | "unknown";
-export function nodeType(obj: any): SchemaObjectType | undefined {
+export function nodeType(obj: any): SchemaObjectType {
   if (!obj || typeof obj !== "object") {
-    return undefined;
+    return "unknown";
   }
 
   if (obj.$ref) {
@@ -77,13 +77,20 @@ export function nodeType(obj: any): SchemaObjectType | undefined {
     return "array";
   }
 
-  // file
-  if (obj.type === "file") {
-    return "unknown";
+  // object
+  if (
+    obj.type === "object" ||
+    obj.hasOwnProperty("allOf") ||
+    obj.hasOwnProperty("anyOf") ||
+    obj.hasOwnProperty("oneOf") ||
+    obj.hasOwnProperty("properties") ||
+    obj.hasOwnProperty("additionalProperties")
+  ) {
+    return "object";
   }
 
-  // return object by default
-  return "object";
+  // return unknown by default
+  return "unknown";
 }
 
 /** Return OpenAPI version from definition */

src/transform/schema.ts

@@ -89,7 +89,7 @@ describe("requestBodies", () => {
             content: {
               "application/json": {
                 test?: string;
-              } & { [key: string]: any };
+              } & { [key: string]: unknown };
             };
           };`)
     );

src/utils.ts

@@ -58,7 +58,7 @@ describe("SchemaObject", () => {
       expect(transform(objUnknown, { ...defaults })).toBe(`{ [key: string]: unknown }`);
 
       // empty
-      expect(transform({}, { ...defaults })).toBe(`{ [key: string]: unknown }`);
+      expect(transform({}, { ...defaults })).toBe(`unknown`);
 
       // nullable
       expect(transform(objNullable, { ...defaults })).toBe(`({\n"string"?: string;\n\n}) | null`);
@@ -74,7 +74,7 @@ describe("SchemaObject", () => {
         `{\nreadonly "object"?: {\nreadonly "string"?: string;\nreadonly "number"?: components["schemas"]["object_ref"];\n\n};\n\n}`
       );
       expect(transform(objUnknown, opts)).toBe(`{ readonly [key: string]: unknown }`);
-      expect(transform({}, opts)).toBe(`{ readonly [key: string]: unknown }`);
+      expect(transform({}, opts)).toBe(`unknown`);
       expect(transform(objNullable, opts)).toBe(`({\nreadonly "string"?: string;\n\n}) | null`);
       expect(transform(objRequired, opts)).toBe(`{\nreadonly "required": string;\nreadonly "optional"?: boolean;\n\n}`);
     });
@@ -218,10 +218,10 @@ describe("SchemaObject", () => {
   describe("advanced", () => {
     it("additionalProperties", () => {
       // boolean
-      expect(transform({ additionalProperties: true }, { ...defaults })).toBe(`{ [key: string]: any }`);
+      expect(transform({ additionalProperties: true }, { ...defaults })).toBe(`{ [key: string]: unknown }`);
 
       // empty object
-      expect(transform({ additionalProperties: {} }, { ...defaults })).toBe(`{ [key: string]: any }`);
+      expect(transform({ additionalProperties: {} }, { ...defaults })).toBe(`{ [key: string]: unknown }`);
 
       // type
       expect(transform({ additionalProperties: { type: "string" } }, { ...defaults })).toBe(