[PATCH 2/4] selftests: openvswitch: fix misc pylint warnings in ovs-dpctl.py

[Minxi Hou <houminxi@gmail.com>]

Fix miscellaneous pylint warnings with no behavior change:
  - W0611: remove unused import struct
  - W0702: replace bare except with except Exception
  - C0325: remove superfluous parentheses after return (3)
  - R1705: remove unnecessary elif after return (3)
  - W0108: replace unnecessary lambda with int
  - R1714: merge comparisons with in operator
  - W0719: replace raise Exception with raise ValueError
  - C1802: use implicit boolean test instead of len()
  - C0121: use is None instead of == None
  - R1719: simplify if-expression to bool test
  - R1703: simplify if/else to assignment expression
  - W0612: remove unused variables (keybits, maskbits, lst)
  - replace unused loop variable with underscore

Signed-off-by: Minxi Hou <houminxi@gmail.com>
---
base-commit: 9eab111e765729e93087ff86a2ec9b2ae42d0fa5
 .../selftests/net/openvswitch/ovs-dpctl.py    | 44 ++++++++-----------
 1 file changed, 19 insertions(+), 25 deletions(-)

diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
index 9cd0d8f0ab23..6a02810fe4ea 100644
--- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
+++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
@@ -11,7 +11,6 @@ import logging
 import math
 import multiprocessing
 import re
-import struct
 import sys
 import time
 import types
@@ -125,10 +124,7 @@ def parse_flags(flag_str, flag_vals):
         maskResult = int(digits, 0)
 
     while len(flag_str) > 0 and (flag_str[0] == "+" or flag_str[0] == "-"):
-        if flag_str[0] == "+":
-            setFlag = True
-        elif flag_str[0] == "-":
-            setFlag = False
+        setFlag = flag_str[0] == "+"
 
         flag_str = flag_str[1:]
 
@@ -221,10 +217,9 @@ def convert_int(size):
 
         if not value:
             return 0, 0
-        elif not mask:
+        if not mask:
             return int(value, 0), pow(2, size) - 1
-        else:
-            return int(value, 0), int(mask, 0)
+        return int(value, 0), int(mask, 0)
 
     return convert_int_sized
 
@@ -705,11 +700,11 @@ class ovsactions(nla):
                     parsed = True
                 else:
                     actstr = actstr[len("drop"): ]
-                    return (totallen - len(actstr))
+                    return totallen - len(actstr)
 
             elif parse_starts_block(actstr, r"^(\d+)", False, True):
                 actstr, output = parse_extract_field(
-                    actstr, None, r"(\d+)", lambda x: int(x), False, "0"
+                    actstr, None, r"(\d+)", int, False, "0"
                 )
                 self["attrs"].append(["OVS_ACTION_ATTR_OUTPUT", output])
                 parsed = True
@@ -761,12 +756,12 @@ class ovsactions(nla):
                         vid = int(v, 0)
                         if vid < 0 or vid > 0xFFF:
                             raise ValueError(
-                                f"push_vlan(): vid={int(vid)} out of range (0-4095)")
+                                f"push_vlan(): vid={vid} out of range (0-4095)")
                     elif k == "pcp":
                         pcp = int(v, 0)
                         if pcp < 0 or pcp > 7:
                             raise ValueError(
-                                f"push_vlan(): pcp={int(pcp)} out of range (0-7)")
+                                f"push_vlan(): pcp={pcp} out of range (0-7)")
                     elif k == "tpid":
                         tpid = int(v, 0)
                         if tpid < 0 or tpid > 0xFFFF:
@@ -804,7 +799,6 @@ class ovsactions(nla):
                 subacts = ovsactions()
                 actstr = actstr[len("clone("):]
                 parsedLen = subacts.parse(actstr)
-                lst = []
                 self["attrs"].append(("OVS_ACTION_ATTR_CLONE", subacts))
                 actstr = actstr[parsedLen:]
                 parsed = True
@@ -960,14 +954,14 @@ class ovsactions(nla):
                 actstr = actstr[1:]
 
             if len(actstr) and actstr[0] == ")":
-                return (totallen - len(actstr))
+                return totallen - len(actstr)
 
             actstr = actstr[strspn(actstr, ", ") :]
 
             if not parsed:
                 raise ValueError(f"Action str: '{actstr}' not supported")
 
-        return (totallen - len(actstr))
+        return totallen - len(actstr)
 
 
 # pyroute2 resolves nla_map types via getattr(self, name).
@@ -1057,8 +1051,6 @@ class ovskey(nla):
             if flowstr.startswith("("):
                 flowstr = flowstr[1:]
 
-            keybits = b""
-            maskbits = b""
             for f in self.fields_map:
                 if flowstr.startswith(f[1]):
                     # the following assumes that the field looks
@@ -1067,7 +1059,7 @@ class ovskey(nla):
                     flowstr = flowstr[len(f[1]) + 1 :]
                     splitchar = 0
                     for c in flowstr:
-                        if c == "," or c == ")":
+                        if c in (",", ")"):
                             break
                         splitchar += 1
                     data = flowstr[:splitchar]
@@ -1631,7 +1623,7 @@ class ovskey(nla):
             for prefix, regex, typ, attr_name, mask_val, default_val, v46_flag in fields:
                 flowstr, value = parse_extract_field(flowstr, prefix, regex, typ, False)
                 if not attr_name:
-                    raise Exception("Bad list value in tunnel fields")
+                    raise ValueError("Bad list value in tunnel fields")
 
                 if value is None and attr_name in forced_include:
                     value = default_val
@@ -1714,7 +1706,7 @@ class ovskey(nla):
                 if not noprint:
                     print_str += ","
 
-            if len(flagsattrs):
+            if flagsattrs:
                 print_str += f"flags({'|'.join(flagsattrs)})"
             print_str += ")"
             return print_str
@@ -2304,7 +2296,7 @@ class OvsDatapath(GenericNetlinkSocket):
 
             nproc = multiprocessing.cpu_count()
             procarray = []
-            for i in range(1, nproc):
+            for _ in range(1, nproc):
                 procarray += [int(p.epid)]
             msg["attrs"].append(["OVS_DP_ATTR_UPCALL_PID", procarray])
         msg["attrs"].append(["OVS_DP_ATTR_USER_FEATURES", dpfeatures])
@@ -2379,15 +2371,17 @@ class OvsVport(GenericNetlinkSocket):
     def type_to_str(vport_type):
         if vport_type == OvsVport.OVS_VPORT_TYPE_NETDEV:
             return "netdev"
-        elif vport_type == OvsVport.OVS_VPORT_TYPE_INTERNAL:
+        if vport_type == OvsVport.OVS_VPORT_TYPE_INTERNAL:
             return "internal"
+
         raise ValueError(f"Unknown vport type:{int(vport_type)}")
 
     def str_to_type(vport_type):
         if vport_type in ["netdev", "gre", "vxlan", "geneve"]:
             return OvsVport.OVS_VPORT_TYPE_NETDEV
-        elif vport_type == "internal":
+        if vport_type == "internal":
             return OvsVport.OVS_VPORT_TYPE_INTERNAL
+
         raise ValueError(f"Unknown vport type: '{vport_type}'")
 
     def __init__(self, packet=OvsPacket()):
@@ -2482,7 +2476,7 @@ class OvsVport(GenericNetlinkSocket):
         msg["dpifindex"] = dpindex
         msg["attrs"].append(["OVS_VPORT_ATTR_NAME", vport_ifname])
 
-        if p == None:
+        if p is None:
             p = self.upcall_packet
         else:
             self.upcall_packet = p
@@ -3068,7 +3062,7 @@ def main(argv):
             return 1
         rep = ovsflow.dump(rep["dpifindex"])
         for flow in rep:
-            print(flow.dpstr(True if args.verbose > 0 else False))
+            print(flow.dpstr(args.verbose > 0))
     elif hasattr(args, "flbr"):
         rep = ovsdp.info(args.flbr, 0)
         if rep is None:
-- 
2.55.0