What is the proper context for working with material nodes?

Question

Trying to work with nodes in a ShaderNodeTree on a material I've just created, and I'm getting the dreaded "context is incorrect" error.

Here's some code I successfully ran in the Blender UI:

def test():
    C.window.workspace = D.workspaces['Shading']
    new_material = D.materials.new('color_ramp')
    new_material.use_nodes = True
    C.active_object.data.materials.append(new_material)
    C.window.screen.areas[3].type = 'NODE_EDITOR'
    C.window.screen.areas[3].ui_type = 'ShaderNodeTree'
    spaces = C.window.screen.areas[3].spaces
    return spaces[0]

With an object selected, this correctly switches the window, creates a new material, assigns it to the object, switches the area to the Node Editor, and even has the main node selected in the Node Editor area. Calling data = test() and then calling data returns:

bpy.data.screens['Scripting']...SpaceNodeEditor

and does not allow me to deselect the main node, nor does it allow me to add new nodes. From the code of the poll() function for nodes/node trees, I was able to see the context needs to be in the Node Editor and have a node tree selected. Calling data.node_tree in the UI correctly prints the node_tree, but interestingly enough my program I'm building does not.

Does anyone know the correct context for working with nodes/node trees?

EDIT: I added some print statements to the function to see if I could see what was going wrong with the context. Looks like it isn't changing the Workspace properly, which could I suppose be part of the issue? Even though it's in the Node Editor area...I'm not quite sure.

Answer 1

Similar issue with this thread that has the same unintuitive solution:

area.spaces.active.node_tree = nodes #add this line before the ops statement
bpy.ops.node.select(deselect_all=True)