feat(lsp): Support hover on include statements (#1963)

Co-authored-by: Blaine Bublitz <blaine.bublitz@gmail.com>

Author: spotandjake

compiler/src/language_server/hover.re

@@ -125,6 +125,14 @@ let declaration_lens = (ident: Ident.t, decl: Types.type_declaration) => {
   grain_type_code_block(Printtyp.string_of_type_declaration(~ident, decl));
 };
 
+let include_lens = (env: Env.t, path: Path.t) => {
+  let module_decl = Env.find_module(path, None, env);
+  markdown_join(
+    grain_code_block("module " ++ Path.name(path)),
+    module_lens(module_decl),
+  );
+};
+
 let exception_declaration_lens =
     (ident: Ident.t, ext: Types.extension_constructor) => {
   grain_type_code_block(
@@ -176,6 +184,12 @@ let process =
       )
     | [Module({path, decl, loc}), ..._] =>
       send_hover(~id, ~range=Utils.loc_to_range(loc), module_lens(decl))
+    | [Include({env, path, loc}), ..._] =>
+      send_hover(
+        ~id,
+        ~range=Utils.loc_to_range(loc),
+        include_lens(env, path),
+      )
     | _ => send_no_result(~id)
     };
   };

compiler/src/language_server/sourcetree.re

@@ -168,6 +168,11 @@ module type Sourcetree = {
         decl: Types.module_declaration,
         loc: Location.t,
         definition: option(Location.t),
+      })
+    | Include({
+        env: Env.t,
+        path: Path.t,
+        loc: Location.t,
       });
 
   type sourcetree = t(node);
@@ -253,6 +258,11 @@ module Sourcetree: Sourcetree = {
         decl: Types.module_declaration,
         loc: Location.t,
         definition: option(Location.t),
+      })
+    | Include({
+        env: Env.t,
+        path: Path.t,
+        loc: Location.t,
       });
 
   type sourcetree = t(node);
@@ -514,6 +524,24 @@ module Sourcetree: Sourcetree = {
               ...segments^,
             ];
         };
+        let enter_toplevel_stmt = stmt => {
+          switch (stmt.ttop_desc) {
+          | TTopInclude(inc) =>
+            segments :=
+              [
+                (
+                  loc_to_interval(stmt.ttop_loc),
+                  Include({
+                    env: stmt.ttop_env,
+                    path: inc.tinc_path,
+                    loc: stmt.ttop_loc,
+                  }),
+                ),
+                ...segments^,
+              ]
+          | _ => ()
+          };
+        };
       });
     Iterator.iter_typed_program(program);
     create(segments^);