4

I use PowerShell's PSReadline-based tab completion and I'm looking to implement the following custom completion behavior:

In a folder I have 

File1.java
File1.class
File2.java
File2.class

If I use tab after java I got a list of the files:

java .\File
File1.java
File1.class
File2.java
File2.class

But I want to use a shortcut so I can scroll through only the .java-files but without the extension shown. I also want to get rid of ".\" in the name.

So if I write java and use tab I want to have 

java File1

And next tab gives 

java File2

And so forth (with tab or some other key).

I also wondering, before compling the java-files I have the folder

File1.java
File2.java

I now want to write javac and use tab so I get

javac File1.java

And tab again gives

javac File2.java

And so forth.

Is this possible?

mklement0
  • 382,024
  • 64
  • 607
  • 775
JDoeDoe
  • 361
  • 1
  • 2
  • 7

1 Answers1

5

Use the Register-ArgumentCompleter cmdlet (PSv5+):

# With `java`, cycle through *.java files, but without the extension.
Register-ArgumentCompleter -Native -CommandName java -ScriptBlock {
    param($wordToComplete)
    (Get-ChildItem $wordToComplete*.java).BaseName
}

# With `javac`, cycle through *.java files, but *with* the extension.
Register-ArgumentCompleter -Native -CommandName javac -ScriptBlock {
    param($wordToComplete)
    (Get-ChildItem $wordToComplete*.java).Name
}

To define an alternative key or chord for invoking completion, use Set-PSReadLineKeyHandler; e.g., to make Ctrl+K invoke completions:

Set-PSReadLineKeyHandler -Key ctrl+k -Function TabCompleteNext
Set-PSReadLineKeyHandler -Key ctrl+shift+k -Function TabCompletePrevious

Note that this affects completion globally - you cannot implement a command-specific completion key that way.

mklement0
  • 382,024
  • 64
  • 607
  • 775
  • Thanks, works great! Is it possible to change the shortcut for this? For instance ALT or CTRL, instead of TAB. – JDoeDoe Mar 01 '19 at 13:37
  • @JDoeDoe: Please see my update, but note that you won't be able to use a modifier key such as ALT or CTRL by itself - you must combine it with a non-modifier key. – mklement0 Mar 01 '19 at 13:46
  • I see! Also, CTRL+K affects all scripts using the function TabCompleteNext? I mean, can you somehow bind CTRL+K so it only invokes with javac and java? – JDoeDoe Mar 01 '19 at 14:02
  • @JDoeDoe: Yes, it affects completion globally; personally, I wouldn't go for a command-specific key - and I wouldn't know how to implement it off the top of my head. If it's important to you, I suggest you ask a new question. – mklement0 Mar 01 '19 at 14:19