Hadrian: can't build only the users guide
Summary
Hadrian can't build only the users guide.
Steps to reproduce
On a fresh checkout of b7efdb24:
> ./boot
> ./configure
> ./hadrian/build _build/doc/users_guide.pdf
...
| Run Sphinx LatexMode: docs/users_guide => /tmp/extra-dir-1490469546388
Command line: /usr/bin/sphinx-build -b latex -d /tmp/extra-dir-1490469546388/.doctrees-latex -n -w /tmp/extra-dir-1490469546388/.log docs/users_guide /tmp/extra-dir-1490469546388
===> Command failed with error code: 2
Exception occurred:
File "/home/hsyl20/projects/ghc/fresh/docs/users_guide/ghc_packages.py", line 10, in read_cabal_file
cabal_file = open(pkg_path, 'r').read()
FileNotFoundError: [Errno 2] No such file or directory: 'compiler/ghc.cabal'
The full traceback has been saved in /tmp/sphinx-err-8y_1frmt.log, if you want to report the issue to the developers.
Please also report this if it was a user error, so that a better error message can be provided next time.
A bug report can be filed in the tracker at <https://github.com/sphinx-doc/sphinx/issues>. Thanks!
Running Sphinx v5.3.0
building [mo]: targets for 0 po files that are out of date
building [latex]: all documents
updating environment: [new config] 160 added, 0 changed, 0 removed
reading sources... [ 0%] 9.6.1-notes
Command failed
Build failed.
Expected behavior
Build the users guide.