If a hook function neither calls the callback nor returns a
(non-undefined) value then there's no way for the hook system to know
if/when the hook function has finished.
`getPadAccess()` (src/node/padaccess.js) is now "promise only", resolving to
`true` or `false` as appropriate, and throwing an exception if there's an
error.
The two call sites (padreadonly.js and importexport.js) updated to match.
This change is only cosmetic. Its aim is do make it easier to understand the
async changes that are going to be merged later on. It was extracted from the
original work from Ray Bellis.
To verify that nothing has changed, you can run the following command on each
file touched by this commit:
npm install uglify-es
diff --unified <(uglify-js --beautify bracketize <BEFORE.js>) <(uglify-js --beautify bracketize <AFTER.js>)
This is a complete script that does the same automatically (works from a
mercurial clone):
```bash
#!/usr/bin/env bash
set -eu
REVISION=<THIS_REVISION>
PARENT_REV=$(hg identify --rev "${REVISION}" --template '{p1rev}')
FILE_LIST=$(hg status --no-status --change ${REVISION})
UGLIFYJS="node_modules/uglify-es/bin/uglifyjs"
for FILE_NAME in ${FILE_LIST[@]}; do
echo "Checking ${FILE_NAME}"
diff --unified \
<("${UGLIFYJS}" --beautify bracketize <(hg cat --rev "${PARENT_REV}" "${FILE_NAME}")) \
<("${UGLIFYJS}" --beautify bracketize <(hg cat --rev "${REVISION}" "${FILE_NAME}"))
done
```
