Add GetApproxTypeHandle dump tests by Copilot · Pull Request #128921 · dotnet/runtime

Copilot · 2026-06-02T22:45:40Z

No description provided.

Co-authored-by: rcj1 <77995559+rcj1@users.noreply.github.com>

dotnet-policy-service · 2026-06-02T22:47:04Z

Tagging subscribers to this area: @steveisok, @tommcdon, @dotnet/dotnet-diag
See info in area-owners.md if you want to be subscribed.

…y+metadataToken Co-authored-by: rcj1 <77995559+rcj1@users.noreply.github.com>

Copilot

Pull request overview

This PR adds dump-based coverage for DacDbiImpl.GetApproxTypeHandle by mirroring the existing exact-type-handle dump tests: it enumerates heap objects reachable from GC handles in the ExactTypeHandle debuggee, constructs the flattened DebuggerIPCE_TypeArgData[] tree (a managed port of CordbType::GatherTypeData), round-trips that through GetApproxTypeHandle, and asserts the returned vmTypeHandle matches an independently canonicalized expected MethodTable. To support this, it also adds a managed TypeDataWalk implementation and refactors some type lookup logic into a helper.

Changes:

Add a new dump test suite DacDbiApproxTypeHandleDumpTests implementing the right-side “gather type data” flattening and expected-handle canonicalization.
Implement managed GetApproxTypeHandle support via a new TypeDataWalk port and supporting helper types.
Replace IsObjRef(TypeHandle) usage with a new IsCorElementTypeObjRef(CorElementType) helper across tests, the contract, and documentation.

Show a summary per file

File	Description
src/native/managed/cdac/tests/MethodTableTests.cs	Updates objref classification assertions to use `IsCorElementTypeObjRef(GetInternalCorElementType(...))`.
src/native/managed/cdac/tests/DumpTests/RuntimeTypeSystemDumpTests.cs	Updates dump-based RTS “objref consistency” test to use the new helper.
src/native/managed/cdac/tests/DumpTests/DacDbi/DacDbiObjectDumpTests.cs	Updates reference-type offset logic to use the new helper.
src/native/managed/cdac/tests/DumpTests/DacDbi/DacDbiApproxTypeHandleDumpTests.cs	New dump test covering round-trip behavior for `GetApproxTypeHandle` across reachable handle objects.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/Dbi/TypeDataWalk.cs	New managed port of the native flattened-type-data walker used by `GetApproxTypeHandle`.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/Dbi/IDacDbiInterface.cs	Adds `DebuggerIPCE_TypeArgData` / `TypeInfoList` and tightens `GetApproxTypeHandle` signature to a typed pointer.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/Dbi/DbiHelpers.cs	New helper for resolving typeDef/typeRef MethodTables from an assembly+token via loader lookup tables.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/Dbi/DacDbiImpl.cs	Implements managed `GetApproxTypeHandle` and switches some ref-type checks to `IsCorElementTypeObjRef`.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/RuntimeTypeSystem_1.cs	Replaces `IsObjRef` with `IsCorElementTypeObjRef` implementation used by the contract.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Abstractions/Contracts/IRuntimeTypeSystem.cs	Changes the contract surface by removing `IsObjRef(TypeHandle)` and adding `IsCorElementTypeObjRef(CorElementType)`.
docs/design/datacontracts/RuntimeTypeSystem.md	Updates contract documentation to match the new helper.

Copilot's findings

Files reviewed: 11/11 changed files
Comments generated: 5

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Copilot

Copilot's findings

Files reviewed: 11/11 changed files
Comments generated: 7

+[StructLayout(LayoutKind.Sequential, Size = 48)]
+public struct DebuggerIPCE_TypeArgData
+{
+    public DebuggerIPCE_ExpandedTypeData data;
+    public uint numTypeArgs; // Portable<UINT>


+[StructLayout(LayoutKind.Sequential)]
+public unsafe struct TypeInfoList
+{
+    public DebuggerIPCE_TypeArgData* m_pList;
+    public int m_nEntries;


+        Assert.True(rts.IsCorElementTypeObjRef(rts.GetInternalCorElementType(objectHandle)));
+        Assert.True(rts.IsCorElementTypeObjRef(rts.GetInternalCorElementType(stringHandle)));
+        Assert.True(rts.IsCorElementTypeObjRef(rts.GetInternalCorElementType(objectArrayHandle)));
+        Assert.False(rts.IsCorElementTypeObjRef(rts.GetInternalCorElementType(intPtrHandle)));


+        Assert.True(contract.IsCorElementTypeObjRef(contract.GetInternalCorElementType(contract.GetTypeHandle(objectTypePtr))));
+        Assert.True(contract.IsCorElementTypeObjRef(contract.GetInternalCorElementType(contract.GetTypeHandle(stringTypePtr))));
+        Assert.True(contract.IsCorElementTypeObjRef(contract.GetInternalCorElementType(contract.GetTypeHandle(szArrayTypePtr))));
+        Assert.False(contract.IsCorElementTypeObjRef(contract.GetInternalCorElementType(contract.GetTypeHandle(truePrimitiveTypePtr))));


Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Copilot

Copilot's findings

Files reviewed: 11/11 changed files
Comments generated: 4

+            case CorElementType.Array:
+            case CorElementType.SzArray:
+            case CorElementType.Ptr:
+            case CorElementType.Byref:
+                pSelf->numTypeArgs = 1;
+                FillTypeNodes(dbi, rts, rts.GetTypeParam(th), nodes, ref idx);
+                break;
+
+            case CorElementType.Class:
+            case CorElementType.ValueType:
+                {
+                    ReadOnlySpan<TypeHandle> inst = rts.GetInstantiation(th);
+                    pSelf->numTypeArgs = (uint)inst.Length;
+                    for (int i = 0; i < inst.Length; i++)
+                        FillTypeNodes(dbi, rts, inst[i], nodes, ref idx);
+                    break;
+                }


    bool IsObject(TypeHandle typeHandle) => throw new NotImplementedException();
    bool IsString(TypeHandle typeHandle) => throw new NotImplementedException();
-    bool IsObjRef(TypeHandle typeHandle) => throw new NotImplementedException();
+    // True if the CorElementType represents a GC-collectable object reference.
+    bool IsCorElementTypeObjRef(CorElementType elementType) => throw new NotImplementedException();
    // True if the MethodTable represents a type that contains managed references


+        Assert.True(rts.IsCorElementTypeObjRef(rts.GetInternalCorElementType(objectHandle)));
+        Assert.True(rts.IsCorElementTypeObjRef(rts.GetInternalCorElementType(stringHandle)));
+        Assert.True(rts.IsCorElementTypeObjRef(rts.GetInternalCorElementType(objectArrayHandle)));
+        Assert.False(rts.IsCorElementTypeObjRef(rts.GetInternalCorElementType(intPtrHandle)));


Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Copilot

Copilot's findings

Files reviewed: 11/11 changed files
Comments generated: 2

+    // True if the CorElementType represents a GC-collectable object reference.
+    bool IsCorElementTypeObjRef(CorElementType elementType) => throw new NotImplementedException();
    // True if the MethodTable represents a type that contains managed references


+        CorElementType et = GetElementType(rts, th);
+        switch (et)
+        {
+            case CorElementType.Array:
+            case CorElementType.SzArray:
+            case CorElementType.Ptr:
+            case CorElementType.Byref:
+                pSelf->numTypeArgs = 1;
+                FillTypeNodes(dbi, rts, rts.GetTypeParam(th), nodes, ref idx);
+                break;
+
+            case CorElementType.Class:
+            case CorElementType.ValueType:
+                {
+                    ReadOnlySpan<TypeHandle> inst = rts.GetInstantiation(th);
+                    pSelf->numTypeArgs = (uint)inst.Length;
+                    for (int i = 0; i < inst.Length; i++)
+                        FillTypeNodes(dbi, rts, inst[i], nodes, ref idx);
+                    break;
+                }
+
+            default:
+                pSelf->numTypeArgs = 0;
+                break;
+        }


Copilot AI and others added 2 commits June 2, 2026 15:30

Implement DacDbiImpl.GetApproxTypeHandle in cDAC

9e0b5cd

Co-authored-by: rcj1 <77995559+rcj1@users.noreply.github.com>

Add DacDbiApproxTypeHandle dump tests

2b5aa4f

Co-authored-by: rcj1 <77995559+rcj1@users.noreply.github.com>

Copilot AI assigned Copilot and rcj1 Jun 2, 2026

Copilot AI requested review from Copilot and removed request for Copilot June 2, 2026 22:45

Copilot created this pull request from a session on behalf of rcj1 June 2, 2026 22:45 View session

github-actions Bot added the area-Diagnostics-coreclr label Jun 2, 2026

Copilot started work on behalf of rcj1 June 3, 2026 00:24 View session

Fix InstantiationApprox to look up open generic typeDef via vmAssembl…

b86eea6

…y+metadataToken Co-authored-by: rcj1 <77995559+rcj1@users.noreply.github.com>

Copilot AI requested review from Copilot and removed request for Copilot June 3, 2026 00:35

Copilot AI changed the title ~~Add DacDbi approximate type handle dump tests~~ Add GetApproxTypeHandle dump tests Jun 3, 2026

Copilot finished work on behalf of rcj1 June 3, 2026 00:35

Copilot AI requested a review from rcj1 June 3, 2026 00:35

Update DacDbiApproxTypeHandleDumpTests.cs

bd99ceb

Copilot AI review requested due to automatic review settings June 3, 2026 02:46

Copilot started reviewing on behalf of rcj1 June 3, 2026 02:46 View session

Copilot AI reviewed Jun 3, 2026

View reviewed changes

Apply suggestions from code review

2fc978b

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Copilot AI review requested due to automatic review settings June 3, 2026 03:50

Copilot started reviewing on behalf of rcj1 June 3, 2026 03:50 View session

Copilot AI reviewed Jun 3, 2026

View reviewed changes

Apply suggestions from code review

28923d0

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Copilot AI review requested due to automatic review settings June 3, 2026 04:02

Copilot started reviewing on behalf of rcj1 June 3, 2026 04:02 View session

Copilot AI reviewed Jun 3, 2026

View reviewed changes

rcj1 and others added 2 commits June 2, 2026 23:05

Update RuntimeTypeSystem_1.cs

9c85a41

Potential fix for pull request finding

d1fb150

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Copilot AI review requested due to automatic review settings June 3, 2026 06:05

Copilot started reviewing on behalf of rcj1 June 3, 2026 06:06 View session

Copilot AI reviewed Jun 3, 2026

View reviewed changes

This was referenced Jun 3, 2026

slow macOS - "##[error]The job running on agent Azure Pipelines 9 ran longer than the maximum time of 60 minutes." dotnet/dnceng#1883

Open

The Operation will be canceled. The next steps may not contain expected logs. dotnet/dnceng#3008

Open

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Add GetApproxTypeHandle dump tests#128921

Add GetApproxTypeHandle dump tests#128921
Copilot wants to merge 8 commits into
mainfrom
copilot/implement-getapproxtypehandle

Copilot AI commented Jun 2, 2026 •

edited by rcj1

Loading

Uh oh!

dotnet-policy-service Bot commented Jun 2, 2026

Uh oh!

Copilot AI left a comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Uh oh!

Uh oh!

Copilot AI left a comment

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Conversation

Copilot AI commented Jun 2, 2026 • edited by rcj1 Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

dotnet-policy-service Bot commented Jun 2, 2026

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Copilot's findings

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Copilot's findings

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Copilot's findings

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Copilot's findings

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Copilot AI commented Jun 2, 2026 •

edited by rcj1

Loading