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jasmine text verification: How to normalize text?


I have a page with text in different HTML elements and I want a quick way of verifying the text.

Using jasmine and jasmine-query to load HTML and test DOM.

For example, I want to verify text in this HTML

<table id="users">
    <thead>
        <tr>
            <td>user</td>
            <td>permissions</td>
            <td>last seen</td>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>Darren</td>
            <td>testuser,customer</td>
            <td>today</td>
        </tr>
        <tr>
            <td>Hillary</td>
            <td>administrator</td>
            <td>yesterday</td>
        </tr>
    </tbody>
</table>

And let's say I want to verify each row in my table contains the correct text. Jasmine test file:

    it('should find correct text in table', function () {
        expect( $('#users').find('tbody tr').first() ).toContainText('Darren testuser,customer today');
        expect( $('#users').find('tbody tr').last() ).toContainText('Hillary administrator yesterday');

    });

I will get this failure:

Testexample:: should find correct text in table: failed
  Expected '<tr>
                <td>Darren</td>
                <td>testuser,customer</td>
                <td>today</td>
            </tr>' to contain text 'Darren testuser,customer today'. (1)
  Expected '<tr>
                <td>Hillary</td>
                <td>administrator</td>
                <td>yesterday</td>
            </tr>' to contain text 'Hillary administrator yesterday'. (2)
1 spec in 0.283s.
>> 2 failures

The other experiment was to use jQuery.text() to extract, then I still have an error because of all the whitespace:

    it('should find correct text in table with jQuery.text()', function () {
        expect( $('#users').find('tbody tr').first().text() ).toContain('Darren testuser,customer today');
        expect( $('#users').find('tbody tr').last().text()  ).toContain('Hillary administrator yesterday');

    });

Gives this failure:

Testexample::  should find correct text in table with jQuery.text(): failed
  Expected '
                Darren
                testuser,customer
                today
            ' to contain 'Darren testuser,customer today'. (1)
  Expected '
                Hillary
                administrator
                yesterday
            ' to contain 'Hillary administrator yesterday'. (2)
1 spec in 0.291s.
>> 2 failures

Capybara (for ruby) has a way to normalize text so that I can always see a reasonable text representation of my HTML. How would I normalize whitespace in an easy way so that I can make verifications like this?

(I don't expect answers like 'you should not test across html elements'... since this is the premise for the question. Actually I like making assertions across several elements: It's readable, short, and give a quick view if stuff is working. Also really necessary when I am testing from outside-in)


Solution

  • Thanks to Tobias' answer I ended up improving on that and wrote my own custom matcher. Now I can write:

            expect( $('#users').find('tbody tr').first() ).toHaveNormalizedText('Darren testuser,customer today');
    

    Matcher code -- added in the beforeEach() block of my describe() scenario:

            this.addMatchers({
                toHaveNormalizedText: function(expected) {
                    var actualText = $.trim(this.actual.text()).replace(/\s+/g, ' ');
                    var result = actualText === expected;
                    if( result) return result;
                    //rest is only if it fails
                    var notText = this.isNot ? " not" : "";
                    var charcodes = [];
                    for(var i=0; i<actualText.length; i++){
                        charcodes.push(actualText.charCodeAt(i));
                        if(i>23) break;
                    }
                    this.message = function () {return 'Expected "' + actualText + notText + '" to match "'+expected+'"\n\nFirst 25 charcodes:\n'+charcodes;};
                    return result;
                }
            });
    

    A few notes about this. Here is the actual replacement:

    $.trim(this.actual.text()).replace(/\s+/g, ' ');
    

    $.trim() was important for my html structure which did include whitespace in the beginning of the text() string.

    this.message = function () {return 'Expected "' + actualText + notText + '" to match "'+expected+'"\n\nFirst 25 charcodes:\n'+charcodes;};
    

    this.message is jasmine's custom error message. This string outputs strings like this on error:

    failed
      Expected "Darren testuser,customer todaiiy" to match "Darren testuser,customer today"
    
    First 25 charcodes:
    68,97,114,114,101,110,32,116,101,115,116,117,115,101,114,44,99,117,115,116,111,109,101,114,32 (1)
    

    I decided to add the charcodes because at one point I had a problem with charcodes 10 (newline) and 32 (spaces).