Don't show completions on nested module identifier

src/fsharp/service/ServiceParsedInputOps.fs

@@ -1127,6 +1127,12 @@ module ParsedInput =
                                 Some (CompletionContext.OpenDeclaration isOpenType)
                             else
                                 None
+
+                        // module Namespace.Top
+                        // module Neste|
+                        | SynModuleDecl.NestedModule (moduleInfo = SynComponentInfo (longId = [ ident ])) when rangeContainsPos ident.idRange pos ->
+                            Some CompletionContext.Invalid
+
                         | _ -> defaultTraverse decl
 
                     member _.VisitType(_path, defaultTraverse, ty) =

vsintegration/tests/UnitTests/CompletionProviderTests.fs

@@ -498,6 +498,25 @@ open type System.Ma
     let expected = ["Management"; "Math"] // both namespace and static type
     VerifyCompletionList(fileContents, "System.Ma", expected, [])
 
+[<Test>]
+let ``No completion on nested module identifier``() =
+    let fileContents = """
+module Namespace.Top
+
+module Nest
+"""
+    VerifyNoCompletionList(fileContents, "Nest")
+
+[<Test>]
+let ``No completion on nested module identifier2``() =
+    let fileContents = """
+namespace N
+
+module Nested =
+    do ()
+"""
+    VerifyNoCompletionList(fileContents, "Nested")
+
 [<Test>]
 let ``No completion on type name at declaration site``() =
     let fileContents = """