Handle gists with file extensions

Somehow, in my Gist Proxy code 7518a035b1 I never accounted for gist
ids with file extensions. For example: `def123.js` instead of plain
`def123`. This is now fixed and articles with those kinds of gists in
them work now.

Reference article:
https://medium.com/neat-tips-tricks/ocaml-continuation-explained-3b73839
b679f

spec/models/gist_params_spec.cr

@@ -10,6 +10,16 @@ describe GistParams do
     params.filename.should eq("example.txt")
   end
 
+  describe "when gist file has a file extension" do
+    it "extracts params from the gist url" do
+      url = "https://gist.github.com/user/1d.js"
+
+      params = GistParams.extract_from_url(url)
+
+      params.id.should eq("1d")
+    end
+  end
+
   describe "when no file param exists" do
     it "does not extract a filename" do
       url = "https://gist.github.com/user/1D"

src/models/gist_params.cr

@@ -9,20 +9,15 @@ class GistParams
 
   def self.extract_from_url(href : String)
     uri = URI.parse(href)
-    maybe_id = Monads::Try(Regex::MatchData)
-      .new(->{ uri.path.match(GIST_ID_REGEX) })
-      .to_maybe
-      .fmap(->(matches : Regex::MatchData) { matches[0] })
-    case maybe_id
-    in Monads::Just
-      id = maybe_id.value!
-    in Monads::Nothing, Monads::Maybe
+    maybe_id = Path.posix(uri.path).stem
+
+    if maybe_id.matches?(GIST_ID_REGEX)
+      id = maybe_id
+      filename = uri.query_params["file"]?
+      new(id: id, filename: filename)
+    else
       raise MissingGistId.new(href)
     end
-
-    filename = uri.query_params["file"]?
-
-    new(id: id, filename: filename)
   end
 
   def initialize(@id : String, @filename : String?)

src/version.cr

@@ -1,3 +1,3 @@
 module Scribe
-  VERSION = "2022-03-12"
+  VERSION = "2022-04-04"
 end