fix: allow empty string in $contains (#2179)

playground/basic/content/1.real-content/post.md

@@ -0,0 +1,8 @@
+---
+title: Post 1
+authors: [ "alice", "bob" ]
+---
+
+# Post 1
+
+This is the first post written by Alice and Bob used to try `$contains` filter.

playground/basic/pages/custom-query.vue

@@ -0,0 +1,9 @@
+<script lang="ts" setup>
+const { data } = await useAsyncData('posts', () => queryContent('/real-content/post').where({ authors: { $contains: '' } }).find())
+</script>
+
+<template>
+  <div>
+    {{ data }}
+  </div>
+</template>

src/runtime/query/match/utils.ts

@@ -101,5 +101,6 @@ export const assertArray = (value: any, message = 'Expected an array') => {
 /**
  * Ensure result is an array
  */
-export const ensureArray = <T>(value: T) =>
-(Array.isArray(value) ? value : value ? [value] : []) as T extends Array<any> ? T : T[]
+export const ensureArray = <T>(value: T) => {
+  return (Array.isArray(value) ? value : [undefined, null].includes(value as any) ? [] : [value]) as T extends Array<any> ? T : T[]
+}

test/features/query/match.test.ts

@@ -23,6 +23,10 @@ describe('Match', () => {
 
       // match multiple conditions
       expect(match(item, { 'nested.users.0': { $contains: ['Maha', 'tma'] } })).toBe(true)
+
+      expect(match({ values: [0, false, ''] }, { values: { $contains: '' } })).toBe(true)
+      expect(match({ values: [0, false, ''] }, { values: { $contains: 0 } })).toBe(true)
+      expect(match({ values: [0, false, ''] }, { values: { $contains: false } })).toBe(true)
     })
 
     test('$icontains string', () => {
@@ -38,6 +42,11 @@ describe('Match', () => {
       expect(match(item, { 'nested.users': { $contains: ['Woodrow', 'Steve'] } })).toBe(true)
       expect(match(item, { 'nested.users': { $contains: ['Woodrow', 'Steve', 'Mahatma'] } })).toBe(true)
       expect(match(item, { 'nested.users': { $contains: ['Woodrow', 'Steve', 'Mahatma', 'John'] } })).toBe(false)
+      expect(match(item, { 'nested.users': { $contains: '' } })).toBe(false)
+      expect(match(item, { 'nested.users': { $contains: 0 } })).toBe(false)
+      expect(match(item, { 'nested.users': { $contains: false } })).toBe(false)
+      expect(match(item, { 'nested.users': { $contains: null } })).toBe(true)
+      expect(match(item, { 'nested.users': { $contains: undefined } })).toBe(true)
     })
 
     test('$containsAny', () => {