fix rstudio#1160: allow the site field to be quoted in YAML

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: bookdown
 Type: Package
 Title: Authoring Books and Technical Documents with R Markdown
-Version: 0.22.2
+Version: 0.22.3
 Authors@R: c(
     person("Yihui", "Xie", role = c("aut", "cre"), email = "[email protected]", comment = c(ORCID = "0000-0003-0645-5666")),
     person("JJ", "Allaire", role = "ctb"),

NEWS.md

@@ -12,8 +12,11 @@
   ````
 
   However, as _beamer_ defines its own LaTeX throem environments, **bookdown** won't add any definition in preamble as it is doing with `pdf_book()`. This means user will have to define the ones supported by **bookdown** and not yet defined by _beamer_. Special environment from _beamer_ (like `fact`) needs to be used with usual [Custom Blocks syntax](https://bookdown.org/yihui/rmarkdown-cookbook/custom-blocks.html). See related issues for examples in their discussions thread (thanks, @XiangyunHuang, #1143, #1145).
+
   This change comes with several small improvements in `custom-enviromnent.lua` for `latex` and `beamer` format, including a new option `bookdown.theorem.preamble` to opt-out **bookdown** addition of theorems and proofs definitions in LaTeX preamble. Set it to `FALSE` if you have conflict with some specific format for example (like #1001).
-
+
+- When the `site` field is quoted in `index.Rmd`'s YAML data (i.e., `site: "bookdown::bookdown_site"`), **bookdown** fails to identify the root directory of the book (thanks, @dchiu911, #1160).
+
 # CHANGES IN bookdown VERSION 0.22
 
 ## NEW FEATURES

R/site.R

@@ -86,7 +86,7 @@ find_book_name = function(config, default) {
 find_book_proj = function(input) {
   # if bookdown_site() is executed it is because site: has been set in index.Rmd
   rules = matrix(c(
-    '^index.Rmd$', '^\\s*site:\\s*bookdown::bookdown_site\\s*$'
+    '^index.Rmd$', '^\\s*site:\\s*["\']?bookdown::bookdown_site["\']?\\s*$'
   ), ncol = 2, byrow = TRUE, dimnames = list(NULL, c('file', 'pattern')))
   xfun::proj_root(input, rules)
 }