chrome/browser/ui/browser_list_enumerator.cc

// Copyright 2025 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "chrome/browser/ui/browser_list_enumerator.h"

#include <algorithm>

#include "base/check.h"
#include "base/containers/contains.h"

BrowserListEnumerator::BrowserListEnumerator(bool enumerate_new_browser)
    : enumerate_new_browser_(enumerate_new_browser),
      browsers_(BrowserList::GetInstance()->begin(),
                BrowserList::GetInstance()->end()) {
  BrowserList::GetInstance()->AddObserver(this);
}

BrowserListEnumerator::~BrowserListEnumerator() {
  BrowserList::GetInstance()->RemoveObserver(this);
}

void BrowserListEnumerator::OnBrowserAdded(Browser* browser) {
  DCHECK(!base::Contains(browsers_, browser));
  if (enumerate_new_browser_) {
    browsers_.push_back(browser);
  }
}

void BrowserListEnumerator::OnBrowserRemoved(Browser* browser) {
  std::erase(browsers_, browser);
}

Browser* BrowserListEnumerator::Next() {
  Browser* browser = browsers_.front();
  browsers_.erase(browsers_.begin());
  DCHECK(base::Contains(*BrowserList::GetInstance(), browser));
  return browser;
}