Digestif

Digestif is a code analyzer, and a language server, for LaTeX, ConTeXt et caterva. It provides context-sensitive completion, documentation, code navigation, and related functionality to any text editor that speaks the LSP protocol.

Check it out online: Digestif is the autocompletion engine of the SwiftLaTeX web-based editor.

Features

• Completion for commands, environments, key-value options (for instance, TikZ options), cross-references and citations.

• Popup help messages, including command signature and documentation. For the best results, make sure you have the LaTeX reference manual installed as an info node.

• Find definition and references to labels and citations.

• Document outline.

• Multi-file documents are supported via TeXShop-style magic comments. Just add a comment like this near the top of each child document:

  % !TeX root = somefile.tex
  

• Digestif is fuzzy! For citations, it tries an exact match against the BibTeX identifier and a fuzzy match against author and title. In the GIF above, the user types groalhom, which matches Grothendieck's “Sur quelques points d'algébre homologique”; selecting this inserts the BibTeX identifier Tohoku. Similarly, for cross-references, Digestif tries an exact match against the label and a fuzzy match against the text around the label.

• Support for LaTeX, ConTeXt, plain TeX and Texinfo.

• Bibliography support via BibTeX and amsrefs.

• Lua API, independent of the language server protocol, for use in editors capable of loading Lua modules. See API on the wiki for details.

Installation and set-up

Digestif has minimal dependencies and can run on LuaTeX or on a standalone Lua interpreter. Correspondingly, there are two ways to install it.

• For LuaTeX with the self-installing script: The only dependencies for this are git and a recent TeX installation.

  1. Download the digestif wrapper script.
  2. Place it in your $PATH (say, ~/.local/bin).
  3. Make it executable (chmod +x ~/.local/bin/digestif).

  In the first run, the script will automatically download the package, by default to ~/.digestif. To update or uninstall, simply delete that folder.

• For standalone Lua via LuaRocks: Run luarocks install digestif. This should be done either as root or with the --local option, in which case the executable script will land in ~/.luarocks/bin/digestif; make sure this is in your $PATH or adapt your text editor configuration accordingly.

Next, you need to enable Digestif as a language server in your favorite text editor.

• Emacs with the Eglot package: Digestif works out-of-the-box with Eglot. Just install the package (M-x package-install RET eglot RET), open some TeX document and enable Eglot (M-x eglot). Voilà! Make sure to activate yas-minor-mode before starting up Eglot if you want to have code snippets inserted automatically after choosing a completion candidate.

• Emacs with the lsp-mode package: Just add

  (setq lsp-tex-server 'digestif)

  to your init file to ensure that Digestif is used.

• Vim with the Coc plugin: See instructions here.

Supported TeX packages

Digestif tries to learn about the commands provided by a package by looking at its source code, but this has limitations, since the typical TeX literate documentation is ostensibly not machine readable.

For full support, a detailed “tags” file should be created for each package. Among other things, this file lists all defined macros together with their signatures and docstrings. To generate a stub tags file from a .sty, .cls or .dtx file, use the command

digestif --generate FILES

After filling in the missing details, the resulting tags file can be added to this repository (pull requests are welcome!). The format of the tags files should be more or less self explanatory. See the data folder for examples.

License

The Digestif program and library, that is, everything outside the data folder, are available under the MIT license.

Some files in the data folder are extracted or adapted from other sources, such as source code, manuals or reference materials, and therefore may inherit specific licensing details. At a minimum, they are free to use and redistribute. When no restriction exists, the MIT license also applies.