WebAssembly hot reload reverts to old version of a type

[SteveSandersonMS]

Description

It's possible this is a known limitation and that @lambdageek has it on a backlog, but @pranavkm said I should report things to ensure they are tracked.

The WebAssembly hot reload support is amazingly fast (really amazingly - I've never seen hot reload so fast on any other tech) but currently it appears to be limited to making changes in a single type. If you have type A referencing B, and you edit B then the change appears, but if you then edit A, your change to A appears but it reverts to referencing the old unedited version of B.

More precise steps:

• Use latest preview 3 SDK
• dotnet new blazorwasm -o MyApp
• cd MyApp

Issue 1:

• Edit Pages/Index.html, adding <Counter />
• dotnet watch. See your counter on the home screen.
• Edit Pages/Counter.razor, e.g., changing the <h1> element to <h1>Counter2</h1>. See this show up on the home screen where you added it.
• Edit Pages/Index.razor to add a second <Counter />.
  • Expected: New counter appears also with title Counter2
  • Actual: New counter appears, but the title is Counter, and the other counter component also reverts its title to Counter.

Issue 2:

• dotnet watch
• Edit Shared/SurveyPrompt.razor, changing some text (e.g., tell us what you think -> HELLO). See your change appear correctly in the browser window.
• Go to Index.razor and try to edit the <h1> text.
  • Expected: change shows up
  • Actual: Nothing happens

Configuration

This is with SDK 6.0.100-preview.3.21173.6, with Microsoft.NETCoreSdk.BundledVersions.props patched to use the runtime version 6.0.0-preview.4.21174.4.

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Issue Details

---

Description

It's possible this is a known limitation and that @lambdageek has it on a backlog, but @pranavkm said I should report things to ensure they are tracked.

The WebAssembly hot reload support is amazingly fast (really amazingly - I've never seen hot reload so fast on any other tech) but currently it appears to be limited to making changes in a single type. If you have type A referencing B, and you edit B then the change appears, but if you then edit A, your change to A appears but it reverts to referencing the old unedited version of B.

More precise steps:

• Use latest preview 3 SDK
• dotnet new blazorwasm -o MyApp
• cd MyApp

Issue 1:

• Edit Pages/Index.html, adding <Counter />
• dotnet watch. See your counter on the home screen.
• Edit Pages/Counter.razor, e.g., changing the <h1> element to <h1>Counter2</h1>. See this show up on the home screen where you added it.
• Edit Pages/Index.razor to add a second <Counter />.
  • Expected: New counter appears also with title Counter2
  • Actual: New counter appears, but the title is Counter, and the other counter component also reverts its title to Counter.

Issue 2:

• dotnet watch
• Edit Shared/SurveyPrompt.razor, changing some text (e.g., tell us what you think -> HELLO). See your change appear correctly in the browser window.
• Go to Index.razor and try to edit the <h1> text.
  • Expected: change shows up
  • Actual: Nothing happens

Configuration

This is with SDK 6.0.100-preview.3.21173.6, with Microsoft.NETCoreSdk.BundledVersions.props patched to use the runtime version 6.0.0-preview.4.21174.4.

Author:	SteveSandersonMS
Assignees:	-
Labels:	arch-wasm, untriaged
Milestone:	-

Tagging subscribers to this area: @CoffeeFlux
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Description

It's possible this is a known limitation and that @lambdageek has it on a backlog, but @pranavkm said I should report things to ensure they are tracked.

The WebAssembly hot reload support is amazingly fast (really amazingly - I've never seen hot reload so fast on any other tech) but currently it appears to be limited to making changes in a single type. If you have type A referencing B, and you edit B then the change appears, but if you then edit A, your change to A appears but it reverts to referencing the old unedited version of B.

More precise steps:

• Use latest preview 3 SDK
• dotnet new blazorwasm -o MyApp
• cd MyApp

Issue 1:

• Edit Pages/Index.html, adding <Counter />
• dotnet watch. See your counter on the home screen.
• Edit Pages/Counter.razor, e.g., changing the <h1> element to <h1>Counter2</h1>. See this show up on the home screen where you added it.
• Edit Pages/Index.razor to add a second <Counter />.
  • Expected: New counter appears also with title Counter2
  • Actual: New counter appears, but the title is Counter, and the other counter component also reverts its title to Counter.

Issue 2:

• dotnet watch
• Edit Shared/SurveyPrompt.razor, changing some text (e.g., tell us what you think -> HELLO). See your change appear correctly in the browser window.
• Go to Index.razor and try to edit the <h1> text.
  • Expected: change shows up
  • Actual: Nothing happens

Configuration

This is with SDK 6.0.100-preview.3.21173.6, with Microsoft.NETCoreSdk.BundledVersions.props patched to use the runtime version 6.0.0-preview.4.21174.4.

Author:	SteveSandersonMS
Assignees:	lambdageek
Labels:	arch-wasm, area-VM-meta-mono, untriaged
Milestone:	-

[lambdageek]

Can reproduce the issue (both on wasm and console). Investigating why we're picking up the wrong method body.

It's definitely method bodies - it's not just string changes - swapping and ldc.i4.0 for an ldc.i4.1 also doesn't come through.

[lambdageek]

The problem is in get_method_update_rva in the case where there are multiple generations, if the lookup in a later generation returns NULL because that generation didn't update the method definition, we treat that as a valid 0 value and return to the caller who interprets it as "no updates at all" and returns the base method.

tl;dr I fail at writing a lookup function. 😓