feat(version): add command to automatically detect and setup nvchecker

Introduce a new version subcommand `setup` which does a best effort to
generate the most minimal required .nvchecker.toml file for specific
sources.

It supports a wide range of common sources like:
- Git, GitHub, GitLab, Hackage, NPM, PyPI, RubyGems, CPAN, crates.io

The creation logic is based on matching a domain for a source which is
something predictable and then simply passes an array of the url parts
for every source creator to extract the useful bits out of the url
array.

Component: pkgctl version setup
Co-authored-by: Levente Polyak <anthraxx@archlinux.org>
Signed-off-by: Jelle van der Waa <jelle@archlinux.org>

7 files changed, 693 insertions, 0 deletions

diff --git a/contrib/completion/bash/devtools.in b/contrib/completion/bash/devtools.in
index 11fa234..136c80f 100644
--- a/contrib/completion/bash/devtools.in
+++ b/contrib/completion/bash/devtools.in
@@ -350,6 +350,7 @@ _pkgctl_repo_switch_opts() {
 
 _pkgctl_version_cmds=(
 	check
+	setup
 	upgrade
 )
 
@@ -360,6 +361,17 @@ _pkgctl_version_check_args=(
 
 _pkgctl_version_check_opts() { _filedir -d; }
 
+_pkgctl_version_setup_args=(
+	--prefer-platform-api
+	--url
+	--no-check
+	-f --force
+	-h --help
+)
+
+_pkgctl_version_setup_opts() { _filedir -d; }
+_pkgctl_version_setup_args__url_opts() { :; }
+
 _pkgctl_version_upgrade_args=(
 	-v --verbose
 	-h --help
diff --git a/contrib/completion/zsh/_devtools.in b/contrib/completion/zsh/_devtools.in
index ee6da85..f430dae 100644
--- a/contrib/completion/zsh/_devtools.in
+++ b/contrib/completion/zsh/_devtools.in
@@ -291,6 +291,7 @@ _pkgctl_args=(
 _pkgctl_version_cmds=(
 	"pkgctl version command"
 	"check[Compares local package versions against upstream versions]"
+	"setup[Automatically detect and setup a basic nvchecker config]"
 	"upgrade[Adjust the PKGBUILD to match the latest upstream version]"
 )
 
@@ -300,6 +301,15 @@ _pkgctl_version_check_args=(
 	'*:git_dir:_files -/'
 )
 
+_pkgctl_version_setup_args=(
+	'(-f --force)'{-f,--force}'[Do not prompt before overwriting]'
+	'--prefer-platform-api[Prefer platform specific GitHub/GitLab API for complex cases]'
+	'--url[Derive check target from URL instead of source array]:url:'
+	'--no-check[Do not run version check after setup]'
+	'(-h --help)'{-h,--help}'[Display usage]'
+	'*:git_dir:_files -/'
+)
+
 _pkgctl_version_upgrade_args=(
 	'(-v --verbose)'{-v,--verbose}'[Display results including up-to-date versions]'
 	'(-h --help)'{-h,--help}'[Display usage]'
diff --git a/doc/man/pkgctl-version-setup.1.asciidoc b/doc/man/pkgctl-version-setup.1.asciidoc
new file mode 100644
index 0000000..81ef008
--- /dev/null
+++ b/doc/man/pkgctl-version-setup.1.asciidoc
@@ -0,0 +1,120 @@
+pkgctl-version-setup(1)
+=======================
+
+Name
+----
+pkgctl-version-setup - Automatically detect and setup a basic nvchecker config
+
+Synopsis
+--------
+pkgctl version setup [OPTIONS] [PKGBASE...]
+
+Description
+-----------
+
+This subcommand automates the creation of a basic nvchecker(1) configuration
+file by analyzing the source array specified in the PKGBUILD(1) file of a
+package. This command intelligently detects various platforms and APIs (e.g.,
+GitHub, GitLab, PyPI) used by the package sources and generates a corresponding
+`.nvchecker.toml` configuration based on its best guess.
+
+This is particularly useful for initializing nvchecker(1) settings for a
+package without manually crafting the `.nvchecker.toml` file. It simplifies the
+process of setting up version checks, especially when transitioning a package's
+monitoring from one source platform to another or starting version checks for a
+new package.
+
+If no `PKGBASE` is specified, the command defaults to using the current working
+directory.
+
+To obtain a list of supported sources and their expected URL formats, please
+consult the sources section.
+
+Options
+-------
+
+*-f, --force*::
+	Overwrite existing nvchecker(1) configuration
+
+*--prefer-platform-api*::
+	Prefer platform specific GitHub/GitLab API over git for complex cases
+
+*--url* 'URL'::
+	Derive check target from the given URL instead of the source array entries
+
+
+*--no-check*::
+	Do not run pkgctl-version-check(1) after setup
+
+*-h, --help*::
+	Show a help text
+
+Sources
+-------
+
+Here are the currently supported platforms and sources, along with examples of
+URL formats that enable their automatic detection as specific source types:
+
+*Git*::
+	* https://github.com/example/project
+	* https://gitlab.com/example/group/project
+	* git://git.foobar.org/example
+	* git+https://git.foobar.org/example
+
+*GitHub*::
+	* https://github.com/example/project
+	* https://github.com/example/project/archive/v1.0/project-v1.0.tar.gz
+
+*GitLab*::
+	* https://gitlab.com/example/group/project
+	* https://gitlab.archlinux.org/archlinux/devtools.git
+	* https://gitlab.archlinux.org/archlinux/devtools/-/releases/v1.1.0/downloads/devtools-v1.1.0.tar.gz
+
+*Hackage*::
+	* https://hackage.haskell.org/package/xmonad
+	* https://hackage.haskell.org/package/xmonad-0.18.0/xmonad-0.18.0.tar.gz
+	* https://hackage.haskell.org/packages/archive/xmonad/0.18.0/xmonad-0.18.0.tar.gz
+
+*NPM*::
+	* https://registry.npmjs.org/node-gyp/-/node-gyp-10.0.1.tgz
+	* https://www.npmjs.com/package/node-gyp
+
+*PyPI*::
+	* https://pypi.io/packages/source/p/pyflakes
+	* https://pypi.org/packages/source/b/bleach
+	* https://files.pythonhosted.org/packages/source/p/pyflakes
+	* https://pypi.org/project/SQLAlchemy/
+
+*RubyGems*::
+	* https://rubygems.org/downloads/diff-lcs-1.5.1.gem
+	* https://rubygems.org/gems/diff-lcs
+
+*CPAN*::
+	* https://search.cpan.org/CPAN/authors/id/C/CO/COSIMO/Locale-PO-0.27.tar.gz
+	* https://cpan.metacpan.org/authors/id/C/CO/COSIMO/Locale-PO-0.27.tar.gz
+
+*crates.io*::
+	* https://static.crates.io/crates/shotgun/shotgun-1.0.crate
+	* https://crates.io/api/v1/crates/shotgun/1.0/download
+	* https://crates.io/crates/git-smash
+
+Examples
+--------
+
+*pkgctl version setup*::
+	Detects the source from the current directory's PKGBUILD(1) and
+	sets up a basic `.nvchecker.toml`.
+
+*pkgctl version setup --url https://github.com/example/project*::
+	Generates an `.nvchecker.toml` for the current PKGBUILD(1) but
+	overrides the source URL with the specified GitHub project.
+
+See Also
+--------
+
+pkgctl-version(1)
+pkgctl-version-check(1)
+nvchecker(1)
+PKGBUILD(5)
+
+include::include/footer.asciidoc[]
diff --git a/doc/man/pkgctl-version.1.asciidoc b/doc/man/pkgctl-version.1.asciidoc
index e6e4037..a72173b 100644
--- a/doc/man/pkgctl-version.1.asciidoc
+++ b/doc/man/pkgctl-version.1.asciidoc
@@ -26,6 +26,9 @@ package's pkgbase. The pkgbase section within the `.nvchecker.toml` file
 specifies the source and method for checking the latest version of the
 corresponding package.
 
+Use pkgctl-version-setup(1) to automatically detect and setup a basic nvchecker
+config based on the source array of the package PKGBUILD.
+
 For detailed information on the various configuration options available for the
 `.nvchecker.toml` file, refer to the configuration files section in
 nvchecker(1). This documentation provides insights into the possible
@@ -48,6 +51,9 @@ Subcommands
 pkgctl version check::
 	Compares local package versions against upstream
 
+pkgctl version setup::
+	Automatically detect and setup a basic nvchecker config
+
 pkgctl version upgrade::
 	Adjust the PKGBUILD to match the latest upstream version
 
@@ -55,6 +61,7 @@ See Also
 --------
 
 pkgctl-version-check(1)
+pkgctl-version-setup(1)
 pkgctl-version-upgrade(1)
 
 include::include/footer.asciidoc[]
diff --git a/src/lib/common.sh b/src/lib/common.sh
index ff767c6..00ece97 100644
--- a/src/lib/common.sh
+++ b/src/lib/common.sh
@@ -342,3 +342,9 @@ is_debug_package() {
 	pkgdesc="$(getpkgdesc "${pkgfile}")"
 	[[ ${pkgdesc} == "Detached debugging symbols for "* && ${pkgbase}-debug = "${pkgname}" ]]
 }
+
+join_by() {
+	local IFS="$1"
+	shift
+	echo "$*"
+}
diff --git a/src/lib/version.sh b/src/lib/version.sh
index ac810ae..a18da83 100644
--- a/src/lib/version.sh
+++ b/src/lib/version.sh
@@ -19,6 +19,7 @@ pkgctl_version_usage() {
 
 		COMMANDS
 		    check      Compares local package versions against upstream
+		    setup      Automatically detect and setup a basic nvchecker config
 		    upgrade    Adjust the PKGBUILD to match the latest upstream version
 
 		OPTIONS
@@ -26,6 +27,7 @@ pkgctl_version_usage() {
 
 		EXAMPLES
 		    $ ${COMMAND} check libfoo linux libbar
+		    $ ${COMMAND} setup libfoo
 _EOF_
 }
 
@@ -57,6 +59,14 @@ pkgctl_version() {
 				pkgctl_version_upgrade "$@"
 				exit $?
 				;;
+			setup)
+				_DEVTOOLS_COMMAND+=" $1"
+				shift
+				# shellcheck source=src/lib/version/setup.sh
+				source "${_DEVTOOLS_LIBRARY_DIR}"/lib/version/setup.sh
+				pkgctl_version_setup "$@"
+				exit 0
+				;;
 			*)
 				die "invalid argument: %s" "$1"
 				;;
diff --git a/src/lib/version/setup.sh b/src/lib/version/setup.sh
new file mode 100644
index 0000000..123862c
--- /dev/null
+++ b/src/lib/version/setup.sh
@@ -0,0 +1,528 @@
+#!/bin/bash
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+[[ -z ${DEVTOOLS_INCLUDE_VERSION_SETUP_SH:-} ]] || return 0
+DEVTOOLS_INCLUDE_VERSION_SETUP_SH=1
+
+_DEVTOOLS_LIBRARY_DIR=${_DEVTOOLS_LIBRARY_DIR:-@pkgdatadir@}
+# shellcheck source=src/lib/common.sh
+source "${_DEVTOOLS_LIBRARY_DIR}"/lib/common.sh
+# shellcheck source=src/lib/version/check.sh
+source "${_DEVTOOLS_LIBRARY_DIR}"/lib/version/check.sh
+
+source /usr/share/makepkg/util/message.sh
+source /usr/share/makepkg/util/source.sh
+
+set -eo pipefail
+
+
+pkgctl_version_setup_usage() {
+	local -r COMMAND=${_DEVTOOLS_COMMAND:-${BASH_SOURCE[0]##*/}}
+	cat <<- _EOF_
+		Usage: ${COMMAND} [OPTIONS] [PKGBASE]...
+
+		Automate the creation of a basic nvchecker configuration file by
+		analyzing the source array specified in the PKGBUILD file of a package.
+
+		If no PKGBASE is specified, the command defaults to using the current
+		working directory.
+
+		OPTIONS
+		    -f, --force            Overwrite existing nvchecker configuration
+		    --prefer-platform-api  Prefer platform specific GitHub/GitLab API for complex cases
+		    --url URL              Derive check target from URL instead of source array
+		    --no-check             Do not run version check after setup
+		    -h, --help             Show this help text
+
+		EXAMPLES
+		    $ ${COMMAND} neovim vim
+_EOF_
+}
+
+pkgctl_version_setup() {
+	local pkgbases=()
+	local override_url=
+	local run_check=1
+	local force=0
+	local prefer_platform_api=0
+
+	local path ret
+	local checks=()
+
+	while (( $# )); do
+		case $1 in
+			-h|--help)
+				pkgctl_version_setup_usage
+				exit 0
+				;;
+			-f|--force)
+				force=1
+				shift
+				;;
+			--prefer-platform-api)
+				prefer_platform_api=1
+				shift
+				;;
+			--url)
+				(( $# <= 1 )) && die "missing argument for %s" "$1"
+				override_url=$2
+				shift 2
+				;;
+			--no-check)
+				run_check=0
+				shift
+				;;
+			--)
+				shift
+				break
+				;;
+			-*)
+				die "invalid argument: %s" "$1"
+				;;
+			*)
+				pkgbases=("$@")
+				break
+				;;
+		esac
+	done
+
+	# Check if used without pkgbases in a packaging directory
+	if (( ${#pkgbases[@]} == 0 )); then
+		if [[ -f PKGBUILD ]]; then
+			pkgbases=(".")
+		else
+			pkgctl_version_setup_usage
+			exit 1
+		fi
+	fi
+
+	ret=0
+	for path in "${pkgbases[@]}"; do
+		# skip paths that are not directories
+		if [[ ! -d "${path}" ]]; then
+			continue
+		fi
+
+		pushd "${path}" >/dev/null
+		if nvchecker_setup "${path}" "${force}" "${prefer_platform_api}" "${override_url}"; then
+			checks+=("${path}")
+		else
+			ret=1
+		fi
+		popd >/dev/null
+	done
+
+	# run checks on the setup targets
+	if (( run_check )) && (( ${#checks[@]} >= 1 )); then
+		echo
+		pkgctl_version_check --verbose "${checks[@]}" || true
+	fi
+
+	return $ret
+}
+
+nvchecker_setup() {
+	local path=$1
+	local force=$2
+	local prefer_platform_api=$3
+	local override_url=$4
+	local pkgbase pkgname source source_url proto domain url_parts section body
+
+	if [[ ! -f PKGBUILD ]]; then
+		msg_error "${BOLD}${path}:${ALL_OFF} no PKGBUILD found"
+		return 1
+	fi
+
+	unset body pkgbase pkgname source url
+	# shellcheck source=contrib/makepkg/PKGBUILD.proto
+	if ! . ./PKGBUILD; then
+		msg_error "${BOLD}${path}:${ALL_OFF} failed to source PKGBUILD"
+		return 1
+	fi
+	pkgbase=${pkgbase:-$pkgname}
+
+	# try to guess from url as last try
+	if [[ -n ${url} ]]; then
+		source+=("${url}")
+	fi
+
+	# handle overwrite of existing config
+	if [[ -f .nvchecker.toml ]] && (( ! force )); then
+		msg_warn "${BOLD}${pkgbase}:${ALL_OFF} nvchecker already configured"
+		return 1
+	fi
+
+	# override the source array with a passed URL
+	if [[ -n ${override_url} ]]; then
+		source=("${override_url}")
+	fi
+
+	# skip empty source array
+	if (( ${#source[@]} == 0 )); then
+		msg_error "${BOLD}${pkgbase}:${ALL_OFF} PKGBUILD has no source array"
+		return 1
+	fi
+
+	for source_url in "${source[@]}"; do
+		# Strips out filename::http for example
+		source_url=$(get_url "${source_url}")
+		# discard query fragments
+		source_url=${source_url%\?*}
+		source_url=${source_url%#*}
+
+		# skip patches
+		if [[ ${source_url} == *.patch ]]; then
+			continue
+		fi
+		# skip signatures
+		if [[ ${source_url} == *.asc ]] || [[ ${source_url} == *.sig ]]; then
+			continue
+		fi
+		# skip local files
+		if [[ ${source_url} != *://* ]]; then
+			continue
+		fi
+
+		# split URL segments while avoiding empty element after protocol and newline at the end
+		mapfile -td / url_parts <<< "${source_url/:\/\//\/}/"
+		unset "url_parts[-1]"
+
+		# extract protocol and domain to select the configuration type
+		proto=${url_parts[0]}
+		domain=${url_parts[1]}
+
+		case "${domain}" in
+			gitlab.*)
+				if (( prefer_platform_api )); then
+					body=$(nvchecker_setup_gitlab "${url_parts[@]}")
+				else
+					body=$(nvchecker_setup_git "${url_parts[@]}")
+				fi
+				break
+				;;
+			github.com)
+				if (( prefer_platform_api )); then
+					body=$(nvchecker_setup_github "${url_parts[@]}")
+				else
+					body=$(nvchecker_setup_git "${url_parts[@]}")
+				fi
+				break
+				;;
+			codeberg.org)
+				body=$(nvchecker_setup_git "${url_parts[@]}")
+				break
+				;;
+			pypi.org|pypi.io|files.pythonhosted.org)
+				body=$(nvchecker_setup_pypi "${url_parts[@]}")
+				break
+				;;
+			hackage.haskell.org)
+				body=$(nvchecker_setup_hackage "${url_parts[@]}")
+				break
+				;;
+			registry.npmjs.org|npmjs.com|www.npmjs.com)
+				body=$(nvchecker_setup_npm "${url_parts[@]}")
+				break
+				;;
+			rubygems.org)
+				body=$(nvchecker_setup_rubygems "${url_parts[@]}")
+				break
+				;;
+			*.cpan.org|*.mcpan.org|*.metacpan.org)
+				body=$(nvchecker_setup_cpan "${url_parts[@]}")
+				break
+				;;
+			crates.io|*.crates.io)
+				body=$(nvchecker_setup_crates_io "${url_parts[@]}")
+				break
+				;;
+			*)
+				if [[ ${proto} == git ]] || [[ ${proto} == git+https ]]; then
+					body=$(nvchecker_setup_git "${url_parts[@]}")
+				fi
+				;;
+		esac
+	done
+
+	if [[ -z "${body}" ]]; then
+		msg_error "${BOLD}${pkgbase}:${ALL_OFF} unable to automatically setup nvchecker"
+		return 1
+	fi
+
+	# escape the section if it contains toml subsection chars
+	section="${pkgbase}"
+	if [[ ${section} == *.* ]]; then
+		section="\"${section}\""
+	fi
+
+	msg_success "${BOLD}${pkgbase}:${ALL_OFF} successfully configured nvchecker"
+	cat > .nvchecker.toml << EOF
+[${section}]
+${body}
+EOF
+}
+
+get_git_url_from_parts() {
+	local url_parts=("$@")
+	local proto=${url_parts[0]#*+}
+	local domain=${url_parts[1]}
+	local url
+	url="${proto}://$(join_by / "${url_parts[@]:1}")"
+
+	case "${domain}" in
+		gitlab.*)
+			url=${url%/-/*/*}
+			[[ ${url} != *.git ]] && url+=.git
+			;;
+		github.com|codeberg.org)
+			url="${proto}://$(join_by / "${url_parts[@]:1:3}")"
+			[[ ${url} != *.git ]] && url+=.git
+			;;
+	esac
+
+	printf '%s' "${url}"
+}
+
+# PyPI
+#
+# As Arch python packages don't necessarily match the pypi name, when the
+# provided source url comes from pypi.io or pypi.org try to extract the package
+# name from the (predictable) tarball download url for example:
+#
+# https://pypi.io/packages/source/p/pyflakes/pyflakes-3.1.0.tar.gz
+# https://pypi.io/packages/source/p/pyflakes
+# https://pypi.org/packages/source/b/bleach
+# https://files.pythonhosted.org/packages/source/p/pyflakes
+# https://pypi.org/project/SQLAlchemy/
+nvchecker_setup_pypi() {
+	local url_parts=("$@")
+	local pypi
+
+	if [[ ${url_parts[2]} == packages ]]; then
+		pypi=${url_parts[5]}
+	elif [[ ${url_parts[2]} == project ]]; then
+		pypi=${url_parts[3]}
+	else
+		return 1
+	fi
+
+	cat << EOF
+source = "pypi"
+pypi = "${pypi}"
+EOF
+}
+
+# Git
+#
+# Set up a generic Git source, while removing the proto specific part from makepkg
+#
+# git+https://github.com/prometheus/prometheus.git
+# https://git.foobar.com/some/path/group/project.git
+# https://gitlab.com/sub/group/project/-/archive/8.0.0/packages-8.0.0.tar.gz
+nvchecker_setup_git() {
+	local url_parts=("$@")
+	local url
+	url=$(get_git_url_from_parts "${url_parts[@]}")
+
+	cat << EOF
+source = "git"
+git = "${url}"
+EOF
+
+	# best effort check if the tags are prefixed with v
+	if git_tags_have_version_prefix "${url}"; then
+		echo 'prefix = "v"'
+	fi
+}
+
+git_tags_have_version_prefix() {
+	local url=$1
+	# best effort check if the tags are prefixed with v
+	if ! grep --max-count=1 --quiet --extended-regex 'refs/tags/v[0-9]+[\.0-9]*$' \
+		<(GIT_TERMINAL_PROMPT=0 git ls-remote --quiet --tags "${url}" 2>/dev/null); then
+		return 1
+	fi
+	return 0
+}
+
+# Github
+#
+# We want to know the $org/$project name from the url
+#
+# https://github.com/prometheus/prometheus/archive/v2.49.1.tar.gz
+nvchecker_setup_github() {
+	local url_parts=("$@")
+	local url project
+	if ! url=$(get_git_url_from_parts "${url_parts[@]}"); then
+		return 1
+	fi
+	project=${url#*://*/}
+	project=${project%.git}
+
+	cat << EOF
+source = "github"
+github = "${project}"
+use_max_tag = true
+EOF
+
+	# best effort check if the tags are prefixed with v
+	if git_tags_have_version_prefix "${url}"; then
+		echo 'prefix = "v"'
+	fi
+}
+
+# GitLab
+#
+# We want to know the $org/$project name from the url
+#
+# git+https://gitlab.com/inkscape/inkscape.git#tag=091e20ef0f204eb40ecde54436e1ef934a03d894
+nvchecker_setup_gitlab() {
+	local url_parts=("$@")
+	local url project host
+	if ! url=$(get_git_url_from_parts "${url_parts[@]}"); then
+		return 1
+	fi
+	project=${url#*://*/}
+	project=${project%.git}
+	cat << EOF
+source = "gitlab"
+gitlab = "${project}"
+EOF
+
+	host=${url#*://}
+	host=${host%%/*}
+	if [[ ${host} != gitlab.com ]]; then
+		echo "host = \"${host}\""
+	fi
+
+	echo "use_max_tag = true"
+
+	# best effort check if the tags are prefixed with v
+	if git_tags_have_version_prefix "${url}"; then
+		echo 'prefix = "v"'
+	fi
+}
+
+# Hackage
+#
+# We want to know the project name
+#
+# https://hackage.haskell.org/package/xmonad
+# https://hackage.haskell.org/package/xmonad-0.18.0/xmonad-0.18.0.tar.gz
+# https://hackage.haskell.org/packages/archive/digits/0.3.1/digits-0.3.1.tar.gz
+nvchecker_setup_hackage() {
+	local url_parts=("$@")
+	local hackage
+
+	if [[ ${url_parts[2]} == packages ]]; then
+		hackage=${url_parts[4]}
+	elif [[ ${url_parts[2]} == package ]] && (( ${#url_parts[@]} == 4 )); then
+		hackage=${url_parts[3]}
+	elif [[ ${url_parts[2]} == package ]] && (( ${#url_parts[@]} >= 5 )); then
+		hackage=${url_parts[3]%-*}
+	else
+		return 1
+	fi
+
+	cat << EOF
+source = "hackage"
+hackage = "${hackage}"
+EOF
+}
+
+# NPM
+#
+# We want to know the project name
+#
+# https://registry.npmjs.org/eslint_d/-/eslint_d-12.1.0.tgz
+# https://www.npmjs.com/package/node-gyp
+nvchecker_setup_npm() {
+	local url_parts=("$@")
+	local npm
+
+	if [[ ${url_parts[1]} == registry.npmjs.org ]]; then
+		npm=${url_parts[2]}
+	elif [[ ${url_parts[2]} == package ]] && (( ${#url_parts[@]} == 4 )); then
+		npm=${url_parts[3]}
+	else
+		return 1
+	fi
+
+	cat << EOF
+source = "npm"
+npm = "${npm}"
+EOF
+}
+
+# RubyGems
+#
+# We want to know the project name
+#
+# https://rubygems.org/downloads/polyglot-0.3.5.gem
+# https://rubygems.org/gems/diff-lcs
+nvchecker_setup_rubygems() {
+	local url_parts=("$@")
+	local gem
+
+	if [[ ${url_parts[2]} == downloads ]]; then
+		gem=${url_parts[-1]%-*}
+	elif [[ ${url_parts[2]} == gems ]]; then
+		gem=${url_parts[3]}
+	else
+		return 1
+	fi
+
+	cat << EOF
+source = "gems"
+gems = "${gem}"
+EOF
+}
+
+# CPAN
+#
+# We want to know the project name
+#
+# source = https://search.cpan.org/CPAN/authors/id/C/CO/COSIMO/Locale-PO-1.2.3.tar.gz
+nvchecker_setup_cpan() {
+	local url_parts=("$@")
+	local cpan=${url_parts[-1]}
+	cpan=${cpan%-*}
+
+	cat << EOF
+source = "cpan"
+cpan = "${cpan}"
+EOF
+}
+
+# crates.io
+#
+# We want to know the crate name
+#
+# https://crates.io/api/v1/crates/${pkgname}/${pkgver}/download
+# https://static.crates.io/crates/${pkgname}/$pkgname-$pkgver.crate
+# https://crates.io/crates/git-smash
+nvchecker_setup_crates_io() {
+	local url_parts=("$@")
+	local crate
+
+	if [[ ${url_parts[2]} == crates ]]; then
+		crate=${url_parts[3]}
+	elif [[ ${url_parts[4]} == crates ]]; then
+		crate=${url_parts[5]}
+	else
+		return 1
+	fi
+
+
+	for i in "${!url_parts[@]}"; do
+		if [[ ${url_parts[i]} == crates ]]; then
+			crate=${url_parts[(( i + 1 ))]}
+		fi
+	done
+
+	cat << EOF
+source = "cratesio"
+cratesio = "${crate}"
+EOF
+}