Investigate flaky unit tests failing intermittently after vscode source refresh

[kburtram]

There are a handful of unit tests failing intermittently in the canary builds that need to be investigated. I'll use this issue to keep a list of these tests and provide status on fixing, disabling, etc.

Initial list of tests to investigate:

TerminalLinkManager
    getLinks and open recent link
      ✔ should return web links in order
      1) should return web links in order

DefaultConfiguration
    ✔ configuration default overrides are read from environment
    1) configuration default overrides are read from environment

Getting Started Markdown Renderer
    ✔ renders theme picker markdown with images
    1) renders theme picker markdown with images

A couple other ones...
1) Buffer Content Tracker
       should cap the size of the cached lines, removing old lines in favor of new lines:

 2) Buffer Content Tracker
       should cap the size of the cached lines, removing old lines in favor of new lines:

[kburtram]

I've tried to disable the suites I'm seeing failing in the canary builds to understand if this xterm issue is isolated to a handful suites, and to try to stabilize the canary & PR builds. #23535. This doesn't seem like a good long-term fix so will continue to investigate after looking at some other issues.

[kburtram]

This PR disables an additional suite for the same issue #23539.

[kburtram]

This is one more suite impacted by this issue #23545.

[kburtram]

One more test suite #23550.

[kburtram]

One more #23557

[kburtram]

The xterm glyph issue keeps popping up during other suites, so I'm going to stop disabling them. Though I will keep the above mentioned one disabled while investigating the builds are significantly more stable w/o them.

[kburtram]

Additional suites that failed in canary yesterday #23589

[SakshiS-harma]

A few more tests with similar error:

• PreferencesService
  ✔ options are preserved when calling openEditor

  1. options are preserved when calling openEditor
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• CredentialsService - web
  ✔ Gets null for no service or a different service

  1. Gets null for no service or a different service
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• CredentialsService - web
  ✔ Delete removes the value

  1. Delete removes the value
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• CredentialsService - web
  ✔ Gets correct value for credential

  1. Gets correct value for credential
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ errors cases - parse errors

  1. errors cases - parse errors
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ remove a user keybinding

  1. remove a user keybinding
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ errors cases - did not find an array

  1. errors cases - did not find an array
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ edit a default keybinding to an empty array

  1. edit a default keybinding to an empty array
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ errors cases - dirty

  1. errors cases - dirty
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ add a new default keybinding

  1. add a new default keybinding
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ add a new keybinding to unassigned keybinding

  1. add a new keybinding to unassigned keybinding
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ edit an user keybinding

  1. edit an user keybinding
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')
     KeybindingsEditing
     ✔ remove a default keybinding
  2. remove a default keybinding
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ add a new default keybinding using edit

  1. add a new default keybinding using edit
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ edit a default keybinding to an empty file

  1. edit a default keybinding to an empty file
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ edit a default keybinding in an existing array

  1. edit a default keybinding in an existing array
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ errors cases - dirty

  1. errors cases - dirty
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ add another keybinding

  1. add another keybinding
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ remove a user keybinding

  1. remove a user keybinding
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• KeybindingsEditing
  ✔ reset an edited keybinding

  1. reset an edited keybinding
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• Workbench - TerminalInstance
  TerminalLabelComputer
  ✔ should resolve to "" when the template variables are empty
  1) should resolve to "" when the template variables are empty
  Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• FileDialogService
  ✔ Remote - open/save workspaces availableFilesystems

  1. Remote - open/save workspaces availableFilesystems
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• FileDialogService
  ✔ Virtual - open/save workspaces availableFilesystems

  1. Virtual - open/save workspaces availableFilesystems
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• FileDialogService
  ✔ Local - open/save workspaces availableFilesystems

  1. Local - open/save workspaces availableFilesystems
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• ExtensionStorageMigration
  ✔ migrate extension storage when does not exist

  1. migrate extension storage when does not exist
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

• ExtensionStorageMigration
  ✔ migrate extension storage

  1. migrate extension storage
     Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph')

[Charles-Gagnon]

I chatted with Daniel from the VS Code team (owns the xterm stuff there) and his suggestion for a temporary fix would be to set up the tests to use the DOM renderer instead like they do for their smoke tests : https://github.com/microsoft/vscode/blob/0c3fb42a1e31f63ec7f17906a19bbcebdbe8bb3e/test/smoke/src/areas/terminal/terminal-helpers.ts#L15-L17

I'll try to send out for a PR for that this week, but if anyone else had time feel free to take this up 😄

[kisantia]

There have still been test failures in the canary builds after #23770 was merged. @lewis-sanchez can you please take another look and disable these if needed?
Tests:

• Buffer Content Tracker should cap the size of the cached lines, removing old lines in favor of new lines
  Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph') (/__w/1/s/node_modules/xterm-addon-canvas/lib/xterm-addon-canvas.js:1)
• Buffer Content Tracker should refresh viewport with full scrollback
  Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph') (/__w/1/s/node_modules/xterm-addon-canvas/lib/xterm-addon-canvas.js:1)
• DefaultConfiguration configuration default overrides are read from cache
  Error: Uncaught TypeError: Cannot read properties of undefined (reading 'getRasterizedGlyph') (/__w/1/s/node_modules/xterm-addon-canvas/lib/xterm-addon-canvas.js:1)

[Charles-Gagnon]

Before disabling, please see if these tests are using the config that you added in the previous PR. If that test config service isn't actually used by every test by default then we may need to find another solution to ensure that every test picks up the config.

If it is being used then we should probably revert the change - since it doesn't seem to actually solve the problem - and investigate other options (such as fixing xterm itself).