I have something like:
new Expectations() {{
mock0.f();
mock1.f();
mock0.f();
mock1.f();
mock0.f();
mock1.f();
}};
Is there a way I can use the 'times =' specification? Something like:
new Expectations() {{
{
mock0.f();
mock1.f();
}
times = 3;
}};
I /could/ have a loop in my Expectations, but I really hate cyclomatic complexities greater than one in my unit tests.
Note that I want to keep using strict expectations.
You can use the Expectations constructor which takes a numberOfIterations argument:
new Expectations(3) {{
{
mock0.f();
mock1.f();
}
}};
NonStrictExpectations and Verifications also support it.
Related
AFAIK, first shown here by Vladimir Milosevic
<div
v-for="( id, index, user=usersData[id], doubleId=doubleThat(id) ) in users"
:key="id">
{{ user.name }}, {{ user.age }} years old And DoubleId = {{ doubleId }}
</div>
I expanded his codepen. Looks like you can define several variables local to the loop this way.
Are there any side-effects or risks you see with this technique?
I find this way to be the most convenient and clean out there but since that is apparently not the intended use it may not be future-proof.
EDIT:
Here is another pen which demonstrates the use case better. While here we reference just one computed property in one place, if the number of properties and references grows, it will lead to a verbose code.
In general, I think the clean way to do what you want to do is to bring the data into a format, where you can loop over it without extra steps. This way, you will never need those additional variables in v-for.
The example from your codepen could look like this:
const app = new Vue({
el: '#app',
data: {
years: [2024, 2025, 2120],
usersData: {...}
},
computed: {
// user objects for each year
ageData() {
return Object.fromEntries(this.years.map(year => [year,
Object.values(this.usersData).map(user => this.userInYear(user, year))
] ))
}
},
methods: {
userInYear(user, year){
return {...user, age: user.age + (year - 2023)}
}
},
});
Now you can iterate it without interruption and shenanigans:
<div v-for="(users, year) in ageData" :key="year">
<b>In {{ year }}:</b>
<div v-for="user in users" :key="user.name">
{{ user.name }} will be {{ user.age }} years old.
</div>
</div>
It is easier to read and change, and it has the added benefit that you can inspect ageData in the console.
That said, I think it is very interesting that you can declare additional variables in v-for, I assume it is possible because of the way vue parses and builds expressions from the provided string, I am pretty sure it won't be removed, and if you and the people you work with are comfortable with it (and are prepared to hear the above over and over like just now), by all means, go for it.
Here's my code:
<div v-for="(message) in messages">
<div class="message-divider sticky-top pb-2" data-label="Test"> </div>
...
What I need to achieve is, if current iteration's message.createdAt.seconds differs by day from the previous one to show message-divider element.
So the time format is in seconds like this: 1621515321
How can I achieve this?
You can do variable assignment as part of the template, so you could assign the previous value and compare, but this is not a very good idea. Instead you can use a computed to prepare your array to only have the objects you want, with the data you need. So in this case, you could use a computed to create a new array with objects that have additional flags like className or showDivider etc.
example:
computed:{
messagesClean(){
let lastCreatedAt;
return this.messages.map(message => {
const ret = {
...message,
showDivider: lastCreatedAt + 3600*24 < message.createdAt.seconds // your custom logic here
}
lastCreatedAt = message.createdAt.seconds
return ret
}
}
}
the logic to determine when the divider gets shown is up to you there, I suspect it may be a bit more complicated than differing by a day.
You need something like this:
<div v-if="compEqRef">
OK
</div>
<div v-else >!!OK!!</div>
Here compEqRef could be in computed:
computed: {
compEqRef() {
//do something
}
},
I am building an app using Node.js and Vue.
My DATA for the component is the following:
data() {
return {
campaign: {
buses: [],
weeks: [
{
oneWayBuses: [],
returnBuses: []
}
]
},
busesMap: {
// id is the bus ID. Value is the index in the campaign.buses array.
},
};
},
I fill the buses and weeks array in MOUNTED section in two separate methods after getting the data from the server:
responseForWeeks => {
responseForWeeks.forEach(
week => this.campaign.weeks.push(week);
)
}
responseForBuses => {
responseForBuses.forEach(
bus => this.campaign.buses.push(bus);
// Here I also fill the busesMap to link each week to its bus index in the array of buses
this.busesMap[bus.id] = this.campaign.buses.length - 1;
)
}
So the idea is that my busesMap looks like busesId keys and index values:
busesMap = {
'k3jbjdlkk': 0,
'xjkxh834b': 1,
'hkf37sndd': 2
}
However, when I try to iterate over weeks, v-if does not update so no bus info is shown:
<ul>
<li
v-for="(busId, index) in week.oneWayBuses"
:key="index"
:item="busId"
>
<span v-if="campaign.buses[busesMap.busId]">
<strong>{{ campaign.buses[busesMap.busId].busLabel }}</strong>
leaves on the
<span>{{ campaign.buses[busesMap.busId].oneWayDepartureDate.toDate() | formatDate }}</span>
</span>
</li>
</ul>
On the other side, if I shorten the v-if condition to campaign.buses, then I get into the condition but campaign.buses[busesMap.busId] is still undefined, so I get an ERROR trying to display busLabel and oneWayDepartureDate
I've read vue in depth documentation, but couldn't come up with a resolution.
Any gotchas you can find out?
Try this:
async mounted(){
await responseForWeeks
await responseForBuses
responseForWeeks => {
responseForWeeks.forEach(
week => this.campaign.weeks.push(week);
)
}
// this is partial since it is what you provided
responseForBuses => {
responseForBuses.forEach(
bus => this.campaign.buses.push(bus);
// Here I also fill the busesMap to link each week to its bus index in the array of buses
this.busesMap[bus.id] = this.campaign.buses.length - 1;
)
}
}
Basically you want to make sure that before your component loads your data is in place. You can also create computed properties which will force re rendering if dependencies are changed and they are in the dom.
Actually, the problem was indeed in the HTML.
When trying to access the object keys, better use [] intead of a dot .
Final HTML result would be as follows:
<ul>
<li
v-for="(busId, index) in week.oneWayBuses"
:key="index"
:item="busId"
>
<span v-if="campaign.buses[[busesMap[busId]]]">
<strong>{{ campaign.buses[busesMap[busId]].busLabel }}</strong>
leaves on the
<span>{{ campaign.buses[busesMap[busId]].oneWayDepartureDate.toDate() | formatDate }}</span>
</span>
</li>
</ul>
What was happening is that previously campaign.buses[busesMap.busId] did not exist, thus not rendering anything. Solved to campaign.buses[busesMap[busId]]. Also used claudators for the displayed moustache sintach.
Hope it helps someone else messing with Objects!
Good evening,
My problem is this: I have a loop that displays simple divs.
I have a method that specifies the dimensiosn of my div (mandatory in my case). However, when I call the method a second time by changing the sizes of the divs, it does not work because there is no re-render.
To overcome this, I generate a guid on my: key of v-for with a variable such as:
<div v-for="task in tasks" :key="task.id + guid()">...blabla...</div>
Is it possible to generate this code directly during the loop to avoid concatenation?
<div v-for="(task, maVar=guid()) in tasks" :key="maVar">...blabla...</div>
PS : code for guid() method :
guid() {
return ([1e7] + -1e3 + -4e3 + -8e3 + -1e11).replace(/[018]/g, c =>
(c ^ crypto.getRandomValues(new Uint8Array(1))[0] & 15 >> c / 4).toString(16))
}
Thanks
You could create a computed property that returns an array of task with a guid added, or if you want to leave tasks untouched, return an object containing each task plus a guid,
computed: {
tasksWithGuid: function() {
return this.tasks.map(task => { return {task, key: task.id + guid() } })
}
}
<div v-for="taskWithGuid in tasksWithGuid" :key="taskWithGuid.key">
{{taskWithGuid.task.someProperty}}
</div>
There is a simpler, more concise technique shown below. It avoids polluting the iterated object with a redundant property. It can be used when there is no unique property in the objects you iterate over.
First in your viewmodel add the method to generate a random number (e.g. with Lodash random)
var random = require('lodash.random');
methods: {
random() {
return random(1000);
}
}
Then in your template reveal the index in v-for and randomize it in v-bind:key with your random() method from the viewmodel by concatenation.
<div v-for="(task, index) in tasks" v-bind:key="index + random()">
// Some markup
</div>
This is as clean as easy.
However note this approach would force redrawing each item in the list instead of replacing only items that differ. This will reset previously drawn state (if any) for unchanged items.
I do like this
function randomKey() {
return (new Date()).getTime() + Math.floor(Math.random() * 10000).toString()
}
Say I wanted to have a project, and one-to-many with to-do items, and wanted to re-order the to-do items arbitrarily?
In the past, I've added a numbered order field, and when someone wants to change the order, had to update all the items with their new order numbers. This is probably the worst approach, since it's not atomic & required several updates.
I notice Django has a multi-valued CommaSeparatedIntegerField which could contain the order by storing the ordered keys to the items in the to-do items table right in one field of the project table.
I've pondered a dewey decimal system where if I wanted to take item 3 and put it between 1 and 2 I would change it's order number to 1.5.
Something tells me there's an easier option that I'm missing though...
How would you give order to a one-to-many relationship?
I hate this problem ... and I run into it all the time.
For my most recent Django site we had a Newsletter which contained N Articles and, of course, order was important. I assigned the default order as ascending Article.id, but this failed if Articles were entered in something other than "correct" order.
On the Newsletter change_form.html page I added a little bit of jQuery magic using the Interface plugin (http://interface.eyecon.ro/). I show the titles of the associated Articles and the user can drag them around as they like. There is an onChange handler that recomputes the Article.id's in article_order field.
Enjoy,
Peter
For app=content, model=Newsletter, the following is in
templates/admin/content/newslettter/change_form.html
{% extends 'admin/change_form.html' %}
{% block form_top %}{% endblock %}
{% block extrahead %}{{ block.super }}
<script type="text/javascript" src="/media/js/jquery.js"></script>
<script type="text/javascript" src="/media/js/interface.js"></script>
<script>
$(document).ready(
function () {
$('ol.articles').Sortable(
{
accept : 'sortableitem',
helperclass : 'sorthelper',
activeclass : 'sortableactive',
hoverclass : 'sortablehover',
opacity: 0.8,
fx: 200,
axis: 'vertically',
opacity: 0.4,
revert: true,
trim: 'art_',
onchange:
function(list){
var arts = list[0].o[list[0].id];
var vals = new Array();
var a;
for (a in arts) {
vals[a] = arts[a].replace(/article./, '');
}
$('#id_article_order').attr('value', vals.join(','));
}
});
}
);
</script>
{% endblock %}
{% block after_related_objects %}
{% if original.articles %}
<style>
.sortableitem {
cursor:move;
width: 300px;
list-style-type: none;
}
</style>
<h4>Associated Articles</h4>
<ol class="articles" id="article_list">
{% for art in original.articles %}
<li id="article.{{art.id}}" class="sortableitem">{{art.title}}</li>
{% endfor %}
</ol>
{% endif %}
{% endblock %}
"added a numbered order field" - good.
"update all the items with their new order numbers" - avoidable.
Use numbers with gaps.
Floating point. That way, someone can insert "1.1" between 1 and 2. I find that this works nicely, as most people can understand how the sequencing works. And you don't have to worry too much about how much space to leave -- there's lots and lots of space between each number.
On the initial load, number the articles by the 100 or 1000 or something with space between each one. In this case, you have to guess how many digits to leave for reordering.
A comma-separated position. Initially, they're all (1,0), (2,0), (3,0), etc. But when you want to rearrange things, you might have to introduce (2,1) and (2,2) that go after (2,0) but before (3.0).
This looks kind of complicated, but some people like this kind of complexity. It's essentially the same as floating-point, except the single number is replace by a (whole-number, implicit-fraction) tuple. And this extends to handle hierarchies.
I have had this problem with two projects I've worked on in the last little while. For my example solution I have a "Form" that has many "Variables" assigned to it and the order of the variables on the form needs to be sortable. So I have implemented the following:
models.py
class Form(models.Model):
FormName = models.CharField(verbose_name="Form Name:", max_length=40)
VariableOrder = models.CommaSeparatedIntegerField(default="[]", editable=False)
def __unicode__(self):
return "%s" % (self.FormName)
class Variable(models.Model):
FormID = models.ForeignKey(Form, default=0, editable=False, related_name="Variable")
VarName = models.CharField(max_length=32, verbose_name="Name of variable in the database:")
def __unicode__(self):
return "%s" % self.VarName
The key from above is the VariableOrder CommaSeparatedIntegerField is where we are going to store the order of the Variables on the Form, and we are going to be using it as a python list, which is why the default is [].
For the template I render my Variables in an that we are going to make drag and drop sortable (the list elements I actually use have a ton more CSS related styling and information about the Variable).
<ul id="sortable">
{% for Variable in VarList %}
<li id="{{ Variable.id }}">{{ Variable }}</li>
{% endfor %}
</ul>
Now we are going to make the list drag and drop for the changing of order. For this to work you need to have the AJAX CSRF snippet from Django site in the head
$(function() {
$("#sortable" ).sortable({
placeholder: "ui-state-highlight",
update: function(event, ui){
$.ajax({
type:"POST",
url:"{% url builder.views.variableorder %}",
data: {Order: JSON.stringify($('#sortable').sortable('toArray')) },
success: function(data){
// Do stuff here - I don't do anything.
}
});
}
});
$( "#sortable" ).disableSelection();
});
The important part above is that "update" calls the function every time there is a position change of any of the variables, which sends the AJAX. toArray on sortable along with the JSON stringify gets us sending the top to bottom id's of each variable, which is used by the view as follows. Note: I keep the active Form object as a session variable, but in another case you would just need to call the Form object you were wanting to change the order of.
def variableorder(request):
if request.is_ajax():
Order = request.POST['Order']
updateOrder = request.session['FormID']
updateOrder.VariableOrder = newOrder
updateOrder.save()
request.session['FormID'] = Form.objects.get(id=updateOrder.id)
return HttpResponse("Order changed.")
else:
pass
The key of all of this is that you can use this CommaSeparatedIntegerField as a list by evaluating the string. For example:
Adding a Variable:
aForm = Form.objects.get(id=1)
currentOrder = aForm.VariableOrder
currentOrder = eval(currentOrder)
newVar = Variable(stuff in here)
newVar.save()
currentOrder.append(newVar.id)
aForm.VariableOrder = currentOrder
aForm.save()
Removing a Variable:
aForm = Form.objects.get(id=1)
currentOrder = aForm.VariableOrder
currentOrder = eval(currentOrder)
# Variable ID that we want to delete = 3
currentOrder.remove(3)
aForm.VariableOrder = currentOrder
aForm.save()
Rendering the Variables in Order:
aForm = Form.objects.get(id=1)
currentOrder = aForm.VariableOrder
currentOrder = eval(currentOrder)
VarList = []
for i in currentOrder:
VarList.append(Variable.objects.get(id=i))
This is a rough first draft of what I am going to use, but it is working well for me. The obvious first improvement being the evaluation to python list being a method in the class. eg.
def getVarOrder(self):
return eval(self.VariableOrder)
and then just call Form.getVarOrder() when want to manipulate the list. In any case hopefully this helps out.
JD
I've run into this so many times that I've settled on managing these dynamically in the BL or UI, and then just persisting the ordering to a purpose-built column once the user is happy. SQL is just intentially designed not to handle orderings, and it always fights back.
This is a late answer to the question, but I just wanted to chime in and point out that B-Trees are a great data structure for this sort of thing, especially if your access patterns don't require you to retrieve the entire list at once.
http://en.wikipedia.org/wiki/B-tree