How can I implement Robot Framework style variables in this nested for loop?

I've seen a lot of "nested" loops for loops in Robot Framework, basically creating a keyword with a For loop inside and then calling that keyword inside another for the loop. I created a binding for the loop using Python 2.7.13, but since it mostly uses Run Keywords syntax, I could not create a variable using Robot Framework style syntax (for example ${variable_name}= My Keyword

). For the record, these are launch keywords in the embedded Robot Framework library, which uses the following syntax:

Run Keywords    Keyword1    arg11   arg12   AND     Keyword2    arg21   arg22

      

Equivalently, it can be written like this:

Run Keywords    Keyword1    arg11   arg12
...     AND     Keyword2    arg21   arg22

      

It usually does not support variables created in it. But I used Run Keywords as part of the inline Loop. Here's the Python code for that keyword.

from robot.libraries.BuiltIn import BuiltIn

class Loops(object):
    def __init__(self):
        self.selenium_lib = BuiltIn().get_library_instance('ExtendedSelenium2Library')
        self.internal_variables = {}

    def for_loop(self, loop_type, start, end, index_var, *keywords):
        #   Format the keywords
        keywords = self._format_loop(*keywords)

        #   Clean out the internal variables from previous iterations
        self.internal_variables = {}

        #   This is the actual looping part
        for loop_iteration in range(int(start), int(end)):
            keyword_set = self._index_var_swap(loop_iteration, index_var, *keywords)
            #   If it a one-keyword list with no arguments, then I can use the fastest possible keyword to run it
            if len(keyword_set) == 1:
                BuiltIn().run_keyword(keyword_set)
            #   If it a one-keyword list with arguments, then I can use a faster keyword to run it
            elif 'AND' not in keyword_set:
                BuiltIn().run_keyword(*keyword_set)
            #   If it a multiple-keyword list, then I have to use Run Keywords
            else:
                BuiltIn().run_keywords(*keyword_set)

    def _format_loop(self, *keywords):
        keywords = list(keywords)   # I need to format the keywords as a list.
        changed = False             # Whether or not I changed anything in the previous iteration.
        index = 0                   # The item index I'm at in the list of keywords
        del_list = []               # The list of items I need to delete
        swap_list = []              # The list of items i need to swap to AND for the use of Run Keywords
        #   For each argument
        for x in keywords:
            #   Format it to a string
            x = str(x)
            #   If the keyword in question happens to be one of the 'Assign Internal Variable' keywords, then I need
            #       to run it now, not later.
            #   By splitting it up, I add a little complexity to the code but speed up execution when you're just
            #       assigning a scalar variable as opposed to having to search through the next few items just to find
            #       what I know is just going to be the next one.
            #   So, if it the simple assignment...
            if x.lower() == 'assign internal variable':
                #   ...run the Assign Internal Variable keyword with the two inputs
                BuiltIn().run_keyword(x, *keywords[int(index)+1:int(index)+3])
            #   If it the more complicated variable...
            elif x.lower() == 'assign internal variable to keyword':
                #   ...initialize variables...
                deliminator_search = 0
                k_check = x
                #   ...search the next few keywords for a deliminator...
                while k_check != '\\' and k_check != '\\\\':
                    deliminator_search = deliminator_search + 1
                    k_check = keywords[int(index)+deliminator_search]
                #   ...and run the Assign Internal Variable to Keyword keyword with the found keyword
                BuiltIn().run_keyword(x, *keywords[int(index)+1:int(index)+2+deliminator_search])

            #   If the previous element was not changed...
            if not changed:
                #   If the current item is not the last one on the list...
                if x != len(keywords) - 1:
                    #   If the current item is a deliminator...
                    if x == '\\':
                        #   If the next item is a deliminator, delete this item and set changed to True
                        if keywords[int(index) + 1] == '\\':
                            del_list.append(index)
                            changed = True
                        #   If the next item is not a deliminator...
                        else:
                            #   If this isn't the first deliminator on the list, swap it to an 'AND'
                            if index != 0:
                                swap_list.append(index)
                                changed = True
                            #   If this deliminator is in position index=0, just delete it
                            else:
                                del_list.append(index)
                                changed = True
                    #   If the current element is not a deliminator, then I don't need to touch anything.
                #   If the current element is the last one, then I don't need to touch anything
            #   If the previous element was changed, then I don't need to "change" this one...
            elif changed:
                changed = False
                #   ...but if it a deliminator then I do need to set it up for the inner for loop it means.
                if keywords[index] == '\\':
                    keywords[index] = '\\\\'
            index = index + 1   # Advance the index

        # These actually do the swapping and deleting
        for thing in swap_list:
            keywords[thing] = 'AND'
        del_list.reverse()
        for item in del_list:
            del keywords[item]

        # I also need to activate my variables for this set of keywords to run.
        keywords = self._activate_variables(*keywords)

        return keywords

    @staticmethod
    def _index_var_swap(loop_iteration, index_var, *keywords):
        #   Format the keywords as a list for iteration
        keywords = list(keywords)
        index = 0
        #   For every line in keywords
        for line in keywords:
            #   Replace all instances of the index_var in the string with the loop iteration as a string
            keywords[index] = str(line).replace(str(index_var), str(loop_iteration))
            index = index + 1
        return keywords

    def assign_internal_variable(self, variable_name, assignment):
        # This keyword works like any other keyword so that it can be activated by BuiltIn.run_keywords
        # The syntax for an internal variable is '{{varName}}' where varName can be anything
        self.internal_variables[variable_name] = assignment

    def assign_internal_variable_to_keyword(self, variable_name, keyword, *assignment):
        # This keyword works like any other keyword so that it can be activated by BuiltIn.run_keywords
        # The syntax for an internal variable is '{{varName}}' where varName can be anything
        self.internal_variables[variable_name] = BuiltIn.run_keyword(keyword, *assignment)

    def _activate_variables(self, *keywords):
        #   Initialize variables
        keywords = list(keywords)   # Cast keywords as a List
        index = 0                   # The index of the keyword I'm looking at

        #   For each keyword
        for keyword in keywords:
            keyword = str(keyword)  # Cast keyword as a String
            assignment = False      # Whether or not the found variable name is in a variable assignment
            for key in self.internal_variables.keys():
                key = str(key)      # Cast key as a String
                #   If I can find the key in the keyword and it not an assignment...
                if keyword.find(key) > -1 and not assignment:
                    #   ...replace the text of the key in the keyword.
                    keywords[index] = keyword.replace(str(key), str(self.internal_variables[key]))
                #   If the keyword I'm looking at is an assignment...
                if keyword.lower() == 'assign internal variable'\
                        and keyword.lower() != 'assign internal variable to keyword':
                    #   ...then my next keyword is going to definitely be a known variable, so I don't want to touch it.
                    assignment = True
                #   If the keyword I'm looking at is not an assignment...
                else:
                    #   ...set assignment to False just in case the previous one happened to be an assignment.
                    assignment = False
            index = index + 1   # Advance the index
        return keywords     # Return the list of keywords to be used in the format loop

      

As you can see, my workaround is to create a new Assign Internal Variable keyword and its partner. Assign an internal variable to a keyword. However, this changes the syntax of the Robot Framework loop too much for my liking and somewhat limited by the fact that internal variables are completely decoupled from external variables. An example of this keyword in action in a Robot Framework test case looks like this:

*** Variables ***
${gold_squadron} =  Gold
${red_squadron} =   Red

*** Test Cases ***
Test For Loop
    For Loop    IN RANGE    0   1   INDEX0
    ...     \\  For Loop    IN RANGE    1   6   INDEX1
    ...     \\  \\  Assign Internal Variable    {{standing_by}}     Standing By Red Leader
    ...     \\  \\  Run Keyword If      INDEX1 == 1     Log to Console  ${red_squadron} Leader Standing By
    ...     \\  \\  Run Keyword Unless  INDEX1 == 1     Log to Console  ${red_squadron} INDEX1 {{standing_by}}
    ...     \\  For Loop    IN RANGE    1   6   INDEX2
    ...     \\  \\  Assign Internal Variable    {{standing_by_2}}   Standing By Gold Leader
    ...     \\  \\  Run Keyword If      INDEX2 == 1     Log to Console  ${gold_squadron} Leader Standing By
    ...     \\  \\  Run Keyword Unless  INDEX2 == 1     Log to Console  ${gold_squadron} INDEX2 {{standing_by_2}}

      

This loop works as intended, assuming you've imported the python Loops.py file correctly as a library. However, the syntax I'm looking for is this:

*** Variables ***
${gold_squadron} =  Gold
${red_squadron} =   Red

*** Test Cases ***
Test For Loop
    For Loop    IN RANGE    0   1   INDEX0
    ...     \\  For Loop    IN RANGE    1   6   INDEX1
    ...     \\  \\  {standing_by}=      Standing By Red Leader
    ...     \\  \\  Run Keyword If      INDEX1 == 1     Log to Console  ${red_squadron} Leader Standing By
    ...     \\  \\  Run Keyword Unless  INDEX1 == 1     Log to Console  ${red_squadron} INDEX1 {{standing_by}}
    ...     \\  For Loop    IN RANGE    1   6   INDEX2
    ...     \\  \\  {standing_by_2}=    Standing By Gold Leader
    ...     \\  \\  Run Keyword If      INDEX2 == 1     Log to Console  ${gold_squadron} Leader Standing By
    ...     \\  \\  Run Keyword Unless  INDEX2 == 1     Log to Console  ${gold_squadron} INDEX2 {{standing_by_2}}

      

For those who don't want to break into the underlying Robot Framework code (not recommended, it's painful), the reason that loops are not usually related in Robot Framework is because, at a basic level, keywords and loops are two completely different objects. Some keywords are coded so that they can use other keywords (for example, "Start Keyword"), but for loops they are not coded that way. If anyone can find a way to change the syntax of my For Loop, this will make the end result more intuitive for use only by those who have just come from Robot Framework.

Just to be clear, if it was not clear from the examples, I CAN use Robot Framework variables from outside the Test Case and For Loop just fine. I am asking to create them in the loop line itself.

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I finally understood. Here's the corrected code.

from robot.libraries.BuiltIn import BuiltIn


class Loops(object):

    def __init__(self):
        self.selenium_lib = BuiltIn().get_library_instance('ExtendedSelenium2Library')
        self.internal_variables = {}

    def for_loop(self, loop_type, start, end, index_var, *keywords):
        #   Format the keywords
    keywords = self._format_loop(*keywords)

        #   Clean out the internal variables from previous iterations
        self.internal_variables = {}

        #   This is the actual looping part
        for loop_iteration in range(int(start), int(end)):
            keyword_set = self._index_var_swap(loop_iteration, index_var, *keywords)
            #   If it a one-keyword list with no arguments, then I can use the fastest possible keyword to run it
            if len(keyword_set) == 1:
                BuiltIn().run_keyword(keyword_set)
            #   If it a one-keyword list with arguments, then I can use a faster keyword to run it
            elif 'AND' not in keyword_set:
                BuiltIn().run_keyword(*keyword_set)
            #   If it a multiple-keyword list, then I have to use Run Keywords
            else:
                BuiltIn().run_keywords(*keyword_set)

    def _format_loop(self, *keywords):
        keywords = list(keywords)   # I need to format the keywords as a list.
        changed = False             # Whether or not I changed anything in the previous iteration.
        index = 0                   # The item index I'm at in the list of keywords
        del_list = []               # The list of items I need to delete
        swap_list = []              # The list of items i need to swap to AND for the use of Run Keywords

        def _new_variable():
            #   Default to a variable declaration of 'name='
            t = 1
            #   If my variable declaration is 'name ='
            if x[-2:] == ' =':
                #   Reflect that in the value of t
                t = 2

            #   Count the number of cells until the end of the line
            length = self._deliminator_search(index, x, *keywords)

            if length == 3 and not BuiltIn().run_keyword_and_return_status("Keyword Should Exist", keywords[index + 1]):
                #   If I'm assigning a value to my variable
                self._assign_internal_variable(x[:-t], str(keywords[index + 1]))

            elif length == 3:
                #   If I'm assigning the result of a keyword without any arguments
                self._assign_internal_variable_to_keyword(keywords[index][:-t], str(keywords[index + 1]))
            else:
                #   If I'm assigning the result of a keyword with arguments
                self._assign_internal_variable_to_keyword(keywords[index][:-t], keywords[index + 1],
                                                          keywords[index + 2:index + (length - 1)])

            #   Add the variable declaration code to the delete list.
            del_list.extend(range(index - 1, index + length))

        #   For each argument
        for x in keywords:
            #   Format it to a string
            x = str(x)
            #   Assign new variables
            if x[-1:] == '=':
                _new_variable()

            #   If the previous element was not changed...
            if not changed:
                #   If the current item is not the last one on the list...
                if x != len(keywords) - 1:
                    #   If the current item is a deliminator...
                    if x == '\\':
                        #   If the next item is a deliminator, delete this item and set changed to True
                        if keywords[int(index) + 1] == '\\':
                            del_list.append(index)
                            changed = True
                        #   If the next item is not a deliminator...
                        else:
                            #   If this isn't the first deliminator on the list, swap it to an 'AND'
                            if index != 0:
                                swap_list.append(index)
                                changed = True
                            #   If this deliminator is in position index=0, just delete it
                            else:
                                del_list.append(index)
                                changed = True
                    #   If the current element is not a deliminator, then I don't need to touch anything.
                #   If the current element is the last one, then I don't need to touch anything
            #   If the previous element was changed, then I don't need to "change" this one...
            elif changed:
                changed = False
                #   ...but if it a deliminator then I do need to set it up for the inner for loop it means.
                if keywords[index] == '\\':
                    keywords[index] = keywords[index]*2
            index = index + 1   # Advance the index

        # These actually do the swapping and deleting
        for thing in swap_list:
            keywords[thing] = 'AND'
        del_list.reverse()
        for item in del_list:
            del keywords[item]

        # I also need to activate my variables for this set of keywords to run.
        keywords = self._activate_variables(*keywords)

        return keywords

    @staticmethod
    def _index_var_swap(loop_iteration, index_var, *keywords):
        #   Format the keywords as a list for iteration
        keywords = list(keywords)
        index = 0
        #   For every line in keywords
        for line in keywords:
            #   Replace all instances of the index_var in the string with the loop iteration as a string
            keywords[index] = str(line).replace(str(index_var), str(loop_iteration))
            index = index + 1
        return keywords

    def _assign_internal_variable(self, variable_name, assignment):
        # This keyword works like any other keyword so that it can be activated by BuiltIn.run_keywords
        self.internal_variables[variable_name] = assignment

    def _assign_internal_variable_to_keyword(self, variable_name, keyword, *arguments):
        # Uses assign_internal_variable to simplify code.
        # BuiltIn().log_to_console(BuiltIn().run_keyword(keyword, *arguments))
        self._assign_internal_variable(variable_name, BuiltIn().run_keyword(keyword, *arguments))
        # BuiltIn().log_to_console(self.internal_variables[variable_name])

    def _activate_variables(self, *keywords):
        #   Initialize variables
        keywords = list(keywords)   # Cast keywords as a List
        index = 0                   # The index of the keyword I'm looking at

        #   For each keyword
        for keyword in keywords:
            keyword = str(keyword)  # Cast keyword as a String
            assignment = False      # Whether or not the found variable name is in a variable assignment
            for key in self.internal_variables.keys():
                key = str(key)      # Cast key as a String
                #   If I can find the key in the keyword and it not an assignment...
                if keyword.find(key) > -1 and not assignment:
                    #   ...replace the text of the key in the keyword.
                    keywords[index] = keyword.replace(str(key), str(self.internal_variables[key]))
                #   If the keyword I'm looking at is an assignment...
                if keyword.lower() == 'assign internal variable'\
                        and keyword.lower() != 'assign internal variable to keyword':
                    #   ...then my next keyword is going to definitely be a known variable, so I don't want to touch it.
                    assignment = True
                #   If the keyword I'm looking at is not an assignment...
                else:
                    #   ...set assignment to False just in case the previous one happened to be an assignment.
                    assignment = False
            index = index + 1   # Advance the index
            #   NOTE: Replaces the EXACT text, even if it in another keyword or variable, so be very careful
        return keywords     # Return the list of keywords to be used in the format loop

    @staticmethod
    def _deliminator_search(start, keyword, *keywords):
        index = 0
        while keyword != '\\' and keyword != '\\\\':
            keyword = keywords[int(start) + index]
            index = index + 1
        return index

      

And here is the code to test it:



*** Variables ***
${blue_squadron} =      Blue
${gold_squadron} =      Gold
${green_squadron} =     Green
${red_squadron} =       Red

*** Test Cases ***
Test For Loop
    For Loop    IN RANGE    0   1   INDEX0
    ...     \\  For Loop    IN RANGE    1   6   INDEX1
    ...     \\  \\  {standing_by}=      standing by
    ...     \\  \\  Run Keyword If      INDEX1 == 1     Log to Console  This is ${red_squadron} Leader standing by
    ...     \\  \\  Run Keyword Unless  INDEX1 == 1     Log to Console  ${red_squadron} INDEX1 {standing_by}
    ...     \\  For Loop    IN RANGE    1   6   INDEX2
    ...     \\  \\  standing_by_2 =     standing by
    ...     \\  \\  Run Keyword If      INDEX2 == 1     Log to Console  This is ${gold_squadron} Leader standing by
    ...     \\  \\  Run Keyword Unless  INDEX2 == 1     Log to Console  ${gold_squadron} INDEX2 standing_by_2
    ...     \\  For Loop    IN RANGE    1   6   INDEX3
    ...     \\  \\  standing_by_3=      Get Blue Squadron
    ...     \\  \\  Run Keyword If      INDEX3 == 1     Log to Console  This is ${blue_squadron} Leader standing by
    ...     \\  \\  Run Keyword Unless  INDEX3 == 1     Log to Console  ${blue_squadron} INDEX3 standing_by_3
    ...     \\  For Loop    IN RANGE    1   6   INDEX4
    ...     \\  \\  standing_by_4 =     Get Green Squadron   null input
    ...     \\  \\  Run Keyword If      INDEX4 == 1     Log to Console  This is ${green_squadron} Leader standing by
    ...     \\  \\  Run Keyword Unless  INDEX4 == 1     Log to Console  ${green_squadron} INDEX4 standing_by_4

*** Keywords ***
Get Blue Squadron
    [Return]    standing by

Get Green Squadron
    [Arguments]     ${null_input}
    [Return]        standing by

      

To add some clarification to this solution, I don't need a variable in a specific format. It might be if you want to clarify that it is your variable that has no ambiguity, but it is not necessary. I would prefer to leave more options in this program.

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