From 9da41c8a37d9c49ee4a16d5bd520fd6ae01c14ec Mon Sep 17 00:00:00 2001
From: Martin Schuster <mastodon0@users.noreply.github.com>
Date: Fri, 28 Jan 2022 15:43:38 +0100
Subject: [PATCH] fix: where-filter null handling (#457)

---
 src/builtin/filters/array.ts              |  5 ++++-
 test/integration/builtin/filters/array.ts | 12 ++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/builtin/filters/array.ts b/src/builtin/filters/array.ts
index 5da7b201d..ade6e1128 100644
--- a/src/builtin/filters/array.ts
+++ b/src/builtin/filters/array.ts
@@ -3,6 +3,7 @@ import { toArray } from '../../util/collection'
 import { isTruthy } from '../../render/boolean'
 import { FilterImpl } from '../../template/filter/filter-impl'
 import { Scope } from '../../context/scope'
+import { isComparable } from '../../drop/comparable'
 
 export const join = (v: any[], arg: string) => v.join(arg === undefined ? ' ' : arg)
 export const last = (v: any) => isArray(v) ? arrayLast(v) : ''
@@ -40,7 +41,9 @@ export function slice<T> (v: T[], begin: number, length = 1): T[] {
 export function where<T extends object> (this: FilterImpl, arr: T[], property: string, expected?: any): T[] {
   return toArray(arr).filter(obj => {
     const value = this.context.getFromScope(obj, String(property).split('.'))
-    return expected === undefined ? isTruthy(value, this.context) : value === expected
+    if (expected === undefined) return isTruthy(value, this.context)
+    if (isComparable(expected)) return expected.equals(value)
+    return value === expected
   })
 }
 
diff --git a/test/integration/builtin/filters/array.ts b/test/integration/builtin/filters/array.ts
index 8563c18c1..3561eb329 100644
--- a/test/integration/builtin/filters/array.ts
+++ b/test/integration/builtin/filters/array.ts
@@ -183,6 +183,18 @@ describe('filters/array', function () {
         - Boring sneakers
         `)
     })
+    it('should support filter by null property', function () {
+      return test(`{% assign untyped_products = products | where: "type", null %}
+        Untyped products:
+        {% for product in untyped_products -%}
+        - {{ product.title }}
+        {% endfor %}`, { products }, `
+        Untyped products:
+        - Coffee mug
+        - Limited edition sneakers
+        - Boring sneakers
+        `)
+    })
     it('should support nested property', async function () {
       const authors = [
         { name: 'Alice', books: { year: 2019 } },