Fix all flake8 issues on python 3

.flake8

@@ -1,10 +1,11 @@
 [flake8]
-ignore = E111,E114,E501,E261,E266,E121,E402,E241
+ignore = E111,E114,E501,E261,E266,E121,E402,E241,W504
 exclude =
  ./third_party/, # third-party code
  ./tools/filelock.py, # third-party code
  ./tools/scons/, # third-party code
  ./tests/freetype/src/, # third-party code
+ ./tests/poppler/poppler/, # third-party code
  ./site/source/conf.py,
  ./tools/debug/,
  ./tools/emdump.py,

emar.py

@@ -78,7 +78,7 @@ def run():
           newargs[j] = full_newname
           to_delete.append(full_newname)
           contents.add(newname)
-        except:
+        except Exception:
           # it is ok to fail here, we just don't get hashing
           contents.add(basename)
           pass

emcc.py

@@ -503,7 +503,7 @@ def run(args):
   if '--version' in args:
     try:
       revision = run_process(['git', 'show'], stdout=PIPE, stderr=PIPE, cwd=shared.path_from_root()).stdout.splitlines()[0]
-    except:
+    except Exception:
       revision = '(unknown revision)'
     print('''emcc (Emscripten gcc/clang-like replacement) %s (%s)
 Copyright (C) 2014 the Emscripten authors (see AUTHORS.txt)
@@ -631,7 +631,7 @@ def is_minus_s_for_emcc(args, i):
           src = open(arg).read()
           if debug_configure:
             open(tempout, 'a').write('============= ' + arg + '\n' + src + '\n=============\n\n')
-        except:
+        except IOError:
           pass
       elif arg.endswith('.s'):
         if debug_configure:
@@ -721,7 +721,7 @@ def filter_emscripten_options(argv):
       open(target, 'w').write('#!' + full_node + '\n' + src) # add shebang
       try:
         os.chmod(target, stat.S_IMODE(os.stat(target).st_mode) | stat.S_IXUSR) # make executable
-      except:
+      except OSError:
         pass # can fail if e.g. writing the executable to /dev/null
     return ret
 
@@ -862,7 +862,7 @@ def optimizing(opts):
           newargs[i] = newargs[i + 1] = ''
           if key == 'WASM_BACKEND=1':
             exit_with_error('do not set -s WASM_BACKEND, instead set EMCC_WASM_BACKEND=1 in the environment')
-    newargs = [arg for arg in newargs if arg is not '']
+    newargs = [arg for arg in newargs if arg != '']
 
     settings_key_changes = set()
     for s in settings_changes:
@@ -929,14 +929,14 @@ def optimizing(opts):
             input_files.append((i, arg))
           elif file_suffix.endswith(STATICLIB_ENDINGS + DYNAMICLIB_ENDINGS):
             # if it's not, and it's a library, just add it to libs to find later
-            l = unsuffixed_basename(arg)
+            libname = unsuffixed_basename(arg)
             for prefix in LIB_PREFIXES:
               if not prefix:
                 continue
-              if l.startswith(prefix):
-                l = l[len(prefix):]
+              if libname.startswith(prefix):
+                libname = libname[len(prefix):]
                 break
-            libs.append((i, l))
+            libs.append((i, libname))
             newargs[i] = ''
           else:
             logger.warning(arg + ' is not a valid input file')
@@ -982,7 +982,7 @@ def optimizing(opts):
 
     original_input_files = input_files[:]
 
-    newargs = [a for a in newargs if a is not '']
+    newargs = [a for a in newargs if a != '']
 
     has_dash_c = '-c' in newargs
     has_dash_S = '-S' in newargs
@@ -3122,7 +3122,7 @@ def generate_minimal_runtime_html(target, options, js_target, target_basename,
                                   memfile, optimizer):
   logger.debug('generating HTML for minimal runtime')
   shell = read_and_preprocess(options.shell_path)
-  if re.search('{{{\s*SCRIPT\s*}}}', shell):
+  if re.search(r'{{{\s*SCRIPT\s*}}}', shell):
     exit_with_error('--shell-file "' + options.shell_path + '": MINIMAL_RUNTIME uses a different kind of HTML page shell file than the traditional runtime! Please see $EMSCRIPTEN/src/shell_minimal_runtime.html for a template to use as a basis.')
 
   shell = shell.replace('{{{ TARGET_BASENAME }}}', target_basename)
@@ -3528,7 +3528,7 @@ def parse_string_list(text):
     # simpler syntaxes
     try:
       return json.loads(text)
-    except:
+    except ValueError:
       return parse_string_list(text)
 
   try:
@@ -3540,12 +3540,13 @@ def parse_string_list(text):
 def validate_arg_level(level_string, max_level, err_msg, clamp=False):
   try:
     level = int(level_string)
-    if clamp:
-      if level > max_level:
-        logger.warning("optimization level '-O" + level_string + "' is not supported; using '-O" + str(max_level) + "' instead")
-        level = max_level
-    assert 0 <= level <= max_level
-  except:
+  except ValueError:
+    raise Exception(err_msg)
+  if clamp:
+    if level > max_level:
+      logger.warning("optimization level '-O" + level_string + "' is not supported; using '-O" + str(max_level) + "' instead")
+      level = max_level
+  if not 0 <= level <= max_level:
     raise Exception(err_msg)
   return level
 

emlink.py

@@ -18,7 +18,7 @@
 def run():
   try:
     me, main, side, out = sys.argv[:4]
-  except:
+  except ValueError:
     print('usage: emlink.py [main module] [side module] [output name]', file=sys.stderr)
     sys.exit(1)
 

emrun.py

@@ -366,10 +366,10 @@ def kill_browser_process():
       else:
         try:
           subprocess.call(['pkill', processname_killed_atexit])
-        except OSError as e:
+        except OSError:
           try:
             subprocess.call(['killall', processname_killed_atexit])
-          except OSError as e:
+          except OSError:
             loge('Both commands pkill and killall failed to clean up the spawned browser process. Perhaps neither of these utilities is available on your system?')
       delete_emrun_safe_firefox_profile()
     # Clear the process name to represent that the browser is now dead.
@@ -567,7 +567,7 @@ def send_head(self):
 
   def log_request(self, code):
     # Filter out 200 OK messages to remove noise.
-    if code is not 200:
+    if code != 200:
       SimpleHTTPRequestHandler.log_request(self, code)
 
   def log_message(self, format, *args):
@@ -588,7 +588,7 @@ def do_POST(self):
       dump_out_directory = 'dump_out'
       try:
         os.mkdir(dump_out_directory)
-      except:
+      except OSError:
         pass
       filename = os.path.join(dump_out_directory, os.path.normpath(filename))
       open(filename, 'wb').write(data)
@@ -598,7 +598,7 @@ def do_POST(self):
       system_info = json.loads(get_system_info(format_json=True))
       try:
         browser_info = json.loads(get_browser_info(browser_exe, format_json=True))
-      except:
+      except ValueError:
         browser_info = ''
       data = {'system': system_info, 'browser': browser_info}
       self.send_response(200)
@@ -630,7 +630,7 @@ def do_POST(self):
           i = data.index('^', 5)
           seq_num = int(data[5:i])
           data = data[i + 1:]
-        except:
+        except ValueError:
           pass
 
       is_exit = data.startswith('^exit^')
@@ -735,7 +735,7 @@ def find_gpu_model(model):
 
   try:
     import_win32api_modules()
-  except:
+  except Exception:
     return []
 
   for i in range(0, 16):
@@ -760,13 +760,13 @@ def find_gpu_model(model):
       try:
         driverVersion = winreg.QueryValueEx(hVideoCardReg, 'DriverVersion')[0]
         VideoCardDescription += ', driver version ' + driverVersion
-      except:
+      except WindowsError:
         pass
 
       try:
         driverDate = winreg.QueryValueEx(hVideoCardReg, 'DriverDate')[0]
         VideoCardDescription += ' (' + driverDate + ')'
-      except:
+      except WindowsError:
         pass
 
       VideoCardMemorySize = winreg.QueryValueEx(hVideoCardReg, 'HardwareInformation.MemorySize')[0]
@@ -831,7 +831,7 @@ def macos_get_gpu_info():
       memory = int(re.search("VRAM (.*?): (.*) MB", gpu).group(2).strip())
       gpus += [{'model': model_name + ' (' + bus + ')', 'ram': memory * 1024 * 1024}]
     return gpus
-  except:
+  except Exception:
     pass
 
 
@@ -941,7 +941,7 @@ def win_get_file_properties(fname):
       strInfo[propName] = win32api.GetFileVersionInfo(fname, strInfoPath)
 
     props['StringFileInfo'] = strInfo
-  except:
+  except Exception:
     pass
 
   return props
@@ -954,7 +954,7 @@ def get_computer_model():
         with open(os.path.join(os.getenv("HOME"), '.emrun.hwmodel.cached'), 'r') as f:
           model = f.read()
           return model
-      except:
+      except IOError:
         pass
 
       try:
@@ -969,7 +969,7 @@ def get_computer_model():
         model = model.group(1).strip()
         open(os.path.join(os.getenv("HOME"), '.emrun.hwmodel.cached'), 'w').write(model) # Cache the hardware model to disk
         return model
-      except:
+      except Exception:
         hwmodel = check_output(['sysctl', 'hw.model'])
         hwmodel = re.search('hw.model: (.*)', hwmodel).group(1).strip()
         return hwmodel
@@ -1006,15 +1006,15 @@ def get_os_version():
       version = ''
       try:
         version = ' ' + check_output(['wmic', 'os', 'get', 'version']).split('\n')[1].strip()
-      except:
+      except Exception:
         pass
       return productName[0] + version + bitness
     elif MACOS:
       return 'macOS ' + platform.mac_ver()[0] + bitness
     elif LINUX:
       kernel_version = check_output(['uname', '-r']).strip()
       return ' '.join(platform.linux_distribution()) + ', linux kernel ' + kernel_version + ' ' + platform.architecture()[0] + bitness
-  except:
+  except Exception:
     return 'Unknown OS'
 
 
@@ -1037,7 +1037,7 @@ def get_system_memory():
       return win32api.GlobalMemoryStatusEx()['TotalPhys']
     elif MACOS:
       return int(check_output(['sysctl', '-n', 'hw.memsize']).strip())
-  except:
+  except Exception:
     return -1
 
 
@@ -1292,7 +1292,7 @@ def get_system_info(format_json):
   else:
     try:
       unique_system_id = open(os.path.expanduser('~/.emrun.generated.guid'), 'r').read().strip()
-    except:
+    except Exception:
       import uuid
       unique_system_id = str(uuid.uuid4())
       try:

emscripten.py

@@ -145,7 +145,7 @@ def parse_fastcomp_output(backend_output, DEBUG):
 
   try:
     metadata = json.loads(metadata_raw, object_pairs_hook=OrderedDict)
-  except:
+  except ValueError:
     logger.error('emscript: failure to parse metadata output from compiler backend. raw output is: \n' + metadata_raw)
     raise
 
@@ -344,7 +344,7 @@ def move_preasm(m):
   # calculate globals
   try:
     del forwarded_json['Variables']['globals']['_llvm_global_ctors'] # not a true variable
-  except:
+  except KeyError:
     pass
   if not shared.Settings.RELOCATABLE:
     global_vars = metadata['externs']
@@ -450,7 +450,7 @@ def collapse_redundant_vars(code):
   old_code = ''
   while code != old_code: # Repeated vars overlap, so can't run in one regex pass. Runs in O(log(N)) time
     old_code = code
-    code = re.sub('(var [^;]*);\s*var ', r'\1,\n  ', code)
+    code = re.sub(r'(var [^;]*);\s*var ', r'\1,\n  ', code)
   return code
 
 
@@ -631,7 +631,7 @@ def is_int(x):
   try:
     int(x)
     return True
-  except:
+  except ValueError:
     return False
 
 
@@ -2211,7 +2211,7 @@ def emscript_wasm_backend(infile, outfile, memfile, libraries, compiler_engine,
 
   try:
     del forwarded_json['Variables']['globals']['_llvm_global_ctors'] # not a true variable
-  except:
+  except KeyError:
     pass
 
   sending = create_sending_wasm(invoke_funcs, forwarded_json, metadata)

site/source/get_api_items.py

@@ -46,7 +46,7 @@ def addapiitems(matchobj):
         api_item = api_item.split('(')[0]
         try:
             api_item = api_item.split(' ')[1]
-        except:
+        except IndexError:
             pass
 
         # print lang

site/source/get_wiki.py

@@ -57,7 +57,7 @@ def errorhandler(func, path, exc_info):
     try:
         shutil.rmtree(output_dir, ignore_errors=False, onerror=errorhandler)
         print('Old wiki clone removed')
-    except:
+    except IOError:
         print('No directory to clean found')
 
 
@@ -72,7 +72,7 @@ def CloneWiki():
     try:
         os.makedirs(output_dir)
         print('Created directory')
-    except:
+    except OSError:
         pass
 
     # Clone

tests/fuzz/creduce_tester.py

@@ -52,7 +52,7 @@ def try_js(args):
   try:
     try_js(args)
     break
-  except Exception as e:
+  except Exception:
     pass
 else:
   sys.exit(0)

tests/fuzz/csmith_driver.py

@@ -82,7 +82,7 @@
   shared.try_delete(filename)
   try:
     shared.run_process([COMP, '-m32', opts, fullname, '-o', filename + '1'] + CSMITH_CFLAGS + ['-w']) # + shared.EMSDK_OPTS
-  except CalledProcessError as e:
+  except CalledProcessError:
     print('Failed to compile natively using clang')
     notes['invalid'] += 1
     continue

tests/runner.py

@@ -651,7 +651,7 @@ def build(self, src, dirname, filename, main_file=None,
         try:
           # Make sure we notice if compilation steps failed
           os.remove(f + '.o')
-        except:
+        except OSError:
           pass
         args = [PYTHON, EMCC] + self.get_emcc_args(main_file=True) + \
                ['-I' + dirname, '-I' + os.path.join(dirname, 'include')] + \
@@ -1660,7 +1660,7 @@ def build_library(name,
         stderr = None
       try:
         Building.configure(configure + configure_args, env=env, stdout=stdout, stderr=stderr)
-      except subprocess.CalledProcessError as e:
+      except subprocess.CalledProcessError:
         pass # Ignore exit code != 0
 
     def open_make_out(mode='r'):
@@ -1765,7 +1765,7 @@ def skip_requested_tests(args, modules):
             suite = getattr(m, suite_name)
             setattr(suite, test_name, lambda s: s.skipTest("requested to be skipped"))
             break
-          except:
+          except AttributeError:
             pass
       args[i] = None
   return [a for a in args if a is not None]