Test that articles are built reproducible by default

Author: salim-b

Diff for: tests/testthat/_snaps/build-articles.md

@@ -121,3 +121,10 @@
       Reading vignettes/html-deps.Rmd
       Writing articles/html-deps.html
 
+# output is reproducible by default, i.e. 'seed' is respected
+
+    Code
+      cat(output)
+    Output
+      ## [1] 0.080750138 0.834333037 0.600760886 0.157208442 0.007399441
+

Diff for: tests/testthat/assets/articles/vignettes/random.Rmd

@@ -0,0 +1,7 @@
+---
+title: "Random"
+---
+
+```{r, repro}
+runif(5L)
+```

Diff for: tests/testthat/test-build-articles.R

@@ -215,3 +215,16 @@ test_that("check doesn't include getting started vignette", {
 
   expect_error(data_articles_index(pkg), NA)
 })
+
+test_that("output is reproducible by default, i.e. 'seed' is respected", {
+  pkg <- local_pkgdown_site(test_path("assets/articles"))
+  suppressMessages(build_article(pkg = pkg, name = "random"))
+
+  output <- xml2::read_html(file.path(pkg$dst_path, "articles/random.html")) %>%
+    rvest::html_node("div.contents > pre") %>%
+    rvest::html_text() %>%
+    # replace line feeds with whitespace to make output platform independent
+    gsub("\r", "", .)
+
+  expect_snapshot(cat(output))
+})

Diff for: tests/testthat/test-check.R

@@ -14,7 +14,7 @@ test_that("fails if article index incomplete", {
   pkg <- local_pkgdown_site(test_path("assets/articles"), meta = "
     articles:
      - title: Title
-       contents: [starts_with('html'), standard, toc-false, widget]
+       contents: [starts_with('html'), random, standard, toc-false, widget]
   ")
   expect_snapshot(check_pkgdown(pkg), error = TRUE)
 })