improve handling of Windows paths (#2069)

NEWS.md

@@ -1,6 +1,9 @@
 
 # renv 1.1.0  (UNRELEASED)
 
+* Fixed an issue where `RENV_CONFIG_EXTERNAL_LIBRARIES` was incorrectly
+  split when using Windows paths. (#2069)
+
 * Fixed an issue where `renv` failed to restore packages installed from
   r-universe when the associated lockfile record had no `RemoteRef` field.
   (#2068)

R/config.R

@@ -138,7 +138,28 @@ renv_config_decode_envvar <- function(envname, envval) {
   else
     "\\s*,\\s*"
 
-  strsplit(envval, pattern, perl = TRUE)[[1L]]
+  values <- strsplit(envval, pattern, perl = TRUE)[[1L]]
+
+  # fix up single-letter paths for Windows
+  # https://github.com/rstudio/renv/issues/2069
+  result <- stack(mode = "character")
+
+  i <- 1L
+  while (i <= length(values)) {
+
+    if (nchar(values[[i]]) == 1L) {
+      value <- paste(values[[i]], values[[i + 1L]], sep = ":")
+      result$push(value)
+      i <- i + 2L
+    } else {
+      value <- values[[i]]
+      result$push(value)
+      i <- i + 1L
+    }
+
+  }
+
+  result$data()
 
 }
 

tests/testthat/test-config.R

@@ -80,9 +80,9 @@ test_that("we can query the default configuration values without issue", {
 
 test_that("multiple library paths can be set in RENV_CONFIG_EXTERNAL_LIBRARIES", {
 
-  renv_scope_envvars(RENV_CONFIG_EXTERNAL_LIBRARIES = "a:b:c")
+  renv_scope_envvars(RENV_CONFIG_EXTERNAL_LIBRARIES = "/a:/b:/c")
   libpaths <- config$external.libraries()
-  expect_equal(libpaths, c("a", "b", "c"))
+  expect_equal(libpaths, c("/a", "/b", "/c"))
 
 })
 
@@ -102,3 +102,49 @@ test_that("cache symlinks are disabled if the cache and project library lie in d
 
 
 })
+
+test_that("RENV_CONFIG_EXTERNAL_LIBRARIES is decoded appropriately", {
+
+  envname <- "RENV_CONFIG_EXTERNAL_LIBRARIES"
+
+  expect_equal(
+    renv_config_decode_envvar(envname, "/apple"),
+    "/apple"
+  )
+
+  expect_equal(
+    renv_config_decode_envvar(envname, "C:/apple"),
+    "C:/apple"
+  )
+
+  expect_equal(
+    renv_config_decode_envvar(envname, "C:/apple:C:/banana"),
+    c("C:/apple", "C:/banana")
+  )
+
+  expect_equal(
+    renv_config_decode_envvar(envname, "C:/apple;C:/banana"),
+    c("C:/apple", "C:/banana")
+  )
+
+  expect_equal(
+    renv_config_decode_envvar(envname, "C:/apple,C:/banana"),
+    c("C:/apple", "C:/banana")
+  )
+
+  expect_equal(
+    renv_config_decode_envvar(envname, "/apple:/banana"),
+    c("/apple", "/banana")
+  )
+
+  expect_equal(
+    renv_config_decode_envvar(envname, "/apple;/banana"),
+    c("/apple", "/banana")
+  )
+
+  expect_equal(
+    renv_config_decode_envvar(envname, "/apple,/banana"),
+    c("/apple", "/banana")
+  )
+
+})

tests/testthat/test-envvar.R

@@ -1,3 +1,4 @@
+
 test_that("can add before or after", {
   path_string <- function(...) {
     paste(c(...), collapse = .Platform$path.sep)