tests: replace pycodestyle with black

Drop pycodestyle for code style checking in favor of black. Black is
much faster, stable PEP8 compliant code style checker offering also
automatic formatting. It aims to be very stable and produce smallest
diffs. It's used by many small and big projects.

Running checkstyle with black takes a few seconds with a terse output.
Thus, test-checkstyle-diff is no longer necessary.

Expand scope of checkstyle to all python files in the repo, replacing
test-checkstyle with checkstyle-python.

Also, fixstyle-python is now available for automatic style formatting.

Note: python virtualenv has been consolidated in test/Makefile,
test/requirements*.txt which will eventually be moved to a central
location.  This is required to simply the automated generation of
docker executor images in the CI.

Type: improvement
Change-Id: I022a326603485f58585e879ac0f697fceefbc9c8
Signed-off-by: Klement Sekera <klement.sekera@gmail.com>
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>
diff --git a/src/scripts/host-stack/cc_plots.py b/src/scripts/host-stack/cc_plots.py
index 20f5bd6..f0296af 100755
--- a/src/scripts/host-stack/cc_plots.py
+++ b/src/scripts/host-stack/cc_plots.py
@@ -6,214 +6,242 @@
 import matplotlib.pyplot as plt
 from matplotlib.lines import Line2D
 
-class Point():
+
+class Point:
     "CC event"
+
     def __init__(self, x, y):
         self.x = x
         self.y = y
 
+
 def listx(points):
-  return list(map(lambda pt: pt.x, points))
+    return list(map(lambda pt: pt.x, points))
+
 
 def listy(points):
-  return list(map(lambda pt: pt.y, points))
+    return list(map(lambda pt: pt.y, points))
+
 
 def plot_data(d):
 
-  plt.figure(1)
+    plt.figure(1)
 
-  cwndx = listx(d["cwnd"])
-  cwndy = listy(d["cwnd"])
-  congx = listx(d["congestion"])
-  congy = listy(d["congestion"])
-  rcvrdx = listx(d["recovered"])
-  rcvrdy = listy(d["recovered"])
-  rxttx = listx(d["rxtTimeout"])
-  rxtty = listy(d["rxtTimeout"])
+    cwndx = listx(d["cwnd"])
+    cwndy = listy(d["cwnd"])
+    congx = listx(d["congestion"])
+    congy = listy(d["congestion"])
+    rcvrdx = listx(d["recovered"])
+    rcvrdy = listy(d["recovered"])
+    rxttx = listx(d["rxtTimeout"])
+    rxtty = listy(d["rxtTimeout"])
 
-  # cwnd/ssthresh/cc events
-  plt.subplot(311)
-  plt.title("cwnd/ssthresh")
-  pcwnd = plt.plot(cwndx, cwndy, 'r')
-  psst = plt.plot(cwndx, d["ssthresh"], 'y-')
-  pcong = plt.plot(congx, congy,'yo')
-  precov = plt.plot(rcvrdx, rcvrdy,'co')
-  prxtt = plt.plot(rxttx, rxtty,'mo')
+    # cwnd/ssthresh/cc events
+    plt.subplot(311)
+    plt.title("cwnd/ssthresh")
+    pcwnd = plt.plot(cwndx, cwndy, "r")
+    psst = plt.plot(cwndx, d["ssthresh"], "y-")
+    pcong = plt.plot(congx, congy, "yo")
+    precov = plt.plot(rcvrdx, rcvrdy, "co")
+    prxtt = plt.plot(rxttx, rxtty, "mo")
 
-  marker1 = Line2D(range(1), range(1), color="r")
-  marker2 = Line2D(range(1), range(1), color="y")
-  marker3 = Line2D(range(1), range(1), color="w", marker="o", markerfacecolor="y")
-  marker4 = Line2D(range(1), range(1), color="w", marker="o", markerfacecolor="c")
-  marker5 = Line2D(range(1), range(1), color="w", marker="o", markerfacecolor="m")
-  plt.legend((marker1, marker2, marker3, marker4, marker5),
-             ('cwnd', 'ssthresh', 'congestion', 'recovered', 'rxt-timeout'),
-             loc=4)
-  axes = plt.gca()
-  axes.set_ylim([-20e4, max(cwndy) + 20e4])
+    marker1 = Line2D(range(1), range(1), color="r")
+    marker2 = Line2D(range(1), range(1), color="y")
+    marker3 = Line2D(range(1), range(1), color="w", marker="o", markerfacecolor="y")
+    marker4 = Line2D(range(1), range(1), color="w", marker="o", markerfacecolor="c")
+    marker5 = Line2D(range(1), range(1), color="w", marker="o", markerfacecolor="m")
+    plt.legend(
+        (marker1, marker2, marker3, marker4, marker5),
+        ("cwnd", "ssthresh", "congestion", "recovered", "rxt-timeout"),
+        loc=4,
+    )
+    axes = plt.gca()
+    axes.set_ylim([-20e4, max(cwndy) + 20e4])
 
-  # snd variables
-  plt.subplot(312)
-  plt.title("cc variables")
-  plt.plot(cwndx, d["space"], 'g-', markersize=1)
-  plt.plot(cwndx, d["flight"], 'b-', markersize=1)
-  plt.plot(cwndx, d["sacked"], 'm:', markersize=1)
-  plt.plot(cwndx, d["lost"], 'y:', markersize=1)
-  plt.plot(cwndx, d["cc-space"], 'k:', markersize=1)
-  plt.plot(cwndx, cwndy, 'ro', markersize=2)
+    # snd variables
+    plt.subplot(312)
+    plt.title("cc variables")
+    plt.plot(cwndx, d["space"], "g-", markersize=1)
+    plt.plot(cwndx, d["flight"], "b-", markersize=1)
+    plt.plot(cwndx, d["sacked"], "m:", markersize=1)
+    plt.plot(cwndx, d["lost"], "y:", markersize=1)
+    plt.plot(cwndx, d["cc-space"], "k:", markersize=1)
+    plt.plot(cwndx, cwndy, "ro", markersize=2)
 
-  plt.plot(congx, congy, 'y^', markersize=10, markerfacecolor="y")
-  plt.plot(rcvrdx, rcvrdy, 'c^', markersize=10, markerfacecolor="c")
-  plt.plot(rxttx, rxtty, 'm^', markersize=10, markerfacecolor="m")
+    plt.plot(congx, congy, "y^", markersize=10, markerfacecolor="y")
+    plt.plot(rcvrdx, rcvrdy, "c^", markersize=10, markerfacecolor="c")
+    plt.plot(rxttx, rxtty, "m^", markersize=10, markerfacecolor="m")
 
-  #plt.plot(cwndx, d["snd_wnd"], 'ko', markersize=1)
-  plt.legend(("snd-space", "flight", "sacked", "lost", "cc-space", "cwnd",
-              "congestion", "recovered", "rxt-timeout"),
-             loc=1)
+    # plt.plot(cwndx, d["snd_wnd"], 'ko', markersize=1)
+    plt.legend(
+        (
+            "snd-space",
+            "flight",
+            "sacked",
+            "lost",
+            "cc-space",
+            "cwnd",
+            "congestion",
+            "recovered",
+            "rxt-timeout",
+        ),
+        loc=1,
+    )
 
-  # rto/srrt/rttvar
-  plt.subplot(313)
-  plt.title("rtt")
-  plt.plot(cwndx, d["srtt"], 'g-')
-  plt.plot(cwndx, [x/1000 for x in d["mrtt-us"]], 'r-')
-  plt.plot(cwndx, d["rttvar"], 'b-')
-  plt.legend(["srtt", "mrtt-us", "rttvar"])
-  axes = plt.gca()
-  #plt.plot(cwndx, rto, 'r-')
-  #axes.set_ylim([0, int(max(rto[2:len(rto)])) + 50])
+    # rto/srrt/rttvar
+    plt.subplot(313)
+    plt.title("rtt")
+    plt.plot(cwndx, d["srtt"], "g-")
+    plt.plot(cwndx, [x / 1000 for x in d["mrtt-us"]], "r-")
+    plt.plot(cwndx, d["rttvar"], "b-")
+    plt.legend(["srtt", "mrtt-us", "rttvar"])
+    axes = plt.gca()
+    # plt.plot(cwndx, rto, 'r-')
+    # axes.set_ylim([0, int(max(rto[2:len(rto)])) + 50])
 
-  # show
-  plt.show()
+    # show
+    plt.show()
 
-def find_pattern(file_path,session_idx):
+
+def find_pattern(file_path, session_idx):
     is_active_open = 1
     listener_pattern = "l\[\d\]"
-    if (is_active_open):
-      initial_pattern = "\[\d\](\.\d+:\d+\->\.\d+:\d+)\s+open:\s"
+    if is_active_open:
+        initial_pattern = "\[\d\](\.\d+:\d+\->\.\d+:\d+)\s+open:\s"
     else:
-      initial_pattern = "\[\d\](\.\d+:\d+\->\.\d+:\d+)\s"
+        initial_pattern = "\[\d\](\.\d+:\d+\->\.\d+:\d+)\s"
     idx = 0
-    f = open(file_path, 'r')
+    f = open(file_path, "r")
     for line in f:
-      # skip listener lines (server)
-      if (re.search(listener_pattern, line) != None):
-        continue
-      match = re.search(initial_pattern, line)
-      if (match == None):
-        continue
-      if (idx < session_idx):
-        idx += 1
-        continue
-      filter_pattern = str(match.group(1)) + "\s+(.+)"
-      print ("pattern is %s" % filter_pattern)
-      f.close()
-      return filter_pattern
-    raise Exception ("Could not find initial pattern")
+        # skip listener lines (server)
+        if re.search(listener_pattern, line) != None:
+            continue
+        match = re.search(initial_pattern, line)
+        if match == None:
+            continue
+        if idx < session_idx:
+            idx += 1
+            continue
+        filter_pattern = str(match.group(1)) + "\s+(.+)"
+        print("pattern is %s" % filter_pattern)
+        f.close()
+        return filter_pattern
+    raise Exception("Could not find initial pattern")
+
 
 def compute_time(min, sec, msec):
-  return int(min)*60 + int(sec) + int(msec)/1000.0
+    return int(min) * 60 + int(sec) + int(msec) / 1000.0
+
 
 def run(file_path, session_idx):
     filter_sessions = 1
     filter_pattern = ""
 
     patterns = {
-      "time"      : "^\d+:(\d+):(\d+):(\d+):\d+",
-      "listener"  : "l\[\d\]",
-      "cc"        : "cwnd (\d+) flight (\d+) space (\d+) ssthresh (\d+) snd_wnd (\d+)",
-      "cc-snd"    : "cc_space (\d+) sacked (\d+) lost (\d+)",
-      "rtt"       : "rto (\d+) srtt (\d+) mrtt-us (\d+) rttvar (\d+)",
-      "rxtt"      : "rxt-timeout",
-      "congestion": "congestion",
-      "recovered" : "recovered",
+        "time": "^\d+:(\d+):(\d+):(\d+):\d+",
+        "listener": "l\[\d\]",
+        "cc": "cwnd (\d+) flight (\d+) space (\d+) ssthresh (\d+) snd_wnd (\d+)",
+        "cc-snd": "cc_space (\d+) sacked (\d+) lost (\d+)",
+        "rtt": "rto (\d+) srtt (\d+) mrtt-us (\d+) rttvar (\d+)",
+        "rxtt": "rxt-timeout",
+        "congestion": "congestion",
+        "recovered": "recovered",
     }
     d = {
-      "cwnd"        : [],
-      "space"       : [],
-      "flight"      : [],
-      "ssthresh"    : [],
-      "snd_wnd"     : [],
-      "cc-space"    : [],
-      "lost"        : [],
-      "sacked"      : [],
-      "rto"         : [],
-      "srtt"        : [],
-      "mrtt-us"     : [],
-      "rttvar"      : [],
-      "rxtTimeout"  : [],
-      "congestion"  : [],
-      "recovered"   : [],
+        "cwnd": [],
+        "space": [],
+        "flight": [],
+        "ssthresh": [],
+        "snd_wnd": [],
+        "cc-space": [],
+        "lost": [],
+        "sacked": [],
+        "rto": [],
+        "srtt": [],
+        "mrtt-us": [],
+        "rttvar": [],
+        "rxtTimeout": [],
+        "congestion": [],
+        "recovered": [],
     }
 
-    if (filter_sessions):
+    if filter_sessions:
         filter_pattern = find_pattern(file_path, session_idx)
-    f = open(file_path, 'r')
+    f = open(file_path, "r")
 
     stats_index = 0
     start_time = 0
 
     for line in f:
         # skip listener lines (server)
-        if (re.search(patterns["listener"], line) != None):
+        if re.search(patterns["listener"], line) != None:
             continue
         # filter sessions
-        if (filter_sessions):
+        if filter_sessions:
             match = re.search(filter_pattern, line)
-            if (match == None):
+            if match == None:
                 continue
 
         original_line = line
         line = match.group(1)
-        match = re.search (patterns["time"], original_line)
-        if (match == None):
-          print "something went wrong! no time!"
-          continue
-        time = compute_time (match.group(1), match.group(2), match.group(3))
-        if (start_time == 0):
-          start_time = time
+        match = re.search(patterns["time"], original_line)
+        if match == None:
+            print("something went wrong! no time!")
+            continue
+        time = compute_time(match.group(1), match.group(2), match.group(3))
+        if start_time == 0:
+            start_time = time
 
         time = time - start_time
         match = re.search(patterns["cc"], line)
-        if (match != None):
-          d["cwnd"].append(Point(time, int(match.group(1))))
-          d["flight"].append(int(match.group(2)))
-          d["space"].append(int(match.group(3)))
-          d["ssthresh"].append(int(match.group(4)))
-          d["snd_wnd"].append(int(match.group(5)))
-          stats_index += 1
-          continue
+        if match != None:
+            d["cwnd"].append(Point(time, int(match.group(1))))
+            d["flight"].append(int(match.group(2)))
+            d["space"].append(int(match.group(3)))
+            d["ssthresh"].append(int(match.group(4)))
+            d["snd_wnd"].append(int(match.group(5)))
+            stats_index += 1
+            continue
         match = re.search(patterns["cc-snd"], line)
-        if (match != None):
-          d["cc-space"].append(int(match.group(1)))
-          d["sacked"].append(int(match.group(2)))
-          d["lost"].append(int(match.group(3)))
+        if match != None:
+            d["cc-space"].append(int(match.group(1)))
+            d["sacked"].append(int(match.group(2)))
+            d["lost"].append(int(match.group(3)))
         match = re.search(patterns["rtt"], line)
-        if (match != None):
-           d["rto"].append(int(match.group(1)))
-           d["srtt"].append(int(match.group(2)))
-           d["mrtt-us"].append(int(match.group(3)))
-           d["rttvar"].append(int(match.group(4)))
-        if (stats_index == 0):
-           continue
+        if match != None:
+            d["rto"].append(int(match.group(1)))
+            d["srtt"].append(int(match.group(2)))
+            d["mrtt-us"].append(int(match.group(3)))
+            d["rttvar"].append(int(match.group(4)))
+        if stats_index == 0:
+            continue
         match = re.search(patterns["rxtt"], line)
-        if (match != None):
-          d["rxtTimeout"].append(Point(time, d["cwnd"][stats_index - 1].y + 1e4))
-          continue
+        if match != None:
+            d["rxtTimeout"].append(Point(time, d["cwnd"][stats_index - 1].y + 1e4))
+            continue
         match = re.search(patterns["congestion"], line)
-        if (match != None):
-          d["congestion"].append(Point(time, d["cwnd"][stats_index - 1].y - 1e4))
-          continue
+        if match != None:
+            d["congestion"].append(Point(time, d["cwnd"][stats_index - 1].y - 1e4))
+            continue
         match = re.search(patterns["recovered"], line)
-        if (match != None):
-          d["recovered"].append(Point(time, d["cwnd"][stats_index - 1].y))
-          continue
+        if match != None:
+            d["recovered"].append(Point(time, d["cwnd"][stats_index - 1].y))
+            continue
 
     plot_data(d)
 
+
 if __name__ == "__main__":
     parser = argparse.ArgumentParser(description="Plot tcp cc logs")
-    parser.add_argument('-f', action='store', dest='file', required=True,
-                        help="elog file in txt format")
-    parser.add_argument('-s', action='store', dest='session_index', default=0,
-                        help="session index for which to plot cc logs" )
+    parser.add_argument(
+        "-f", action="store", dest="file", required=True, help="elog file in txt format"
+    )
+    parser.add_argument(
+        "-s",
+        action="store",
+        dest="session_index",
+        default=0,
+        help="session index for which to plot cc logs",
+    )
     results = parser.parse_args()
     run(results.file, int(results.session_index))