fix: check for function condition first, array later

src/query.ts

@@ -82,6 +82,14 @@ export class Query<T> {
               return false
             }
 
+            /**
+             * @note Predicate functions receive the actual value as-is,
+             * including arrays and objects, so check for them first.
+             */
+            if (typeof selector === 'function') {
+              return selector(actualValue)
+            }
+
             if (Array.isArray(actualValue)) {
               return actualValue.every((value) => {
                 return compileCondition(selector)(value)
@@ -92,10 +100,6 @@ export class Query<T> {
               return compileCondition(selector)(actualValue)
             }
 
-            if (typeof selector === 'function') {
-              return selector(actualValue)
-            }
-
             return actualValue === selector
           })
         }

tests/query.test.ts

@@ -60,3 +60,22 @@ it('combines predicates under an AND logic', () => {
       .test({ id: 456, name: 'Kate' }),
   ).toBe(false)
 })
+
+it('supports a predicate function against an array property', () => {
+  const query = new Query<{ petNames: Array<string> }>().where({
+    petNames: (petNames) => petNames.includes('wolfy'),
+  })
+
+  expect(query.test({ petNames: ['wolfy'] })).toBe(true)
+  expect(query.test({ petNames: ['rex'] })).toBe(false)
+  expect(query.test({ petNames: [] })).toBe(false)
+})
+
+it('supports a condition against an array of objects', () => {
+  const query = new Query<{ posts: Array<{ title: string }> }>().where({
+    posts: { title: 'First' },
+  })
+
+  expect(query.test({ posts: [{ title: 'First' }] })).toBe(true)
+  expect(query.test({ posts: [{ title: 'Second' }] })).toBe(false)
+})