feat: tumblr grammar with highlights, injections, and tests

grammar.js

@@ -10,8 +10,64 @@
 export default grammar({
   name: "tumblr",
 
+  extras: _ => [],
+
   rules: {
-    // TODO: add the actual grammar rules
-    source_file: $ => "hello"
-  }
+    template: $ => repeat($._node),
+
+    _node: $ => choice(
+      $.content,
+      $.block_open,
+      $.block_close,
+      $.lang_tag,
+      $.variable,
+    ),
+
+    content: _ => token(prec(-1, /([^{]|\{[^A-Za-z/])+/)),
+
+    block_open: $ => seq(
+      $._block_open_start,
+      $.block_name,
+      optional($.attributes),
+      "}",
+    ),
+
+    block_close: $ => seq(
+      $._block_close_start,
+      $.block_name,
+      "}",
+    ),
+
+    lang_tag: $ => seq(
+      $._lang_start,
+      $.lang_text,
+      "}",
+    ),
+
+    variable: $ => seq(
+      "{",
+      choice(
+        seq($.variable_name, optional(seq("-", $.variable_modifier))),
+        seq($.variable_prefix, ":", $.prefix_argument),
+      ),
+      "}",
+    ),
+
+    attributes: $ => repeat1($.attribute),
+    attribute: $ => seq($._space, $.attribute_name, "=", $.attribute_value),
+    attribute_name: _ => /[A-Za-z_][A-Za-z0-9_-]*/,
+    attribute_value: _ => /"[^"]*"/,
+
+    block_name: _ => /[A-Za-z][A-Za-z0-9_]*/,
+    variable_name: _ => /[A-Z][A-Za-z0-9_]*/,
+    variable_modifier: _ => /[A-Za-z0-9]+/,
+    variable_prefix: _ => choice("text", "color", "font", "image"),
+    prefix_argument: _ => /[A-Za-z][A-Za-z0-9 _-]*/,
+    lang_text: _ => /[^}]+/,
+
+    _block_open_start: _ => /\{[Bb][Ll][Oo][Cc][Kk]:/,
+    _block_close_start: _ => /\{\/[Bb][Ll][Oo][Cc][Kk]:/,
+    _lang_start: _ => /\{[Ll][Aa][Nn][Gg]:/,
+    _space: _ => /[ \t]+/,
+  },
 });