Configure type rendering

During a debugging session, PyCharm shows you information about your variables, types, threads, frames, and more. However, you may want to focus on specific runtime details and have the data filtered or rendered in a specific format. In this scenario, PyCharm lets you customize the how the debugger's output appears Debug tool window and the editor.

Type renderers are also used in the Python Console and Jupyter Variable View.

Custom type renderers

PyCharm allows you to provide a custom display format for various types. This can be achieved by using renderers. A renderer is a special expression associated with a particular type, which controls how the instances of this type are displayed during a debugging session.

Renderers support all types including primitives and arrays. Also, renderers disregard all access modifiers, so you can access any field irrespective of whether it is encapsulated.

Renderers are particularly useful when you are working with custom collections, whose contents aren't easily readable, and you need to identify their contents at a glance.

Add a renderer

Right-click any object on the Threads & Variables tab of the Debug tool window and select Customize Data View from the context menu.
The Python Type Renderers page of Settings with a new renderer opens. Configure it as required.
Apply the changes and preview the updates in the Debug tool window and the editor.

Renderer properties

Item	Description
Renderer name	The name of the renderer. This name is used for managing renderers and doesn't affect how actual data is displayed.
Apply renderer to objects of type (fully-qualified name)	The object type to which this renderer applies. Enter the fully qualified name of the class.
When rendering a node	This option determines how an object itself is displayed: Use default renderer: displays the object as it would be displayed without this renderer. Use this option if you want to only customize the way the object's contents are displayed. Use following expression: lets you use the return value of some expression for displaying the object. All method calls and member variable access are relative to the rendered instance. For example, `self.name` will use the value of the `name` parameter for displaying the object.
When expanding a node	This option determines how the contents of an object are displayed when it is expanded. Use default renderer: displays the node children as they would be displayed without this renderer. This is useful if you want to only customize the way the object itself is displayed. Use list of expressions: allows you to specify multiple expressions each providing its own representation of the node's children.
Append default children	Controls whether the fields of the object (that would be normally displayed when no renderer is specified) should appear along with the expression results. This option is only available with Use list of expressions.

Remove a renderer

Right-click anywhere in the Variables tab and select Customize data views.
On the Python Type Renderers tab, select the renderer that you are going to remove and click Delete. Then, apply the changes.

Mute renderers

You can temporarily disable renderers without removing them altogether:

To mute a single renderer, right-click anywhere in the Variables tab and select Customize data views. On the Python Type Renderers tab, clear the box against the renderer you are going to mute and apply the changes.

When required, you can unmute the renderers using the same procedure.

Last modified: 13 November 2024