From 68b2fb4ed72df8503e165f4b628eb21e13168902 Mon Sep 17 00:00:00 2001
From: Gerold Penz <gerold@halvar.at>
Date: Wed, 31 Jul 2024 15:08:57 +0200
Subject: [PATCH] incr and decr added

---
 src/index.ts         | 16 ++++++++++++++++
 tests/memory.test.ts | 37 +++++++++++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+)

diff --git a/src/index.ts b/src/index.ts
index c99f1d6..71bd631 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -471,4 +471,20 @@ export class BunSqliteKeyValue {
         })
     }
 
+
+    incr(key: string, incrBy: number = 1, ttlMs?: number): number {
+        const self = this
+        return this.db.transaction(() => {
+            const newValue = Number(self.get<number>(key) ?? 0) + incrBy
+            if (isNaN(newValue)) return NaN
+            self.set<number>(key, newValue, ttlMs)
+            return newValue
+        })()
+    }
+
+
+    decr(key: string, decrBy: number = 1, ttlMs?: number): number {
+        return this.incr(key, decrBy * -1, ttlMs)
+    }
+
 }
diff --git a/tests/memory.test.ts b/tests/memory.test.ts
index 110df21..de87e37 100644
--- a/tests/memory.test.ts
+++ b/tests/memory.test.ts
@@ -434,3 +434,40 @@ test("Proxy-Object (data, d): set, get and delete values", () => {
     expect(store.d.myKey2).toBeUndefined()
 })
 
+
+test("incr/decr", async () => {
+    const store = new BunSqliteKeyValue()
+
+    // incr/decr
+    const resultArray = [
+        store.incr(KEY_1), store.incr(KEY_1),
+        store.decr(KEY_1), store.decr(KEY_1),
+    ]
+    expect(resultArray).toEqual([1, 2, 1, 0])
+    store.delete(KEY_1)
+
+    // ttlMs
+    store.incr(KEY_1, 1, 30)
+    await Bun.sleep(40)
+    expect(store.incr(KEY_1, 1)).toEqual(1)
+    store.delete(KEY_1)
+
+    // incrBy/decrBy
+    store.incr(KEY_1, 2)
+    expect(store.incr(KEY_1, 2)).toEqual(4)
+    expect(store.incr(KEY_1, -2)).toEqual(2)
+    expect(store.decr(KEY_1, 1)).toEqual(1)
+    expect(store.decr(KEY_1, -1)).toEqual(2)
+
+    // String with number
+    store.set(KEY_1, "100")
+    expect(store.incr(KEY_1)).toEqual(101)
+
+    // NaN
+    const value: string = "I am no number"
+    store.set<string>(KEY_1, value)
+    expect(store.incr(KEY_1)).toBeNaN()
+    expect(store.get<string>(KEY_1)).toEqual(value)
+
+})
+