Search Help general improvements

[otaviomalvess]

1. Search class stuff with a dot (.)

Allow to filter a class properties, methods and others by typing the class name followed by a dot.

A summary of the class stuff would be presented if nothing was provided after the dot. Like so:

Filter: CollisionShape2D.

Results (not putting everything here to not consume too much space):

> CollisionShape2D
    - debug_color             Property
    - disabled                Property
    ... (other properties)
    - debug_color             Method
    - disabled                Method
    - one_way_collision       Method
    ... (other methods)

And when it would be provided:

Filter: CollisionShape2D.disabled

Results:

> CollisionShape2D
    - disabled                Property
    - disabled                Method

I believe this would be particularly helpful when searching with a member only filter. Right now, if I search for "node" with the Signals Only filter, the SceneTree signals appear:

But if I already know the signals belong to the SceneTree, I can't find them when filtering by the class name:

This suggestion is kinda inspired by the behavior on the Project Settings filter:

1	2	3

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2. Autocomplete

I think it's interesting to consider autocompleting to help accelerate the search. When you have a lot of class names starting the same way, it can be cumbersome to do it sometimes.

For example, let's say I want to see the docs for EditorSceneFormatImporterBlend. I understand you could simply type "Blend" but sometimes that's not the way I think. So, I would start searching "EditorSce" and get the following results:

Cool, it's right over there. The easiest and most straightforward way is to append "Blend" at the end of the search. But doing it, doesn't give you anything.

Now I have three options:

1. Erase everything and retype the entire class name;
2. Erase the "Blend" text at the end and manually select the result, or;
3. Realize you can search just for "Blend", erase everything and type it again.

Sometimes, this can be frustrating.

With an autocomplete, it would be something like: "Ed" + tab + "Sc" + tab + "Fo" + tab + "B" + enter.

Now, visually speaking, I understand an autocomplete in a popup like in the code editor could take too much space. So, perhaps consider an inline one like zsh has?

I also believe this would be a good complement for the Search Class Stuff with a Dot suggestion.

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3. Jump Through Resulta

Allow jumping from result to result with a simple combination of key presses, like ctrl + up to move the selection up and ctrl + down to move it down..

For example, the selection could jump from visible_characters_behavior to CharacterBody2D and again to CharacterBody3D by pressing ctrl + down.

I believe this could be reused for the SceneTree?