Implemented test for ZCOUNT command handler

src/modules/sorted_set/commands.go

@@ -187,11 +187,12 @@ func handleZCARD(ctx context.Context, cmd []string, server utils.Server, conn *n
 }
 
 func handleZCOUNT(ctx context.Context, cmd []string, server utils.Server, conn *net.Conn) ([]byte, error) {
-	if len(cmd) != 4 {
+	keys, err := zcountKeyFunc(cmd)
-		return nil, errors.New(utils.WRONG_ARGS_RESPONSE)
+	if err != nil {
+		return nil, err
 	}
 
-	key := cmd[1]
+	key := keys[0]
 
 	minimum := Score(math.Inf(-1))
 	switch utils.AdaptType(cmd[2]).(type) {
@@ -230,11 +231,10 @@ func handleZCOUNT(ctx context.Context, cmd []string, server utils.Server, conn *
 	}
 
 	if !server.KeyExists(key) {
-		return []byte("*0\r\n\r\n"), nil
+		return []byte(":0\r\n\r\n"), nil
 	}
 
-	_, err := server.KeyRLock(ctx, key)
+	if _, err = server.KeyRLock(ctx, key); err != nil {
-	if err != nil {
 		return nil, err
 	}
 	defer server.KeyRUnlock(key)
@@ -1577,9 +1577,11 @@ Adds all the specified members with the specified scores to the sorted set at th
 			HandlerFunc:       handleZADD,
 		},
 		{
-			Command:           "zcard",
+			Command:    "zcard",
-			Categories:        []string{utils.SortedSetCategory, utils.ReadCategory, utils.SlowCategory},
+			Categories: []string{utils.SortedSetCategory, utils.ReadCategory, utils.SlowCategory},
-			Description:       `(ZCARD key) Returns the set cardinality of the sorted set at key.`,
+			Description: `(ZCARD key) Returns the set cardinality of the sorted set at key.
+If the key does not exist, 0 is returned, otherwise the cardinality of the sorted set is returned.
+If the key holds a value that is not a sorted set, this command will return an error.`,
 			Sync:              false,
 			KeyExtractionFunc: zcardKeyFunc,
 			HandlerFunc:       handleZCARD,
@@ -1588,7 +1590,9 @@ Adds all the specified members with the specified scores to the sorted set at th
 			Command:    "zcount",
 			Categories: []string{utils.SortedSetCategory, utils.ReadCategory, utils.SlowCategory},
 			Description: `(ZCOUNT key min max) 
-Returns the number of elements in the sorted set key with scores in the range of min and max.`,
+Returns the number of elements in the sorted set key with scores in the range of min and max.
+If the key does not exist, a count of 0 is returned, otherwise return the count.
+If the key holds a value that is not a sorted set, an error is returned.`,
 			Sync:              false,
 			KeyExtractionFunc: zcountKeyFunc,
 			HandlerFunc:       handleZCOUNT,

src/modules/sorted_set/commands_test.go

@@ -349,7 +349,135 @@ func Test_HandleZCARD(t *testing.T) {
 	}
 }
 
-func Test_HandleZCOUNT(t *testing.T) {}
+func Test_HandleZCOUNT(t *testing.T) {
+	mockServer := server.NewServer(server.Opts{})
+
+	tests := []struct {
+		preset           bool
+		presetValue      *SortedSet
+		key              string
+		command          []string
+		expectedValue    *SortedSet
+		expectedResponse int
+		expectedError    error
+	}{
+		{ // 1. Get entire count using infinity boundaries
+			preset: true,
+			presetValue: NewSortedSet([]MemberParam{
+				{value: "member1", score: Score(5.5)},
+				{value: "member2", score: Score(67.77)},
+				{value: "member3", score: Score(10)},
+				{value: "member4", score: Score(1083.13)},
+				{value: "member5", score: Score(11)},
+				{value: "member6", score: Score(math.Inf(-1))},
+				{value: "member7", score: Score(math.Inf(1))},
+			}),
+			key:              "key1",
+			command:          []string{"ZCOUNT", "key1", "-inf", "+inf"},
+			expectedValue:    nil,
+			expectedResponse: 7,
+			expectedError:    nil,
+		},
+		{ // 2. Get count of sub-set from -inf to limit
+			preset: true,
+			presetValue: NewSortedSet([]MemberParam{
+				{value: "member1", score: Score(5.5)},
+				{value: "member2", score: Score(67.77)},
+				{value: "member3", score: Score(10)},
+				{value: "member4", score: Score(1083.13)},
+				{value: "member5", score: Score(11)},
+				{value: "member6", score: Score(math.Inf(-1))},
+				{value: "member7", score: Score(math.Inf(1))},
+			}),
+			key:              "key2",
+			command:          []string{"ZCOUNT", "key2", "-inf", "90"},
+			expectedValue:    nil,
+			expectedResponse: 5,
+			expectedError:    nil,
+		},
+		{ // 3. Get count of sub-set from bottom boundary to +inf limit
+			preset: true,
+			presetValue: NewSortedSet([]MemberParam{
+				{value: "member1", score: Score(5.5)},
+				{value: "member2", score: Score(67.77)},
+				{value: "member3", score: Score(10)},
+				{value: "member4", score: Score(1083.13)},
+				{value: "member5", score: Score(11)},
+				{value: "member6", score: Score(math.Inf(-1))},
+				{value: "member7", score: Score(math.Inf(1))},
+			}),
+			key:              "key3",
+			command:          []string{"ZCOUNT", "key3", "1000", "+inf"},
+			expectedValue:    nil,
+			expectedResponse: 2,
+			expectedError:    nil,
+		},
+		{ // 4. Return error when bottom boundary is not a valid double/float
+			preset:           false,
+			presetValue:      nil,
+			key:              "key4",
+			command:          []string{"ZCOUNT", "key4", "min", "10"},
+			expectedValue:    nil,
+			expectedResponse: 0,
+			expectedError:    errors.New("min constraint must be a double"),
+		},
+		{ // 5. Return error when top boundary is not a valid double/float
+			preset:           false,
+			presetValue:      nil,
+			key:              "key5",
+			command:          []string{"ZCOUNT", "key5", "-10", "max"},
+			expectedValue:    nil,
+			expectedResponse: 0,
+			expectedError:    errors.New("max constraint must be a double"),
+		},
+		{ // 6. Command is too short
+			preset:           false,
+			presetValue:      nil,
+			key:              "key6",
+			command:          []string{"ZCOUNT"},
+			expectedValue:    nil,
+			expectedResponse: 0,
+			expectedError:    errors.New(utils.WRONG_ARGS_RESPONSE),
+		},
+		{ // 7. Command too long
+			preset:           false,
+			presetValue:      nil,
+			key:              "key7",
+			command:          []string{"ZCOUNT", "key4", "min", "max", "count"},
+			expectedValue:    nil,
+			expectedResponse: 0,
+			expectedError:    errors.New(utils.WRONG_ARGS_RESPONSE),
+		},
+	}
+
+	for _, test := range tests {
+		if test.preset {
+			if _, err := mockServer.CreateKeyAndLock(context.Background(), test.key); err != nil {
+				t.Error(err)
+			}
+			mockServer.SetValue(context.Background(), test.key, test.presetValue)
+			mockServer.KeyUnlock(test.key)
+		}
+		res, err := handleZCOUNT(context.Background(), test.command, mockServer, nil)
+		if test.expectedError != nil {
+			if err.Error() != test.expectedError.Error() {
+				t.Errorf("expected error \"%s\", got \"%s\"", test.expectedError.Error(), err.Error())
+			}
+			continue
+		}
+		if err != nil {
+			t.Error(err)
+		}
+		rd := resp.NewReader(bytes.NewReader(res))
+		rv, _, err := rd.ReadValue()
+		if err != nil {
+			t.Error(err)
+		}
+		if rv.Integer() != test.expectedResponse {
+			t.Errorf("expected response %d at key \"%s\", got %d", test.expectedResponse, test.key, rv.Integer())
+		}
+	}
+}
 
 func Test_HandleZLEXCOUNT(t *testing.T) {}