[CODE] Refactor default browser fetching

browser_history/browsers.py

@@ -180,7 +180,7 @@ class Edge(ChromiumBasedBrowser):
     """
 
     name = "Edge"
-    aliases = ("msedgehtm", "msedge")
+    aliases = ("msedgehtm", "msedge", "microsoft-edge")
 
     windows_path = "AppData/Local/Microsoft/Edge/User Data"
     mac_path = "Library/Application Support/Microsoft Edge"

browser_history/utils.py

@@ -6,7 +6,7 @@
 import inspect
 import logging
 import platform
-import webbrowser
+import subprocess
 
 from . import generic
 
@@ -83,6 +83,32 @@ def get_subclasses(browser):
     import winreg  # type: ignore
 
 
+def _default_browser_linux():
+    try:
+        cmd = "xdg-settings get default-web-browser".split()
+        raw_result = subprocess.check_output(cmd, stderr=subprocess.DEVNULL)
+        # most have a suffix ".desktop" so just remove it
+        default = raw_result.decode().strip().lower().replace(".desktop", "")
+    except (FileNotFoundError, subprocess.CalledProcessError, PermissionError):
+        logger.warning("Could not determine default browser")
+        default = None
+
+    return default
+
+
+def _default_browser_win():
+    reg_path = (
+        "Software\\Microsoft\\Windows\\Shell\\Associations\\"
+        "UrlAssociations\\https\\UserChoice"
+    )
+    with winreg.OpenKey(winreg.HKEY_CURRENT_USER, reg_path) as key:
+        default = winreg.QueryValueEx(key, "ProgId")
+        if default is None:
+            logger.warning("Could not determine default browser")
+            return None
+        return default[0].lower()
+
+
 def default_browser():
     """This method gets the default browser of the current platform
 
@@ -98,26 +124,17 @@ def default_browser():
 
     # Always try to return a lower-cased value for ease of comparison
     if plat == Platform.LINUX:
-        default = webbrowser.get()
-        if default is None or default.name is None:
-            logger.warning("Could not determine default browser")
-            return None
-        default = default.name.lower()
+        default = _default_browser_linux()
     elif plat == Platform.WINDOWS:
-        reg_path = (
-            "Software\\Microsoft\\Windows\\Shell\\Associations\\"
-            "UrlAssociations\\https\\UserChoice"
-        )
-        with winreg.OpenKey(winreg.HKEY_CURRENT_USER, reg_path) as key:
-            default = winreg.QueryValueEx(key, "ProgId")
-            if default is None:
-                logger.warning("Could not determine default browser")
-                return None
-            default = default[0].lower()
+        default = _default_browser_win()
     else:
         logger.warning("Default browser feature not supported on this OS")
         return None
 
+    if default is None:
+        # no need to continue checking default
+        return None
+
     # ---- convert obtained default to something we understand ----
     all_browsers = get_browsers()
 

tests/test_default_browser.py

@@ -1,31 +1,19 @@
 # noqa: F401, F811
 # pylint: disable=redefined-outer-name,unused-argument,unused-import
 
-import webbrowser
-
 import pytest
 
-from browser_history.utils import default_browser, get_platform, Platform
-from browser_history import browsers
+from browser_history import browsers, utils
 
 from .utils import become_mac, become_linux, become_windows  # noqa: F401
 
 
-platform = get_platform()
-if platform == Platform.WINDOWS:
-    import winreg
-
-
-class MockBrowser:
-    """Mock version of return value of webbrowser.get()"""
-
-    def __init__(self, name=None):
-        self.name = name
+platform = utils.get_platform()
 
 
 @pytest.fixture
-def change_webbrowser_default(monkeypatch, request):
-    """Changes webbrowser.get() to return a specific named
+def change_linux_default(monkeypatch, request):
+    """Changes utils._default_browser_linux to return a specific named
     browser. use @pytest.mark.browser_name(name) to set
     browser name
     """
@@ -38,19 +26,17 @@ def change_webbrowser_default(monkeypatch, request):
         browser_name = marker.args[0]
 
     def mock_get():
-        return MockBrowser(name=browser_name)
+        return browser_name
 
-    monkeypatch.setattr(webbrowser, "get", mock_get)
+    monkeypatch.setattr(utils, "_default_browser_linux", mock_get)
 
 
 @pytest.fixture
-def change_reg_browser_default(monkeypatch, request):
-    """Changes webbrowser.get() to return a specific named
+def change_win_default(monkeypatch, request):
+    """Changes utils._default_browser_win to return a specific named
     browser. use @pytest.mark.browser_name(name) to set
     browser name
     """
-    if platform != Platform.WINDOWS:
-        pytest.skip("Skipping windows registry based test")
 
     marker = request.node.get_closest_marker("browser_name")
 
@@ -59,55 +45,57 @@ def change_reg_browser_default(monkeypatch, request):
     else:
         browser_name = marker.args[0]
 
-    def mock_QueryValueEx(key1, key2):
-        return [browser_name] if browser_name is not None else None
+    def mock_get():
+        return browser_name
 
-    monkeypatch.setattr(winreg, "QueryValueEx", mock_QueryValueEx)
+    monkeypatch.setattr(utils, "_default_browser_win", mock_get)
 
 
 @pytest.mark.browser_name("firefox")
-def test_default_firefox(become_linux, change_webbrowser_default):  # noqa: F811
+def test_default_firefox(become_linux, change_linux_default):  # noqa: F811
     """Test that firefox set as default is recognised
     correctly"""
-    assert default_browser() == browsers.Firefox
+    assert utils.default_browser() == browsers.Firefox
 
 
 @pytest.mark.browser_name("chromehtml")
-def test_default_chrome(become_linux, change_webbrowser_default):  # noqa: F811
+def test_default_chrome(become_linux, change_linux_default):  # noqa: F811
     """Test that Chrome set as default is recognised
     correctly"""
-    assert default_browser() == browsers.Chrome
+    assert utils.default_browser() == browsers.Chrome
 
 
-def test_default_none(become_linux, change_webbrowser_default):  # noqa: F811
+def test_default_none(become_linux, change_linux_default):  # noqa: F811
     """Test that no default set returns None"""
-    assert default_browser() is None
+    assert utils.default_browser() is None
 
 
 @pytest.mark.browser_name("safari")
-def test_default_safari(become_mac, change_webbrowser_default):  # noqa: F811
+def test_default_safari(become_mac, change_linux_default):  # noqa: F811
     """Test that Safari set as default in MacOS is NOT
     recognised correctly since default browser in MacOS is not
     supported."""
-    assert default_browser() is None
+    assert utils.default_browser() is None
 
 
 @pytest.mark.browser_name("chromehtml")
-def test_default_windows_chrome(
-    become_windows, change_reg_browser_default  # noqa: F811
-):
+def test_default_windows_chrome(become_windows, change_win_default):  # noqa: F811
     """Test that chrome is identified correctly on Windows"""
-    assert default_browser() == browsers.Chrome
+    assert utils.default_browser() == browsers.Chrome
+
+
+@pytest.mark.browser_name("firefoxurl-308046b0af4a39cb")
+def test_default_windows_firefox(become_windows, change_win_default):  # noqa: F811
+    """Test that firefox is identified correctly on Windows"""
+    assert utils.default_browser() == browsers.Firefox
 
 
-@pytest.mark.browser_name("firefoxurl")
-def test_default_windows_firefox(
-    become_windows, change_reg_browser_default  # noqa: F811
-):
+@pytest.mark.browser_name("idontexist-browser")
+def test_default_unknown(become_windows, change_win_default):  # noqa: F811
     """Test that firefox is identified correctly on Windows"""
-    assert default_browser() == browsers.Firefox
+    assert utils.default_browser() is None
 
 
-def test_default_windows_none(become_windows, change_reg_browser_default):  # noqa: F811
+def test_default_windows_none(become_windows, change_win_default):  # noqa: F811
     """Test that registry returning None is handled correctly"""
-    assert default_browser() is None
+    assert utils.default_browser() is None