complete modules in payload of mainTypeForModule

Author: zth

analysis/src/CompletionFrontEnd.ml

@@ -946,6 +946,32 @@ let completionWithParser1 ~currentFile ~debug ~offset ~path ~posCursor
            setResult
              (Completable.CdecoratorPayload
                 (JsxConfig {nested = List.rev nested; prefix})))
+       | _ -> ()
+     else if id.txt = "mainTypeForModule" then
+       match payload with
+       | PStr
+           [
+             {
+               pstr_desc =
+                 Pstr_eval
+                   ( {
+                       pexp_loc;
+                       pexp_desc = Pexp_construct ({txt = path; loc}, None);
+                     },
+                     _ );
+             };
+           ]
+         when locHasCursor pexp_loc ->
+         if Debug.verbose () then
+           print_endline "[decoratorCompletion] Found @mainTypeForModule";
+         setResult
+           (Completable.Cpath
+              (CPId
+                 {
+                   path = Utils.flattenLongIdent path;
+                   completionContext = Module;
+                   loc;
+                 }))
        | _ -> ());
     Ast_iterator.default_iterator.attribute iterator (id, payload)
   in

analysis/tests/src/CompletionFromModule.res

@@ -34,3 +34,6 @@ let nn: SomeOtherModule.t = {nname: "hello"}
 // nn.
 //    ^com
 // ^dv-
+
+// @mainTypeForModule(SomeOthe) type typeOutsideModule = {nname: string}
+//                            ^com

analysis/tests/src/expected/CompletionFromModule.res.txt

@@ -35,7 +35,7 @@ Path SomeModule.
 
 Complete src/CompletionFromModule.res 33:6
 posCursor:[33:6] posNoWhite:[33:5] Found expr:[33:3->33:6]
-Pexp_field [33:3->33:5] _:[37:0->33:6]
+Pexp_field [33:3->33:5] _:[40:0->33:6]
 [set_result] set new result to Cpath Value[nn].""
 Completable: Cpath Value[nn].""
 Package opens Pervasives.JsxModules.place holder
@@ -77,3 +77,18 @@ Path SomeOtherModule.
   }]
 
 
+Complete src/CompletionFromModule.res 37:30
+XXX Not found!
+Completable: Cpath Module[SomeOthe]
+Package opens Pervasives.JsxModules.place holder
+Resolved opens 1 pervasives
+ContextPath Module[SomeOthe]
+Path SomeOthe
+[{
+    "label": "SomeOtherModule",
+    "kind": 9,
+    "tags": [],
+    "detail": "module SomeOtherModule",
+    "documentation": null
+  }]
+