JetBrains PyCharm Blog

Have you ever wanted to develop a Python or Web application for Linux from your laptop running Windows 7 or MAC OS X? To debug or test your application on different operating systems without ever leaving the IDE? Or just to run large applications that you develop as a team on a dedicated provisioned environment, rather than on regular workstations? Guess what: all of this is possible with the remote development features already available in PyCharm.

The central entry point to remote development with PyCharm is the notion of Remote Interpreters.

You can configure PyCharm to use Python interpreter from a remote host and set it as your project interpreter. Then you can configure your run/debug configurations to run, debug or test your applications on the remote host. The remote host can be a physical remote server, a VM or even a virtualenv environment – it doesn’t matter. PyCharm has everything you need to work with all types of remote hosts.

Actually, most of the Remote Development stuff was already available in previous versions of PyCharm and covered in these nice tutorials. But we never stop working on improving your comfort and user experience, so PyCharm 2.7 gets new additional features.

Vagrant integration

Native Vagrant integration is now implemented in PyCharm 2.7+. It is supported via the plugin Vagrant that comes already bundled with PyCharm. Vagrant integration makes it much easier to provision and manage your VMs, connect to them over the SSH and automatically configure a remote interpreter and an FTP deployment, if you run your development environment in a VM using Vagrant. All this without leaving the IDE!

Before you start working with Vagrant, make sure that the Vagrant plugin is enabled (this is the default). Also make sure that Oracle VirtualBox and Vagrant are installed on your machine.

First, open Settings | Project Settings | Vagrant:

Enter appropriate paths for “Vagrant executable” and “Instance folder,” and then add your first Vagrant Box by clicking the Add (green plus) button:

Here, choose a name for your new Vagrant box and provide the Box URL for downloading the template. Click OK to start downloading your VM.

Good! Now, after this step we have VM downloaded and added to our environment:

Next, open Tools | Vagrant. You will see the Vagrant menu node containing different commands, which correspond to the standard Vagrant actions:

First you need to initialize a Vagrantfile for your project. Select “Init in Project Root” in the menu to automatically create the Vagrantfile, and you will be able to see and modify it like any other file within your project.

Now you can start your first VM! To do so, select Tools | Vagrant | Up.
On the bottom of the screen a special console will open showing you the progress and output from Vagrant:

To be able to run your project on the VM or to connect to the VM, you need to configure the remote interpreter.

This is done through Settings | Project Settings | Project Interpreter | Python Interpreters. Click the Add button and select “Remote interpreter.” Here you will get the “Configure Remote Python Interpreter” dialog:

You can fill it manually, as for an arbitrary remote host, or just use “Fill from Vagrant config.” Click it – and voila! All the required fields are filled with your Vagrant box details.

After this step the remote interpreter will be added to your project. You can set it as the default project interpreter as well.

From this point on you can execute your project using the remote interpreter on the VM:

The Vagrant plugin works gracefully with the Vagrantfile. You can manually edit it, and all you need is just to click Tools | Vagrant | Reload for the Vagrant plugin to pick up new settings.

For example you can set up custom path mappings in Vagrantfile:

After the Vagrant Box is reloaded, a mapping will be created and you will see a new shared folder into your project folder.

Integrated SSH console

One of the coolest and most useful features is that you can log in to your remote host via SSH and work in its console without leaving PyCharm. To do that, just select Tools | Run SSH Terminal. A console opens on the bottom with the prompt:

Feel free to discover its usability. You can even launch Vim in it:

As you can see, PyCharm comes with everything but the kitchen sink! So we really hope you’ll enjoy these new enhancements and feel comfortable developing your applications on remote environments. And as always, please report your issues or feature requests to our YouTrack bug-tracker.

Develop with Pleasure!
PyCharm team

PyCharm integration with PEP 8

It is not a secret that readability is one of the key features of Python. Indeed, a high level of readability is at the heart of Python’s design, following the recognized fact that code is read much more often than it is written. Developers always need to share their code, so it is very important for that code to be easily understood by others. And here come different coding style guides and standards. One of them, PEP 8, is the de facto coding style guide for Python.

PyCharm 2.7 takes care of readability and general beauty of your code. Now it supports continuous checking of your code for PEP 8 compliance on the fly, as you type it in the editor. PyCharm highlights any coding style violations and gives you suggestions, which you can apply instantly with the well known PyCharm quick-fixes:

Following PEP 8 is a good practice, although there are some situations where it is desirable to depart from the standard. The PyCharm team respects your freedom of choice, so you can disable specific PEP 8  warnings if you really need to. You can do that with the following quick-fix:

Or you can completely manage your inspections profile with Settings | Project Settings | Inspections:

Automatic imports optimization in PyCharm

Whenever you remove usages, it’s easy to forget to remove the corresponding imports. Now, in addition to standard PEP 8 checks, PyCharm is capable of optimizing imports. You no longer have to stop what you are doing, scroll to the top of the file, find the unused imports, and remove them manually.

This feature formats the existing import statements, reordering them according to PEP 8, and removes unused ones as well. All you need to do is press Ctrl+Alt+O or go to Code|Optimize imports…

It correctly recognizes code in doctests even though it has different context. For example, when performing Optimize imports, PyCharm takes care not to remove imports in doctests in case they are required.

New general editing features in PyCharm

PyCharm 2.7 also includes two minor but neat features:

• Edit | Fill Paragraph allows you to reflow the current string literal, comment or paragraph in a plain text file, so that lines wrap around and don’t exceed the right margin
• Shadowing built-ins is a new inspection that highlights definitions of names that match the names of Python built-in functions:

Unwrap/Remove editing action in PyCharm

Now PyCharm supports the Unwrap/Remove action for Python, which provides a quick way to remove a control statement surrounding a block of code. To unwrap or remove a statement, place the caret on the expression and press Ctrl+Shift+Delete or go to Code | Unwrap/Remove.

PyCharm shows a pop-up window with all actions that are available in the current context:

We’ve also introduced several refactorings and code insight features that you may find interesting. See the What’s new page or these blog posts for more detailed descriptions: Refactoring enhancements in PyCharm 2.7 and Dynamic runtime type inference in PyCharm 2.7.

Develop with Pleasure!
PyCharm team

PyCharm 2.7 now supports the following new refactoring features:

• Extract Parameter
• Extract on substrings
• Create Parameter quick-fix on unresolved reference
• Change Method Signature

The Extract Parameter refactoring allows you to add a new parameter to a function declaration and update the function calls in your project. Use it to put the result of the selected expression into the function argument list.

This feature is available to be performed “in-place” by default, or through a dialog.
To perform “in-place” refactoring, highlight an expression or place the caret on it and press Ctrl+Alt+P:

Before	After

Note: For more details, please see “Extract Parameter” in Help.

As shown in the example above, now PyCharm is capable of performing the extract refactorings on substrings. Now it is possible to use all the extract refactorings, such as extract constant/field/variable/parameter and other, on substrings.  This is supported for:
• parts of strings with no formatting.
• parts of strings with concatenation via “+”.
• parts of strings with “%” - old-style formatting , including “%()”.
• parts of strings with “str.format()” – new-style formatting, including replacement fields.

Here is an example of the extract variable on a substring with the new-style formatting:

In case of an unresolved symbol, you can easily apply the Create Parameter quick-fix for that, making it a parameter of the function.

Before:

After:
Note: For more information on quick-fixes, please refer to “Resolving Problems” in Help.

With Change Method Signature you are able to refactor a signature of the selected method and update its calls in your project.

To try it, in the editor place the caret on a function name and press Ctrl+F6.
Alternatively, select Refactor > Change Signature from the main menu to open the same dialog:

With this dialog you can:
• Change the function name.
• Add new parameters and remove the existing ones. Note that you can also add a parameter using the dedicated Extract Parameter refactoring.
• Reorder parameters.
• Change parameter names.

After applying changes, a new code will be generated with the new signature propagated through the method call hierarchy:

We hope these new refactoring features will improve your user experience with PyCharm.

Develop with pleasure!
JetBrains PyCharm Team