pylint: Enable and fix singleton-comparison warnings

docs/conf.py

@@ -73,7 +73,7 @@ copyright = '2016-2021, Ethereum'
 with open('../CMakeLists.txt', 'r', encoding='utf8') as f:
     version = re.search('PROJECT_VERSION "([^"]+)"', f.read()).group(1)
 # The full version, including alpha/beta/rc tags.
-if os.path.isfile('../prerelease.txt') != True or os.path.getsize('../prerelease.txt') == 0:
+if not os.path.isfile('../prerelease.txt') or os.path.getsize('../prerelease.txt') == 0:
     release = version
 else:
     # This is a prerelease version

scripts/error_codes.py

@@ -18,7 +18,7 @@ def read_file(file_name):
         with open(file_name, "r", encoding="latin-1" if is_latin else ENCODING) as f:
             content = f.read()
     finally:
-        if content == None:
+        if content is None:
             print(f"Error reading: {file_name}")
     return content
 

scripts/pylintrc

@@ -27,7 +27,6 @@ disable=
     pointless-string-statement,
     redefined-builtin,
     redefined-outer-name,
-    singleton-comparison,
     too-few-public-methods,
     too-many-public-methods,
     ungrouped-imports

scripts/splitSources.py

@@ -40,7 +40,7 @@ def writeSourceToFile(lines):
     filePath, srcName = extractSourceName(lines[0])
     # print("sourceName is ", srcName)
     # print("filePath is", filePath)
-    if filePath != False:
+    if filePath:
         os.system("mkdir -p " + filePath)
     with open(srcName, mode='a+', encoding='utf8', newline='') as f:
         createdSources.append(srcName)

test/lsp.py

@@ -50,7 +50,7 @@ class JsonRpcProcess:
         # Note, we should make use of timeout to avoid infinite blocking if nothing is received.
         CONTENT_LENGTH_HEADER = "Content-Length: "
         CONTENT_TYPE_HEADER = "Content-Type: "
-        if self.process.stdout == None:
+        if self.process.stdout is None:
             return None
         message_size = None
         while True:
@@ -84,7 +84,7 @@ class JsonRpcProcess:
         return json_object
 
     def send_message(self, method_name: str, params: Optional[dict]) -> None:
-        if self.process.stdin == None:
+        if self.process.stdin is None:
             return
         message = {
             'jsonrpc': '2.0',
@@ -246,7 +246,7 @@ class SolidityLSPTestSuite: # {{{
                 }
             }
         }
-        if expose_project_root == False:
+        if not expose_project_root:
             params['rootUri'] = None
         lsp.call_method('initialize', params)
         lsp.send_notification('initialized')