Unclear what append vs prepend vs replace do

[meganrogge]

Testing #182970

Unclear what append vs prepend vs replace do 🤔

Running this command and relaunching the terminal yields this env

	context.subscriptions.push(vscode.commands.registerCommand('terminalTest.updateEnvironment', () => {
		const collection = context.environmentVariableCollection;
		collection.replace('FOO', 'REPLACED');
		collection.append('APPENDING', 'appending')
		collection.prepend('PREPENDING', 'prepending');
	}));

i was expecting to see PREPENDING at the beginning of the env or at least before the others and the inverse for APPENDING

[Tyriar]

It's nothing to do with the order of the environment, it's how they are applied to the existing variable's value. I think this is already covered by the jsdocs in the stable API as it's referred to as "an environment variable", not environment. I'm guessing you were only looking at the proposal docs?

vscode/src/vscode-dts/vscode.d.ts

Lines 11267 to 11298 in 44b766d

	/**
	* Replace an environment variable with a value.
	*
	* Note that an extension can only make a single change to any one variable, so this will
	* overwrite any previous calls to replace, append or prepend.
	*
	* @param variable The variable to replace.
	* @param value The value to replace the variable with.
	*/
	replace(variable: string, value: string): void;
	/**
	* Append a value to an environment variable.
	*
	* Note that an extension can only make a single change to any one variable, so this will
	* overwrite any previous calls to replace, append or prepend.
	*
	* @param variable The variable to append to.
	* @param value The value to append to the variable.
	*/
	append(variable: string, value: string): void;
	/**
	* Prepend a value to an environment variable.
	*
	* Note that an extension can only make a single change to any one variable, so this will
	* overwrite any previous calls to replace, append or prepend.
	*
	* @param variable The variable to prepend.
	* @param value The value to prepend to the variable.
	*/
	prepend(variable: string, value: string): void;