feat: Cache autodiscovery data

Use data from port autodisovery to pre-populate Ports cache.

Author: nbuchwitz

tests/helper.py

@@ -65,15 +65,15 @@ def register_port_details(
         fp.register(["uhubctl", "-l", self.path, "-p", str(port_number)], stdout=stdout)
 
     def cmd(
-        self,
-        fp: pytest_subprocess.FakeProcess,
-        port_number: int = None,
-        new_status: bool = None,
+        self, fp: pytest_subprocess.FakeProcess, port_number: int = None, new_status: bool = None, n_arg: bool = True
     ) -> None:
         if port_number is not None:
             assert port_number <= self.num_ports
 
-        cmd = ["uhubctl", "-N", "-l", str(self.path)]
+        cmd = ["uhubctl"]
+        if n_arg:
+            cmd.append("-N")
+        cmd += ["-l", str(self.path)]
         stdout = self.__stdout(port_filter=port_number)
 
         if port_number is not None:

tests/test_hub.py

@@ -45,22 +45,23 @@ def test_str():
 
 
 def test_port_enumeration(mock_hub: MockHub, fp: pytest_subprocess.FakeProcess):
-    mock_hub.cmd(fp)
+    mock_hub.cmd(fp, n_arg=False)
     mock_hub.discover_ports()
 
     assert len(mock_hub.ports) == 5
 
 
 def test_no_devices(fp: pytest_subprocess.FakeProcess):
     fp.register(["uhubctl", "-N"], stdout=["No compatible devices detected!".encode()])
+    fp.register(["uhubctl", "-v"], stdout="2.4.0-43-ge1e4d450")
 
     hubs = uhubctl.discover_hubs()
 
     assert hubs == []
 
 
 def test_find_port(mock_hub: MockHub, fp: pytest_subprocess.FakeProcess):
-    mock_hub.cmd(fp)
+    mock_hub.cmd(fp, n_arg=False)
     mock_hub.discover_ports()
 
     assert mock_hub.find_port(1) is not None

uhubctl/usb.py

@@ -96,11 +96,12 @@ def discover_ports(self) -> None:
         """
         pattern = re.compile(r"  Port (\d+): \d{4} ")
 
-        for line in UHubCtl.exec(["-l", self.path]):
+        for line in UHubCtl.exec(["-l", self.path], description=True):
             regex = pattern.match(line)
 
             if regex:
-                port = Port(self, regex.group(1))
+                # create Port object and pre-populate cache with line from autodiscovery
+                port = Port(self, regex.group(1), cache=line)
                 self.ports.append(port)
 
     def __str__(self) -> str:
@@ -116,7 +117,7 @@ class Port:
         r"  Port (?P<port>\d): \d{4} (?P<status>[a-z ]+)\s?(\[(?:(?P<vid>[a-f0-9]{4}):(?P<pid>[a-f0-9]{4})\s?(?P<description>.*)?)\])?"
     )
 
-    def __init__(self, hub: Hub, port_number: int):
+    def __init__(self, hub: Hub, port_number: int, cache: str = None):
         """
         Create new port instance
 
@@ -127,7 +128,7 @@ def __init__(self, hub: Hub, port_number: int):
         """
         self.hub = hub
         self.port_number = int(port_number)
-        self.__cache = None
+        self._cache = cache
 
     @property
     def status(self) -> bool:
@@ -170,8 +171,8 @@ def __attribute(self, name: str, cache: bool = True, result_filter: callable = N
             raise AttributeError(name)
 
         # use cache for port details if possible (fetching is slow)
-        if cache and self.__cache is not None:
-            lines = [self.__cache]
+        if cache and self._cache is not None:
+            lines = [self._cache]
         else:
             args = ["-l", self.hub.path, "-p", str(self.port_number)]
             lines = UHubCtl.exec(args, description=True)
@@ -183,7 +184,7 @@ def __attribute(self, name: str, cache: bool = True, result_filter: callable = N
                 if int(reg.group("port")) != self.port_number:
                     continue
 
-                self.__cache = line
+                self._cache = line
 
                 if callable(result_filter):
                     return result_filter(reg.group(name))