Add support for `Roc` language (#1197)

languages.json

@@ -1498,6 +1498,15 @@
       "blank": true,
       "extensions": ["rst"]
     },
+    "Roc": {
+      "line_comment": ["#"],
+      "quotes": [
+        ["\\\"", "\\\""],
+        ["'", "'"]
+      ],
+      "doc_quotes": [["\\\"\\\"\\\"", "\\\"\\\"\\\""]],
+      "extensions": ["roc"]
+    },
     "RON": {
       "name": "Rusty Object Notation",
       "line_comment": ["//"],

tests/data/roc.roc

@@ -0,0 +1,36 @@
+# 36 lines 18 code 10 comments 8 blanks
+module [square]
+# this is a comment
+# this is another comment
+
+a1 = 1
+a2 = 3.14159 # pi
+
+expect
+    # simple check
+    a1 == 1
+
+expect
+    a2 |> Num.toStr == "3.14159"
+
+## Compute the square
+square = \x ->
+    s = x * x
+
+    # the line above is blank
+    s
+
+expect square 3 == 9
+
+## """
+## this is not a multiline string,
+## it's a doc comment
+## """
+multilineString =
+    """
+    # this line is not a comment, it's actually code
+
+    The line above is not blank, it's actually code
+    """
+
+expect multilineString |> Str.toUtf8 |> List.first == Ok '#'