diff --git a/R/categorize.R b/R/categorize.R
index 0df7edd4c..d440069d8 100644
--- a/R/categorize.R
+++ b/R/categorize.R
@@ -192,11 +192,11 @@ categorize.numeric <- function(x,
     breaks <- split
   } else {
     breaks <- switch(split,
-      "median" = stats::median(x),
-      "mean" = mean(x),
-      "length" = n_groups,
-      "quantile" = stats::quantile(x, probs = seq_len(n_groups) / n_groups),
-      "range" = .equal_range(x, range, n_groups, lowest),
+      median = stats::median(x),
+      mean = mean(x),
+      length = n_groups,
+      quantile = stats::quantile(x, probs = seq_len(n_groups) / n_groups),
+      range = .equal_range(x, range, n_groups, lowest),
       NULL
     )
   }
diff --git a/R/data_codebook.R b/R/data_codebook.R
index 077dfd6d5..7608f08d5 100644
--- a/R/data_codebook.R
+++ b/R/data_codebook.R
@@ -456,8 +456,14 @@ print_md.data_codebook <- function(x, ...) {
   # need to remove this one
   x$Prop <- NULL
   align <- c(
-    "ID" = "l", "Name" = "l", "Label" = "l", "Type" = "l", "Missings" = "r",
-    "Values" = "r", "Value Labels" = "l", "N" = "r"
+    ID = "l",
+    Name = "l",
+    Label = "l",
+    Type = "l",
+    Missings = "r",
+    Values = "r",
+    `Value Labels` = "l",
+    N = "r"
   )
   align <- align[colnames(x)]
   paste0(unname(align), collapse = "")
diff --git a/R/data_extract.R b/R/data_extract.R
index df38dcbde..b5613309c 100644
--- a/R/data_extract.R
+++ b/R/data_extract.R
@@ -114,10 +114,10 @@ data_extract.data.frame <- function(data,
 
   # chose which matched variables to extract
   select <- switch(extract,
-    "first" = select[1L],
-    "last" = select[length(select)],
-    "odd" = select[seq(1L, length(select), 2L)],
-    "even" = select[seq(2L, length(select), 2L)],
+    first = select[1L],
+    last = select[length(select)],
+    odd = select[seq(1L, length(select), 2L)],
+    even = select[seq(2L, length(select), 2L)],
     select
   )
 
diff --git a/R/data_match.R b/R/data_match.R
index ff567d952..7c19c7911 100644
--- a/R/data_match.R
+++ b/R/data_match.R
@@ -109,17 +109,17 @@ data_match <- function(x, to, match = "and", return_indices = FALSE, drop_na = T
   # evaluate
   match <- match.arg(tolower(match), c("and", "&", "&&", "or", "|", "||", "!", "not"))
   match <- switch(match,
-    "&" = ,
-    "&&" = ,
-    "and" = "and",
-    "!" = ,
-    "not" = "not",
+    `&` = ,
+    `&&` = ,
+    and = "and",
+    `!` = ,
+    not = "not",
     "or"
   )
 
   # validation check
   shared_columns <- intersect(colnames(x), colnames(to))
-  if (is.null(shared_columns) || length(shared_columns) == 0) {
+  if (is.null(shared_columns) || length(shared_columns) == 0L) {
     insight::format_error(
       "None of the columns from the data frame with matching conditions were found in `x`."
     )
@@ -277,7 +277,6 @@ data_filter.data.frame <- function(x, ...) {
 
 #' @export
 data_filter.grouped_df <- function(x, ...) {
-  # works only for dplyr >= 0.8.0
   grps <- attr(x, "groups", exact = TRUE)
   grps <- grps[[".rows"]]
 
diff --git a/R/data_merge.R b/R/data_merge.R
index c8a90cb0e..58be12f8a 100644
--- a/R/data_merge.R
+++ b/R/data_merge.R
@@ -274,13 +274,13 @@ data_merge.data.frame <- function(x, y, join = "left", by = NULL, id = NULL, ver
   all_columns <- union(colnames(x), colnames(y))
 
   out <- switch(join,
-    "full" = merge(x, y, all = TRUE, sort = FALSE, by = by),
-    "left" = merge(x, y, all.x = TRUE, sort = FALSE, by = by),
-    "right" = merge(x, y, all.y = TRUE, sort = FALSE, by = by),
-    "inner" = merge(x, y, sort = FALSE, by = by),
-    "semi" = x[x[[by]] %in% y[[by]], , drop = FALSE],
-    "anti" = x[!x[[by]] %in% y[[by]], , drop = FALSE],
-    "bind" = .bind_data_frames(x, y)
+    full = merge(x, y, all = TRUE, sort = FALSE, by = by),
+    left = merge(x, y, all.x = TRUE, sort = FALSE, by = by),
+    right = merge(x, y, all.y = TRUE, sort = FALSE, by = by),
+    inner = merge(x, y, sort = FALSE, by = by),
+    semi = x[x[[by]] %in% y[[by]], , drop = FALSE],
+    anti = x[!x[[by]] %in% y[[by]], , drop = FALSE],
+    bind = .bind_data_frames(x, y)
   )
 
 
diff --git a/R/data_read.R b/R/data_read.R
index 2c3061570..a2f3b46d9 100644
--- a/R/data_read.R
+++ b/R/data_read.R
@@ -97,14 +97,14 @@ data_read <- function(path,
 
   # read data
   out <- switch(file_type,
-    "txt" = ,
-    "csv" = .read_text(path, encoding, verbose, ...),
-    "xls" = ,
-    "xlsx" = .read_excel(path, encoding, verbose, ...),
-    "sav" = ,
-    "por" = .read_spss(path, encoding, convert_factors, verbose, ...),
-    "dta" = .read_stata(path, encoding, convert_factors, verbose, ...),
-    "sas7bdat" = .read_sas(path, path_catalog, encoding, convert_factors, verbose, ...),
+    txt = ,
+    csv = .read_text(path, encoding, verbose, ...),
+    xls = ,
+    xlsx = .read_excel(path, encoding, verbose, ...),
+    sav = ,
+    por = .read_spss(path, encoding, convert_factors, verbose, ...),
+    dta = .read_stata(path, encoding, convert_factors, verbose, ...),
+    sas7bdat = .read_sas(path, path_catalog, encoding, convert_factors, verbose, ...),
     .read_unknown(path, convert_factors, verbose, ...)
   )
 
diff --git a/R/data_separate.R b/R/data_separate.R
index eb6d571f1..c5e83183d 100644
--- a/R/data_separate.R
+++ b/R/data_separate.R
@@ -229,9 +229,9 @@ data_separate <- function(data,
       l <- l[!vapply(l, function(i) all(is.na(i)), TRUE)]
       # define number of new columns, based on user-choice
       n_cols <- switch(guess_columns,
-        "min" = min(l, na.rm = TRUE),
-        "max" = max(l, na.rm = TRUE),
-        "mode" = distribution_mode(l),
+        min = min(l, na.rm = TRUE),
+        max = max(l, na.rm = TRUE),
+        mode = distribution_mode(l),
       )
       # tell user
       if (verbose && insight::n_unique(l) != 1 && !is.numeric(separator)) {
@@ -374,10 +374,10 @@ data_separate <- function(data,
         "`", sep_column, "`",
         " returned more columns than expected after splitting. ",
         switch(extra,
-          "drop_left" = "Left-most columns have been dropped.",
-          "drop_right" = "Right-most columns have been dropped.",
-          "merge_left" = "Left-most columns have been merged together.",
-          "merge_right" = "Right-most columns have been merged together."
+          drop_left = "Left-most columns have been dropped.",
+          drop_right = "Right-most columns have been dropped.",
+          merge_left = "Left-most columns have been merged together.",
+          merge_right = "Right-most columns have been merged together."
         )
       ))
     }
@@ -386,10 +386,10 @@ data_separate <- function(data,
         "`", sep_column, "`",
         "returned fewer columns than expected after splitting. ",
         switch(fill,
-          "left" = "Left-most columns were filled with `NA`.",
-          "right" = "Right-most columns were filled with `NA`.",
-          "value_left" = "Left-most columns were filled with first value.",
-          "value_right" = "Right-most columns were filled with last value."
+          left = "Left-most columns were filled with `NA`.",
+          right = "Right-most columns were filled with `NA`.",
+          value_left = "Left-most columns were filled with first value.",
+          value_right = "Right-most columns were filled with last value."
         )
       ))
     }
diff --git a/R/data_tabulate.R b/R/data_tabulate.R
index 71b694eb8..3b16932a3 100644
--- a/R/data_tabulate.R
+++ b/R/data_tabulate.R
@@ -489,14 +489,14 @@ print_md.dw_data_tabulates <- function(x, big_mark = NULL, ...) {
   }
 
   switch(vt,
-    "ord" = "ordinal",
-    "fct" = "categorical",
-    "dbl" = "numeric",
-    "int" = "integer",
-    "chr" = "character",
-    "lbl" = "labelled",
-    "cpl" = "complex",
-    "lgl" = "logical",
+    ord = "ordinal",
+    fct = "categorical",
+    dbl = "numeric",
+    int = "integer",
+    chr = "character",
+    lbl = "labelled",
+    cpl = "complex",
+    lgl = "logical",
     vt
   )
 }
diff --git a/R/data_write.R b/R/data_write.R
index 324b71168..7e4e543d6 100644
--- a/R/data_write.R
+++ b/R/data_write.R
@@ -19,13 +19,13 @@ data_write <- function(data,
   # check file type, so we know the target dta format
   file_type <- .file_ext(path)
   type <- switch(file_type,
-    "txt" = ,
-    "csv" = "csv",
-    "sav" = ,
-    "por" = "spss",
-    "zsav" = "zspss",
-    "dta" = "stata",
-    "xpt" = "sas",
+    txt = ,
+    csv = "csv",
+    sav = ,
+    por = "spss",
+    zsav = "zspss",
+    dta = "stata",
+    xpt = "sas",
     "unknown"
   )
 
diff --git a/R/describe_distribution.R b/R/describe_distribution.R
index e01243388..00a8a2475 100644
--- a/R/describe_distribution.R
+++ b/R/describe_distribution.R
@@ -230,7 +230,7 @@ describe_distribution.numeric <- function(x,
 
   out$n <- length(x)
   out$n_Missing <- n_missing
-  out$`.temp` <- NULL
+  out$.temp <- NULL
 
   class(out) <- unique(c("parameters_distribution", "see_parameters_distribution", class(out)))
   attr(out, "data") <- x
diff --git a/R/select_nse.R b/R/select_nse.R
index 8d312f7b1..118d40b15 100644
--- a/R/select_nse.R
+++ b/R/select_nse.R
@@ -96,11 +96,11 @@
   type <- typeof(x)
 
   out <- switch(type,
-    "integer" = x,
-    "double" = as.integer(x),
-    "character" = .select_char(data, x, ignore_case, regex = regex, verbose),
-    "symbol" = .select_symbol(data, x, ignore_case, regex = regex, verbose),
-    "language" = .eval_call(data, x, ignore_case, regex = regex, verbose),
+    integer = x,
+    double = as.integer(x),
+    character = .select_char(data, x, ignore_case, regex = regex, verbose),
+    symbol = .select_symbol(data, x, ignore_case, regex = regex, verbose),
+    language = .eval_call(data, x, ignore_case, regex = regex, verbose),
     insight::format_error(paste0(
       "Expressions of type <", typeof(x),
       "> cannot be evaluated for use when subsetting."
@@ -254,13 +254,13 @@
     `[` = .select_square_bracket(x, data, ignore_case, regex, verbose),
     `$` = .select_dollar(x, data, ignore_case, regex, verbose),
     `~` = .select_tilde(x, data, ignore_case, regex, verbose),
-    "list" = .select_list(x, data, ignore_case, regex, verbose),
-    "names" = .select_names(x, data, ignore_case, regex, verbose),
-    "starts_with" = ,
-    "ends_with" = ,
-    "matches" = ,
-    "contains" = ,
-    "regex" = .select_helper(x, data, ignore_case, regex, verbose),
+    list = .select_list(x, data, ignore_case, regex, verbose),
+    names = .select_names(x, data, ignore_case, regex, verbose),
+    starts_with = ,
+    ends_with = ,
+    matches = ,
+    contains = ,
+    regex = .select_helper(x, data, ignore_case, regex, verbose),
     .select_context(x, data, ignore_case, regex, verbose)
   )
 }
@@ -369,10 +369,10 @@
   helper <- insight::safe_deparse(lst_expr[[1]])
 
   rgx <- switch(helper,
-    "starts_with" = paste0("^(", collapsed_patterns, ")"),
-    "ends_with" = paste0("(", collapsed_patterns, ")$"),
-    "contains" = paste0("(", collapsed_patterns, ")"),
-    "regex" = collapsed_patterns,
+    starts_with = paste0("^(", collapsed_patterns, ")"),
+    ends_with = paste0("(", collapsed_patterns, ")$"),
+    contains = paste0("(", collapsed_patterns, ")"),
+    regex = collapsed_patterns,
     insight::format_error("There is no select helper called '", helper, "'.")
   )
   grep(rgx, colnames(data), ignore.case = ignore_case)
diff --git a/R/skewness_kurtosis.R b/R/skewness_kurtosis.R
index 13ad4e422..e0da83c54 100644
--- a/R/skewness_kurtosis.R
+++ b/R/skewness_kurtosis.R
@@ -474,16 +474,16 @@ summary.parameters_kurtosis <- function(object, test = FALSE, ...) {
   }
 
   switch(type,
-    "1" = ,
-    "I" = ,
-    "classic" = "1",
-    "2" = ,
-    "II" = ,
-    "SPSS" = ,
-    "SAS" = "2",
-    "3" = ,
-    "III" = ,
-    "Minitab" = "3"
+    `1` = ,
+    I = ,
+    classic = "1",
+    `2` = ,
+    II = ,
+    SPSS = ,
+    SAS = "2",
+    `3` = ,
+    III = ,
+    Minitab = "3"
   )
 }
 
diff --git a/tests/testthat/test-assign_labels.R b/tests/testthat/test-assign_labels.R
index fd74705ef..300ae643f 100644
--- a/tests/testthat/test-assign_labels.R
+++ b/tests/testthat/test-assign_labels.R
@@ -16,7 +16,7 @@ test_that("assign_labels, named values", {
   out <- assign_labels(
     x,
     variable = "Labelled factor",
-    values = c(`a` = "low", `b` = "mid", `c` = "high")
+    values = c(a = "low", b = "mid", c = "high")
   )
   expect_identical(attributes(out)$label, "Labelled factor")
   expect_identical(attributes(out)$labels, c(low = "a", mid = "b", high = "c"))
diff --git a/tests/testthat/test-data_codebook.R b/tests/testthat/test-data_codebook.R
index daaf1f77b..26a67ccf6 100644
--- a/tests/testthat/test-data_codebook.R
+++ b/tests/testthat/test-data_codebook.R
@@ -159,9 +159,11 @@ test_that("data_codebook, tagged NA", {
       1:4, haven::tagged_na("a", "c", "z")
     ),
     labels = c(
-      "Agreement" = 1, "Disagreement" = 4,
-      "First" = haven::tagged_na("c"), "Refused" = haven::tagged_na("a"),
-      "Not home" = haven::tagged_na("z")
+      Agreement = 1,
+      Disagreement = 4,
+      First = haven::tagged_na("c"),
+      Refused = haven::tagged_na("a"),
+      `Not home` = haven::tagged_na("z")
     )
   )
   expect_snapshot(data_codebook(data.frame(x)))
@@ -174,9 +176,11 @@ test_that("data_codebook, tagged NA", {
       1:4, haven::tagged_na("a", "c")
     ),
     labels = c(
-      "Agreement" = 1, "Disagreement" = 4,
-      "First" = haven::tagged_na("c"), "Refused" = haven::tagged_na("a"),
-      "Not home" = haven::tagged_na("z")
+      Agreement = 1,
+      Disagreement = 4,
+      First = haven::tagged_na("c"),
+      Refused = haven::tagged_na("a"),
+      `Not home` = haven::tagged_na("z")
     )
   )
   expect_snapshot(data_codebook(data.frame(x)))
@@ -187,11 +191,11 @@ test_that("data_codebook, negative label values #334", {
   skip_if_not_installed("haven")
   x1 <- haven::labelled(
     x = 1:4,
-    labels = c("Agreement" = 1, "Disagreement" = 4, "Missing" = -9)
+    labels = c(Agreement = 1, Disagreement = 4, Missing = -9)
   )
   x2 <- haven::labelled(
     x = c(1:3, -9),
-    labels = c("Agreement" = 1, "Disagreement" = 4, "Missing" = -9)
+    labels = c(Agreement = 1, Disagreement = 4, Missing = -9)
   )
   expect_snapshot(data_codebook(data.frame(x1, x2)))
 })
diff --git a/tests/testthat/test-data_merge.R b/tests/testthat/test-data_merge.R
index b98f4b8c8..ef48355bb 100644
--- a/tests/testthat/test-data_merge.R
+++ b/tests/testthat/test-data_merge.R
@@ -250,9 +250,9 @@ test_that("join data frames in a list", {
 
 # join empty data frames -----------------------
 
-x <- data.frame("x" = character(), stringsAsFactors = FALSE)
-y <- data.frame("x" = character(), stringsAsFactors = FALSE)
-z <- data.frame("y" = character(), stringsAsFactors = FALSE)
+x <- data.frame(x = character(), stringsAsFactors = FALSE)
+y <- data.frame(x = character(), stringsAsFactors = FALSE)
+z <- data.frame(y = character(), stringsAsFactors = FALSE)
 
 test_that("join empty data frames", {
   expect_identical(dim(data_merge(x, y, join = "left")), c(0L, 1L))
diff --git a/tests/testthat/test-data_rescale.R b/tests/testthat/test-data_rescale.R
index 2c24f0687..3539e2fc0 100644
--- a/tests/testthat/test-data_rescale.R
+++ b/tests/testthat/test-data_rescale.R
@@ -37,8 +37,8 @@ test_that("rescale works as expected", {
 
   expect_snapshot(
     head(rescale(iris, to = list(
-      "Sepal.Length" = c(0, 1),
-      "Petal.Length" = c(-1, 0)
+      Sepal.Length = c(0, 1),
+      Petal.Length = c(-1, 0)
     )))
   )
 })
diff --git a/tests/testthat/test-data_reverse.R b/tests/testthat/test-data_reverse.R
index b1fe1f73e..794591904 100644
--- a/tests/testthat/test-data_reverse.R
+++ b/tests/testthat/test-data_reverse.R
@@ -335,16 +335,20 @@ test_that("reverse_scale warns if single value to reverse", {
 test_that("reverse_scale select helpers", {
   data(iris)
   out <- rescale(iris, to = list(
-    "Sepal.Length" = c(0, 1),
-    "Petal.Length" = c(-1, 0)
+    Sepal.Length = c(0, 1),
+    Petal.Length = c(-1, 0)
   ), select = ends_with("length"))
 
   expect_identical(out$Sepal.Length, iris$Sepal.Length, tolerance = 1e-3)
 
-  out <- rescale(iris, to = list(
-    "Sepal.Length" = c(0, 1),
-    "Petal.Length" = c(-1, 0)
-  ), select = ends_with("length"), ignore_case = TRUE)
+  out <- rescale(iris,
+    to = list(
+      Sepal.Length = c(0, 1),
+      Petal.Length = c(-1, 0)
+    ),
+    select = ends_with("length"),
+    ignore_case = TRUE
+  )
 
   expect_identical(head(out$Sepal.Length), c(0.22222, 0.16667, 0.11111, 0.08333, 0.19444, 0.30556), tolerance = 1e-3)
 })
diff --git a/tests/testthat/test-data_to_factor.R b/tests/testthat/test-data_to_factor.R
index ee8a46c3e..0fd31b26a 100644
--- a/tests/testthat/test-data_to_factor.R
+++ b/tests/testthat/test-data_to_factor.R
@@ -22,7 +22,7 @@ test_that("to_factor", {
 # numeric, partially labelled
 test_that("to_factor", {
   x <- c(10, 11, 12)
-  attr(x, "labels") <- c("ten" = 10, "twelve" = 12)
+  attr(x, "labels") <- c(ten = 10, twelve = 12)
   expect_message(
     expect_identical(
       to_factor(x),