enable object_name_linter and apply it (#634)

Co-authored-by: AshesITR <alexander.rosenstock@web.de>

.lintr

@@ -1,7 +1,6 @@
 linters: with_defaults( # The following TODOs are part of an effort to have {lintr} lint-free (#584)
    line_length_linter = line_length_linter(120),
    cyclocomp_linter = cyclocomp_linter(29), # TODO reduce to 15
-   object_name_linter = NULL, # TODO enable (#597)
    equals_na_linter = NULL, # TODO enable (#601)
    paren_brace_linter = NULL # TODO enable (#603)
  )

R/T_and_F_symbol_linter.R

@@ -2,7 +2,7 @@
 #'
 #' @describeIn linters  Avoid the symbols \code{T} and \code{F} (for \code{TRUE} and \code{FALSE}).
 #' @export
-T_and_F_symbol_linter <- function(source_file) {
+T_and_F_symbol_linter <- function(source_file) { # nolint: object_name_linter.
   lapply(
     ids_with_token(source_file, "SYMBOL"),
     function(id) {

R/equals_na_linter.R

@@ -8,11 +8,11 @@ equals_na_linter <- function(source_file) {
 
   comparators <- c("EQ", "NE")
   comparator_table <- paste0("self::", comparators, collapse = " or ")
-  NA_values <- c("NA", "NA_integer_", "NA_real_", "NA_complex_", "NA_character_")
-  NA_table <- paste("text() =", quote_wrap(NA_values, "'"), collapse = " or ")
+  na_values <- c("NA", "NA_integer_", "NA_real_", "NA_complex_", "NA_character_")
+  na_table <- paste("text() =", quote_wrap(na_values, "'"), collapse = " or ")
 
   xpath_fmt <- "//expr[expr[NUM_CONST[%s]]]/*[%s]"
-  xpath <- sprintf(xpath_fmt, NA_table, comparator_table)
+  xpath <- sprintf(xpath_fmt, na_table, comparator_table)
 
   bad_expr <- xml2::xml_find_all(xml, xpath)
 

R/lint.R

@@ -342,7 +342,8 @@ pkg_name <- function(path = find_package()) {
 #' @param ranges a list of ranges on the line that should be emphasized.
 #' @param linter name of linter that created the Lint object.
 #' @export
-Lint <- function(filename, line_number = 1L, column_number = 1L,
+Lint <- function( # nolint: object_name_linter.
+  filename, line_number = 1L, column_number = 1L,
   type = c("style", "warning", "error"),
   message = "", line = "", ranges = NULL, linter = "") {
 

R/utils.R

@@ -105,8 +105,9 @@ logical_env <- function(x) {
 # from ?chartr
 rot <- function(ch, k = 13) {
   p0 <- function(...) paste(c(...), collapse = "")
-  A <- c(letters, LETTERS, " '")
-  I <- seq_len(k); chartr(p0(A), p0(c(A[-I], A[I])), ch)
+  alphabet <- c(letters, LETTERS, " '")
+  idx <- seq_len(k)
+  chartr(p0(alphabet), p0(c(alphabet[-idx], alphabet[idx])), ch)
 }
 
 trim_ws <- function(x) {