git pre-commit hook: XamlStyler + git-format-staged

pre-commit-xaml-styler.sh

#!/usr/bin/env bash

# Git pre-commit hook that uses git-format-staged and XamlStyler to format xaml files on commit.
#
# See also:
#     https://github.com/hallettj/git-format-staged
#     https://github.com/Xavalon/XamlStyler
#
# This assumes that XamlStyler was installed as a local tool in the repository.
# See https://github.com/Xavalon/XamlStyler/wiki/Script-Integration for setup instructions.

set -e

XAML_STYLER_CONFIG="tools/xaml-styler/config.json"
GIT_FORMAT_STAGED_PATH="tools/git-format-staged.py"

files=$( ( git diff --cached --name-only --diff-filter=ACM || true ) \
      |  ( grep -i -E '\.xaml$' || true ) )
if [ -z "$files" ]; then
    exit 0
fi

formatter="dotnet xstyler --config \"${XAML_STYLER_CONFIG}\" --file \"{}\" --write-to-stdout"
# At the time of writing XamlStyler.Console targets .NET 6
if ! command -v "dotnet" >/dev/null || ! dotnet --list-runtimes | grep -q "Microsoft.NETCore.App 6."; then
    >&2 echo "Must install .NET 6 (https://dotnet.microsoft.com/en-us/download/dotnet/6.0)"
    exit 1
fi
dotnet tool restore > /dev/null
if ! dotnet tool list --local | grep -q xamlstyler.console; then
    >&2 echo "Failed to install xamlstyler.console"
    exit 1
fi

if [ ! -f "${GIT_FORMAT_STAGED_PATH}" ]; then
    >&2 echo "pre-commit-xaml-styler.sh: Missing git-format-staged.py"
    exit 1
fi

python_exe='python3'
if ! command -v "${python_exe}" >/dev/null 2>&1; then
    python_exe='python'
fi

"${python_exe}" "${GIT_FORMAT_STAGED_PATH}" --formatter "${formatter}" $files