Add support for devtools loaded package in draft() (#2224)

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: rmarkdown
 Type: Package
 Title: Dynamic Documents for R
-Version: 2.11.1
+Version: 2.11.2
 Authors@R: c(
   person("JJ", "Allaire", role = "aut", email = "jj@rstudio.com"),
   person("Yihui", "Xie", role = c("aut", "cre"), email = "xie@yihui.name", comment = c(ORCID = "0000-0003-0645-5666")),

NEWS.md

@@ -1,6 +1,7 @@
 rmarkdown 2.12
 ================================================================================
 
+- `draft()` now works with `devtools::load_all()` and **testthat** when used in other packages. 
 
 rmarkdown 2.11
 ================================================================================

R/draft.R

@@ -63,7 +63,7 @@ draft <- function(file,
 
   # resolve package file
   if (!is.null(package)) {
-    template_path = system.file("rmarkdown", "templates", template,
+    template_path = pkg_file("rmarkdown", "templates", template,
                                 package = package)
     if (!nzchar(template_path)) {
       stop("The template '", template, "' was not found in the ",

R/util.R

@@ -47,11 +47,11 @@ pandoc_output_ext <- function(ext, to, input) {
 # From pkgdown:
 # https://github.com/r-lib/pkgdown/blob/04d3a76892320ac4bd918b39604c157e9f83507a/R/utils-fs.R#L85
 pkg_file <- function(..., package = "rmarkdown", mustWork = FALSE) {
-  if (is.null(devtools_meta(package))) {
-    system.file(..., package = package, mustWork = mustWork)
-  } else {
+  if (devtools_loaded(package)) {
     # used only if package has been loaded with devtools or pkgload
-    file.path(getNamespaceInfo(package, "path"), "inst", ...)
+    file.path(find.package(package), "inst", ...)
+  } else {
+    system.file(..., package = package, mustWork = mustWork)
   }
 }
 
@@ -566,10 +566,13 @@ stop2 = function(...) stop(..., call. = FALSE)
 
 # devtools metadata -------------------------------------------------------
 
-# from pkgdown
+# from pkgdown & downlit
 # https://github.com/r-lib/pkgdown/blob/77f909b0138a1d7191ad9bb3cf95e78d8e8d93b9/R/utils.r#L52
 
-devtools_meta <- function(package) {
-  ns <- .getNamespace(package)
-  ns[[".__DEVTOOLS__"]]
+devtools_loaded <- function(x) {
+  if (!x %in% loadedNamespaces()) {
+    return(FALSE)
+  }
+  ns <- .getNamespace(x)
+  !is.null(ns$.__DEVTOOLS__)
 }