private registerListeners()

in src/view/reviewManager.ts [101:167]
51 lines of code
17 McCabe index (conditional complexity)

	private registerListeners(): void {
		this._disposables.push(
			this._repository.state.onDidChange(_ => {
				const oldHead = this._previousRepositoryState.HEAD;
				const newHead = this._repository.state.HEAD;

				if (!oldHead && !newHead) {
					// both oldHead and newHead are undefined
					return;
				}

				let sameUpstream;

				if (!oldHead || !newHead) {
					sameUpstream = false;
				} else {
					sameUpstream = !!oldHead.upstream
						? newHead.upstream &&
						oldHead.upstream.name === newHead.upstream.name &&
						oldHead.upstream.remote === newHead.upstream.remote
						: !newHead.upstream;
				}

				const sameHead =
					sameUpstream && // falsy if oldHead or newHead is undefined.
					oldHead!.ahead === newHead!.ahead &&
					oldHead!.behind === newHead!.behind &&
					oldHead!.commit === newHead!.commit &&
					oldHead!.name === newHead!.name &&
					oldHead!.remote === newHead!.remote &&
					oldHead!.type === newHead!.type;

				const remotes = parseRepositoryRemotes(this._repository);
				const sameRemotes =
					this._previousRepositoryState.remotes.length === remotes.length &&
					this._previousRepositoryState.remotes.every(remote => remotes.some(r => remote.equals(r)));

				if (!sameHead || !sameRemotes) {
					this._previousRepositoryState = {
						HEAD: this._repository.state.HEAD,
						remotes: remotes,
					};

					// The first time this event occurs we do want to do visible updates.
					// The first time, oldHead will be undefined.
					// For subsequent changes, we don't want to make visible updates.
					// This occurs on branch changes.
					// Note that the visible changes will occur when checking out a PR.
					this.updateState(true);
				}
			}),
		);

		this._disposables.push(
			vscode.workspace.onDidChangeConfiguration(_ => {
				this.updateFocusedViewMode();
			}),
		);

		this._disposables.push(
			this._folderRepoManager.onDidChangeActivePullRequest(_ => {
				this.updateFocusedViewMode();
			}),
		);

		GitHubCreatePullRequestLinkProvider.registerProvider(this._disposables, this, this._folderRepoManager);
	}