add property-based tests

package.json

@@ -35,6 +35,7 @@
         "@typescript-eslint/parser": "^5.2.0",
         "builtin-modules": "^3.2.0",
         "esbuild": "0.13.12",
+        "fast-check": "^3.8.0",
         "husky": "^7.0.4",
         "jest": "^29.3.1",
         "obsidian": "^0.16.3",
@@ -66,6 +67,7 @@
         "react": "^17.0.2",
         "react-dom": "^17.0.2",
         "rrule": "^2.7.2",
-        "zod": "^3.21.4"
+        "zod": "^3.21.4",
+        "zod-fast-check": "^0.9.0"
     }
 }

src/types/schema.test.ts

@@ -1,4 +1,13 @@
-import { parseEvent } from "./schema";
+import {
+    CommonSchema,
+    EventSchema,
+    OFCEvent,
+    TimeSchema,
+    parseEvent,
+    serializeEvent,
+} from "./schema";
+import fc from "fast-check";
+import { ZodFastCheck } from "zod-fast-check";
 
 describe("schema parsing tests", () => {
     describe("single events", () => {
@@ -331,4 +340,44 @@ describe("schema parsing tests", () => {
             `);
         });
     });
+
+    it("parses", () => {
+        const CommonArb = ZodFastCheck().inputOf(CommonSchema);
+        const TimeArb = ZodFastCheck().inputOf(TimeSchema);
+        const EventArb = ZodFastCheck().inputOf(EventSchema);
+        const EventInputArbitrary = fc
+            .tuple(CommonArb, TimeArb, EventArb)
+            .map(([common, time, event]) => ({
+                ...common,
+                ...time,
+                ...event,
+            }));
+
+        fc.assert(
+            fc.property(EventInputArbitrary, (obj) => {
+                expect(() => parseEvent(obj)).not.toThrow();
+            })
+        );
+    });
+
+    it("roundtrips", () => {
+        const CommonArb = ZodFastCheck().outputOf(CommonSchema);
+        const TimeArb = ZodFastCheck().outputOf(TimeSchema);
+        const EventArb = ZodFastCheck().outputOf(EventSchema);
+        const OFCEventArbitrary: fc.Arbitrary<OFCEvent> = fc
+            .tuple(CommonArb, TimeArb, EventArb)
+            .map(([common, time, event]) => ({
+                ...common,
+                ...time,
+                ...event,
+            }));
+
+        fc.assert(
+            fc.property(OFCEventArbitrary, (event) => {
+                const obj = serializeEvent(event);
+                const newParsedEvent = parseEvent(obj);
+                expect(newParsedEvent).toEqual(event);
+            })
+        );
+    });
 });

src/types/schema.ts

@@ -55,7 +55,7 @@ const parsedTime = () => z.string();
 //     );
 // });
 
-const TimeSchema = z.union([
+export const TimeSchema = z.union([
     z.object({ allDay: z.literal(true) }),
     z.object({
         allDay: z.literal(false).default(false),
@@ -64,9 +64,12 @@ const TimeSchema = z.union([
     }),
 ]);
 
-const CommonSchema = z.object({ title: z.string(), id: z.string().optional() });
+export const CommonSchema = z.object({
+    title: z.string(),
+    id: z.string().optional(),
+});
 
-const EventSchema = z.union([
+export const EventSchema = z.union([
     z.object({
         type: z.literal("single").optional(),
         date: z.string(),
@@ -118,3 +121,15 @@ export function validateEvent(obj: unknown): OFCEvent | null {
         return null;
     }
 }
+type Json =
+    | { [key: string]: Json }
+    | Json[]
+    | string
+    | number
+    | true
+    | false
+    | null;
+
+export function serializeEvent(obj: OFCEvent): Json {
+    return { ...obj };
+}