Another attempt to fix low precision file systems

Author: s-fleck

CRAN-RELEASE

@@ -0,0 +1,2 @@
+This package was submitted to CRAN on 2020-10-27.
+Once it is accepted, delete this file and tag the release (commit 8fc994e32d).

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: rotor
 Title: Log Rotation and Conditional Backups
-Version: 0.3.3
+Version: 0.3.4
 Authors@R: 
     person(given = "Stefan",
            family = "Fleck",

NEWS.md

@@ -1,3 +1,7 @@
+# rotor 0.3.4
+
+* Further fixes for the issue mentioned in 0.3.3
+
 # rotor 0.3.3
 
 * Hotfix for some tests related to the `Cache` R6 class that fail on systems

R/Cache.R

@@ -162,8 +162,7 @@ Cache <- R6::R6Class(
 
       if (!is.null(max_size) && !is.infinite(max_size)){
         max_size  <- parse_size(max_size)
-        files <- files[order(files$mtime, decreasing = TRUE), ]
-        files$cumsize <- cumsum(files$size)
+        files$cumsize <- rev(cumsum(rev(files$size)))
         rem$size <- files[files$cumsize > max_size, ]
       }
 

cran-comments.md

@@ -10,9 +10,5 @@
 
 0 errors | 0 warnings | 0 notes
 
-Another - hopefully final attempt - to fix a hard to debug issue where some
-tests can fail on systems with low-precission filesystem-timestamps 
-(such as ext3 and old Windows filesystems).
-
-Added a test that mocks low-precision filesystem-timestamps to be on the safe
-side.
+More fixes for file-system timestamp related bugs that I could not reproduce on
+my test systems. Sorry again for all the trouble.

tests/testthat/test_BackupQueue.R

@@ -458,6 +458,7 @@ test_that("BackupQueueIndex$push() can push to different directory", {
 
 
 test_that("BackupQueueIndex dry run doesnt modify file system", {
+  try({unlink(td, recursive = TRUE)})
   dir.create(td, recursive = TRUE)
   on.exit(unlink(td, recursive = TRUE))
 

tests/testthat/test_Cache.R

@@ -126,26 +126,22 @@ test_that("$files is ordered by key if timestamps are identical", {
 
 
 
-test_that("pruning by size works", {
+test_that("pruning by size works, even if timestamps are identical", {
   td <- file.path(tempdir(), "cache-test")
   on.exit(unlink(td, recursive = TRUE))
 
   # When using a real hash function as hashfun, identical objects will only
   # be added to the cache once
   cache <- Cache$new(td, hashfun = function(x) ascending_id())
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
+  for (i in 1:5)  cache$push(iris)
   cache$push(cars)
   expect_identical(cache$n, 6L)
 
+
+  for (p in cache$files$path){  # loop necessary for compat with R < 3.6.0
+    Sys.setFileTime(p, "1999-01-01 00:00:00")
+  }
+
   expect_true(cache$size > 2048)
   cache$prune(max_size = "2kb")
   expect_true(cache$size <= 2048)
@@ -165,16 +161,7 @@ test_that("Inf max_* do not prunes", {
   # When using a real hash function as hashfun, identical objects will only
   # be added to the cache once
   cache <- Cache$new(td, hashfun = function(x) ascending_id())
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
+  for (i in 1:5)  cache$push(iris)
   cache$push(cars)
   expect_identical(cache$n, 6L)
 
@@ -232,16 +219,7 @@ test_that("pruning by age works", {
 
   cache <- MockCache$new(dir = td, hashfun = function(x) ascending_id())
   on.exit(cache$purge(), add = TRUE)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
-  cache$push(iris)
-  Sys.sleep(0.1)
+  for (i in 1:5)  cache$push(iris)
 
   expect_identical(nrow(cache$files), 5L)