git: history of a source code line

git is one of those tools that no matter how much you know about it, there is an infinite supply of new things to learn.  Here’s a handy bit I’ve discovered recently, thanks to this StackOverflow comment:

Since Git 1.8.4, git log has -L to view the evolution of a range of lines.

[…]

And you want to know the history of what is now line 155.

Then, use git log. Here, -L 155,155:git-web–browse.sh means “trace the evolution of lines 155 to 155 in the file named git-web–browse.sh“.

Absolutely brilliant!  I used to suffer through this via an iteration of git blame and git show to the point of custom bash scripts.

400,000 GitHub repositories, 1 billion files, 14 terabytes of code: Spaces or Tabs?

Here is an interesting bit of research – do people prefer tabs or spaces when programming the most popular languages?

Tabs or spaces. We are going to parse a billion files among 14 programming languages to decide which one is on top.

The results are not very surprising and somewhat disappointing (for all of us, tab fans):

tabs vs. spaces

As far as PHP goes, I’m sure the choice of spaces has to do with the PSR-2 coding style guide, which states:

Code MUST use 4 spaces for indenting, not tabs.

On a more technical note, I think this is also related to the explosion of editors and IDEs in the recent years, which, as good as they are, aren’t as good as Vim.  Vim allows for a very flexible configuration, where your code can be formatted and re-formatted any way you like, making tabs or spaces a non-issue at all.

Regardless of the results of the study, what’s more interesting is the method and tools used.  I’ve had my eye on the Google Big Query for a while now, but I’m too busy these days to give it a try.  The article gives a few insights, into how awesome the tool is.  1.6 terabytes of data processed in 864.6 seconds:

That query took a relative long time since it involved joining a 190 million rows table with a 70 million rows one, and over 1.6 terabytes of contents. But don’t worry about having to run it, since I left the result publicly available at [fh-bigquery:github_extracts.contents_top_repos_top_langs].

and:

Analyzing each line of 133 GBs of code in 16 seconds? That’s why I love BigQuery.

If you enjoyed this article, also have a look at “Analyzing GitHub issues and comments with BigQuery“, which works with a similar-sized data, trying to figure out how to write bug reports and pull request comments, so that they would be acted upon faster.

Page builders and multilingual WordPress websites

WPML.org, the web home of the WordPress Multilingual Plugin runs this blog post about the upcoming support for WordPress page builders.  Apart from the good news themselves, there are some insightful results of the survey that the team did, trying to understand who uses page builders and how.  I found the stats on which page builder solutions people use the most interesting:

q2-which-page-builder

At work we are primarily using Divi (when we are not building our own themes), but we’ve also done a few sites with Enfold.  I’ve also seen Avada in the wild.  But I can’t tell you which ones are better, because when it comes to using page builders, I’m mostly not involved.  These tools are so awesome these days that they can be easily used by a non-technical person.  Which is exactly what we do ;)

StackOverflow: Docker vs. Vagrant, with project authors’ comments

There is this discussion over at StackOverflow: Should I use Vagrant or Docker for creating an isolated environment? It attracted the attention of the authors of both projects (as well as many other smart people).  Read the whole thing for interesting insights into what’s there now and what’s coming.  If you’d rather have a summary, here it is:

The short answer is that if you want to manage machines, you should use Vagrant. And if you want to build and run applications environments, you should use Docker.

3 serious (but common) misconceptions about software testing

QA Symphony looks at 3 serious (but common) misconceptions about software testing:

  1. Testing is a Cost Center
  2. Legacy Tools are Good Enough
  3. Testing Is Easy

These are indeed very common.

Let me just briefly focus on the last one.  Consider how quickly the complexity escalates.  You are a building a simple website – nothing fancy, just some modern design and a few pages of content to represent your company.  Let’s say you have just four pages: front page, about us, services, and contact us.  You can quickly check how these four pages look in your browser.  Easy right?

But wait.  People use different browsers to access the web.  So just checking it in your favorite one is not that enough.  Which browsers should you test for?  Let’s say we take the major ones – Google Chrome, Firefox, Microsoft Internet Explorer, and Safari.  These should about cover us.  Until now, your entire test was 4 page loads.  Now you are multiplying it by 4 browsers.  That’s 16 page loads.  So far so good?

Not really.  Each browser has multiple versions, which render pages differently.  Not everyone is using the latest version.  And new versions are released continuously.  Let’s say you decided to support the latest two major versions of each browser.  So now, that’s each browser times two.  So 4 pages by 8 browser comes up to 32 page loads.

But we were just talking about the desktop browsers.  You do want your site looking good on tablets and mobiles, right?  Of course you do.  What does that mean in terms of testing?  Let’s say we support only iOS and Android – two major platforms, both for mobile and tablets.  And we only support the default browser on each of those.  That adds 4 more browsers.

By the way, when people browse on mobiles and tablets, sometimes they view your page holding a device vertically, and sometimes horizontally.  You should probably test for those things as well.  You know, just to make sure, nothing breaks through to the right, or requires too much scrolling down.

Remember that we are still talking about the simplest of all the websites here.  Nothing fancy.

Let’s throw in an additional language.  Here in Cyprus, for example, most websites are in English and Greek.  Some add Russian.  Some have a few languages.  I’ve worked in the companies supporting over a dozen languages on the website.  Each language means that you need to do more tests.  In each of those browsers and on each of the supported devices.

You get my drift.

Something else.  So far our tests were simple page loads, just to have a quick look whether or not the page looks fine.  What if we have multiple tests per page.  You want the page to look fine.  But you also don’t want to have any syntax or grammar errors in the content.  Especially in those foreign languages, that you don’t speak yourself.  And you want the page to be optimized for search engines.  And you want it to be fast (performance testing).

By now, you’ll probably give and agree that testing is not easy.  Not even for the simplest of sites.  Consider just how much more complicated it can get if your site is slightly more complex than that.

Remember that contact us page.  That thing was just showing the company mailing address and the phone number.  Now you want an integrated Google Map and a contact us form.  Nothing wrong with that, right?

Well.  Google services are banned in many countries.  Will your contact us page still work if the user cannot access the Google Maps service?  You’ll need to test for that.  What about your contact form?  Does it actually work? You can’t be sure from it just appearing on the page.  You need to test it now too.

We are still in the domain of simple websites.  And this is getting too long.  Let me just through a few more things at you:

  • more content (imagine a website with dozens or hundreds of pages … this very blog has almost 10,000 blog posts, which are organized into categories, tags, date archives, etc).
  • more functionality (fancy things, dynamic page loads, form validations, etc)
  • even more functionality (online shop, user-driven content, etc)
  • more integrations with other services (Google, social networks, company CRM/ERP/etc)
  • spreading the site across multiple servers for performance (multiple web servers, caching servers, application servers, database servers, etc)

With each and every bit that you throw into your website, the testing gets exponentially more complex.  You have to consider functionality testing, user interface testing, performance testing, security testing, and so on and so forth.

When you get to all of that, you probably have multiple people working in several teams.  They all need to communicate and coordinate.  Which is another layer of complexity.

I’ll stop here.

Next time you think testing is easy, think again.

Update (September 10, 2016): here are a few more misconceptions, which are as common as the ones above.