Add PowerShell autocompletion feature

README.md

@@ -615,7 +615,7 @@ opposed to this idea. Here's what `eval "$(pyenv init -)"` actually does:
 
 2. **Installs autocompletion.** This is entirely optional but pretty
    useful. Sourcing `$(pyenv root)/completions/pyenv.bash` will set that
-   up. There are also completions for Zsh and Fish.
+   up. There are also completions for Zsh, Fish and PowerShell.
 
 3. **Rehashes shims.** From time to time you'll need to rebuild your
    shim files. Doing this on init makes sure everything is up to

completions/pyenv.pwsh

@@ -0,0 +1,17 @@
+$scriptblock = {
+    param($wordToComplete, $commandAst, $cursorPosition)
+        $words = $commandAst.ToString() 
+        if ( $wordToComplete ) {
+          $matches = (($words[0..$cursorPosition] -join '') | Select-String -Pattern "\s+" -AllMatches).Matches
+          if ( $matches ) {
+            $cursorPosition = $matches[-1].Index - 1
+          }
+        }
+        $words = $words[0..$cursorPosition] -join '' -split "\s+"
+        if ( $words.Count -ge 2 ) {
+          pyenv completions $words[1] | where { $_ -match $wordToComplete }
+        } else {
+          pyenv commands | where { $_ -match $wordToComplete }
+        }
+}
+Register-ArgumentCompleter -Native -CommandName pyenv -ScriptBlock $scriptblock

libexec/pyenv-init

@@ -281,7 +281,14 @@ function print_env() {
 function print_completion() {
   completion="${root}/completions/pyenv.${shell}"
   if [ -r "$completion" ]; then
-    echo "source '$completion'"
+    case "$shell" in
+    pwsh )
+      echo "iex (gc $completion -Raw)"
+      ;;
+    * )
+      echo "source '$completion'"
+      ;;
+    esac
   fi
 }
 
@@ -292,7 +299,7 @@ function print_rehash() {
       echo '& pyenv rehash 2>/dev/null'
       ;;
     * )
-    echo 'command pyenv rehash 2>/dev/null'
+      echo 'command pyenv rehash 2>/dev/null'
       ;;
     esac
   fi
@@ -348,7 +355,7 @@ pyenv() {
 EOS
     ;;
   esac
-
+  
   if [ "$shell" != "fish" ] && [ "$shell" != "pwsh" ]; then
     IFS="|"
     cat <<EOS