simplify buildMask()

NAMESPACE

@@ -354,3 +354,4 @@ importFrom(htmltools,validateCssUnit)
 importFrom(htmltools,withTags)
 importFrom(promises,"%...!%")
 importFrom(promises,"%...>%")
+importFrom(rlang,env_clone)

R/test-server.R

@@ -1,13 +1,31 @@
-# Create a "data mask" suitable for passing to rlang::eval_tidy. Bindings in
-# `env` and bindings in the parent of `env` are merged into a single named list.
-# Bindings in `env` take precedence over bindings in the parent of `env`.
-#' @noRd
-makeMask <- function(env) {
-  stopifnot(length(rlang::env_parents(env)) > 1)
-  child <- as.list(env)
-  parent <- as.list(rlang::env_parent(env))
-  parent_only <- setdiff(names(parent), names(child))
-  append(child, parent[parent_only])
+# Constructs an rlang::eval_tidy() data mask with semantics appropriate for use
+# in testServer().
+#
+# env is assumed to be session$env, or the environment captured by invoking a
+# module under test.
+#
+# Consider the following module definition and its enclosing environment:
+#
+# x <- 1
+# m <- function(id) {
+#   y <- 2
+#   moduleServer(id, function(input, output, session){
+#     z <- 3
+#   })
+# }
+#
+# The data mask returned by this function should include z, session,
+# output, input, y, and id, but *not* x. Definitions not masked are
+# resolved in the environment in which testServer() is called.
+#
+# env is cloned because rlang::new_data_mask() mutates the parent of its `top`
+# argument.
+#' @importFrom rlang env_clone
+buildMask <- function(env) {
+  if (identical(parent.env(env), emptyenv()))
+    stop("env must have a non-empty parent")
+  clone <- env_clone(env, env_clone(parent.env(env), emptyenv()))
+  rlang::new_data_mask(clone, parent.env(clone))
 }
 
 #' @noRd
@@ -112,7 +130,7 @@ testServer <- function(app, expr, ...) {
     withReactiveDomain(
       session,
       withr::with_options(list(`shiny.allowoutputreads` = TRUE), {
-        rlang::eval_tidy(quosure, makeMask(session$env), rlang::caller_env())
+        rlang::eval_tidy(quosure, buildMask(session$env), rlang::caller_env())
       })
     )
   )

man/markdown.Rd

@@ -4,29 +4,34 @@
 \alias{markdown}
 \title{Insert inline Markdown}
 \usage{
-markdown(mds, extensions = TRUE, ...)
+markdown(mds, extensions = TRUE, .noWS = NULL, ...)
 }
 \arguments{
 \item{mds}{A character vector of Markdown source to convert to HTML. If the
-vector has more than one element, resulting HTML is concatenated.}
+vector has more than one element, a single-element character vector of
+concatenated HTML is returned.}
 
-\item{extensions}{Enable Github syntax extensions, defaults to \code{TRUE}.}
+\item{extensions}{Enable Github syntax extensions; defaults to \code{TRUE}.}
+
+\item{.noWS}{Character vector used to omit some of the whitespace that would
+normally be written around generated HTML. Valid options include \code{before},
+\code{after}, and \code{outside} (equivalent to \code{before} and \code{end}).}
 
 \item{...}{Additional arguments to pass to \code{\link[commonmark:markdown_html]{commonmark::markdown_html()}}.
 These arguments are \emph{\link[rlang:dyn-dots]{dynamic}}.}
 }
 \value{
-an \code{html}-classed character vector of rendered HTML
+a character vector marked as HTML.
 }
 \description{
-This function accepts a character vector of
-\href{https://en.wikipedia.org/wiki/Markdown}{Markdown}-syntax text and renders
-it to HTML that may be included in a UI.
+This function accepts
+\href{https://en.wikipedia.org/wiki/Markdown}{Markdown}-syntax text and returns
+HTML that may be included in Shiny UIs.
 }
 \details{
-Prior to interpretation as Markdown, leading whitespace is trimmed from text
-with \code{\link[glue:trim]{glue::trim()}}. This makes it possible to insert Markdown and for it to
-be processed correctly even when the call to \code{markdown()} is indented.
+Leading whitespace is trimmed from Markdown text with \code{\link[glue:trim]{glue::trim()}}.
+Whitespace trimming ensures Markdown is processed correctly even when the
+call to \code{markdown()} is indented within surrounding R code.
 
 By default, \link[commonmark:extensions]{Github extensions} are enabled, but this
 can be disabled by passing \code{extensions = FALSE}.