Merge branch 'main' into ber,a/fixLetBangTree

Author: DedSec256

docs/release-notes/.FSharp.Compiler.Service/11.0.0.md

@@ -2,8 +2,10 @@
 
 * Scripts: Fix resolving the dotnet host path when an SDK directory is specified. ([PR #18960](https://github.com/dotnet/fsharp/pull/18960))
 * Fix excessive StackGuard thread jumping ([PR #18971](https://github.com/dotnet/fsharp/pull/18971))
+* Checking: Fix checking nested fields for records and anonymous ([PR #18964](https://github.com/dotnet/fsharp/pull/18964))
 * Fix name is bound multiple times is not reported in 'as' pattern ([PR #18984](https://github.com/dotnet/fsharp/pull/18984))
 * Syntax Tree: fix return type info for let! / and! / use! ([PR #19004](https://github.com/dotnet/fsharp/pull/19004))
+* Type relations cache: handle potentially "infinite" types ([PR #19010](https://github.com/dotnet/fsharp/pull/19010))
 
 ### Added
 

eng/Version.Details.props

@@ -6,10 +6,10 @@ This file should be imported by eng/Versions.props
 <Project>
   <PropertyGroup>
     <!-- dotnet/msbuild dependencies -->
-    <MicrosoftBuildPackageVersion>18.1.0-preview-25514-02</MicrosoftBuildPackageVersion>
-    <MicrosoftBuildFrameworkPackageVersion>18.1.0-preview-25514-02</MicrosoftBuildFrameworkPackageVersion>
-    <MicrosoftBuildTasksCorePackageVersion>18.1.0-preview-25514-02</MicrosoftBuildTasksCorePackageVersion>
-    <MicrosoftBuildUtilitiesCorePackageVersion>18.1.0-preview-25514-02</MicrosoftBuildUtilitiesCorePackageVersion>
+    <MicrosoftBuildPackageVersion>18.1.0-preview-25515-01</MicrosoftBuildPackageVersion>
+    <MicrosoftBuildFrameworkPackageVersion>18.1.0-preview-25515-01</MicrosoftBuildFrameworkPackageVersion>
+    <MicrosoftBuildTasksCorePackageVersion>18.1.0-preview-25515-01</MicrosoftBuildTasksCorePackageVersion>
+    <MicrosoftBuildUtilitiesCorePackageVersion>18.1.0-preview-25515-01</MicrosoftBuildUtilitiesCorePackageVersion>
     <!-- dotnet/runtime dependencies -->
     <SystemCollectionsImmutablePackageVersion>9.0.0</SystemCollectionsImmutablePackageVersion>
     <SystemComponentModelCompositionPackageVersion>9.0.0</SystemComponentModelCompositionPackageVersion>

eng/Version.Details.xml

@@ -2,21 +2,21 @@
 <Dependencies>
   <Source Uri="https://github.com/dotnet/dotnet" Mapping="fsharp" Sha="01abb3ec5c4cbffec5b33e02156bd3d2a8913b04" BarId="286825" />
   <ProductDependencies>
-    <Dependency Name="Microsoft.Build" Version="18.1.0-preview-25514-02">
+    <Dependency Name="Microsoft.Build" Version="18.1.0-preview-25515-01">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>ce41c053ea92f0f9cf5f68d44015490ec30edfa6</Sha>
+      <Sha>5e273ccd45ba73d9db9b34fceaf9a110412e64e8</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Build.Framework" Version="18.1.0-preview-25514-02">
+    <Dependency Name="Microsoft.Build.Framework" Version="18.1.0-preview-25515-01">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>ce41c053ea92f0f9cf5f68d44015490ec30edfa6</Sha>
+      <Sha>5e273ccd45ba73d9db9b34fceaf9a110412e64e8</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Build.Tasks.Core" Version="18.1.0-preview-25514-02">
+    <Dependency Name="Microsoft.Build.Tasks.Core" Version="18.1.0-preview-25515-01">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>ce41c053ea92f0f9cf5f68d44015490ec30edfa6</Sha>
+      <Sha>5e273ccd45ba73d9db9b34fceaf9a110412e64e8</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Build.Utilities.Core" Version="18.1.0-preview-25514-02">
+    <Dependency Name="Microsoft.Build.Utilities.Core" Version="18.1.0-preview-25515-01">
       <Uri>https://github.com/dotnet/msbuild</Uri>
-      <Sha>ce41c053ea92f0f9cf5f68d44015490ec30edfa6</Sha>
+      <Sha>5e273ccd45ba73d9db9b34fceaf9a110412e64e8</Sha>
     </Dependency>
     <Dependency Name="System.Reflection.Metadata" Version="9.0.0">
       <Uri>https://github.com/dotnet/runtime</Uri>

eng/Versions.props

@@ -46,7 +46,7 @@
     <FSharpCorePreviewPackageVersionValue>$(FSCorePackageVersionValue)-$(PreReleaseVersionLabel).*</FSharpCorePreviewPackageVersionValue>
     <!-- -->
     <!-- FSharp tools for Visual Studio version number -->
-    <FSToolsMajorVersion>14</FSToolsMajorVersion>
+    <FSToolsMajorVersion>15</FSToolsMajorVersion>
     <FSToolsMinorVersion>0</FSToolsMinorVersion>
     <FSToolsBuildVersion>$(FSBuildVersion)</FSToolsBuildVersion>
     <FSToolsRevisionVersion>$(FSRevisionVersion)</FSToolsRevisionVersion>

src/Compiler/Checking/CheckRecordSyntaxHelpers.fs

@@ -156,12 +156,26 @@ let TransformAstForNestedUpdates (cenv: TcFileState) (env: TcEnv) overallTy (lid
         (accessIds, outerFieldId),
         Some(synExprRecd (recdExprCopyInfo (fields |> List.map fst) withExpr) outerFieldId rest exprBeingAssigned)
 
+/// This name is used when a complex expression is bound for use as a binding in a copy-and-update expression.
+/// For example, in `{ f () with ... }`, `f ()` is replaced by `let bind@ = f ()`
+let BindIdText = "bind@"
+
+/// Finding the 'bind@' identifier is the only way to detect that an expression has already been bound.
+let inline (|IsSimpleOrBoundExpr|_|) (withExprOpt: (SynExpr * BlockSeparator) option) =
+    match withExprOpt with
+    | None -> true
+    | Some(expr, _) ->
+        match expr with
+        | SynExpr.LongIdent(_, lIds, _, _) -> lIds.LongIdent |> List.exists (fun id -> id.idText = BindIdText)
+        | SynExpr.Ident _ -> true
+        | _ -> false
+
 /// When the original expression in copy-and-update is more complex than `{ x with ... }`, like `{ f () with ... }`,
 /// we bind it first, so that it's not evaluated multiple times during a nested update
 let BindOriginalRecdExpr (withExpr: SynExpr * BlockSeparator) mkRecdExpr =
     let originalExpr, blockSep = withExpr
     let mOrigExprSynth = originalExpr.Range.MakeSynthetic()
-    let id = mkSynId mOrigExprSynth "bind@"
+    let id = mkSynId mOrigExprSynth BindIdText
     let withExpr = SynExpr.Ident id, blockSep
 
     let binding =

src/Compiler/Checking/CheckRecordSyntaxHelpers.fsi

@@ -19,5 +19,9 @@ val TransformAstForNestedUpdates<'a> :
     withExpr: SynExpr * (range * 'a) ->
         (Ident list * Ident) * SynExpr option
 
+val BindIdText: string
+
+val inline (|IsSimpleOrBoundExpr|_|): withExprOpt: (SynExpr * BlockSeparator) option -> bool
+
 val BindOriginalRecdExpr:
     withExpr: SynExpr * BlockSeparator -> mkRecdExpr: ((SynExpr * BlockSeparator) option -> SynExpr) -> SynExpr

src/Compiler/Checking/Expressions/CheckExpressions.fs

@@ -5895,9 +5895,8 @@ and TcExprUndelayed (cenv: cenv) (overallTy: OverallTy) env tpenv (synExpr: SynE
         TcExprTuple cenv overallTy env tpenv (isExplicitStruct, args, m)
 
     | SynExpr.AnonRecd (isStruct, withExprOpt, unsortedFieldExprs, mWholeExpr, trivia) ->
-        match withExprOpt with
-        | None
-        | Some(SynExpr.Ident _, _) ->
+        match withExprOpt with 
+        | None | IsSimpleOrBoundExpr ->
             TcNonControlFlowExpr env <| fun env ->
             TcPossiblyPropagatingExprLeafThenConvert (fun ty -> isAnonRecdTy g ty || isTyparTy g ty) cenv overallTy env mWholeExpr (fun overallTy ->
                 TcAnonRecdExpr cenv overallTy env tpenv (isStruct, withExprOpt, unsortedFieldExprs, mWholeExpr)
@@ -5929,10 +5928,9 @@ and TcExprUndelayed (cenv: cenv) (overallTy: OverallTy) env tpenv (synExpr: SynE
         let binds = unionBindingAndMembers binds members
         TcExprObjectExpr cenv overallTy env tpenv (synObjTy, argopt, binds, extraImpls, mNewExpr, m)
 
-    | SynExpr.Record (inherits, withExprOpt, synRecdFields, mWholeExpr) ->
+    | SynExpr.Record (inherits, withExprOpt, synRecdFields, mWholeExpr) ->        
         match withExprOpt with
-        | None
-        | Some(SynExpr.Ident _, _) ->
+        | None | IsSimpleOrBoundExpr ->
             TcNonControlFlowExpr env <| fun env ->
             TcExprRecord cenv overallTy env tpenv (inherits, withExprOpt, synRecdFields, mWholeExpr)
         | Some withExpr ->

src/Compiler/Checking/TypeRelations.fs

@@ -28,8 +28,12 @@ type CanCoerce =
 [<Struct; NoComparison>]
 type TTypeCacheKey =
     | TTypeCacheKey of TypeStructure * TypeStructure * CanCoerce
-    static member FromStrippedTypes(ty1, ty2, canCoerce) =
-        TTypeCacheKey(getTypeStructure ty1, getTypeStructure ty2, canCoerce)
+    static member TryGetFromStrippedTypes(ty1, ty2, canCoerce) =
+        let t1, t2 = getTypeStructure ty1, getTypeStructure ty2
+        if t1.IsPossiblyInfinite || t2.IsPossiblyInfinite then
+            ValueNone
+        else
+            ValueSome (TTypeCacheKey(t1, t2, canCoerce))
 
 let getTypeSubsumptionCache =
     let factory (g: TcGlobals) =
@@ -157,8 +161,10 @@ let rec TypeFeasiblySubsumesType ndeep (g: TcGlobals) (amap: ImportMap) m (ty1:
                     List.exists (TypeFeasiblySubsumesType (ndeep + 1) g amap m ty1 NoCoerce) interfaces
 
     if g.langVersion.SupportsFeature LanguageFeature.UseTypeSubsumptionCache then
-        let key = TTypeCacheKey.FromStrippedTypes(ty1, ty2, canCoerce)
-        (getTypeSubsumptionCache g).GetOrAdd(key, fun _ -> checkSubsumes ty1 ty2)
+        match TTypeCacheKey.TryGetFromStrippedTypes(ty1, ty2, canCoerce) with
+        | ValueSome key ->
+            (getTypeSubsumptionCache g).GetOrAdd(key, fun _ -> checkSubsumes ty1 ty2)
+        | _ -> checkSubsumes ty1 ty2
     else
         checkSubsumes ty1 ty2
 

src/Compiler/Utilities/TypeHashing.fs

@@ -401,7 +401,9 @@ module StructuralUtilities =
         | MeasureRational of int * int
         | NeverEqual of never: NeverEqual
 
-    type TypeStructure = TypeStructure of ImmutableArray<TypeToken>
+    type TypeStructure =
+        | TypeStructure of TypeToken[]
+        | PossiblyInfinite of never: NeverEqual
 
     let inline toNullnessToken (n: Nullness) =
         match n.TryEvaluate() with
@@ -464,6 +466,15 @@ module StructuralUtilities =
             | TType_measure m -> yield! accumulateMeasure m
         }
 
+    // If the sequence got too long, just drop it, we could be dealing with an infinite type.
+    let private toTypeStructure tokens =
+        let tokens = tokens |> Seq.truncate 256 |> Array.ofSeq
+
+        if tokens.Length = 256 then
+            PossiblyInfinite NeverEqual.Singleton
+        else
+            TypeStructure tokens
+
     /// Get the full structure of a type as a sequence of tokens, suitable for equality
     let getTypeStructure =
-        Extras.WeakMap.getOrCreate (fun ty -> accumulateTType ty |> ImmutableArray.ofSeq |> TypeStructure)
+        Extras.WeakMap.getOrCreate (fun ty -> accumulateTType ty |> toTypeStructure)

tests/FSharp.Compiler.ComponentTests/Language/CopyAndUpdateTests.fs

@@ -480,3 +480,56 @@ if actual <> expected then
     |> withLangVersion80
     |> compileExeAndRun
     |> verifyOutput "once"
+
+[<Fact>]
+let ``N-Nested copy-and-update works when the starting expression is not a simple identifier``() =
+    FSharp """
+module CopyAndUpdateTests
+type SubSubTest = {
+    Z: int
+}
+
+type SubTest = {
+    Y: SubSubTest
+}
+
+type Test = {
+    X: SubTest
+}
+
+let getTest () =
+    { X = { Y = { Z = 0 } } }
+
+[<EntryPoint>]
+let main argv =
+    let a = {
+         getTest () with
+            X.Y.Z = 1 
+    }
+    printfn "%i" a.X.Y.Z |> ignore
+    0
+    """
+    |> typecheck
+    |> shouldSucceed
+    |> verifyOutput "1"
+
+[<Fact>]
+let ``N-Nested, anonymous copy-and-update works when the starting expression is not a simple identifier``() =
+    FSharp """
+module CopyAndUpdateTests
+
+let getTest () =
+    {| X = {| Y = {| Z = 0 |} |} |}
+
+[<EntryPoint>]
+let main argv =
+    let a = {|
+         getTest () with
+            X.Y.Z = 1 
+    |}
+    printfn "%i" a.X.Y.Z |> ignore
+    0
+    """
+    |> typecheck
+    |> shouldSucceed
+    |> verifyOutput "1"