Accept plugins argument for doctest

Forward keyword arguments from `doctest` to `makedocs`. This
includes the `plugins` keyword argument, but potentially other keyword
arguments as well.

CHANGELOG.md

@@ -132,6 +132,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 * The search UI has had a complete overhaul, with a fresh new modal UI with better context for search results and a filter mechanism to remove unwanted results. The client-side search engine has been changed from LunrJs to MinisearchJs. ([#1437], [#2141], [#2147], [#2202])
 
+* The `doctest` routine can now receive the same `plugins` keyword argument as `makedocs`. This enables `doctest` to run if any plugin with a mandatory `Plugin` object is loaded, e.g., [DocumenterCitations](https://github.com/JuliaDocs/DocumenterCitations.jl). ([#2245])
+
 ### Fixed
 
 * Line endings in Markdown source files are now normalized to `LF` before parsing, to work around [a bug in the Julia Markdown parser][julia-29344] where parsing is sensitive to line endings, and can therefore cause platform-dependent behavior. ([#1906])

src/doctest.jl

@@ -46,13 +46,16 @@ manual pages can be disabled if `source` is set to `nothing`.
 
 # Keywords
 
-**`testset`** specifies the name of test testset (default `Doctests`).
+**`testset`** specifies the name of test testset (default `"Doctests"`).
 
 **`doctestfilters`** vector of regex to filter tests (see the manual on [Filtering Doctests](@ref))
 
 **`fix`**, if set to `true`, updates all the doctests that fail with the correct output
 (default `false`).
 
+**`plugins`** is a list of [`Documenter.Plugin`](@ref) objects to be forwarded to
+[`makedocs`](@ref). Use as directed by the documentation of a third-party plugin.
+
 !!! warning
     When running `doctest(...; fix=true)`, Documenter will modify the Markdown and Julia
     source files. It is strongly recommended that you only run it on packages in Pkg's
@@ -66,6 +69,7 @@ function doctest(
         fix = false,
         testset = "Doctests",
         doctestfilters = Regex[],
+        plugins = Plugin[],
     )
     function all_doctests()
         dir = mktempdir()
@@ -75,7 +79,7 @@ function doctest(
                 source = joinpath(dir, "src")
                 mkdir(source)
             end
-            makedocs(
+            makedocs(;
                 root = dir,
                 source = source,
                 sitename = "",
@@ -85,6 +89,7 @@ function doctest(
                 # When doctesting, we don't really want to get bogged down with issues
                 # related to determining the remote repositories for edit URLs and such
                 remotes = nothing,
+                plugins = plugins,
             )
             true
         catch err

test/plugins/make.jl

@@ -84,7 +84,7 @@ A = _TestPluginA(false)
     plugins=[_RunPluginTests(true), A],
     sitename="-", modules = [PluginsTestModule], warnonly=false
 ) === nothing
-@test A.processed = true
+@test A.processed
 
 
 # Errors
@@ -116,4 +116,15 @@ catch exc
 end
 
 
+# Doctests  - the `doctest` function must also be able to process plugins
+
+A = _TestPluginA(false)
+@test !(A.processed)
+doctest(
+    joinpath(@__DIR__, "src"),
+    [PluginsTestModule];
+    plugins=[_RunPluginTests(true), A]
+)
+@test A.processed
+
 end