Make data/ directory automatically accessible to exercises

NEWS.md

@@ -20,6 +20,7 @@ learnr (development version)
 * Previously, when a question submission was reset, it would be recorded as a `"question_submission"` event with the value `reset=TRUE`. Now it a separate event, `"reset_question_submission"`. ([#398](https://github.com/rstudio/learnr/pull/398))
 * Added a new `polyglot` tutorial to learnr. This tutorial displays mixing R, python, and sql exercises. See [`run_tutorial("polyglot", "learnr")`](https://learnr-examples.shinyapps.io/polyglot) for a an example. ([#397](https://github.com/rstudio/learnr/pull/397))
 * Text throughout the learnr interface can be customized or localized using the new `language` argument of `tutorial()`. Translations for English and French are provided and contributes will be welcomed. Read more about these features in `vignette("multilang", package = "learnr")`. ([#456](https://github.com/rstudio/learnr/pull/456), [#479](https://github.com/rstudio/learnr/pull/479))
+* When a "data/" directory is found in the same directory as the tutorial R Markdown document, it is now automatically made available within exercises. An alternative directory can be specified using the `tutorial.data_dir` global option. ([#539](https://github.com/rstudio/learnr/pull/539))
 
 ## Minor new features and improvements
 

R/data_dir.R

@@ -0,0 +1,34 @@
+copy_data_dir <- function(source_dir, exercise_dir) {
+  if (is.null(source_dir)) {
+    # First check options(), then environment variable, then default to "data/"
+    source_dir <- getOption(
+      "tutorial.data_dir",
+      Sys.getenv("TUTORIAL_DATA_DIR", if (dir.exists("data")) "data" else "")
+    )
+  }
+
+  if (identical(source_dir, "")) {
+    return(invisible(NULL))
+  }
+
+  if (!dir.exists(source_dir)) {
+    rlang::abort(
+      "An error occurred with the tutorial: the data directory does not exist.",
+      class = "learnr_missing_source_data_dir"
+    )
+  }
+
+  dest_dir <- file.path(exercise_dir, "data")
+  dir.create(dest_dir)
+
+  if (!dir.exists(dest_dir)) {
+    rlang::abort(
+      "An error occurred with the tutorial: we weren't able to create the data directory for this exercise.",
+      class = "learnr_missing_dest_data_dir"
+    )
+  }
+
+  file.copy(dir(source_dir, full.names = TRUE), dest_dir, recursive = TRUE)
+
+  return(invisible(dest_dir))
+}

R/exercise.R

@@ -283,10 +283,11 @@ required_names <- c("code", "label", "options", "chunks", require_items)
 #   been executed, so they'd typically use `FALSE`, the default. Remote
 #   evaluators, if they choose to use this function, might want to include the
 #   global setup.
-evaluate_exercise <- function(exercise, envir, evaluate_global_setup = FALSE) {
+evaluate_exercise <- function(
+  exercise, envir, evaluate_global_setup = FALSE, data_dir = NULL
+) {
   # Protect global options and environment vars from permanent modification
-  withr::local_options(list())
-  withr::local_envvar(as.list(Sys.getenv()))
+  local_restore_options_and_envvars()
 
   # adjust exercise version to match the current learnr version
   exercise <- upgrade_exercise(
@@ -312,6 +313,9 @@ evaluate_exercise <- function(exercise, envir, evaluate_global_setup = FALSE) {
   dir.create(exercise_dir)
   on.exit(unlink(exercise_dir), add = TRUE)
 
+  # Copy files from data directory into exercise
+  copy_data_dir(data_dir, exercise_dir)
+
   checker_feedback <- NULL
   # Run the checker pre-evaluation _if_ there is code checking to do
   if (length(exercise$code_check)) {
@@ -434,8 +438,7 @@ get_checker_func <- function(exercise, name, envir) {
 
 render_exercise <- function(exercise, envir) {
   # Protect global options and environment vars from modification by student
-  withr::local_options(list())
-  withr::local_envvar(as.list(Sys.getenv()))
+  local_restore_options_and_envvars()
 
   # Make sure exercise (& setup) chunk options and code are prepped for rendering
   exercise <- prepare_exercise(exercise)
@@ -789,6 +792,34 @@ merge_options <- function(preserved_opts, inherited_opts, static_opts = list())
   opts[!grepl("^exercise", names(opts))]
 }
 
+local_restore_options_and_envvars <- function(.local_envir = parent.frame()) {
+  local_restore_options(.local_envir)
+  local_restore_envvars(.local_envir)
+}
+
+local_restore_options <- function(.local_envir = parent.frame()) {
+  opts <- options()
+  withr::defer(restore_options(opts), envir = .local_envir)
+}
+
+local_restore_envvars <- function(.local_envir = parent.frame()) {
+  envvars <- Sys.getenv()
+  withr::defer(restore_envvars(envvars), envir = .local_envir)
+}
+
+restore_options <- function(old) {
+  current    <- options()
+  nulls      <- setdiff(names(current), names(old))
+  old[nulls] <- list(NULL)
+  options(old)
+}
+
+restore_envvars <- function(old) {
+  current <- Sys.getenv()
+  nulls   <- setdiff(names(current), names(old))
+  Sys.unsetenv(nulls)
+  do.call(Sys.setenv, as.list(old))
+}
 
 #' An Exercise Checker for Debugging
 #'

docs/_site.yml

@@ -5,9 +5,9 @@ output:
     theme: cosmo
     highlight: textmate
     toc: true
-    toc_depth: 2
+    toc_depth: 3
     toc_float: 
-      collapsed: false
+      collapsed: true
     css: styles.css
     includes:
       in_header: _include/header.html

docs/examples.html

@@ -13,12 +13,22 @@
 
 <title>Examples</title>
 
+<script src="site_libs/header-attrs-2.9/header-attrs.js"></script>
 <script src="site_libs/jquery-1.11.3/jquery.min.js"></script>
 <meta name="viewport" content="width=device-width, initial-scale=1" />
 <link href="site_libs/bootstrap-3.3.5/css/cosmo.min.css" rel="stylesheet" />
 <script src="site_libs/bootstrap-3.3.5/js/bootstrap.min.js"></script>
 <script src="site_libs/bootstrap-3.3.5/shim/html5shiv.min.js"></script>
 <script src="site_libs/bootstrap-3.3.5/shim/respond.min.js"></script>
+<style>h1 {font-size: 34px;}
+       h1.title {font-size: 38px;}
+       h2 {font-size: 30px;}
+       h3 {font-size: 24px;}
+       h4 {font-size: 18px;}
+       h5 {font-size: 16px;}
+       h6 {font-size: 12px;}
+       code {color: inherit; background-color: rgba(0, 0, 0, 0.04);}
+       pre:not([class]) { background-color: white }</style>
 <script src="site_libs/navigation-1.1/tabsets.js"></script>
 <link href="site_libs/highlightjs-9.12.0/textmate.css" rel="stylesheet" />
 <script src="site_libs/highlightjs-9.12.0/highlight.js"></script>
@@ -47,11 +57,6 @@
     </style>
 
 <style type="text/css">code{white-space: pre;}</style>
-<style type="text/css">
-  pre:not([class]) {
-    background-color: white;
-  }
-</style>
 <script type="text/javascript">
 if (window.hljs) {
   hljs.configure({languages: []});
@@ -64,32 +69,6 @@
 
 
 
-<style type="text/css">
-h1 {
-  font-size: 34px;
-}
-h1.title {
-  font-size: 38px;
-}
-h2 {
-  font-size: 30px;
-}
-h3 {
-  font-size: 24px;
-}
-h4 {
-  font-size: 18px;
-}
-h5 {
-  font-size: 16px;
-}
-h6 {
-  font-size: 12px;
-}
-.table th:not([align]) {
-  text-align: left;
-}
-</style>
 
 
 <link rel="stylesheet" href="styles.css" type="text/css" />
@@ -102,10 +81,6 @@
   margin-left: auto;
   margin-right: auto;
 }
-code {
-  color: inherit;
-  background-color: rgba(0, 0, 0, 0.04);
-}
 img {
   max-width:100%;
 }
@@ -121,40 +96,13 @@
 summary {
   display: list-item;
 }
+pre code {
+  padding: 0;
+}
 </style>
 
 
 <style type="text/css">
-/* padding for bootstrap navbar */
-body {
-  padding-top: 51px;
-  padding-bottom: 40px;
-}
-/* offset scroll position for anchor links (for fixed navbar)  */
-.section h1 {
-  padding-top: 56px;
-  margin-top: -56px;
-}
-.section h2 {
-  padding-top: 56px;
-  margin-top: -56px;
-}
-.section h3 {
-  padding-top: 56px;
-  margin-top: -56px;
-}
-.section h4 {
-  padding-top: 56px;
-  margin-top: -56px;
-}
-.section h5 {
-  padding-top: 56px;
-  margin-top: -56px;
-}
-.section h6 {
-  padding-top: 56px;
-  margin-top: -56px;
-}
 .dropdown-submenu {
   position: relative;
 }
@@ -182,7 +130,7 @@
   margin-right: -10px;
 }
 .dropdown-submenu:hover>a:after {
-  border-left-color: #ffffff;
+  border-left-color: #adb5bd;
 }
 .dropdown-submenu.pull-left {
   float: none;
@@ -194,7 +142,7 @@
 }
 </style>
 
-<script>
+<script type="text/javascript">
 // manage active state of menu based on current page
 $(document).ready(function () {
   // active menu anchor
@@ -205,10 +153,23 @@
   var menuAnchor = $('a[href="' + href + '"]');
 
   // mark it active
-  menuAnchor.parent().addClass('active');
+  menuAnchor.tab('show');
 
   // if it's got a parent navbar menu mark it active as well
   menuAnchor.closest('li.dropdown').addClass('active');
+
+  // Navbar adjustments
+  var navHeight = $(".navbar").first().height() + 15;
+  var style = document.createElement('style');
+  var pt = "padding-top: " + navHeight + "px; ";
+  var mt = "margin-top: -" + navHeight + "px; ";
+  var css = "";
+  // offset scroll position for anchor links (for fixed navbar)
+  for (var i = 1; i <= 6; i++) {
+    css += ".section h" + i + "{ " + pt + mt + "}\n";
+  }
+  style.innerHTML = "body {" + pt + "padding-bottom: 40px; }\n" + css;
+  document.head.appendChild(style);
 });
 </script>
 
@@ -220,7 +181,6 @@
   max-height: 500px;
   min-height: 44px;
   overflow-y: auto;
-  background: white;
   border: 1px solid #ddd;
   border-radius: 4px;
 }
@@ -318,7 +278,7 @@
       <ul class="nav navbar-nav navbar-right">
         <li>
   <a href="https://github.com/rstudio/learnr">
-    <span class="fas fa-github"></span>
+    <span class="fa fa-github"></span>
 
   </a>
 </li>
@@ -327,7 +287,7 @@
   </div><!--/.container -->
 </div><!--/.navbar -->
 
-<div class="fluid-row" id="header">
+<div id="header">
 
 
 
@@ -460,7 +420,7 @@ <h1 class="title toc-ignore">Examples</h1>
 
 $(document).ready(function () {
   $('.tabset-dropdown > .nav-tabs > li').click(function () {
-    $(this).parent().toggleClass('nav-tabs-open')
+    $(this).parent().toggleClass('nav-tabs-open');
   });
 });
 </script>