Ensure to pass an absolute path to the els_uri:uri/1 function (#1357)

The `compile:file/1` function can return a relative path depending on
the directory the emulator is started on. This corner case was
resulting in occasional crashes for the users which prevented
diagnostics to appear if an included file contained errors.

apps/els_lsp/src/els_compiler_diagnostics.erl

@@ -680,18 +680,23 @@ inclusion_range(IncludePath, Document, include) ->
     [Range || #{id := Id, range := Range} <- POIs, Id =:= IncludeId];
 inclusion_range(IncludePath, Document, include_lib) ->
     POIs = els_dt_document:pois(Document, [include_lib]),
-    IncludeId = els_utils:include_lib_id(IncludePath),
+    IncludeId = els_utils:include_lib_id(absolute_path(IncludePath)),
     [Range || #{id := Id, range := Range} <- POIs, Id =:= IncludeId];
 inclusion_range(IncludePath, Document, behaviour) ->
     POIs = els_dt_document:pois(Document, [behaviour]),
-    BehaviourId = els_uri:module(els_uri:uri(els_utils:to_binary(IncludePath))),
+    BehaviourId = els_uri:module(els_uri:uri(els_utils:to_binary(absolute_path(IncludePath)))),
     [Range || #{id := Id, range := Range} <- POIs, Id =:= BehaviourId];
 inclusion_range(IncludePath, Document, parse_transform) ->
     POIs = els_dt_document:pois(Document, [parse_transform]),
     ParseTransformId =
-        els_uri:module(els_uri:uri(els_utils:to_binary(IncludePath))),
+        els_uri:module(els_uri:uri(els_utils:to_binary(absolute_path(IncludePath)))),
     [Range || #{id := Id, range := Range} <- POIs, Id =:= ParseTransformId].
 
+-spec absolute_path(string()) -> string().
+absolute_path(Path) ->
+    {ok, Cwd} = file:get_cwd(),
+    filename:join(Cwd, Path).
+
 -spec macro_options() -> [macro_option()].
 macro_options() ->
     Macros = els_config:get(macros),