Add import on file drag/drop

[mjbvz]

Suggestion

From microsoft/vscode#5240

🔍 Search Terms

• drop
• dnd
• import
• require

⭐ Suggestion

When I drag and drop a file from VS Code's explorer into the top of my TypeScript code, it should insert an import statement

For example if I have the workspace:

index.ts
sub/
    other.ts

And I drop other.ts into index.ts, it should insert:

import $1 from './sub/other'; // here $1 is where the cursor should be after the drop

Other cases

• I should be able to drag and drop multiple files to create multiple imports

• Possible: If I drop the file into somewhere else in the file, we should instead insert an import expression

• The added import path should take into account TypeScript's path resolution logic

• This also should apply when copy and pasting a file into the editor

[DanielRosenwasser]

Related is #50187, but I guess is not the same. I suppose this needs a custom TSServer command?

[DanielRosenwasser]

Some things to discuss/test for:

• What happens if the module exports just a default? (I'd argue the import style changes)
• What if the module exports just a default but also some types? (harder, should discuss)
• What if the import already exists in the file?
• What happens if the drop location is not suitable for a top-level import? (do we generate a dynamic import()?)
• What happens if the drop location is in a comment or string-like node?

[DanielRosenwasser]

• Do we do something different if the source file is a .d.ts file?
• Do we do something different if the target file is a .d.ts file?
• Do we do something different if the source file is global vs. a module?
• Do we do something different if the target file is global vs. a module?

[mjbvz]

Followups from today's sync:

• Experiment with adding imports at the drop location vs adding it to top of the file

• See if VS Code needs any UI tweaks to support adding imports at a non-cursor location (such as at the top of the file)

• TS Server can have a single command that VS Code uses to implement both dnd and copy paste of files