Improved handling of (un)mounted drives/partitions.

richese provided base for new options.

i3pystatus/disk.py

@@ -13,25 +13,43 @@ class Disk(IntervalModule):
     """
 
     settings = (
-        "format", "path",
+        "format",
+        "path",
         ("divisor", "divide all byte values by this value, default is 1024**3 (gigabyte)"),
         ("display_limit", "if more space is available than this limit the module is hidden"),
         ("critical_limit", "critical space limit (see critical_color)"),
         ("critical_color", "the critical color"),
         ("color", "the common color"),
         ("round_size", "precision, None for INT"),
+        ("mounted_only", "display only if path is a valid mountpoint"),
+        "format_not_mounted",
+        "color_not_mounted"
     )
     required = ("path",)
     color = "#FFFFFF"
+    color_not_mounted = "#FFFFFF"
     critical_color = "#FF0000"
     format = "{free}/{avail}"
+    format_not_mounted = None
     divisor = 1024 ** 3
     display_limit = float('Inf')
     critical_limit = 0
     round_size = 2
+    mounted_only = False
 
     def run(self):
-        stat = os.statvfs(self.path)
+        try:
+            stat = os.statvfs(self.path)
+        except Exception:
+            if self.mounted_only:
+                self.output = {}
+            else:
+                self.output = {} if not self.format_not_mounted else {
+                    "full_text": self.format_not_mounted,
+                    "color": self.color_not_mounted,
+                }
+            return
+
         available = (stat.f_bsize * stat.f_bavail) / self.divisor
 
         if available > self.display_limit: