Bug#886285: vim-runtime: tex syntax highlighting fails to enter math mode within align environment

[Francesco Poli (wintermute)]

Package: vim-runtime
Version: 2:8.0.1401-2
Severity: normal

Hello again!

I noticed another regression, this time in tex syntax highlighting.
The issue seems to be that it fails to enter math mode within the align
environment (and probably other amsmath environments).

The package version currently in buster and sid
(vim-runtime/2:8.0.1401-2) messes up with the highlighting of the math
between \begin{align} and \end{align}, while it correctly deals with the
math between \begin{equation} and \end{equation}.
This is shown in the first attached screenshot.

On the other hand, vim-runtime/2:8.0.0197-4+deb9u1 (which is in stretch),
behaves correctly, as shown in the second attached screenshot.

The two screenshots were obtained (on buster and stretch, respectively)
with

  $ view -u NONE test_align.tex

followed by

 :syn on 
 :set bg=dark


Please fix the bug and/or forward this report upstream, as appropriate.

Thanks for your time!
Bye.


-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (800, 'testing'), (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.14.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

vim-runtime depends on no packages.

Versions of packages vim-runtime recommends:
ii  vim            2:8.0.1401-2
ii  vim-gtk [vim]  2:8.0.1401-2
ii  vim-tiny       2:8.0.1401-2

vim-runtime suggests no packages.

-- no debconf information
-------------- next part --------------
\documentclass[a4paper,12pt]{article}
\usepackage{amsmath}
\begin{document}
\begin{align}
  a_x & = b_x \\
  a_y & = b_y
\end{align}
\begin{equation}
  a_z = 0  \qquad b_z \neq 0
\end{equation}
\end{document}
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