Change the default location of the personal library on Windows to be in

LOCALAPPDATA, instead of CSIDL_PERSONAL (PR#17842).


git-svn-id: https://svn.r-project.org/R/branches/R-ucrt@81354 00db46b3-68df-0310-9c12-caf00c1e9a41

doc/NEWS.Rd

@@ -196,7 +196,15 @@
       installation time.  See
       \url{https://developer.r-project.org/Blog/public/2021/12/07/upcoming-changes-in-r-4.2-on-windows}. 
       This measure is intended to end before R 4.2 is released.
-
+
+      \item The personal library on Windows, folder
+      \file{R\\win-library\\x.y} where \file{x.y} stands for \R release
+      \file{x.y.z}, is now by default a subdirectory of Local Application
+      Data (usually a hidden directory
+      \file{C:\\Users\\username\\AppData\\Local}).  Use
+      \code{shell.exec(.libPaths()[1])} to open the personal library in
+      explorer when it is first in the list (\PR{17842}).
+
       \item \R uses a new 64-bit Tcl/Tk bundle.  The previous 32-bit/64-bit
       combined bundle had a different layout and can no longer be used.
 
@@ -228,7 +236,7 @@
       is required from the user.
 
       \item The default installation directory of R for user-only installation
-      has been changed to the User Program Files (usually
+      has been changed to the User Program Files (usually a hidden directory
       \file{C:\\Users\\username\\AppData\\Local\\Programs}) to follow Windows
       conventions. Use \code{shell.exec(R.home())} to open \R installation
       directory in explorer (\PR{17842}).

doc/manual/rw-FAQ.texi

@@ -311,7 +311,9 @@ are quite deliberately installed in parallel folders so you can keep old
 versions around if you wish.
 
 For those with a personal library (folder @file{R\win-library\@var{x.y}}
-of your home directory, you will need to update that too when the minor version of R
+of your @file{$@{LOCALAPPDATA@}} directory in R since 4.2.0 or of your home
+directory with earlier versions of R),
+you will need to update that too when the minor version of R
 changes (e.g.@: from 4.0.2 to 4.1.0).  A simple way to do so is to
 copy (say) @file{R\win-library\4.0} to @file{R\win-library\4.1} before
 running @code{update.packages(checkBuilt=TRUE, ask=FALSE)}.
@@ -1110,8 +1112,10 @@ library(mypkg, lib.loc="p:/myRlib")
 @end example
 
 You can also have a personal library, which defaults to the directory
-@file{R\win-library\@var{x.y}} of your home directory for versions
-@var{x.y.z} of R.  This location can be changed by setting the
+@file{R\win-library\@var{x.y}} of your @file{$@{LOCALAPPDATA@}} directory
+(e.g. @file{C:\Users\username\AppData\Local}) for versions
+@var{x.y.z} since R 4.2.0. With older versions of R, it was a subdirectory
+of your home directory by default. This location can be changed by setting the
 environment variable @env{R_LIBS_USER}, and can be found from inside R
 by running @code{Sys.getenv("R_LIBS_USER")}.  This will only be used if
 it exists so you may need to create it: you can use

src/library/base/R/library.R

@@ -1,7 +1,7 @@
 #  File src/library/base/R/library.R
 #  Part of the R package, https://www.R-project.org
 #
-#  Copyright (C) 1995-2020 The R Core Team
+#  Copyright (C) 1995-2021 The R Core Team
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by
@@ -996,7 +996,7 @@ function(x)
         x.y <- paste0(R.version$major, ".",
                       sub("[.].*", "", R.version$minor))
         if(.Platform$OS.type == "windows")
-            file.path(home, "R", "win-library", x.y)
+            file.path(Sys.getenv("LOCALAPPDATA"), "R", "win-library", x.y)
         else if(s["sysname"] == "Darwin")
             file.path(home, "Library", "R", s["machine"], x.y, "library")
         else

src/library/base/man/libPaths.Rd

@@ -77,7 +77,9 @@
   on Unix-alike systems
   (or \file{Library/R/\var{m}/\var{x.y}/library} for CRAN macOS
   builds, with \var{m} \code{\link{Sys.info}()["machine"]})
-  and \file{R/win-library/\var{x.y}} on Windows, for \R \var{x.y.z}.
+  and \file{R/win-library/\var{x.y}} subdirectory of \env{LOCALAPPDATA} on Windows
+  (before \R 4.2.0, it was a subdirectory of the home directory even on
+  Windows), for \R \var{x.y.z}.
 
   Both \env{R_LIBS_USER} and \env{R_LIBS_SITE} feature possible
   expansion of specifiers for \R-version-specific information as part of
@@ -109,6 +111,10 @@
 
   For consistency, the paths are always normalized by
   \code{\link{normalizePath}(winslash = "/")}.
+
+  \env{LOCALAPPDATA} (usually \code{C:\\Users\\username\\AppData\\Local}) on
+  Windows is a hidden directory and may not be viewed by some software. It
+  may be opened by \code{shell.exec(Sys.getenv("LOCALAPPDATA"))}.
 }
 \value{
   A character vector of file paths.