verifyFunctionWarning.m

function success = verifyFunctionWarning(functionCall, warningMessage, varargin)
% Tests if the warning message fits to the provided warning
%
% USAGE:
%
%    success = verifyFunctionWarning('functionCall', warningMessage, varargin)
%
% INPUTS:
%    functionCall:       The name of a function
%    warningMessage:     The specific warning message that need to be tested
%
% OUPUTS: 
%    success:            Boolean indicating whether the warning message is thrown 
%
% EXAMPLE:
%    % Test whether PaCER function throws the provided warning message: 
%    verifyFunctionWarning('PaCER', warningMessage, 'inputs', {niiCT});
%
% AUTORS:
%    Laurent Heirendt, April 2019
%    Loic Marx, April 2019
%
% NOTE: 
%    This function has been adapted from
%    https://github.com/opencobra/cobratoolbox/blob/master/test/verifyCobraFunctionError.m
%    [5aa9ccd]

    parser = inputParser();
    parser.addRequired('functionCall', @ischar)
    parser.addRequired('warningMessage', @ischar)
    parser.addParamValue('inputs', {}, @iscell)
    parser.addParamValue('outputArgCount', 0, @(x) isnumeric(x) && mod(x,1) == 0);
    parser.parse(functionCall, warningMessage, varargin{:});
    outputArgcount = parser.Results.outputArgCount;

    inputs = parser.Results.inputs;
    functionCall = str2func(functionCall);

    % initialize the test 
    success = false; 

    % create an hidden file 
    logFile = '.testCatch.log'; 
    
    % run the function in diary mode
    diary(logFile);
    try   
        if outputArgcount > 0
            outArgs = cell(outputArgcount, 1);
            [outArgs{:}] = functionCall(inputs{:});
        else
            functionCall(inputs{:});
        end 
    end 
    diary off   
    
    % loop through the temporary diary file
    fid = fopen(logFile);
    tline = fgetl(fid);
    counter = 0;
    
    % read the code until it reaches the end of the script
    while ~feof(fid) 
        % setup the function to read the script three lines by three lines.
        tline = [tline ' ' fgetl(fid)];
        if ~isempty(tline) && contains(tline, warningMessage)
            success = true;
            break;
        end
        
        % if a warning message is found in consecutive three lines, this message will be
        % concatenated in tline. If not, tline will be reset. 
        if counter > 3
            tline = '';
            counter = 0;
        end
        counter = counter + 1;
    end
    fclose(fid);
    
    % remove the temporary diary file
    delete(logFile);
end