Better anonymous record error reporting

src/Compiler/Checking/NameResolution.fs

@@ -3685,8 +3685,9 @@ let ResolveFieldPrim sink (ncenv: NameResolver) nenv ad ty (mp, id: Ident) allFi
     | [] ->
         let lookup() =
             let frefs =
-                try Map.find id.idText nenv.eFieldLabels
-                with :? KeyNotFoundException ->
+                match Map.tryFind id.idText nenv.eFieldLabels with
+                | Some fields -> fields
+                | None ->
                     // record label is unknown -> suggest related labels and give a hint to the user
                     error(SuggestLabelsOfRelatedRecords g nenv id allFields)
 
@@ -3716,8 +3717,7 @@ let ResolveFieldPrim sink (ncenv: NameResolver) nenv ad ty (mp, id: Ident) allFi
                     error(ErrorWithSuggestions(errorText, m, id.idText, suggestLabels))
                 else
                     lookup()
-        | _ ->
-            lookup()
+        | ValueNone -> lookup()
     | _ ->
         let lid = (mp@[id])
         let tyconSearch ad () =
@@ -3749,16 +3749,26 @@ let ResolveFieldPrim sink (ncenv: NameResolver) nenv ad ty (mp, id: Ident) allFi
             errorR(Error(FSComp.SR.nrInvalidFieldLabel(), (List.head rest).idRange))
 
         [(resInfo, item)]
+
+let ResolveAnonRecField (g: TcGlobals) ty (fldId: Ident) =
+    if (TryFindAnonRecdFieldOfType g ty fldId.idText).IsSome then
+        error(Error(FSComp.SR.chkAnonymousRecordFields(fldId.idText, fldId.idText), fldId.idRange))
+    else
+        error(UndefinedName(0, FSComp.SR.undefinedNameRecordLabel, fldId, NoSuggestions))
 
-let ResolveField sink ncenv nenv ad ty mp id allFields =
-    let res = ResolveFieldPrim sink ncenv nenv ad ty (mp, id) allFields
-    // Register the results of any field paths "Module.Type" in "Module.Type.field" as a name resolution. (Note, the path resolution
-    // info is only non-empty if there was a unique resolution of the field)
-    let checker = ResultTyparChecker(fun () -> true)
-    res
-    |> List.map (fun (resInfo, rfref) ->
-        ResolutionInfo.SendEntityPathToSink(sink, ncenv, nenv, ItemOccurence.UseInType, ad, resInfo, checker)
-        rfref)
+let ResolveField sink (ncenv: NameResolver) nenv ad ty mp id allFields =
+    if isAnonRecdTy ncenv.g ty || isStructAnonRecdTy ncenv.g ty then
+        ResolveAnonRecField ncenv.g ty id
+        []
+    else
+        let res = ResolveFieldPrim sink ncenv nenv ad ty (mp, id) allFields
+        // Register the results of any field paths "Module.Type" in "Module.Type.field" as a name resolution. (Note, the path resolution
+        // info is only non-empty if there was a unique resolution of the field)
+        let checker = ResultTyparChecker(fun () -> true)
+        res
+        |> List.map (fun (resInfo, rfref) ->
+            ResolutionInfo.SendEntityPathToSink(sink, ncenv, nenv, ItemOccurence.UseInType, ad, resInfo, checker)
+            rfref)
 
 /// Resolve a long identifier representing a nested record field.
 ///

src/Compiler/FSComp.txt

@@ -1700,5 +1700,6 @@ featureInformationalObjInferenceDiagnostic,"Diagnostic 3559 (warn when obj infer
 3566,tcMultipleRecdTypeChoice,"Multiple type matches were found:\n%s\nThe type '%s' was used. Due to the overlapping field names\n%s\nconsider using type annotations or change the order of open statements."
 3567,parsMissingMemberBody,"Expecting member body"
 3568,parsMissingKeyword,"Missing keyword '%s'"
-3569,chkNotTailRecursive,"The member or function '%s' has the 'TailCallAttribute' attribute, but is not being used in a tail recursive way."
-3577,tcOverrideUsesMultipleArgumentsInsteadOfTuple,"This override takes a tuple instead of multiple arguments. Try to add an additional layer of parentheses at the method definition (e.g. 'member _.Foo((x, y))'), or remove parentheses at the abstract method declaration (e.g. 'abstract member Foo: 'a * 'b -> 'c')."
+3577,tcOverrideUsesMultipleArgumentsInsteadOfTuple,"This override takes a tuple instead of multiple arguments. Try to add an additional layer of parentheses at the method definition (e.g. 'member _.Foo((x, y))'), or remove parentheses at the abstract method declaration (e.g. 'abstract member Foo: 'a * 'b -> 'c')."
+3578,chkAnonymousRecordFields,"Label '%s' is part of anonymous record. Use {{| expr with %s = ... |}} instead."
+3569,chkNotTailRecursive,"The member or function '%s' has the 'TailCallAttribute' attribute, but is not being used in a tail recursive way."

tests/FSharp.Compiler.ComponentTests/Conformance/Types/RecordTypes/AnonymousRecords.fs

@@ -65,7 +65,33 @@ type ErrorResponse =
             Error 10, Line 7, Col 12, Line 7, Col 14, "Unexpected symbol '|}' in field declaration. Expected identifier or other token."
             Error 10, Line 10, Col 17, Line 10, Col 21, "Incomplete structured construct at or before this point in field declaration. Expected identifier or other token."
         ]
+
+    [<Fact>]
+    let ``Anonymous Record type annotation with with fields defined in a record`` () =
+        Fsx """
+type T = { ff : int }
 
+let t3 (t1: {| gu: string; ff: int |}) = { t1 with ff = 3 }
+        """
+        |> ignoreWarnings
+        |> compile
+        |> shouldFail
+        |> withDiagnostics [
+            (Error 3578, Line 4, Col 52, Line 4, Col 54, "Label 'ff' is part of anonymous record. Use {| expr with ff = ... |} instead.")
+        ]
+
+    [<Fact>]
+    let ``This expression was expected to have an anonymous Record but has a record`` () =
+        Fsx """
+let t3 (t1: {| gu: string; ff: int |}) = { t1 with ff = 3 }
+        """
+        |> ignoreWarnings
+        |> compile
+        |> shouldFail
+        |> withDiagnostics [
+            (Error 3578, Line 2, Col 52, Line 2, Col 54, "Label 'ff' is part of anonymous record. Use {| expr with ff = ... |} instead.")
+        ]
+
     [<Fact>]
     let ``Nested anonymous records where outer label = concatenated inner labels (see secondary issue reported in 6411)`` () =
         FSharp """
@@ -74,4 +100,5 @@ module NestedAnonRecds
 let x = {| abcd = {| ab = 4; cd = 1 |} |}
 """
         |> compile
-        |> shouldSucceed
+        |> shouldSucceed
+