* Make KaTeX work in Quirks mode
Summary: In issue #601, it was noticed that the KaTeX bug with the fraction
bars overlapping the text was occuring with an XHTML doctype. This indicated
that the bug we were seeing was caused by both quirks mode and limited-quirks
mode (which is a version of quirks mode with fewer quirks and is enabled for
various doctypes including some XHTML ones).
Based on the [quirks spec](https://quirks.spec.whatwg.org/), it appears that
there are only two quirks in limited-quirks mode, both having to do with a
line-height calculation. @gagern figured out that if we added some zero-width
spaces in our elements, we would stop triggering the quirk, which would make
our fractions render correctly in limited-quirks mode.
I implemented that change, and ran the screenshotter in limited-quirks mode.
There were several other places that suffered from the same quirk, but were
also easily fixed via adding zero-width spaces. I then ran the screenshotter in
quirks mode, and discovered that (once an appropriate meta charset was added),
everything looked correct still.
So, this diff fixes all of the places that the limited-quirks mode quirks
affect our rendering, and removes the warning about rendering in quirks mode.
I also added support to our screenshotter to render things in both no-quirks
and quirks mode, to ensure that things don't break in the future. I copied the
non-quirks images to the quirks images, and ran the screenshotter with
`--verify` to make sure that they look the same.
I have some thoughts that I'd like to hear opinions about:
- I'm not super happy with how the screenshot tests work. Ideally we'd test
both quirks mode and non-quirks mode against the same images, since we'd
like them to be the same. I'm not sure how to make that work well, though,
since then people wouldn't be able to tell if it's a quirks-mode problem or
not.
- I removed the doctype in the testing page file, so all testing would now be
done in quirks-mode. Not sure if we really want that.
- I need to test this in IE, but it looks like the trailing commas change we
made with eslinting is causing problems (cause IE doesn't like trailing
commas).
Test Plan:
- `./dockers/Screenshotter/screenshotter.sh --verify`
* Compare quirks mode against same screenshot files
Now the screenshotter itself can run more than one mode. It does serve the
HTML file from its own JavaScript code now, so that it can include different
doctype headers without needing distinct files for each. There is a
provision to mark specific tests as quirky in case they produce different
results depending on the mode.
* Some cleaning up and comments
* Restore access to the babelified version of the HTML page for screenshots
* Reference unicode fonts using absolute path names
This avoids issues caused by the fact that the dynamically generated
ss-render.html is mounted to a different location than the test.html from
which it is derived.
* do chrome screenshots first
* remove commented out code, simplify hadle_search_string call
This ensures that running screenshots as indicated by the screenshotter
readme will correctly render the Unicode examples, even if not run on
Travis. It also fixes the commit ID of the unicode fonts.
One alternative would have been using a git submodule. But as many tools
will initialize submodules automatically, that would mean big downloads for
anyone using such a tool to clone KaTeX.
Another alternative would be tweaking the server to fetch the files on
demand if the local copy is unavailable. But that would cause additional
network overhead, so grabbing the files just once should be simpler.
Since boot2docker has been superseded by docker-machine, we need this to
support developers on OS X. The changes to the bash script ensure that we
clean up our containers even if taking screenshots gets hung and requires a
keyboard interrupt, as happens if the IP addresses were guessed incorrectly.
The combination of jspngopt and pako should eliminate possible causes for
different PNG encodings, although the core reason for #325 remains unknown.
Pako has poorer compression rates than native libz, but optimization can
counter that effect, and actually reduce the size of the screenshots.
The screenshots for LimitControls and UnsupportedCmds on Firefox used to
exhibit subpixel rendering before, for reasons unknown. The regenerated
versions don't exhibit this. See #324 for a discussion.
Since the Selenium images are available for download, and downloading them
is usually faster than building them from scratch, this makes taking
screenshots easier. Furthermore, since the Selenium image is not specific
to KaTeX, it could as well be used for other purposes, thus saving space
since a single image can be used in multiple projects.
This change also deals with the non-determinism in the Lap screenshot:
We detect the one known (and accepted) alternate rendering and change the
output file name to Lap_alt in this case. So either Lap or Lap_alt gets
saved to, and if the image is different from both, then one of these files
will show a modification. On the other hand, if it is equal to either of
these, then the matching one will get overwritten, showing no change.
