collection applied twice for second terminal

[meganrogge]

Testing #182970

In my extension's activate function, I have:

vscode.window.createTerminal({
	name: `Ext Terminal tranisent #${NEXT_TERM_ID++}`,
	isTransient: true
} as any);
vscode.window.createTerminal({
	name: `Ext Terminal tranisent #${NEXT_TERM_ID++}`,
	isTransient: true,
	shellPath: 'fish'
} as any);
const collection = context.environmentVariableCollection;
collection.replace('FOO', 'REPLACED', { applyAtShellIntegration: true });
collection.append('APPENDING', 'appending', { applyAtShellIntegration: true })
collection.prepend('PREPENDING', 'prepending', { applyAtShellIntegration: true });

When the extension activates, I log the env in each terminal. In the first, zsh, the mutations are applied right next to each-other in order

In the second, fish, I see that they're applied in a different order and the appending / prepending happens twice. I'm not sure if this is expected.

[Tyriar]

This is probably expected because different shells do different things on startup. To be sure, set apply at process creation to false

[meganrogge]

does not occur when I set process creation to false

[Tyriar]

Will bring up in API sync #179476 (comment)