Fix is_on_disk() for pkgload

Author: lionel-

DESCRIPTION

@@ -28,12 +28,14 @@ Suggests:
     cli (>= 3.1.0),
     covr,
     crayon,
+    desc,
     fs,
     glue,
     knitr,
     magrittr,
     methods,
     pillar,
+    pkgload,
     rmarkdown,
     stats,
     testthat (>= 3.2.0),

R/session.R

@@ -101,7 +101,23 @@ detect_installed <- function(info) {
 }
 
 is_on_disk <- function(pkg) {
-  any(file.exists(file.path(.libPaths(), pkg)))
+  system_file(pkg) != ""
+}
+
+system_file <- function(pkg) {
+  # Important for this to be first because packages loaded with pkgload
+  # will have a different path than the one in `.libPaths()` (if any).
+  if (isNamespaceLoaded(pkg)) {
+    return(.getNamespaceInfo(asNamespace(pkg), "path"))
+  }
+
+  for (path in file.path(.libPaths(), pkg)) {
+    if (file.exists(path)) {
+      return(path)
+    }
+  }
+
+  ""
 }
 
 pkg_version_info <- function(

tests/testthat/helper-package.R

@@ -0,0 +1,18 @@
+local_package <- function(
+  path = NULL,
+  name = "templatepackage",
+  env = caller_env()
+) {
+  if (is.null(path)) {
+    path <- withr::local_tempdir(.local_envir = env)
+    desc <- desc::desc("!new")
+    desc$set("Package", name)
+    desc$set("Title", "A test template package")
+    desc$write(file = file.path(path, "DESCRIPTION"))
+  }
+
+  pkgload::load_all(path, quiet = TRUE)
+  defer(pkgload::unload(name), envir = env)
+
+  path
+}

tests/testthat/test-session.R

@@ -272,3 +272,8 @@ test_that("check_installed() and is_installed() support character vectors", {
   expect_true(is_installed(chr()))
   expect_null(check_installed(chr()))
 })
+
+test_that("is_installed() works with pkgload-loaded packages", {
+  local_package(name = "rlangtestpkg")
+  expect_true(is_installed("rlangtestpkg"))
+})