Feature: Preserve file extension when duplicating files

[Epigene]

VSCode Version: 1.20.1
OS Version: macOS High Sierra 10.13.2
Settings: https://gist.github.com/Epigene/a65bbf5e88d847b5e0622d42019fb678
Wrongly opened issue in VSC repo: microsoft/vscode#44254

Needed behavior:
When duplicating a file it would be nice to have it append the "-copy" just before the file extension.

Current behavior:
Duplication overrides file extension with "-copy".

Discussion:
As can be seen in the example image below, I choose to duplicate a file named "calendar.apib" and the default duplicate file-name is "calendar-copy" where "calendar-copy.apib" would be much more useful.

[mrmlnc]

Hello, @Epigene,

Sorry for delay. By default, the extension remains unchanged.

• Original: index.d.ts
• Popup with input: index.d (.d, because we don't know how many points is an extension)
• Saved file: index.d.ts

But if the extension does not match the original one, it will be changed:

• Original: index.d.ts
• Popup with input: index.d → index.d.ts2
• Saved file: index.d.ts2

Do you want the file extension to be displayed completely always?

[Epigene]

I never realised that is the behaviour. 😅
A config option that toggles whether the file extension is displayed would be nice.

[btisdall]

Hi, thanks for the extension! It looks like duplication doesn't work as expected if the filename contains more than one period (which is not an uncommon idiom in the *nix world).

How to reproduce:

1. Create foo.dev.json
2. Hit Duplicate file or directory – the new filename is displayed as foo-copy (ie minus the .dev.json suffix).
3. Enter foo.test

Expected filename: foo.test.json
Actual filename: foo.test

[notpushkin]

IMO a better option (if possible with Code APIs) would be to preserve extension(s) while selecting the filename part in the prompt, i. e. for file foo.d.ts a prompt [foo].d.ts ([] denoting a selection) is presented, from where user can:

• rename file while keeping extension by just typing new name,
• add a suffix before the extension (→ and type the suffix),
• change the extension (End Ctrl+Backspace and type new extension),
• finally, rename file completely (Ctrl+A and type new filename).

I can work out a PR if this kind of functionality is okay with you.