feat: handle GT and LT options in ZADD.

src/commands/zadd.js

@@ -1,7 +1,7 @@
 export function zadd(key, ...vals) {
   // consume options
   const options = []
-  while (['NX', 'XX', 'CH', 'INCR'].includes(vals[0])) {
+  while (['NX', 'XX', 'GT', 'LT', 'CH', 'INCR'].includes(vals[0])) {
     options.push(vals.shift())
   }
 
@@ -12,12 +12,16 @@ export function zadd(key, ...vals) {
   // set option vals
   const nx = options.includes('NX')
   const xx = options.includes('XX')
+  const gt = options.includes('GT')
+  const lt = options.includes('LT')
   const ch = options.includes('CH')
   const incr = options.includes('INCR')
 
   // validate options
   if (nx && xx)
     throw new Error('XX and NX options at the same time are not compatible')
+  if (gt && lt)
+    throw new Error('GT and LT options at the same time are not compatible')
   if (incr && elems > 2)
     throw new Error('INCR option supports a single increment-element pair')
 
@@ -36,8 +40,13 @@ export function zadd(key, ...vals) {
 
     if (map.has(value)) {
       if (!nx) {
+        const exist = map.get(value)
         if (incr) {
-          score += Number(map.get(value).score)
+          score += Number(exist.score)
+        }
+        // eslint-ignore-next-line
+        if (lt && score >= exist.score || gt && score <= exist.score) {
+          continue
         }
         map.set(value, { score, value })
         updated++

test/integration/commands/zadd.js

@@ -34,6 +34,11 @@ runTwinSuite('zadd', command => {
         redis[command]('key', ['NX', 'XX'], 1, 'value')
       ).rejects.toThrow('not compatible')
     })
+    it('should not allow GT and LT options in the same call', async () => {
+      await expect(
+        redis[command]('key', ['GT', 'LT'], 1, 'value')
+      ).rejects.toThrow('not compatible')
+    })
     it('should not update a value that exists with NX option', async () => {
       await redis[command]('key', 'NX', 1, 'value')
       expect(await redis[command]('key', 'NX', 2, 'value')).toBe(0)
@@ -46,6 +51,42 @@ runTwinSuite('zadd', command => {
       await redis[command]('key', 1, 'value')
       expect(await redis[command]('key', ['XX', 'CH'], 2, 'value')).toBe(1)
     })
+    it('should not update a value with equal or lower score with LT option', async () => {
+      await redis[command]('key', 'LT', 2, 'value')
+      expect(await redis[command]('key', ['LT', 'CH'], 2, 'value')).toBe(0)
+      expect(await redis[command]('key', ['LT', 'CH'], 3, 'value')).toBe(0)
+      expect(await redis[command]('key', ['LT', 'CH'], 1, 'value')).toBe(1)
+    })
+    it('should not update a value with equal or higher score with GT option', async () => {
+      await redis[command]('key', 'GT', 2, 'value')
+      expect(await redis[command]('key', ['GT', 'CH'], 2, 'value')).toBe(0)
+      expect(await redis[command]('key', ['GT', 'CH'], 1, 'value')).toBe(0)
+      expect(await redis[command]('key', ['GT', 'CH'], 3, 'value')).toBe(1)
+    })
+    it('should handle INCR and LT option', async () => {
+      await redis[command]('key', 2, 'value')
+      // LT + INCR w/ non-negative should never work
+      expect(await redis[command]('key', ['LT', 'CH', 'INCR'], 0, 'value')).toBe(0)
+      expect(await redis[command]('key', ['LT', 'CH', 'INCR'], -2, 'value')).toBe(1)
+      expect(await redis.zrange('key', 0, -1, 'WITHSCORES')).toEqual([
+        'value',
+        '0',
+      ])
+    })
+    it('should handle INCR and GT option', async () => {
+      await redis[command]('key', 2, 'value')
+      expect(await redis[command]('key', ['GT', 'CH', 'INCR'], 2, 'value')).toBe(1)
+      expect(await redis.zrange('key', 0, -1, 'WITHSCORES')).toEqual([
+        'value',
+        '4',
+      ])
+      // should work even if specified score is lower
+      expect(await redis[command]('key', ['GT', 'CH', 'INCR'], 1, 'value')).toBe(1)
+      expect(await redis.zrange('key', 0, -1, 'WITHSCORES')).toEqual([
+        'value',
+        '4',
+      ])
+    })
     it('should handle INCR option', async () => {
       await redis[command]('key', 1, 'value')
       await redis[command]('key', 'INCR', 2, 'value')