Strip .data from default labels

NEWS.md

@@ -162,6 +162,9 @@ fail.
 * `stat_summary()` and related functions now support rlang-style lambda functions
   (#3568, @dkahle).
 
+* `strip_dots()` strips the data masking pronoun `.data` to make better
+  axis labels.
+
 * Addition of partial themes to plots has been made more predictable;
   stepwise addition of individual partial themes is now equivalent to
   addition of multple theme elements at once (@clauswilke, #3039).

R/aes-evaluation.r

@@ -132,7 +132,7 @@ is_staged <- function(x) {
 }
 
 # Strip dots from expressions
-strip_dots <- function(expr) {
+strip_dots <- function(expr, env) {
   if (is.atomic(expr)) {
     expr
   } else if (is.name(expr)) {
@@ -144,23 +144,30 @@ strip_dots <- function(expr) {
     }
   } else if (is_quosure(expr)) {
     # strip dots from quosure and reconstruct the quosure
-    expr <- new_quosure(
-      strip_dots(quo_get_expr(expr)),
+    new_quosure(
+      strip_dots(quo_get_expr(expr), env = quo_get_env(expr)),
       quo_get_env(expr)
     )
   } else if (is.call(expr)) {
-    if (identical(expr[[1]], quote(stat))) {
+    if (is_call(expr, "$") && is_symbol(expr[[2]], ".data")) {
+      expr[[3]]
+    } else if (is_call(expr, "[[") && is_symbol(expr[[2]], ".data")) {
+      tryCatch(
+        sym(eval(expr[[3]], env)),
+        error = function(e) expr[[3]]
+      )
+    } else if (is_call(expr, "stat")) {
       strip_dots(expr[[2]])
     } else {
-      expr[-1] <- lapply(expr[-1], strip_dots)
+      expr[-1] <- lapply(expr[-1], strip_dots, env = env)
       expr
     }
   } else if (is.pairlist(expr)) {
     # In the unlikely event of an anonymous function
-    as.pairlist(lapply(expr, strip_dots))
+    as.pairlist(lapply(expr, strip_dots, env = env))
   } else if (is.list(expr)) {
     # For list of aesthetics
-    lapply(expr, strip_dots)
+    lapply(expr, strip_dots, env = env)
   } else {
     abort(glue("Unknown input: {class(expr)[1]}"))
   }

tests/testthat/test-aes-calculated.r

@@ -24,6 +24,18 @@ test_that("strip_dots remove dots around calculated aesthetics", {
   )
 })
 
+test_that("strip_dots handles tidy evaluation pronouns", {
+  expect_identical(strip_dots(aes(.data$x))$x, quo(x))
+  expect_identical(strip_dots(aes(.data[["x"]]))$x, quo(x))
+
+  var <- "y"
+  f <- function() {
+    var <- "x"
+    aes(.data[[var]])$x
+  }
+  expect_identical(quo_get_expr(strip_dots(f())), quote(x))
+})
+
 test_that("make_labels() deprases mappings properly", {
   # calculation stripped from labels
   expect_identical(make_labels(aes(x = ..y..)), list(x = "y"))