Should update to tree-sitter-markdown

[bennypowers]

Prerequisites

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Description

language-gfm uses the old textmate grammar for markdown, which means it's using the oold grammars for embedded languages as well. language-gfm should use an up-to-date tree sitter grammar, e.g. tree-sitter-markdown

Steps to Reproduce

1. Use language-gfm
2. embedded grammars may not support up-to-date features, e.g. ?. ?? optional chaining and nullish coalescing in JavaScript

Expected behavior:

JavaScript with embedded html, itself embedded in markdown should render like:

Actual behavior:

Reproduces how often:

100%

Versions

atom --version

Atom : 1.58.0 Electron: 9.4.4 Chrome : 83.0.4103.122 Node : 12.14.1 apm 2.6.2 npm 6.14.13 node 12.14.1 x64 atom 1.58.0 python 2.7.16 git 2.28.0

Additional Information