Crude (no, really) error-passing mechanism

This serves as a PoC of the error-passing interface between the parser
and the frontend. It's as simple as it can get (there is no 'error
format', just a str).

learnbot_dsl/learnbotCode/LearnBlock.py

@@ -915,13 +915,16 @@ def checkProgramRunning(self):
     def textCodeToPython(self, name_Client):
         textCode = self.ui.textCode.toPlainText()
         try:
-            code = parserLearntBotCodeFromCode(textCode, name_Client)
+            code, errors = parserLearntBotCodeFromCode(textCode, name_Client)
             self.ui.pythonCode.clear()
-            if not code:
+            if errors:
+                errorList = '\n'.join(map(lambda error: '- ' + error, errors))
+                errorMsg = f"Your code is empty or is not correct. The following errors were found:\n\n{errorList}"
+
                 msgBox = QtWidgets.QMessageBox()
                 msgBox.setWindowTitle(self.tr("Warning"))
                 msgBox.setIcon(QtWidgets.QMessageBox.Warning)
-                msgBox.setText(self.tr("Your code is empty or is not correct"))
+                msgBox.setText(self.tr(errorMsg))
                 msgBox.setStandardButtons(QtWidgets.QMessageBox.Ok)
                 msgBox.setDefaultButton(QtWidgets.QMessageBox.Ok)
                 msgBox.exec_()

learnbot_dsl/learnbotCode/Parser.py

@@ -317,6 +317,9 @@ def __parserFromString(text):
 list_when = []
 usedFunctions = []
 
+def __typecheckParseTree():
+    pass
+
 def __generatePy(lines):
     global usedFunctions
     usedFunctions = []
@@ -583,8 +586,11 @@ def parserLearntBotCodeOnlyUserFuntion(code):
 def parserLearntBotCode(inputFile, outputFile, client_name):
     global usedFunctions
 
+    errors = []
+
     try:
         tree = __parserFromFile(inputFile)
+        errors.append("Parse error (somewhere)")
     except Exception as e:
         traceback.print_exc()
         raise e
@@ -600,20 +606,23 @@ def parserLearntBotCode(inputFile, outputFile, client_name):
         with open(outputFile, 'w') as f:
             f.write(header)
             f.write(text)
-        return True
+        return header + text, errors
     else:
-        return False
+        return False, errors
 
 def parserLearntBotCodeFromCode(code, name_client):
     global usedFunctions
 
+    errors = []
+
     try:
         tree = __parserFromString(code)
     except Exception as e:
         traceback.print_exc()
         raise e
     if not tree:
         text = ""
+        errors.append("Parse error (somewhere)")
     else:
         text = elapsedTimeFunction
         text += signalHandlerFunction
@@ -624,9 +633,9 @@ def parserLearntBotCodeFromCode(code, name_client):
         header = cleanCode(_code=header)
 
     if text is not "":
-        return header + text
+        return header + text, errors
     else:
-        return False
+        return False, errors
 
 def cleanCode(_code):
     newcode = _code.replace(" :", ":").replace("  ", " ").replace("\n\n\n", "\n\n")