From d6e9afd3d6c0434d07ed483db58b94ccf1cb7321 Mon Sep 17 00:00:00 2001
From: Alex Perkins <alex.perkins@noredink.com>
Date: Fri, 1 Apr 2022 11:44:43 -0400
Subject: [PATCH] add support for Elm

---
 build.rs                      |  5 ++++
 sample_files/compare.expected |  3 +++
 sample_files/elm_after.elm    | 40 ++++++++++++++++++++++++++++++++
 sample_files/elm_before.elm   | 43 +++++++++++++++++++++++++++++++++++
 src/guess_language.rs         |  3 +++
 src/tree_sitter_parser.rs     | 15 ++++++++++++
 vendor/highlights/elm.scm     |  1 +
 vendor/tree-sitter-elm-src    |  1 +
 8 files changed, 111 insertions(+)
 create mode 100644 sample_files/elm_after.elm
 create mode 100644 sample_files/elm_before.elm
 create mode 120000 vendor/highlights/elm.scm
 create mode 120000 vendor/tree-sitter-elm-src

diff --git a/build.rs b/build.rs
index 977a0a518..9bf397879 100644
--- a/build.rs
+++ b/build.rs
@@ -109,6 +109,11 @@ fn main() {
             src_dir: "vendor/tree-sitter-gleam-src",
             extra_files: vec![],
         },
+        TreeSitterParser {
+            name: "tree-sitter-elm",
+            src_dir: "vendor/tree-sitter-elm-src",
+            extra_files: vec!["scanner.cc"],
+        },
         TreeSitterParser {
             name: "tree-sitter-go",
             src_dir: "vendor/tree-sitter-go-src",
diff --git a/sample_files/compare.expected b/sample_files/compare.expected
index e1cd29508..70eb7d262 100644
--- a/sample_files/compare.expected
+++ b/sample_files/compare.expected
@@ -28,6 +28,9 @@ f4233ebbe6c46a7c07bc88eca20e4856  -
 sample_files/elisp_contiguous_before.el sample_files/elisp_contiguous_after.el
 e3946aef566a707c718edd7a86340566  -
 
+sample_files/elm_before.elm sample_files/elm_after.elm
+16777d5b5204b34cf7891b9fd476d9fc  -
+
 sample_files/hack_before.php sample_files/hack_after.php
 b8c51005df7e1eaaeaf738a4353ac88f  -
 
diff --git a/sample_files/elm_after.elm b/sample_files/elm_after.elm
new file mode 100644
index 000000000..fa8f4e146
--- /dev/null
+++ b/sample_files/elm_after.elm
@@ -0,0 +1,40 @@
+module Main exposing (blue, list, x, y)
+
+
+list : List Int
+list =
+    [ 1
+    , 2
+    , 3
+    , 4
+    ]
+
+
+blue : a -> String
+blue =
+    \_ -> "blue"
+
+
+green : String
+green =
+    "yellow" ++ "blue"
+
+
+x : Int
+x =
+    (*) 2 <| 4
+
+
+y : Int
+y =
+    4 |> (*) 2
+
+
+fn :
+    ()
+    -> Int
+    -> List String
+    -> ()
+    -> String
+fn () n strings () =
+    String.join (String.fromInt n) strings
diff --git a/sample_files/elm_before.elm b/sample_files/elm_before.elm
new file mode 100644
index 000000000..60d77a6df
--- /dev/null
+++ b/sample_files/elm_before.elm
@@ -0,0 +1,43 @@
+module Main exposing (blue, green, list, x, y, z)
+
+
+list : List Int
+list =
+    [ 1, 2, 3 ]
+
+
+blue : a -> String
+blue =
+    always "blue"
+
+
+green : a -> String
+green =
+    always "blue"
+
+
+y : Int
+
+
+x =
+    (*) 2 4
+
+
+y : Int
+y =
+    (*) 2 4
+
+
+z : String
+z =
+    "abc"
+
+
+fn : () -> Int -> List String -> String
+fn _ n strings =
+    let
+        foo : List String -> String
+        foo =
+            String.join (String.fromInt n)
+    in
+    foo strings
diff --git a/src/guess_language.rs b/src/guess_language.rs
index 82e2d829f..e0bdc528e 100644
--- a/src/guess_language.rs
+++ b/src/guess_language.rs
@@ -27,6 +27,7 @@ pub enum Language {
     Css,
     Dart,
     Elixir,
+    Elm,
     EmacsLisp,
     Gleam,
     Go,
@@ -99,6 +100,7 @@ fn from_emacs_mode_header(src: &str) -> Option<Language> {
             "dart" => Some(Dart),
             "c++" => Some(CPlusPlus),
             "elixir" => Some(Elixir),
+            "elm" => Some(Elm),
             "emacs-lisp" => Some(EmacsLisp),
             "gleam" => Some(Gleam),
             "go" => Some(Go),
@@ -196,6 +198,7 @@ pub fn from_extension(extension: &OsStr) -> Option<Language> {
         "css" => Some(Css),
         "dart" => Some(Dart),
         "el" => Some(EmacsLisp),
+        "elm" => Some(Elm),
         "ex" | "exs" => Some(Elixir),
         "gleam" => Some(Gleam),
         "go" => Some(Go),
diff --git a/src/tree_sitter_parser.rs b/src/tree_sitter_parser.rs
index e1b40929c..4acb63045 100644
--- a/src/tree_sitter_parser.rs
+++ b/src/tree_sitter_parser.rs
@@ -54,6 +54,7 @@ extern "C" {
     fn tree_sitter_elisp() -> ts::Language;
     fn tree_sitter_elixir() -> ts::Language;
     fn tree_sitter_gleam() -> ts::Language;
+    fn tree_sitter_elm() -> ts::Language;
     fn tree_sitter_go() -> ts::Language;
     fn tree_sitter_haskell() -> ts::Language;
     fn tree_sitter_janet_simple() -> ts::Language;
@@ -256,6 +257,20 @@ pub fn from_language(language: guess::Language) -> TreeSitterConfig {
                 .unwrap(),
             }
         }
+        Elm => {
+            let language = unsafe { tree_sitter_elm() };
+            TreeSitterConfig {
+                name: "Elm",
+                language,
+                atom_nodes: vec!["string_constant_expr"].into_iter().collect(),
+                delimiter_tokens: vec![("{", "}"), ("[", "]"), ("(", ")")],
+                highlight_query: ts::Query::new(
+                    language,
+                    include_str!("../vendor/highlights/elm.scm"),
+                )
+                .unwrap(),
+            }
+        }
         Go => {
             let language = unsafe { tree_sitter_go() };
             TreeSitterConfig {
diff --git a/vendor/highlights/elm.scm b/vendor/highlights/elm.scm
new file mode 120000
index 000000000..6a19b68cf
--- /dev/null
+++ b/vendor/highlights/elm.scm
@@ -0,0 +1 @@
+../tree-sitter-elm/queries/highlights.scm
\ No newline at end of file
diff --git a/vendor/tree-sitter-elm-src b/vendor/tree-sitter-elm-src
new file mode 120000
index 000000000..b2445e8b2
--- /dev/null
+++ b/vendor/tree-sitter-elm-src
@@ -0,0 +1 @@
+tree-sitter-elm/src
\ No newline at end of file