Restructure NameResolution (#4471)

src/fsharp/NameResolution.fsi

@@ -451,13 +451,13 @@ type ResultCollectionSettings =
 | AtMostOneResult
 
 /// Resolve a long identifier to a namespace or module.
-val internal ResolveLongIndentAsModuleOrNamespace   : TcResultsSink -> ResultCollectionSettings -> Import.ImportMap -> range -> FullyQualifiedFlag -> NameResolutionEnv -> AccessorDomain -> Ident list -> isOpenDecl: bool -> ResultOrException<(int * ModuleOrNamespaceRef * ModuleOrNamespaceType) list >
+val internal ResolveLongIndentAsModuleOrNamespace   : TcResultsSink -> ResultCollectionSettings -> Import.ImportMap -> range -> bool -> FullyQualifiedFlag -> NameResolutionEnv -> AccessorDomain -> Ident -> Ident list -> isOpenDecl: bool -> ResultOrException<(int * ModuleOrNamespaceRef * ModuleOrNamespaceType) list >
 
 /// Resolve a long identifier to an object constructor.
 val internal ResolveObjectConstructor               : NameResolver -> DisplayEnv -> range -> AccessorDomain -> TType -> ResultOrException<Item>
 
 /// Resolve a long identifier using type-qualified name resolution.
-val internal ResolveLongIdentInType                 : TcResultsSink -> NameResolver -> NameResolutionEnv -> LookupKind -> range -> AccessorDomain -> Ident list -> FindMemberFlag -> TypeNameResolutionInfo -> TType -> Item * Ident list
+val internal ResolveLongIdentInType                 : TcResultsSink -> NameResolver -> NameResolutionEnv -> LookupKind -> range -> AccessorDomain -> Ident -> FindMemberFlag -> TypeNameResolutionInfo -> TType -> Item * Ident list
 
 /// Resolve a long identifier when used in a pattern.
 val internal ResolvePatternLongIdent                : TcResultsSink -> NameResolver -> WarnOnUpperFlag -> bool -> range -> AccessorDomain -> NameResolutionEnv -> TypeNameResolutionInfo -> Ident list -> Item

src/fsharp/TypeChecker.fs

@@ -697,13 +697,16 @@ let ImplicitlyOpenOwnNamespace tcSink g amap scopem enclosingNamespacePath env =
             | Some(_, rest) -> rest
             | None -> enclosingNamespacePath
 
-        let ad = env.eAccessRights
-        match ResolveLongIndentAsModuleOrNamespace tcSink ResultCollectionSettings.AllResults amap scopem OpenQualified env.eNameResEnv ad enclosingNamespacePathToOpen true with 
-        | Result modrefs -> 
-            let modrefs = List.map p23 modrefs
-            let openDecl = OpenDeclaration.Create (enclosingNamespacePathToOpen, modrefs, scopem, true)
-            OpenModulesOrNamespaces tcSink g amap scopem false env modrefs openDecl
-        | Exception _ ->  env
+        match enclosingNamespacePathToOpen with
+        | id::rest ->
+            let ad = env.eAccessRights
+            match ResolveLongIndentAsModuleOrNamespace tcSink ResultCollectionSettings.AllResults amap scopem true OpenQualified env.eNameResEnv ad id rest true with 
+            | Result modrefs -> 
+                let modrefs = List.map p23 modrefs
+                let openDecl = OpenDeclaration.Create (enclosingNamespacePathToOpen, modrefs, scopem, true)
+                OpenModulesOrNamespaces tcSink g amap scopem false env modrefs openDecl
+            | Exception _ -> env
+        | _ -> env
 
 
 //-------------------------------------------------------------------------
@@ -6805,7 +6808,7 @@ and TcConstExpr cenv overallTy env m tpenv c  =
         let expr = 
             let modName = "NumericLiteral" + suffix
             let ad = env.eAccessRights
-            match ResolveLongIndentAsModuleOrNamespace cenv.tcSink ResultCollectionSettings.AtMostOneResult cenv.amap m OpenQualified env.eNameResEnv ad [ident (modName, m)] false with 
+            match ResolveLongIndentAsModuleOrNamespace cenv.tcSink ResultCollectionSettings.AtMostOneResult cenv.amap m true OpenQualified env.eNameResEnv ad (ident (modName, m)) [] false with 
             | Result []
             | Exception _ -> error(Error(FSComp.SR.tcNumericLiteralRequiresModule(modName), m))
             | Result ((_, mref, _) :: _) -> 
@@ -10632,13 +10635,13 @@ and TcAttribute canFail cenv (env: TcEnv) attrTgt (synAttr: SynAttribute)  =
                   attributeAssignedNamedItems |> List.map (fun (CallerNamedArg(id, CallerArg(argtyv, m, isOpt, callerArgExpr))) ->
                     if isOpt then error(Error(FSComp.SR.tcOptionalArgumentsCannotBeUsedInCustomAttribute(), m))
                     let m = callerArgExpr.Range
-                    let setterItem, _ = ResolveLongIdentInType cenv.tcSink cenv.nameResolver env.NameEnv LookupKind.Expr m ad [id] IgnoreOverrides TypeNameResolutionInfo.Default ty
+                    let setterItem, _ = ResolveLongIdentInType cenv.tcSink cenv.nameResolver env.NameEnv LookupKind.Expr m ad id IgnoreOverrides TypeNameResolutionInfo.Default ty
                     let nm, isProp, argty = 
                       match setterItem with   
                       | Item.Property (_, [pinfo]) -> 
                           if not pinfo.HasSetter then 
                             errorR(Error(FSComp.SR.tcPropertyCannotBeSet0(), m))
-                          id.idText, true, pinfo.GetPropertyType(cenv.amap, m) 
+                          id.idText, true, pinfo.GetPropertyType(cenv.amap, m)
                       | Item.ILField finfo -> 
                           CheckILFieldInfoAccessible cenv.g cenv.amap m ad finfo
                           CheckILFieldAttributes cenv.g finfo m
@@ -12081,10 +12084,13 @@ let TcTyconMemberSpecs cenv env containerInfo declKind tpenv (augSpfn: SynMember
 
 let TcModuleOrNamespaceLidAndPermitAutoResolve tcSink env amap (longId : Ident list) =
     let ad = env.eAccessRights
-    let m = longId |> List.map (fun id -> id.idRange) |> List.reduce unionRanges
-    match ResolveLongIndentAsModuleOrNamespace tcSink ResultCollectionSettings.AllResults amap m OpenQualified env.eNameResEnv ad longId true with 
-    | Result res -> Result res
-    | Exception err ->  raze err
+    match longId with
+    | [] -> Result []
+    | id::rest ->
+        let m = longId |> List.map (fun id -> id.idRange) |> List.reduce unionRanges
+        match ResolveLongIndentAsModuleOrNamespace tcSink ResultCollectionSettings.AllResults amap m true OpenQualified env.eNameResEnv ad id rest true with 
+        | Result res -> Result res
+        | Exception err -> raze err
 
 let TcOpenDecl tcSink (g:TcGlobals) amap m scopem env (longId : Ident list)  = 
     let modrefs = ForceRaise (TcModuleOrNamespaceLidAndPermitAutoResolve tcSink env amap longId)
@@ -13581,12 +13587,17 @@ module MutRecBindingChecking =
     /// Check a "module X = A.B.C" module abbreviation declaration
     let TcModuleAbbrevDecl (cenv:cenv) scopem env (id, p, m) = 
         let ad = env.eAccessRights
-        let mvvs = ForceRaise (ResolveLongIndentAsModuleOrNamespace cenv.tcSink ResultCollectionSettings.AllResults cenv.amap m OpenQualified env.eNameResEnv ad p false)
-        let modrefs = mvvs |> List.map p23 
-        if not (List.isEmpty modrefs) && modrefs |> List.forall (fun modref -> modref.IsNamespace) then 
+        let resolved =
+            match p with
+            | [] -> Result []
+            | id::rest -> ResolveLongIndentAsModuleOrNamespace cenv.tcSink ResultCollectionSettings.AllResults cenv.amap m true OpenQualified env.eNameResEnv ad id rest false
+        let mvvs = ForceRaise resolved
+        if isNil mvvs then env else
+        let modrefs = mvvs |> List.map p23
+        if not (isNil modrefs) && modrefs |> List.forall (fun modref -> modref.IsNamespace) then 
             errorR(Error(FSComp.SR.tcModuleAbbreviationForNamespace(fullDisplayTextOfModRef (List.head modrefs)), m))
         let modrefs = modrefs |> List.filter (fun mvv -> not mvv.IsNamespace)
-        if List.isEmpty modrefs then env else 
+        if isNil modrefs then env else 
         modrefs |> List.iter (fun modref -> CheckEntityAttributes cenv.g modref m |> CommitOperationResult)        
         let env = AddModuleAbbreviationAndReport cenv.tcSink scopem id modrefs env
         env
@@ -16364,7 +16375,11 @@ let rec TcSignatureElementNonMutRec cenv parent typeNames endm (env: TcEnv) synS
             
         | SynModuleSigDecl.ModuleAbbrev (id, p, m) -> 
             let ad = env.eAccessRights
-            let mvvs = ForceRaise (ResolveLongIndentAsModuleOrNamespace cenv.tcSink ResultCollectionSettings.AllResults cenv.amap m OpenQualified env.eNameResEnv ad p false)
+            let resolved =
+                match p with
+                | [] -> Result []
+                | id::rest -> ResolveLongIndentAsModuleOrNamespace cenv.tcSink ResultCollectionSettings.AllResults cenv.amap m true OpenQualified env.eNameResEnv ad id rest false
+            let mvvs = ForceRaise resolved
             let scopem = unionRanges m endm
             let unfilteredModrefs = mvvs |> List.map p23
             

src/fsharp/pars.fsy

@@ -3631,6 +3631,13 @@ atomicExprQualification:
   |    identOrOp 
       { let idm = rhs parseState 1 
         (fun e lhsm dotm -> mkSynDot dotm lhsm e $1) }
+
+  | GLOBAL
+      { (fun e lhsm dotm -> 
+            reportParseErrorAt (rhs parseState 3) (FSComp.SR.nrGlobalUsedOnlyAsFirstName()) 
+            let fixedLhsm = mkRange lhsm.FileName lhsm.Start dotm.End // previous lhsm is wrong after 'recover'
+            mkSynDotMissing dotm fixedLhsm e) }
+
   |   /* empty */
       { (fun e lhsm dotm -> 
             reportParseErrorAt dotm (FSComp.SR.parsMissingQualificationAfterDot()) 

tests/fsharpqa/Source/ErrorMessages/NameResolution/E_GlobalQualifierAfterDot.fs

+// #ErrorMessages #NameResolution 
+//<Expects status="error" span="(4,36)" id="FS1126">'global' may only be used as the first name in a qualified path</Expects>
+
+let x = global.System.String.Empty.global.System.String.Empty
+
+exit 0

tests/fsharpqa/Source/ErrorMessages/NameResolution/env.lst

 	SOURCE=E_RecordFieldProposal.fs		# E_RecordFieldProposal
+	SOURCE=E_GlobalQualifierAfterDot.fs		# E_GlobalQualifierAfterDot
 	SOURCE=E_FieldNotInRecord.fs		# E_FieldNotInRecord
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