diff --git a/src/modules/list/commands.go b/src/modules/list/commands.go index 0a533cc..63c4fe6 100644 --- a/src/modules/list/commands.go +++ b/src/modules/list/commands.go @@ -19,22 +19,21 @@ func handleLLen(ctx context.Context, cmd []string, server utils.Server, conn *ne key := cmd[1] if !server.KeyExists(key) { - // Key, does not exist, return - return nil, errors.New("LLEN command on non-list item") + // If key does not exist, return 0 + return []byte(":0\r\n\r\n"), nil } _, err := server.KeyRLock(ctx, key) if err != nil { return nil, err } - list, ok := server.GetValue(key).([]interface{}) - server.KeyRUnlock(key) + defer server.KeyRUnlock(key) - if !ok { - return nil, errors.New("LLEN command on non-list item") + if list, ok := server.GetValue(key).([]interface{}); ok { + return []byte(fmt.Sprintf(":%d\r\n\r\n", len(list))), nil } - return []byte(fmt.Sprintf(":%d\r\n\r\n", len(list))), nil + return nil, errors.New("LLEN command on non-list item") } func handleLIndex(ctx context.Context, cmd []string, server utils.Server, conn *net.Conn) ([]byte, error) { diff --git a/src/modules/list/commands_test.go b/src/modules/list/commands_test.go index 2cdd824..acf9730 100644 --- a/src/modules/list/commands_test.go +++ b/src/modules/list/commands_test.go @@ -1 +1,96 @@ package list + +import ( + "bytes" + "context" + "errors" + "github.com/echovault/echovault/src/server" + "github.com/echovault/echovault/src/utils" + "github.com/tidwall/resp" + "testing" +) + +func Test_HandleLLEN(t *testing.T) { + mockServer := server.NewServer(server.Opts{}) + + tests := []struct { + preset bool + key string + presetValue interface{} + command []string + expectedResponse interface{} + expectedValue []interface{} + expectedError error + }{ + { // If key exists and is a list, return the lists length + preset: true, + key: "key1", + presetValue: []interface{}{"value1", "value2", "value3", "value4"}, + command: []string{"LLEN", "key1"}, + expectedResponse: 4, + expectedValue: nil, + expectedError: nil, + }, + { // If key does not exist, return 0 + preset: false, + key: "key2", + presetValue: nil, + command: []string{"LLEN", "key2"}, + expectedResponse: 0, + expectedValue: nil, + expectedError: nil, + }, + { // Command too short + preset: false, + key: "key3", + presetValue: nil, + command: []string{"LLEN"}, + expectedResponse: 0, + expectedValue: nil, + expectedError: errors.New(utils.WRONG_ARGS_RESPONSE), + }, + { // Command too long + preset: false, + key: "key4", + presetValue: nil, + command: []string{"LLEN", "key4", "key4"}, + expectedResponse: 0, + expectedValue: nil, + expectedError: errors.New(utils.WRONG_ARGS_RESPONSE), + }, + { // Trying to get lengths on a non-list returns error + preset: true, + key: "key5", + presetValue: "Default value", + command: []string{"LLEN", "key5"}, + expectedResponse: 0, + expectedValue: nil, + expectedError: errors.New("LLEN command on non-list item"), + }, + } + + 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 := handleLLen(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 + } + rd := resp.NewReader(bytes.NewBuffer(res)) + rv, _, err := rd.ReadValue() + if err != nil { + t.Error(err) + } + if rv.Integer() != test.expectedResponse { + t.Errorf("expected integer response \"%d\", got \"%d\"", test.expectedResponse, rv.Integer()) + } + } +}