dotnet: added shell completion scripts

pkgs/development/compilers/dotnet/common.nix

···
 , runCommand
 , expect
 , curl
+, installShellFiles
 }: type: args: stdenv.mkDerivation (finalAttrs: args // {
   doInstallCheck = true;
 
···
     export DOTNET_CLI_TELEMETRY_OPTOUT=1
     export DOTNET_SKIP_WORKLOAD_INTEGRITY_CHECK=1 # Skip integrity check on first run, which fails due to read-only directory
   '' + args.setupHook or "");
+
+  nativeBuildInputs = (args.nativeBuildInputs or []) ++ [ installShellFiles ];
+
+  postInstall = ''
+    # completions snippets taken from https://learn.microsoft.com/en-us/dotnet/core/tools/enable-tab-autocomplete
+    installShellCompletion --cmd dotnet \
+      --bash ${./completions/dotnet.bash} \
+      --zsh ${./completions/dotnet.zsh} \
+      --fish ${./completions/dotnet.fish}
+  '';
 
 } // lib.optionalAttrs (type == "sdk") {
   passthru = {

pkgs/development/compilers/dotnet/completions/dotnet.bash

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+# bash parameter completion for the dotnet CLI
+
+function _dotnet_bash_complete()
+{
+  local cur="${COMP_WORDS[COMP_CWORD]}" IFS=$'\n' # On Windows you may need to use use IFS=$'\r\n'
+  local candidates
+
+  read -d '' -ra candidates < <(dotnet complete --position "${COMP_POINT}" "${COMP_LINE}" 2>/dev/null)
+
+  read -d '' -ra COMPREPLY < <(compgen -W "${candidates[*]:-}" -- "$cur")
+}
+
+complete -f -F _dotnet_bash_complete dotnet

pkgs/development/compilers/dotnet/completions/dotnet.fish

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+complete -f -c dotnet -a "(dotnet complete (commandline -cp))"

pkgs/development/compilers/dotnet/completions/dotnet.zsh

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+# zsh parameter completion for the dotnet CLI
+
+_dotnet_zsh_complete()
+{
+  local completions=("$(dotnet complete "$words")")
+
+  # If the completion list is empty, just continue with filename selection
+  if [ -z "$completions" ]
+  then
+    _arguments '*::arguments: _normal'
+    return
+  fi
+
+  # This is not a variable assignment, don't remove spaces!
+  _values = "${(ps:\n:)completions}"
+}
+
+compdef _dotnet_zsh_complete dotnet