Remove multiline math environments

[vmartinv]

This change allows removing math environments correctly when they are displayed across several lines or in a single line, i.e.

\[
  x + y = 3
\]
or
\[x + y = 3\]

The current implementation has a bug described below. It is also using replaceAll but by default it doesn't match across several lines. The flag (?s) enables multiline matching. This should solve the bug, and the issues #215 and #227.

Debugging

To discover what was happening I added some prints in the function removeEnvironments for the case in issue215.tex:

line is end of environment: \[\int_{1}^{2}x \mathrm{d}x}\]
line is start of environment:  \begin{tikzpicture}
line is end of environment:  \end{tikzpicture}
line is start of environment:  \[
line is end of environment:  \]
line is end of environment:  \[\int_{1}^{2}x \mathrm{d}x}\]

As you can see the line is detected as end of environment but not as a start, causing a mess. The reason for this is that the regex for isEnvironmentStart is not matching when it should. So there are actually two solutions:

• The one I'm proposing here. I find this approach more simple.
• Modifying isEnvironmentEnd to also not match for single line equations. But then \( \) would need fixing as well.

[vmartinv]

Not sure why that other test is failing. I can't reproduce it locally and it seems unrelated, maybe it is flaky?

[sylvainhalle]

Indeed, it is peculiar that the build fails only for Java 17. Moreover, the failure is on a test that seems completely unrelated to your changes. Let me look into this tomorrow.

[vmartinv]

I was able to reproduce it in docker locally. The tests are failing due to timeout, is not related to this diff. Maybe we can increase the timeout? This particular test has already a timeout set (code)

[sylvainhalle]

I agree, let's just increase the timeout!