Avoid crashing if a device disconnects mid-diags

scripts/wk/hw/diags.py

@@ -642,6 +642,11 @@ def disk_smart_status_check(dev, mid_run=True) -> None:
   color = None
   disable_tests = False
 
+  # Bail if dev is missing
+  if not dev.present:
+    dev.disable_disk_tests()
+    return
+
   # Check SMART status and attributes
   if not hw_smart.smart_status_ok(dev):
     msg = 'Critical SMART error detected'

scripts/wk/hw/disk.py

@@ -151,12 +151,23 @@ class Disk:
 
     return aligned
 
+  @property
+  def present(self) -> bool:
+    """Verify this device is still present, returns bool."""
+    if not self.path.exists():
+      self.add_note('Device disconnected', 'RED')
+      return False
+    return True
+
   def update_details(self, skip_children=True) -> None:
     """Update disk details using OS specific methods.
 
     Required details default to generic descriptions
     and are converted to the correct type.
     """
+    if not self.present:
+      return
+
     if PLATFORM == 'Darwin':
       self.raw_details = get_disk_details_macos(
         self.path, skip_children=skip_children,

scripts/wk/hw/smart.py

@@ -380,6 +380,11 @@ def update_smart_details(dev) -> None:
   """Update SMART details via smartctl."""
   updated_attributes = {}
 
+  # Bail if device was disconnected
+  if not dev.present:
+    dev.add_note('Device disconnected', 'RED')
+    return
+
   # Get SMART data
   cmd = [
     'sudo',

scripts/wk/os/linux.py

@@ -205,6 +205,10 @@ def mount_volumes(device_path=None, read_write=False, scan_corestorage=False):
     cmd.append(device_path)
   json_data = get_json_from_command(cmd)
 
+  # Bail if json_data is empty
+  if not json_data:
+    return
+
   # Build list of volumes
   for dev in json_data.get('blockdevices', [{}]):
     volumes.extend(_get_volumes(dev))