new TeX mode (again)

[matthias314]

This patch (hopefully) improves Aspell's TeX mode. It is practically identical to the one posted to the Aspell mailing list in 2011.

New features implemented by this patch

• Aspell skips over math content inside $...$, $$..$$, \(...\), \[...\] and common LaTeX and AMS-LaTeX environments like equation and gather. Additional environments to be skipped over can be defined via the new tex-ignore-env list. Otherwise math formulas trigger a huge number of false alarms.

• Forced spell-checking of macro arguments while skipping over arguments or environments. This is achieved with the new T option to add-tex-command. Remarks added in 2022 about the T option:

  • I guess the T was supposed to mean "toggle". Maybe F for "force" would be a better choice.
  • Would it be better to make this the standard behaviour of the P option? Asked differently: What LaTeX macros are there using P where we don’t want the corresponding argument to be spell checked in math mode? Such a macro should also have arguments without spell checking because otherwise there is no need to define it in Aspell. I can only think of \textcolor{color}{text} from color.sty (where text can also be in math mode!).

• Discretionary hyphens and italic corrections are ignored. For example, hy\-phen and shelf\/ful are recognized as single words.

• Spell-checking can be manually switched on and off by putting the text aspell:on and aspell:off into the file. This allows to skip over macro definitions and other parts of text that confuse Aspell.

See the Info file for more details.

Comments about the changes

./modules/filter/context.cpp It seems that the order of the context filter was undefined. Whether one wants to have this filter before or after other filters depends on the application in mind. I need it before the tex filter so that one can place the aspell:off and aspell:on flags inside TeX comments.

./modules/filter/tex.cpp The new code for the tex filter.

./modules/filter/tex-filter.info The new default settings for the filter variables. tex-ignore-env is new. Most changes to tex-command are related to the new T option. The new begin line is used internally. The rest are additions and corrections to existing definitions.

./modules/filter/modes/tex.amf Note that we enable the context filter by default.

./manual/aspell.1 ./manual/aspell.texi Updated documentation.

[dkwo]

Thanks for your work. I'm unable to apply this patch cleanly on 0.60.8 Is there something I'm missing?

[matthias314]

@dkwo: There have been several (more or less) recent commits fixing typos in the documentation, the latest being #624. They can be ignored. Are there any conflicts regarding the code?

[dkwo]

Applying the file obtained by appending .patch to this PR on top of the 0.60.8 tarball, besides the manual

1 out of 1 hunk FAILED -- saving rejects to file manual/aspell.1.rej 1 out of 5 hunks FAILED -- saving rejects to file manual/aspell.texi.rej

I get this failure:

3 out of 6 hunks FAILED -- saving rejects to file modules/filter/tex.cpp.rej

[matthias314]

@dkwo: That's strange. I've downloaded the patch and the 0.60.8 tar ball. Then

/tmp/aspell-0.60.8$ patch --dry-run --verbose -p1 </tmp/625.patch

gives (among other things)

checking file modules/filter/tex.cpp
Using Plan A...
Hunk #1 succeeded at 32.
Hunk #2 succeeded at 53.
Hunk #3 succeeded at 71.
Hunk #4 succeeded at 99.
Hunk #5 succeeded at 267.
Hunk #6 succeeded at 294.

[dkwo]

My bad, sorry about that. I downloaded the patch again, and now it applies cleanly, if I remove the manuals part. It seems to work fine here, but I have one question. Suppose I want to ignore the \cref command (similar to \eqref and \ref): what is the correct synax to pass aspell?

[matthias314]

To ignore \cref{label}, you put

add-tex-command cref p

into your .aspell.conf file. One could also add a corresponding definition to modules/filter/tex-filter.info, and for many other macros as well.

[dkwo]

Thank you.

[dkwo]

I've been using this for almost a year, can confirm it works well. @kevina any chance it can be merged?

[kevina]

@dkwo @matthias314 my main concern with this is causing a regression. I would be more willing to accept this if it has some test cases. There is now a primitive framework for this is the tests/ directory (see the filter-test target in the Makefile). Ideally I would like to first accept a pull request with some tests for the existing TeX filter to make sure this new filter doesn't break anything.

[kevina]

@matthias314, I am leaning towards accepting this once the above issues are resolved.

[kevina]

To be clear by above issues I mean the two comments in the code review, tests would be nice, but not really required.

[matthias314]

I'm very sorry for my belated reply.

Regarding a potential regression: That's a valid point. I've been using the new TeX mode for many years now, but only on a very limited variety of LaTeX documents. By the same token, I think that if I got around to add test documents, then they would only cover a tiny fraction of the kinds of documents other users have. Would be a possible alternative to add the new TeX mode besides the existing one so that users could fall back to the old version in case the new one causes problems?

[kevina]

Would be a possible alternative to add the new TeX mode besides the existing one so that users could fall back to the old version in case the new one causes problems?

I thought about that, but rejected the idea as being too complicated, but that was many years ago. I'll have another look sometime soonish. Hopefully by the end of the weekend.

[kevina]

Closing in favor of #644