Merge pull request #962 from r-lib/issue-961

Don't tolerate empty non-zero byte files

Author: lorenzwalthert

NEWS.md

@@ -30,22 +30,23 @@ editor_options:
     there is no literal code immediately following after the end of the example
     section (#940).
 
+-   Files with no tokens in it are now transformed into zero-byte files (#962).
+
 **Other**
 
--   Old (and outdated) vignettes have been removed (\@IndrajeetPatil, #955).
-    To access them, do `git checkout v1.0.0`.
+-   Old (and outdated) vignettes have been removed (\@IndrajeetPatil, #955). To
+    access them, do `git checkout v1.0.0`.
 -   Upgrade testing infra to testthat 3e (\@IndrajeetPatil, #949).
 -   Minor improvements to the documentation (\@IndrajeetPatil, #958).
 -   All (R)md files in this project's source code are now formatted with
     default pandoc markdown formatter. This conversion is required when using
     the visual mode in RStudio (#941).
 -   Update {pkgdown} action to always build, but only deploy on default branch
     (#946).
--   turned off `styler.print.Vertical` in vignettes so ANSI output of {prettycode} 
-    not messing with {pkgdown} (\@IndrajeetPatil, #956, #957). 
+-   turned off `styler.print.Vertical` in vignettes so ANSI output of
+    {prettycode} not messing with {pkgdown} (\@IndrajeetPatil, #956, #957).
 -   Improved code quality by fixing {lintr} warnings (#960).
 
-
 # styler 1.7.0
 
 -   if `else` follows directly after `if`, line breaks are removed (#935).

R/io.R

@@ -27,8 +27,11 @@ transform_utf8_one <- function(path, fun, dry) {
     {
       file_with_info <- read_utf8(path)
       # only write back when changed OR when there was a missing newline
-      new <- fun(file_with_info$text)
-      identical_content <- identical(unclass(file_with_info$text), unclass(new))
+      new <- unclass(fun(file_with_info$text))
+      if (identical(new, "")) {
+        new <- character(0)
+      }
+      identical_content <- identical(file_with_info$text, new)
       identical <- identical_content && !file_with_info$missing_EOF_line_break
       if (!identical) {
         if (dry == "fail") {

tests/testthat/test-exception_handling.R

@@ -18,7 +18,7 @@ test_that("style_text with no tokens returns empty string and warning", {
 
 test_that("style_file with no tokens returns empty string and warning", {
   capture_output(expect_warning(
-    style_file(testthat_file("exception_handling", "empty_file.R")),
+    style_file(testthat_file("exception_handling", "empty_file.R"), dry = "on"),
     "not contain any tokens."
   ))
 })

tests/testthat/test-encoding.R renamed to tests/testthat/test-io.R

@@ -1,5 +1,3 @@
-
-
 test_that("non-ASCII characters are handled properly for text styling", {
   expect_equal(
     style_text("glück <-3") %>% unclass(), "glück <- 3"
@@ -26,3 +24,13 @@ test_that("non-ASCII characters are handled properly for file styling", {
     }
   )
 })
+
+test_that("empty files are converted to zero-bite files", {
+  local_test_setup()
+  for (file_content in list(character(), "", c("", ""))) {
+    tmp <- tempfile(fileext = ".R")
+    write_utf8(file_content, tmp)
+    suppressWarnings(style_file(tmp))
+    expect_true(file.size(tmp) == 0)
+  }
+})