[vscode] Add iconPath and stub color optional properties to TerminalOptions and ExtensionTerminalOptions

[rschnekenbu]

What it does

Add iconPath optional property to TerminalOptions and ExtensionTerminalOptions
Stub color optional property to TerminalOptions and ExtensionTerminalOptions
This allows creation of terminals from extension with different icons.

Fixes #11504

Contributed on behalf of STMicroelectronics

How to test

1. Install extension terminal-creation-options-0.0.13.zip
   . This extension provides several actions to open a new terminal with a different icon in the title and several color options (not supported yet)
2. Trigger in the command Palette different commands:

• 'Create terminal with green Theme Icon'. a new terminal with a file icon shall open.
• 'Create terminal with red URI Icon'. A terminal with default terminal icon shall open as the URIs iconPath is not yet supported.
• 'Create new terminal' should create a terminal with standard terminal icon.

Known limitations

1. Color is not supported but stubbed, so the extension is still supported. The support is strange in vscode, as having a specific color changes also the icon to a kind of cube (at least when I am testing). The main technical reason is that underlying representation Title, coming from phosphorjs library, does not directly support styling. The phosphorjs library is deprecated now, so this may be hard to have a proper fix.
2. Only ThemeIcon is supported currently in iconPath. URI(s) based icons are not supported, but extension does not fail. Same reason for the color management applies here. The limitation comes from Title only accepting iconClass string. I have seen some similar work on webview title, but this includes some dependencies to classes in plugin-ext package (PluginSharedStyle, and some other elements). In Terminal-Widget-impl, we are in terminal package. Terminal package can not depend on plugin-ext as it would introduce circular dependencies. So there maybe some other way to implement, but with either some code duplication or a larger refactoring required. This will be part of a following issue once this PR is merged.

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines

[vince-fugnitto]

@rschnekenbu the APIs added are already optional and shouldn't affect the extension from loading or starting. Given that, why should we stub and not just implement the API properly when ready?

[rschnekenbu]

@vince-fugnitto, I think this PR still makes sense for 2 points: the support for the icon is already be partially availlable for the incoming release and the API is clearly marked as stubbed, not simply ignored. Second point would mean we could step up the vscode API compatibility version with some remaining work clearly tracked.
Thanks in any case to have commented this PR!

[vince-fugnitto]

@rschnekenbu If we want to stub I'm mainly wondering if we should instead mark both iconPath and color as stubbed given they are implemented partially or not at alll. Currently we have (compatibility report with this branch):

It is misleading to mark iconPath as fully compatible, perhaps partial or stubbed is more representative. The color property for ExtensionTerminalOptions should be marked as stubbed as well.

[rschnekenbu]

@vince-fugnitto, indeed, that can be misleading for iconPath. I updated the contribution removing the URIs on iconPath.
I also added 'stubbed' marker to ExtensionTerminalOptions.color.

Here is the report on TerminalOptions and ExtensionTerminalOptions now:

[vince-fugnitto]

LGTM 👍 I think it's better now that we represent the actual support, and we can track compatibility.