Checker: report environment before checking namespace (#18609)

Author: auduchinok

docs/release-notes/.FSharp.Compiler.Service/10.0.100.md

@@ -7,6 +7,7 @@
 * Allow `let!` and `use!` type annotations without requiring parentheses ([PR #18508](https://github.com/dotnet/fsharp/pull/18508))
 * Fix find all references for F# exceptions ([PR #18565](https://github.com/dotnet/fsharp/pull/18565))
 * Shorthand lambda: fix completion for chained calls and analysis for unfinished expression ([PR #18560](https://github.com/dotnet/fsharp/pull/18560))
+* Completion: fix previous namespace considered opened [PR #18609](https://github.com/dotnet/fsharp/pull/18609)
 
 ### Breaking Changes
 

src/Compiler/Checking/CheckDeclarations.fs

@@ -5428,6 +5428,7 @@ let rec TcModuleOrNamespaceElementNonMutRec (cenv: cenv) parent typeNames scopem
 
           let envNS = LocateEnv kind.IsModule cenv.thisCcu env enclosingNamespacePath
           let envNS = ImplicitlyOpenOwnNamespace cenv.tcSink g cenv.amap m enclosingNamespacePath envNS
+          CallEnvSink cenv.tcSink (m, envNS.NameEnv, env.eAccessRights)
 
           let modTyNS = envNS.eModuleOrNamespaceTypeAccumulator.Value
           let modTyRoot, modulNSs = BuildRootModuleType enclosingNamespacePath envNS.eCompPath modTyNS

tests/FSharp.Compiler.Service.Tests/Common.fs

@@ -5,9 +5,9 @@ open System
 open System.Diagnostics
 open System.IO
 open System.Collections.Generic
-open System.Threading
 open System.Threading.Tasks
 open FSharp.Compiler.CodeAnalysis
+open FSharp.Compiler.EditorServices
 open FSharp.Compiler.IO
 open FSharp.Compiler.Symbols
 open FSharp.Compiler.Syntax
@@ -352,6 +352,14 @@ let getCursorPosAndPrepareSource (source: string) : string * string * pos =
     let lineText = lineText.Replace("{caret}", "")
     source, lineText, Position.mkPos (line + 1) (column - 1)
 
+let getPartialIdentifierAndPrepareSource source =
+    let source, lineText, pos = getCursorPosAndPrepareSource source
+    let _, column, _ = QuickParse.GetCompleteIdentifierIsland false lineText pos.Column |> Option.get
+    let pos = Position.mkPos pos.Line column
+    let plid = QuickParse.GetPartialLongNameEx(lineText, column - 1)
+    let names = plid.QualifyingIdents @ [plid.PartialIdent]
+    source, lineText, pos, plid, names
+
 let getParseResults (source: string) =
     parseSourceCode("Test.fsx", source)
 

tests/FSharp.Compiler.Service.Tests/CompletionTests.fs

@@ -13,11 +13,17 @@ let getCompletionInfo source =
 let getCompletionItemNames (completionInfo: DeclarationListInfo) =
     completionInfo.Items |> Array.map (fun item -> item.NameInCode)
 
-let assertHasItemWithNames names (completionInfo: DeclarationListInfo) =
+let private assertItemsWithNames contains names (completionInfo: DeclarationListInfo) =
     let itemNames = getCompletionItemNames completionInfo |> set
 
     for name in names do
-        Assert.True(Set.contains name itemNames, $"{name} not found in {itemNames}")
+        Assert.True(Set.contains name itemNames = contains)
+
+let assertHasItemWithNames names (completionInfo: DeclarationListInfo) =
+    assertItemsWithNames true names completionInfo
+
+let assertHasNoItemsWithNames names (completionInfo: DeclarationListInfo) =
+    assertItemsWithNames false names completionInfo
 
 [<Fact>]
 let ``Expr - After record decl 01`` () =
@@ -353,4 +359,24 @@ module rec M =
 
     let _: R{caret} = ()
 """
-    assertHasItemWithNames ["Rec1"; "Rec2"; "Rec3"] info
+    assertHasItemWithNames ["Rec1"; "Rec2"; "Rec3"] info
+
+[<Fact>]
+let ``Not in scope 01`` () =
+    let info =
+        getCompletionInfo """
+namespace Ns1
+
+type E =
+    | A = 1
+    | B = 2
+    | C = 3
+
+namespace Ns2
+
+module Module =
+    match Ns1.E.A with
+    | {caret}
+
+"""
+    assertHasNoItemsWithNames ["E"] info

tests/FSharp.Compiler.Service.Tests/ProjectAnalysisTests.fs

@@ -4362,7 +4362,7 @@ let ``Test Project32 should be able to find impl symbols`` () =
         checker.GetBackgroundCheckResultsForFileInProject(Project32.fileName1, Project32.options)
         |> Async.RunImmediate
 
-    let implSymbolUseOpt = implBackgroundTypedParse1.GetSymbolUseAtLocation(3,5,"",["func"])
+    let implSymbolUseOpt = implBackgroundTypedParse1.GetSymbolUseAtLocation(3,5,"let func x = x + 1",["func"])
     let implSymbol = implSymbolUseOpt.Value.Symbol
 
     let usesOfImplSymbol =