add tree-sitter-embedded-template (erb & ejs) (#2055)

After the incremental parsing rewrite for injections (which was released
in 22.03 https://helix-editor.com/news/release-22-03-highlights/#incremental-injection-parsing-rewrite),
we can now do combined injections which lets us pull in some templating
grammars. The most notable of those is embedded-template - a pretty
straightforward grammar that covers ERB and EJS.

The grammar and highlights queries are shared between the two but they have
different injections.

book/src/generated/lang-support.md

@@ -9,8 +9,10 @@
 | css | ✓ |  |  | `vscode-css-language-server` |
 | dart | ✓ |  | ✓ | `dart` |
 | dockerfile | ✓ |  |  | `docker-langserver` |
+| ejs | ✓ |  |  |  |
 | elixir | ✓ |  |  | `elixir-ls` |
 | elm | ✓ |  |  | `elm-language-server` |
+| erb | ✓ |  |  |  |
 | erlang | ✓ |  |  | `erlang_ls` |
 | fish | ✓ | ✓ | ✓ |  |
 | git-commit | ✓ |  |  |  |

languages.toml

@@ -1088,3 +1088,25 @@ language-server = { command = "sourcekit-lsp" }
 [[grammar]]
 name = "swift"
 source = { git = "https://github.com/Dispersia/tree-sitter-swift", rev = "e75240f89bb3bfd3396155859ae364e5c58d7377" }
+
+[[language]]
+name = "erb"
+scope = "text.html.erb"
+injection-regex = "erb"
+file-types = ["erb"]
+roots = []
+indent = { tab-width = 2, unit = "  " }
+grammar = "embedded-template"
+
+[[language]]
+name = "ejs"
+scope = "text.html.ejs"
+injection-regex = "ejs"
+file-types = ["ejs"]
+roots = []
+indent = { tab-width = 2, unit = "  " }
+grammar = "embedded-template"
+
+[[grammar]]
+name = "embedded-template"
+source = { git = "https://github.com/tree-sitter/tree-sitter-embedded-template", rev = "d21df11b0ecc6fd211dbe11278e92ef67bd17e97" }

runtime/queries/ejs/highlights.scm

@@ -0,0 +1,12 @@
+(comment_directive) @comment
+
+[
+  "<%#"
+  "<%"
+  "<%="
+  "<%_"
+  "<%-"
+  "%>"
+  "-%>"
+  "_%>"
+] @keyword

runtime/queries/ejs/injections.scm

@@ -0,0 +1,7 @@
+((content) @injection.content
+ (#set! injection.language "html")
+ (#set! injection.combined))
+
+((code) @injection.content
+ (#set! injection.language "javascript")
+ (#set! injection.combined))

runtime/queries/erb/highlights.scm

@@ -0,0 +1 @@
+; inherits: ejs

runtime/queries/erb/injections.scm

@@ -0,0 +1,7 @@
+((content) @injection.content
+ (#set! injection.language "html")
+ (#set! injection.combined))
+
+((code) @injection.content
+ (#set! injection.language "ruby")
+ (#set! injection.combined))