This is a bit of a weird question, but I only ask on SO because of this post.
Some Context
I'm refactoring and thought it'd be great utility if I could merge two JavaScript files. One file is original and the other has a few tiny changes - though the process of manually editing takes time and can cause potential unexpected issues in the future. It's annoyingly repetitive.
One solution I considered was a text templating system, where exterior variables are presented and the output is changed when served to the client (it's run through a CDN). For instance, instead of having two different files with minute changes such as:
const MAXIMUM = 5;
and
const MAXIMUM = 100;
It could be done like:
<% if (type === "capped") { %>
const MAXIMUM = 5;
<% } else { %>
const MAXIMUM = 100;
<% } %>
But, my Atom grammar for JavaScript would mess up and ruin the rest of my file. In the last example presented, I'd wish to be able to stop the Grammar from interpreting line 1, 3 and 5.
Simply: is it possible to exclude certain lines of JavaScript from being interpreted by Atom's currently-selected Grammar.
Related
Right or wrong: In Cypress, its impossible to read a value on page X, then keep this value and compare it to a value on page Y.
I can read a value from the page and log it:
cy.get('[data-e2e-selector=whatever]').then(elm => cy.log('Value from page X : ' + elm))
or, for instance, the number of elements with similar or partially matchin selectors:
cy.get('[data-e2e-selector=^whatever]').then(elm => cy.log('Number of elements like this on page X: ' + elm.length))
Hoever, I cannot create a variable of this, because of the asynchronous way Cypress runs. Right? Any value created to just be blank.
Nor can I pass the value read to a method, which in turn compares it to the value on the next page:
compareToValueOnNextPage(cy.get('[data-e2e-selector=^whatever]').then(elm => elm.length));
compareToValueOnNextPage(value: number) { // NB: Not sure if it's a number or string yet...
cy.get('[data-e2e-selector=^whateverNextPage]').then(elm => elm.length).should('have.length', 4)
}
Basically, if I want to compare values, the either have to be on the same page, or they need to be hard-coded. This is a huge limitation when actually end-to-end testing some applications. Very often, a value is created on page X, based on input which should in many cases ba random, thus creating a dynamic value in the test. Then, on page Y, that same value is fetch (from the backend) or shown in some other way, in a Summary etc. And, naturally, I want to compare the value shown on page X to the one shown on page Y/Summary. But this is not possible, due to the very unit-testing thinking that seems to be the foundation for Cypress.
Or am I missing something here? Are there ways around this that aren't ugly/smelly? I think it's possible to store the value on page X in a file, then read that file on page Y. However, Cypress seems to only have one option when reading the file, and that's reading the whole file and looking for a match. So that file would be a mess. Or I'd need several files.
I realize this is kind of trying to impose non-functional ways on a quite functional and asynchroeous technology. However, if it's not possible to "keep" a value and use it later, it's very limiting when it comes to end-to-end testing (even though it's not when the testing is unit-based on frontend components).
UPDATE:
As per Kerrry's suggestion in the answer below:
cy.get('[data-e2e-selector=dellan-accordion]')
.then(elm => cy.wrap(elm.length).as("myVariableName"));
-GO TO NEXT PAGE-
cy.get('[data-e2e-selector=betalingsplan-dellan]')
.then(elm => elm.length)
.should('have.length', myVariableName)
This yeilds "expected 4 to have property 'length'.
This means, obviously, that I cannot get the length of the length.
So I replace 'have.length' with 'eq':
cy.get('[data-e2e-selector=betalingsplan-dellan]')
.then(elm => elm.length)
.should('have.length', myVariableName)
And I get the following error:
expected 4 to equal 0
So, it seems that the first variable - myVariable - is gone after the first cy.get().
If I do everything inside one get (have another get inside that, where I go to the next page AND get the count of the elements), then it works. But the way Kerry shows it, it would be much more flexible. But, alas, the above error.
As jonrsharpe mentioned in the comments, please read the Cypress document on variables and aliases thoroughly. This is a core concept of Cypress, and it will give you a solid understanding of how to implement variables and carry the values between test steps.
The reader's digest example of what you how you can achieve is this:
cy.get('[data-e2e-selector=^whatever]')
.then(elm => cy.wrap(elm.length).as("myVariableName"));
What this is doing is cy.wrap will yield the value from elm.length in a Cypress command chain, which then allows you to assign it to an alias "myVariableName".
In your following test step where you want to compare the value on a separate page, you would then access the alias' value in one of two ways:
Using this.
cy.get('[data-e2e-selector=^whateverNextPage]')
.then(elm => elm.length)
.should('have.length', this.myVariableName)
OR
via cy.get()
cy.get("#myVariableName").then(function(variableValue){
cy.get('[data-e2e-selector=^whateverNextPage]')
.then(elm => elm.length)
.should('have.length', variableValue)
})
Problem:
My project... printing a sequence of pages... created based on certain templates and database info...
The sequence of pages to be printed can be, in certain situations, of different sizes.
I have been trying to print to real printer, producing multiple pages
if (m_printer->newPage()) { ... }
and on a physical printer, if I try to change the page size, it either doesn't work or puts the printer in an error state.
So there is not much choice, it seems, but to make each page a separate job. Minor disadvantages - possibly on a network. Oh well.
On pdf or any type of file printing, though, it makes a huge difference, whether the sequence is contained in a single document on multiple pages, or if it creates hundreds of different documents of one page each.
So, I found this Is it possible to make a pdf with different page size in Qt?
it seems to be exactly what I need, if I print to a pdf - while for real printer I will make each page a separate job.
The only problem:
How can I tell if I am creating a pdf file, or if I am sending a job to a real printer ?
I looked in QPrinter and QPrinterInfo, I did not see anything that can help.
Pdf printing is probably enabled because of Adobe Acrobat.
I am implementing this currently in Windows.
Edit: why getting the outputFormat (Naidu's answer below) doesn't work:
qprinter.cpp:
void QPrinterPrivate::initEngines(QPrinter::OutputFormat format, const QPrinterInfo &printer)
{
..
// Only set NativeFormat if we have a valid plugin and printer to use
if (format == QPrinter::NativeFormat) { //////// which of course has to be, we have to support any printer
ps = QPlatformPrinterSupportPlugin::get();
QPrinterInfo printerToUse = findValidPrinter(printer);
if (ps && !printerToUse.isNull()) { //////// both valid since the PDF writer is valid
outputFormat = QPrinter::NativeFormat;
printerName = printerToUse.printerName();
}
}
...
}
I would like to have something to check, other than the fact that "pdf" may be contained in the name. If needed, I am willing to use the awful DEVMODE, I just don't know what to look for.
Use the public function
QPrinter::outputFormat()
it returns an enum type enum QPrinter::OutputFormat.
And check if it is QPrinter::PdfFormat
http://doc.qt.io/qt-5/qprinter.html#OutputFormat-enum
Looking for a way to add a custom timestamp(and maybe some extra info) inside a CSS/HTML file everytime you save the file. Is there an extention for brackets, sublime or dreamweaver that does this, Or perhaps some other way to do this?
Thanks
I think this post will give you a Sublime Text plugin that should do what you ask.
In Brackets, you can configure the snippets extension to insert a timestamp manually, like the answer above for Sublime. Here's how: https://stackoverflow.com/a/18844762/1172352.
Similar to the Sublime answer, it would be a bit trickier to do it automatically every time you save. There's not yet a clean hook in Brackets for pre-save processing. Several extensions get around this by listening for a post-save event and saving quickly a second time. You could probably write a timestamp-auto-inserter extension by borrowing their code for that pattern.
Anything that runs automatically would also need a little extra code to find the old timestamp and replace it -- both the snippets solution here and the Sublime solution above just insert the timestamp wherever the cursor/selection is. A regular expression should do the trick for detection.
You'd also want to screen out other file types. Bringing it all together, it would look something like this for Brackets:
function documentSavedHandler(event, doc) {
// TODO: need a little extra code here to ignore save events triggered
// by ourself, to avoid infinite loop
var langId = doc.getLanguage().getId();
if (langId === "html" || langId === "css") {
var pos = /* use regexp to find old timestamp */;
doc.replaceRange(timestampStr, posStart, posEnd);
CommandManager.execute(Commands.FILE_SAVE);
}
}
I'm working in some old code which was originally designed for handling two different kinds of files. I was recently tasked with adding a new kind of file to this code. Most of my problems were solved by filling out an extensive XML file with a new entry that handled everything from what lists were named to how the file is written in plural lower case. But this ended up being insufficient, as there were maybe 50 different places in 24 different code files where I had to update hardcoded switch-statements that only branched for the original two file types.
Unfortunately there is no consistency in this; there are methods which operate half from the XML file, and half off of hardcode. Some of the files which look like they would operate off of the XML file don't, and some that I would expect that I'd need to update the hardcode don't need it. So the only way to find the majority of these is to run through testing the whole system when only part of it is operational, finding that one step to fix (when I'm lucky that error logging actually tells me what is going on), and then running the whole thing again. This wastes time testing the parts of the code which are already confirmed to work, time better spent testing the new parts I have to add on top of it all.
It's a hassle and a half, and to my luck I can expect that I will have to add yet another new kind of file in the near future.
Are there any solutions out there which can aid in this kind of endeavour? Something which I can input some parameters of current features, document what points in a whole code project actually need to be updated, and run something nice the next time I need to add a new feature to the code. It needn't even be fully automated, something that'll help me navigate straight to the specific points in everything and maybe even record what kind of parameters need to be loaded.
Doubt it matters specifically, but the code is comprised of ASP.NET pages, some ASP.NET controls, hundreds of C# code files, and a handful of additional XML files. It's all currently in a couple big Visual Studio 2008 projects.
Not exactly what you are describing, but if you can introduce a seam into the code and lay down some interfaces you can break out and mock, a suite of unit/integration tests would go a long way to helping you modify old code you may not fully understand well.
I completely agree with the comment about using Michael Feathers' book to learn how to wedge new tests into legacy code. I'd also strongly recommend Refactoring, by Martin Fowler. What it sounds like you need to do for your code is to implement the "Replace conditionals with polymorphism" refactoring.
I imagine your code today looks somewhat like this:
if (filetype == 23)
{
type23parser.parse(file);
}
else if (filetype == 69)
{
filestore = type69reader.read(file);
File newfile = convertFSto23(filestore);
type23parser.parse(newfile);
}
What you want to do is to abstract away all the "if (type == foo)" kinds of logic into strategy patterns that are created in a factory.
class FileRules : pReader(NULL), pParser(NULL)
{
private:
FileReaderRules *pReader;
FileParserRules *pParser;
public:
void read(File* inFile) {pReader->read(inFile);};
void parse(File* inFile) {pParser->parse(inFile);};
};
class FileRulesFactory
{
FileRules* GetRules(int inputFiletype, int parserType)
{
switch (inputFiletype)
{
case 23:
pReader = new ASCIIReader;
break;
case 69:
pReader = new EBCDICReader;
break;
}
switch (parserType)
... etc...
then your main line of code looks like this:
FileRules* rules = FileRulesFactory.GetRules(filetype, parsertype);
rules.read(file);
rules.parse(file);
Pull off this refactoring, and adding a new set of file types, parsers, readers, etc., becomes as simple as writing one exclusive to your new type.
Of course, go read the book. I vastly oversimplified it here, and probably got stuff wrong, but you should get the general idea of how to approach it from this. I can also recommend another book, "Head First Design Patterns", which has a great section on the Factory patterns (if you like those "Head First" kinds of books.)
I've 3 .jsp files. index.jsp and sqrtcalculator.jsp and error.jsp.
In index.jsp there's a text field and a button. In sqrtcalculator.jps there's the, well, calculator.
Now, when I leave the field empty and press the button, an expection is called, because the field is empty. And I can then reroute to an individual error.jsp site to display the errors, and exception stack like
<%= request.getAttribute("javax.servlet.error.request_uri") %>
<%= exception.getMessage() %>
<%= exception %>
etc.
Problem is, when I enter -5 in the textfield, I can't get an exception, because Math.sqrt(-5) doesn't return an error but "NaN".
How can I force it to be an exception? The idea is to reroute the user to an individual error.jsp and displaying the errors. But like I said Math.sqrt(-5) doesn't return errors or exceptions but "NaN" textstring.
I don't want something like this just FYI
<%if (NaN){
%>
<p>Nope, Square root from negative numbers is not defined!</p>
<%}
%>
Warning, the test for NaN in the previous answer is wrong (NaN is NOT equal to itself). In Java the better way to test for NaN is
if (Double.isNaN(answer)) {
// throw exception
}
alternatively
if (answer != answer) {
}
While this second version will work, it is sure to puzzle those not aware of the curious behaviour of NaN.
How about:
if (x >= 0.0) {
return Math.sqrt(x);
} else {
throw new ArithmeticException("Square root from negative numbers is not defined!");
}
Note that ArithmeticException is a subclass of RuntimeException and therefore does not need to be declared in the throws clause of your function.
It's presumably returning NaN because square roots of negative numbers are indeed defined, they're just not real numbers. Is there any reason you can't do this?
if(Double.isNaN(answer))
throw new ArithmeticException("Answer unreal");
That should tickle your exception handling code, but the source line might just be a few lines off. I've never written JSP, but that makes sense in Java.
I'm not very good in jsp but afaik you should be able to use basic java code.. so i'd check my result for NaN and throw an exception
if (NaN == result)
throw new Exception("NaN");
you'll have to adjust the if ;)
I would ask why you're using scriptlets in JSPs.
If your app really is just three pages (index.jsp and sqrtcalculator.jsp and error.jsp), then maybe it's justifiable.
But my general recommendation would be to stay away from scriptlet code in JSPs and prefer JSTL. Have those calculations done in a server-side component, using a Model-2 MVC arrangement.
If your app really consists of only three pages, re-architecting it to use Model-2 MVC would not be difficult to do. You might find that it's far more extensible that way. If you're unfamiliar with Model-2 MVC you can read about it here. If you're familiar with it, this might be a self-contained problem that's small enough to let you see where it could provide some value in future projects.
Another thought would be to add complex numbers to your calculator, because the square root of negative numbers is indeed a valid concept. It just requires imaginary numbers. Maybe your calculator needs to be extended to maximize usefulness.
I can't seem to get it to work....
if (d < 0){
throw new Exception("Negative Numbers not possible!");
}
d is a double read via d_string = request.getParameter("numberfromtextfield") and converted to double via double d = Double.parseDouble(d_string);.
This is what Eclipse is telling me: http://pastebin.ca/1691409