From cd968ba4950bbb1a9f5075fd8f5666720b04103f Mon Sep 17 00:00:00 2001
From: Yihui Xie <xie@yihui.name>
Date: Mon, 21 Sep 2020 23:41:37 -0500
Subject: [PATCH] install the package in a temp directory and load it before
 running tests; the temp directory will be deleted after the R session ends

this will no longer be necessary: https://github.com/yihui/xfun/issues/5#issuecomment-688593940
---
 DESCRIPTION |  2 +-
 NEWS        |  3 +++
 R/testit.R  | 23 +++++++++++++++++++++++
 R/utils.R   |  6 ++++++
 R/zzz.R     |  7 +++++++
 5 files changed, 40 insertions(+), 1 deletion(-)
 create mode 100644 R/zzz.R

diff --git a/DESCRIPTION b/DESCRIPTION
index 668f7ae..9876ba1 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: testit
 Type: Package
 Title: A Simple Package for Testing R Packages
-Version: 0.11.1
+Version: 0.11.2
 Authors@R: c(
   person("Yihui", "Xie", role = c("aut", "cre"), email = "xie@yihui.name", comment = c(ORCID = "0000-0003-0645-5666")), 
   person("Steven", "Mortimer", role = "ctb", email="reportmort@gmail.com")
diff --git a/NEWS b/NEWS
index dfbf814..a2e71e3 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,8 @@
     CHANGES IN testit VERSION 0.12
 
+MAJOR CHANGES
+
+  o `test_pkg()` installs the package before running tests when it is called from a non-interactive R session that is not launched by `R CMD check`, e.g., when you run tests in RStudio via `Ctrl/Cmd + Shift + T`, so you will not have to install the package manually (`Ctrl/Cmd + Shift + B`) before running tests.
 
     CHANGES IN testit VERSION 0.11
 
diff --git a/R/testit.R b/R/testit.R
index 75c898c..f5971d5 100644
--- a/R/testit.R
+++ b/R/testit.R
@@ -164,6 +164,29 @@ assert2 = function(fact, exprs, envir, all = TRUE) {
 #' @export
 #' @examples \dontrun{test_pkg('testit')}
 test_pkg = function(package, dir = c('testit', 'tests/testit')) {
+  # install the source package before running tests when this function is called
+  # in a non-interactive R session that is not `R CMD check`
+  install = !.env$installed && !interactive() &&
+    file.exists(desc <- file.path('../DESCRIPTION')) &&
+    is.na(Sys.getenv('_R_CHECK_PACKAGE_NAME_', NA)) &&
+    !is.na(p <- read.dcf(desc, fields = 'Package')[1, 1]) && p == package
+  if (install) {
+    .env$lib_old = lib_old = .libPaths()
+    .env$lib_new = lib_new = tempfile('R-lib-', '.'); dir.create(lib_new)
+    res = system2(
+      file.path(R.home('bin'), 'R'), c(
+        'CMD', 'INSTALL', paste0('--library=', lib_new),
+        '--no-help', '--no-staged-install', '--no-test-load', '..'
+      )
+    )
+    if (res == 0) {
+      .libPaths(c(lib_new, lib_old))
+      .env$installed = TRUE
+    }
+  }
+  if (!is.na(i <- match(paste0('package:', package), search())))
+    detach(pos = i, unload = TRUE, force = TRUE)
+
   library(package, character.only = TRUE)
   path = available_dir(c(dir, system.file('tests', 'testit', package = package)))
   rs = list.files(path, '^test-.+[.][rR]$', full.names = TRUE)
diff --git a/R/utils.R b/R/utils.R
index ea488c4..4e626f4 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -1,3 +1,9 @@
+# an internal environment to store objects
+.env = new.env(parent = emptyenv())
+
+# has the package been installed once in test_pkg()?
+.env$installed = FALSE
+
 # find an available dir
 available_dir = function(dirs) {
   for (i in dirs) {
diff --git a/R/zzz.R b/R/zzz.R
new file mode 100644
index 0000000..9be334e
--- /dev/null
+++ b/R/zzz.R
@@ -0,0 +1,7 @@
+# clean up the temp library created in test_pkg() at the end of the R session
+.onLoad = function(libname, pkgname) {
+  reg.finalizer(.env, function(e) {
+    unlink(e$lib_new, recursive = TRUE)
+    if (!is.null(e$lib_old)) .libPaths(e$lib_old)
+  }, onexit = TRUE)
+}