RSpec Stubbing: return in a sequence - ruby

I know the following things work:
returning a parameter
subject.should_receive(:get_user_choice){ |choices| choices.to_a[0] }
and a sequence (it will return a 0 on the first call, and the second time "exit")
subject.should_receive(:get_user_choice).and_return(0, "exit")
But how to combine them?
what if I would like to return the parameter the first time and then return "exit"

Alternatively:
subject.should_receive(:get_user_choice).ordered.and_return { |choices| choices.to_a[0] }
subject.should_receive(:get_user_choice).ordered.and_return { "exit" }

Not most elegant, but how about:
n = 0
subject.should_receive(:get_user_choice){|choices|
(n += 1) < 2 ? choices.to_a[0] : "exit"
}

Related

In the following code variable 'checkNumber' is not incrementing to 1 even after 'if' block get executed and so that Break is not working

In the following code variable 'checkNumber' is not incrementing to 1 even after 'if' block get executed and so that Break is not working where i need to break the loop
var checkNumber =0
for (let i = 0; i < totalRowCountAllocPrj; i++){
allocationObjects.getAllocationStatusfromGrid(i).then(text => {
appAllocStatus = Cypress.$(text).text()
cy.log("Allocation Status :" + appAllocStatus)
if(appAllocStatus == userData.approvalReservedAllocStatus){
allocationObjects.getAppAllCheckBoxesfromGrid(i).click()
checkNumber=checkNumber+1
cy.log("index="+i)
}
else{
cy.log("Project is not Reserved")
}
})
cy.log("number="+checkNumber)
if(checkNumber==1)
{
break
}
The variable checkNumber gets incremented inside an asynchronous command, but the loop is running synchronously.
You can't use break but you should be able to stop executing the commands with the inverse check.
Since checkNumber never should go above 0, it's more sensible to use a boolean
let found = 0
for (let i = 0; i < totalRowCountAllocPrj; i++) {
cy.then(() => {
if (!found) {
allocationObjects.getAllocationStatusfromGrid(i).then(text => {
appAllocStatus = Cypress.$(text).text()
if (appAllocStatus === userData.approvalReservedAllocStatus) {
allocationObjects.getAppAllCheckBoxesfromGrid(i).click()
found = true
}
})
}
})
}
BTW you should be able to rewrite allocationObjects.getAllocationStatusfromGrid() to directly search for userData.approvalReservedAllocStatus and get rid of the loop altogether.

How to exit a promise from within a promise?

How do I exit a promise from within a promise? The perl6 docs do not provide an easy method. For example:
my $x = start {
loop { # loop forever until "quit" is seen
my $y = prompt("Say something: ");
if $y ~~ / quit / {
# I want to exit the promise from here;
# "break" and "this.break" are not defined;
# "return" does not break the promise;
# I do NOT want an error exception when exiting a promise;
# I want to return a value as the result of this promise;
}
else { say $y; }
}
}
I do not want to be in the promise loop forever. break() and this.break() are not recognized, and return does not break the promise.
Use the last keyword to quit the loop.
The kept value of a start block is the value returned by its last statement.
So:
my $x = start {
loop { # loop forever until "quit" is seen
my $y = prompt("Say something: ");
if $y ~~ / quit / {
last
}
else { say $y; }
}
42 # <-- The promise will be kept with value `42`
}

go error % not allowed

I have written a program for Mumax with a go syntax but I don't understant my error. Here the script where the error appears :
n:=0
Dtr0:=5*1e-12
Dtd0 :=300*1e-12
Dtf0:=5*1e-12
Dtz0:=20000*1e-12
tr0:=Dtr0
td0:=Dtd0+tr0
tf0:=Dtf0+td0
tz0:=Dtz0+tf0
TT:=tz0
n=t/TT
tr:=tr0+(n*TT)
td:=td0+(n*TT)
tf:=tf0+(n*TT)
tz:=tz0+(n*TT)
if (n % 2 == 0) {
if (n<1 && t<tr) {
a:=(t/tr)
} else if (n>=1 && t>=tz0+((n-1)*TT) && t<tr) {
a:=1/(tr-(tz0+((n-1)*TT)))*(t-(tz0+((n-1)*TT)))
} else if (t>=tr && t<=td) {
a:=1
} else if (t>td && t<=tf) {
a:=(-1/(tf-td))*(t-td)+1
} else if (t>tf && t<tz) {
a:=0
}
}
if (int(n)%2==1) {
if (n<1 && t<tr) {
a:=-(t/tr)
} else if (n>=1.0 && t>=tz0+((n-1)*TT) && t<tr) {
a:=-(1/(tr-(tz0+((n-1)*TT)))*(t-(tz0+((n-1)*TT))))
} else if (t>=tr && t<=td) {
a:=-1
} else if (t>td && t<=tf) {
a:=-((-1/(tf-td))*(t-td)+1)
} else if (t>tf && t<tz) {
a:=0
}
}
And the error message is : line 37: if (n % 2 == 0) {: not allowed: %
Thank's a lot
There are two problems here:
n must be a float because TT must be a float, because that's ultimately a function of two floats. This conflicts with the n := 0 default int definition at the top.
the modulus operator on floats is undefined (see this playground for what happens when you try).
This means you have a very weird Go implementation or we're not seeing everything.
In any case, either you have to either coerce n to an int (as you do in your second if) or use math.Mod somehow.

For loop won't end. Don't know why

I'm writing a for loop for a project that prompts the user to input a number and keeps prompting, continually adding the numbers up. When a string is introduced, the loop should stop. I've done it with a while loop, but the project states that we must do it with a for loop also. The problem is that the prompt keeps running even when 'a = false'. Could someone explain javascript's thinking process? I want to understand why it keeps running back through the loop even though the condition isn't met. Thank you
var addSequence2 = function() {
var total = 0;
var a;
for (; a = true; ) {
var input = prompt("Your current score is " +total+ "\n" + "Next number...");
if (!isNaN(input)) {
a = true;
total = +total + +input;
}
else if (isNaN(input)) {
a = false;
document.write("Your total is " + total);
}
}
};
There is a difference between a = true and a == true.
Your for-loop is basically asking "can I set 'a' to true?", to which the answer is yes, and the loop continues.
Change the condition to a == true (thus asking "Is the value of 'a' true?")
To elaborate, in most programming languages, we distinguish between assignment ("Make 'x' be 4") and testing for equality ("Is 'x' 4?"). By convention (at least in languages that derive their syntax from C), we use '=' to assign/set a value, and '==' to test.
If I'm understanding the specification correctly (no guarantee), what happens here is that the condition condenses as follows:
Is (a = true) true?
Complete the bracket: set a to true
Is (a) true? (we just set it to true, so it must be!)
Try using the equal to operator, i.e. change
for (; a = true; ) {
to
for (; a == true; ) {
You should use a == true instead of a = true......= is an assignment operator
for (; a = true; ), you are assigning the value to the variable "a" and it will always remain true and will end up in infinite loop. In JavaScript it should a===true.
I suspect you want your for to look like this :
for(;a==true;)
as a=true is an assignment, not a comparison.
a == true. The double equal sign compares the two. Single equal assigns the value true to a so this always returns true.
for (; a = true; ) <-- this is an assignation
for (; a == true; ) <-- this should be better
Here's your fixed code :
var addSequence2 = function() {
var total = 0;
var a = true;
for(;Boolean(a);) {
var input = prompt("Your current score is " +total+ "\n" + "Next number...");
if (!isNaN(input)) {
total = total + input;
}
else{
a = false;
document.write("Your total is " + total);
}
}
};

Redundant code constructs

The most egregiously redundant code construct I often see involves using the code sequence
if (condition)
return true;
else
return false;
instead of simply writing
return (condition);
I've seen this beginner error in all sorts of languages: from Pascal and C to PHP and Java. What other such constructs would you flag in a code review?
if (foo == true)
{
do stuff
}
I keep telling the developer that does that that it should be
if ((foo == true) == true)
{
do stuff
}
but he hasn't gotten the hint yet.
if (condition == true)
{
...
}
instead of
if (condition)
{
...
}
Edit:
or even worse and turning around the conditional test:
if (condition == false)
{
...
}
which is easily read as
if (condition) then ...
Using comments instead of source control:
-Commenting out or renaming functions instead of deleting them and trusting that source control can get them back for you if needed.
-Adding comments like "RWF Change" instead of just making the change and letting source control assign the blame.
Somewhere I’ve spotted this thing, which I find to be the pinnacle of boolean redundancy:
return (test == 1)? ((test == 0) ? 0 : 1) : ((test == 0) ? 0 : 1);
:-)
Redundant code is not in itself an error. But if you're really trying to save every character
return (condition);
is redundant too. You can write:
return condition;
Declaring separately from assignment in languages other than C:
int foo;
foo = GetFoo();
Returning uselessly at the end:
// stuff
return;
}
I once had a guy who repeatedly did this:
bool a;
bool b;
...
if (a == true)
b = true;
else
b = false;
void myfunction() {
if(condition) {
// Do some stuff
if(othercond) {
// Do more stuff
}
}
}
instead of
void myfunction() {
if(!condition)
return;
// Do some stuff
if(!othercond)
return;
// Do more stuff
}
Using .tostring on a string
Putting an exit statement as first statement in a function to disable the execution of that function, instead of one of the following options:
Completely removing the function
Commenting the function body
Keeping the function but deleting all the code
Using the exit as first statement makes it very hard to spot, you can easily read over it.
Fear of null (this also can lead to serious problems):
if (name != null)
person.Name = name;
Redundant if's (not using else):
if (!IsPostback)
{
// do something
}
if (IsPostback)
{
// do something else
}
Redundant checks (Split never returns null):
string[] words = sentence.Split(' ');
if (words != null)
More on checks (the second check is redundant if you are going to loop)
if (myArray != null && myArray.Length > 0)
foreach (string s in myArray)
And my favorite for ASP.NET: Scattered DataBinds all over the code in order to make the page render.
Copy paste redundancy:
if (x > 0)
{
// a lot of code to calculate z
y = x + z;
}
else
{
// a lot of code to calculate z
y = x - z;
}
instead of
if (x > 0)
y = x + CalcZ(x);
else
y = x - CalcZ(x);
or even better (or more obfuscated)
y = x + (x > 0 ? 1 : -1) * CalcZ(x)
Allocating elements on the heap instead of the stack.
{
char buff = malloc(1024);
/* ... */
free(buff);
}
instead of
{
char buff[1024];
/* ... */
}
or
{
struct foo *x = (struct foo *)malloc(sizeof(struct foo));
x->a = ...;
bar(x);
free(x);
}
instead of
{
struct foo x;
x.a = ...;
bar(&x);
}
The most common redundant code construct I see is code that is never called from anywhere in the program.
The other is design patterns used where there is no point in using them. For example, writing "new BobFactory().createBob()" everywhere, instead of just writing "new Bob()".
Deleting unused and unnecessary code can massively improve the quality of the system and the team's ability to maintain it. The benefits are often startling to teams who have never considered deleting unnecessary code from their system. I once performed a code review by sitting with a team and deleting over half the code in their project without changing the functionality of their system. I thought they'd be offended but they frequently asked me back for design advice and feedback after that.
I often run into the following:
function foo() {
if ( something ) {
return;
} else {
do_something();
}
}
But it doesn't help telling them that the else is useless here. It has to be either
function foo() {
if ( something ) {
return;
}
do_something();
}
or - depending on the length of checks that are done before do_something():
function foo() {
if ( !something ) {
do_something();
}
}
From nightmarish code reviews.....
char s[100];
followed by
memset(s,0,100);
followed by
s[strlen(s)] = 0;
with lots of nasty
if (strcmp(s, "1") == 0)
littered about the code.
Using an array when you want set behavior. You need to check everything to make sure its not in the array before you insert it, which makes your code longer and slower.
Redundant .ToString() invocations:
const int foo = 5;
Console.WriteLine("Number of Items: " + foo.ToString());
Unnecessary string formatting:
const int foo = 5;
Console.WriteLine("Number of Items: {0}", foo);

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