feat(IsObject): maxProperties option (#7)

glebbash · Feb 7, 2022 · c2ded78 · c2ded78
1 parent 30c0f94
commit c2ded78
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Showing 2 changed files with 122 additions and 2 deletions.
diff --git a/src/decorators/is-object.spec.ts b/src/decorators/is-object.spec.ts
@@ -59,6 +59,103 @@ describe('IsObject', () => {
       expect(await input(Test, { objectField: false })).toStrictEqual(
         Result.err('objectField must be an object')
       );
+      expect(await input(Test, { objectField: undefined })).toStrictEqual(
+        Result.err('objectField must be an object')
+      );
+      expect(await input(Test, { objectField: null })).toStrictEqual(
+        Result.err('objectField must be an object')
+      );
+    });
+
+    it('checks maxProperties', async () => {
+      class Test {
+        @IsObject({ maxProperties: 1 })
+        objectField!: Record<string, unknown>;
+      }
+
+      expect(await input(Test, { objectField: { a: 1 } })).toStrictEqual(
+        Result.ok(make(Test, { objectField: { a: 1 } }))
+      );
+      expect(await input(Test, { objectField: { a: 1, b: 2 } })).toStrictEqual(
+        Result.err('objectField must have at most 1 properties')
+      );
+      expect(await input(Test, { objectField: false })).toStrictEqual(
+        Result.err('objectField must be an object')
+      );
+      expect(await input(Test, { objectField: undefined })).toStrictEqual(
+        Result.err('objectField must be an object')
+      );
+      expect(await input(Test, { objectField: null })).toStrictEqual(
+        Result.err('objectField must be an object')
+      );
+    });
+
+    it('works with minProperties && nullable', async () => {
+      class Test {
+        @IsObject({ minProperties: 1, nullable: true })
+        objectField!: Record<string, unknown> | null;
+      }
+
+      expect(await input(Test, { objectField: { a: 1 } })).toStrictEqual(
+        Result.ok(make(Test, { objectField: { a: 1 } }))
+      );
+      expect(await input(Test, { objectField: undefined })).toStrictEqual(
+        Result.err('objectField must be an object')
+      );
+      expect(await input(Test, { objectField: null })).toStrictEqual(
+        Result.ok(make(Test, { objectField: null }))
+      );
+    });
+
+    it('works with minProperties && optional', async () => {
+      class Test {
+        @IsObject({ minProperties: 1, optional: true })
+        objectField?: Record<string, unknown>;
+      }
+
+      expect(await input(Test, { objectField: { a: 1 } })).toStrictEqual(
+        Result.ok(make(Test, { objectField: { a: 1 } }))
+      );
+      expect(await input(Test, { objectField: undefined })).toStrictEqual(
+        Result.ok(make(Test, {}))
+      );
+      expect(await input(Test, { objectField: null })).toStrictEqual(
+        Result.err('objectField must be an object')
+      );
+    });
+
+    it('works with maxProperties && nullable', async () => {
+      class Test {
+        @IsObject({ maxProperties: 1, nullable: true })
+        objectField!: Record<string, unknown> | null;
+      }
+
+      expect(await input(Test, { objectField: { a: 1 } })).toStrictEqual(
+        Result.ok(make(Test, { objectField: { a: 1 } }))
+      );
+      expect(await input(Test, { objectField: undefined })).toStrictEqual(
+        Result.err('objectField must be an object')
+      );
+      expect(await input(Test, { objectField: null })).toStrictEqual(
+        Result.ok(make(Test, { objectField: null }))
+      );
+    });
+
+    it('works with maxProperties && optional', async () => {
+      class Test {
+        @IsObject({ maxProperties: 1, optional: true })
+        objectField?: Record<string, unknown>;
+      }
+
+      expect(await input(Test, { objectField: { a: 1 } })).toStrictEqual(
+        Result.ok(make(Test, { objectField: { a: 1 } }))
+      );
+      expect(await input(Test, { objectField: undefined })).toStrictEqual(
+        Result.ok(make(Test, {}))
+      );
+      expect(await input(Test, { objectField: null })).toStrictEqual(
+        Result.err('objectField must be an object')
+      );
     });
   });
 

diff --git a/src/decorators/is-object.ts b/src/decorators/is-object.ts
@@ -2,29 +2,52 @@ import { IsObject as IsObjectCV, ValidateBy } from 'class-validator';
 
 import { compose, noop, PropertyOptions } from '../core';
 
+function validateObjectSize(
+  obj: Record<string, unknown> | undefined | null,
+  check: (len: number) => boolean
+): boolean {
+  if (!obj) {
+    return true;
+  }
+
+  return check(Object.keys(obj).length);
+}
+
 export const IsObject = <T extends Record<string, unknown>>({
   message,
   minProperties,
+  maxProperties,
   ...base
 }: PropertyOptions<
   T,
   {
     message?: string;
     minProperties?: number;
+    maxProperties?: number;
   }
 > = {}): PropertyDecorator =>
   compose(
-    { type: 'object', minProperties },
+    { type: 'object', minProperties, maxProperties },
     base,
     IsObjectCV({ each: !!base.isArray, message }),
     minProperties
       ? ValidateBy({
           name: 'minProperties',
           validator: {
-            validate: (v) => Object.keys(v).length >= minProperties,
+            validate: (v) => validateObjectSize(v, (length) => length >= minProperties),
             defaultMessage: (args) =>
               `${args?.property} must have at least ${minProperties} properties`,
           },
         })
+      : noop,
+    maxProperties
+      ? ValidateBy({
+          name: 'maxProperties',
+          validator: {
+            validate: (v) => validateObjectSize(v, (length) => length <= maxProperties),
+            defaultMessage: (args) =>
+              `${args?.property} must have at most ${maxProperties} properties`,
+          },
+        })
       : noop
   );