TSLint: show a warning when accessing node.js globals in common|browser

[bpasero]

We have lots of TSLint rules today that help us prevent pushing badly layered code. However we fail to detect usage such as process or Buffer in common|browser layer.

I am not an expert in TS and have just thrown together a trivial version that checks on identifier names (in #79222):

I need someone with more expertise to make it smarter (@mjbvz ?). Ideally we can only report a warning if the resolved type is coming from a certain d.ts file (e.g. node.d.ts). Not sure if that is possible.

Implementation:

visitIdentifier(node: ts.Identifier) {
	if (this._config.unsafe.some(unsafe => unsafe === node.text)) {
		this.addFailureAtNode(node, `Unsafe global usage of ${node.text} in ${this._config.target}`);
	}

	super.visitIdentifier(node);
}

[bpasero]

After looking into this a bit more I am less optimistic that this can be done with TSLint 4. With TSLint 5 it actually looks better, given: https://github.com/palantir/tslint/blob/master/src/rules/noRestrictedGlobalsRule.ts

[bpasero]

landed via 90a35ec. Turns out you can do rules with resolved symbols and that allows to be smart.