Test plan for CheckedUserDefinedOperators feature

[AlekseyTs]

Feature branch - https://github.com/dotnet/roslyn/tree/features/CheckedUserDefinedOperators Specification - https://github.com/dotnet/csharplang/blob/main/proposals/csharp-11.0/checked-user-defined-operators.md Proposal: https://github.com/dotnet/csharplang/issues/4665

Compiler

• [x] LangVer
• [x] sync with F# team
• [x] Confirm VB behavior (operators are ignored)
• [x] Confirm C++/CLI does not crash
• [x] Build VS

Compiler Public APIs

• [x] SyntaxNormalizer
• [x] ClassifyConversion
  • [x] Specified position is a checked context
  • [x] No position specified (should we have an overload for specified whether to treat the conversion as checked?)
• [x] SymbolDisplay

Syntax

• [x] checked on
  • [x] concrete conversion operators
  • [x] abstract conversion operators
    • [x] Definitions
    • [x] Explicit implementations
  • [x] implicit conversion operators (error)
  • [x] explicit conversion operators
  • [x] concrete unary operators
  • [x] abstract unary operators
  • [x] concrete binary operators
  • [x] abstract binary operators
• [x] Misplaced checked
• [x] checked in cref
• [x] graceful recovery on unchecked (issue)

Semantics

• [x] checked expression context calls operator
  • [x] Regular operators
  • [x] Compound assignment operators
• [x] checked method context calls operator
  • [x] Regular operators
  • [x] Compound assignment operators
• [x] -checked compiler switch calls operator
  • [x] Regular operators
  • [x] Compound assignment operators
• [x] Source requires matching unchecked operator
• [x] Paired operators in metadata can differ by everything but parameter/return type
• [x] In unchecked contexts, checked operators are ignored during lookup
  • [x] Binary operators
  • [x] Unary operators
  • [x] Conversion operators
• [x] In checked contexts, unchecked operators (regular operators that have a paired checked operator) are ignored during lookup
  • [x] Binary operators
  • [x] Unary operators
  • [x] Conversion operators
• [x] In checked contexts, regular operators that are not unchecked are included during lookup
  • [x] Binary operators
  • [x] Unary operators
  • [x] Conversion operators
• [x] Lifted conversion chooses checked conversions in checked contexts
• [x] DLR behavior
• [x] Expression trees contain new operator types
  • [x] Binary operators
  • [x] Unary operators
  • [x] Conversion operators
• [x] Obsolete
  • [x] Binary operators
  • [x] Unary operators
  • [x] Conversion operators

Productivity

• [x] Declaring checked operators
• [x] Using operators in expressions
• [x] QuickInfo should show whether a checked or regular operator is used
  • [x] User-defined operators
  • [x] Intrinsic operators
• [x] checked keyword classification
• [x] Syntax normalizer for declarations
• [x] checked keyword completion https://github.com/dotnet/roslyn/pull/60183
• [x] Go to definition from operator usage and explicit interface implementation
• [x] Find all references for checked operators - doesn't work #60216
• [x] Go To Implementation
• [x] Operator completion for explicit implementation - doesn't work #60215
• [x] Implement interface fixer - doesn't work #60214
• [x] F1 on checked keyword on the declaration goes to the doc page for checked keyword.
• [x] Formatter tests https://github.com/dotnet/roslyn/pull/60375
  • [x] Signature formatting
  • [x] Indentation inside operator
• [x] Navbar - https://github.com/dotnet/roslyn/pull/60727/
• [x] Object Browser - https://github.com/dotnet/roslyn/pull/60727/
• [x] Metadata as source - https://github.com/dotnet/roslyn/pull/60727/

Docs

• [x] We might need to adjust F1 behavior on checked keyword in declarations, depending on structure of the docs. Right now it goes to a general checked keyword topic.

[333fred]

I've added more to the test plan. I'll go through and check things off on Monday.

[Rekkonnect]

Just tried the feature out, and I think it would be nice to have a more specific error when a user types:

public static int operator unchecked +(int left, int right);
//                         ~~~~~~~~~

Saying that unchecked operators do not require the modifier. Currently, multiple unrelated errors are being shown:

[AlekseyTs]

@AlFasGD This issue is not meant for tracking and discussing different aspects of the feature. If you would like to report a bug or suggestion, please, open a dedicated issue.