[WIP] new function 'addPackageGitHub()' (#50)

implemented a version of @msteijaert's function, though note the following TODOs need to make it fully functional:

* needs to handle `HEAD` instead of `master` (to allow for `main` branch)
* allow arbitrary git reference, à la `devtools::install_github()`
* allow installation from github repo that keeps pkg in a subdir
* use `GITHUB_PAT` to allow downloading from private repos
* `addLocalPackage()` does not add the dependencies of the locally built package!

NAMESPACE

@@ -40,3 +40,4 @@ importFrom(utils,download.packages)
 importFrom(utils,flush.console)
 importFrom(utils,installed.packages)
 importFrom(utils,select.list)
+importFrom(utils,unzip)

R/addPackages.R

@@ -372,3 +372,40 @@ addLocalPackage <- function(pkgs = NULL, pkgPath = NULL, path = NULL,
   }
   invisible(ret)
 }
+
+#' Add package from GitHub
+#'
+#' @param repo Github repository name in the format `username/repo`.
+#' @param ... Additional arguments passed to `addLocalPackage()`.
+#'
+#' @export.
+#' @docType methods
+#'
+#' @author Marvin Steijaert
+#' @author Alex Chubaty
+#' 
+#' @note Currently, only installing from master branch is supported.
+#' 
+#' @importFrom utils unzip
+#' 
+#' @examples
+#' \dontrun{
+#'   addPackageGitHub("andrie/miniCRAN", path = reposPath)
+#' }
+addPackageGitHub <- function(repo, ...) {
+  packageName <- basename(repo)
+  exDir <- file.path(tempdir(), packageName)
+  if (dir.exists(exDir)) unlink(exDir, recursive = TRUE)
+  zipFile <- file.path(tempdir(), paste0(packageName, ".zip"))
+
+  ## TODO: needs to handle HEAD instead of 'master' (to allow for 'main' branch)
+  ## TODO: allow arbitrary git reference, à la devtools::install_github()
+  ## TODO: allow installation from github repo that keeps pkg in a subdir
+  ## TODO: use GITHUB_PAT to allow downloading from private repos
+  download.file(paste0("https://github.com/", repo, "/zipball/master"), zipFile, mode = "wb")
+  unzip(zipFile, exdir = exDir)
+  file.rename(list.files(exDir, full.names = TRUE)[1], file.path(exDir, packageName))
+
+  ## TODO: addLocalPackage() does not add the dependencies of the locally built package!
+  addLocalPackage(packageName, exDir, ..., build = TRUE)
+}

tests/testthat/test-7-addGithubPackage.R

@@ -1,5 +1,5 @@
 
-test_that("can add package from github",{
+test_that("can add package listing from github",{
 
   skip_on_cran()
 
@@ -15,3 +15,24 @@ test_that("can add package from github",{
   expect_equal(nrow(pdb), nrow(newpdb))
   expect_equal(ncol(pdb), ncol(newpdb))
 })
+
+repo_path <- file.path(tempdir(), "cran")
+
+test_that("can add github package", {
+
+  skip_on_cran()
+
+  # Create a miniCRAN repo
+  unlink(repo_path, recursive = TRUE)
+  dir.create(repo_path, showWarnings = FALSE)
+  repo <- "https://cran.r-project.org"
+  miniCRAN::makeRepo(pkgs = c(), path = repo_path, type = "win.binary", repos = repo)
+
+  addPackageGitHub("andrie/miniCRAN", path = repo_path)
+
+  expect_message(
+    addPackageGitHub("andrie/miniCRAN", path = repo_path),
+    "All packages up to date. Nothing to add."
+  )
+
+})