From 96ec9c808beee4be9ef3bbd36aebe4be58761e71 Mon Sep 17 00:00:00 2001
From: typicode <typicode@gmail.com>
Date: Wed, 18 Feb 2026 00:54:32 +0100
Subject: [PATCH] feat: add in operator for where filters

---
 src/matches-where.test.ts |  6 ++++++
 src/matches-where.ts      |  4 ++++
 src/parse-where.test.ts   | 12 ++++++++++++
 src/parse-where.ts        |  9 +++++++++
 src/where-operators.ts    |  2 +-
 5 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/src/matches-where.test.ts b/src/matches-where.test.ts
index 66f00dc..c3fb9e7 100644
--- a/src/matches-where.test.ts
+++ b/src/matches-where.test.ts
@@ -26,6 +26,12 @@ await test('matchesWhere', async (t) => {
     [{ or: [{ a: { lt: 0 } }, { b: { gt: 20 } }] }, false],
     [{ nested: { a: { eq: 10 } } }, true],
     [{ nested: { b: { lt: 20 } } }, false],
+    [{ a: { in: [10, 11] } }, true],
+    [{ a: { in: [1, 2] } }, false],
+    [{ c: { in: ['x', 'y'] } }, true],
+    [{ c: { in: ['y', 'z'] } }, false],
+    [{ a: { in: [10, 11], gt: 9 } }, true],
+    [{ a: { in: [10, 11], gt: 10 } }, false],
     [{ a: { foo: 10 } }, true],
     [{ a: { foo: 10, eq: 10 } }, true],
     [{ missing: { foo: 1 } }, true],
diff --git a/src/matches-where.ts b/src/matches-where.ts
index 07a7e7d..8a1da62 100644
--- a/src/matches-where.ts
+++ b/src/matches-where.ts
@@ -53,6 +53,10 @@ export function matchesWhere(obj: JsonObject, where: JsonObject): boolean {
         if (knownOps.includes('gte') && !((field as any) >= (op.gte as any))) return false
         if (knownOps.includes('eq') && !((field as any) === (op.eq as any))) return false
         if (knownOps.includes('ne') && !((field as any) !== (op.ne as any))) return false
+        if (knownOps.includes('in')) {
+          const inValues = Array.isArray(op.in) ? op.in : [op.in]
+          if (!inValues.some((v) => (field as any) === (v as any))) return false
+        }
         continue
       }
 
diff --git a/src/parse-where.test.ts b/src/parse-where.test.ts
index 2bf0f89..a2d46d8 100644
--- a/src/parse-where.test.ts
+++ b/src/parse-where.test.ts
@@ -83,6 +83,18 @@ await test('parseWhere', async (t) => {
         views: { gt: 100, lt: 300 },
       },
     ],
+    [
+      'id:in=1,3',
+      {
+        id: { in: [1, 3] },
+      },
+    ],
+    [
+      'title_in=hello,world',
+      {
+        title: { in: ['hello', 'world'] },
+      },
+    ],
   ]
 
   for (const [query, expected] of cases) {
diff --git a/src/parse-where.ts b/src/parse-where.ts
index ffde648..06b3bc6 100644
--- a/src/parse-where.ts
+++ b/src/parse-where.ts
@@ -30,6 +30,15 @@ function splitKey(key: string): { path: string; op: WhereOperator | null } {
 
 function setPathOp(root: JsonObject, path: string, op: WhereOperator, value: string): void {
   const fullPath = `${path}.${op}`
+  if (op === 'in') {
+    setProperty(
+      root,
+      fullPath,
+      value.split(',').map((part) => coerceValue(part.trim())),
+    )
+    return
+  }
+
   setProperty(root, fullPath, coerceValue(value))
 }
 
diff --git a/src/where-operators.ts b/src/where-operators.ts
index ec31a04..f522931 100644
--- a/src/where-operators.ts
+++ b/src/where-operators.ts
@@ -1,4 +1,4 @@
-export const WHERE_OPERATORS = ['lt', 'lte', 'gt', 'gte', 'eq', 'ne'] as const
+export const WHERE_OPERATORS = ['lt', 'lte', 'gt', 'gte', 'eq', 'ne', 'in'] as const
 
 export type WhereOperator = (typeof WHERE_OPERATORS)[number]