# Shared groundwork for the t05xx scripts, sourced after setup.sh from inside
# the trash directory. It locates the shipped extensions and the unit checks
# beside this file, lists the standalone Lua interpreters the checks can run
# under, and offers a probe that asks the Lua inside the cgit binary itself
# whether a module is available to it, since that interpreter can differ from
# every standalone one on the path.

EXTENSIONS_DIRECTORY=$(cd "$TEST_OUTPUT_DIRECTORY/../custom/extensions" && pwd)
EXT_TEST_DIRECTORY=$(cd "$TEST_OUTPUT_DIRECTORY/extensions" && pwd)

# Prints the version an interpreter reports, LuaJIT by its own name rather
# than the 5.1 it is compatible with, or the name it was given when it does
# not run.
lua_version() {
	"$1" -e 'io.write(jit and jit.version or _VERSION)' 2>/dev/null ||
		printf '%s' "$1"
}

# The interpreters on the path whose version the extensions claim, 5.1 to
# 5.5 with LuaJIT counting as 5.1, so no script is failed on a version it
# never claimed to run on. Systems spell a versioned name in one of three
# ways, and a plain lua is usually one of those again, so each version runs
# once, under the first name found for it.
interpreters=
ext_lua_versions=
for ext_lua_bin in luajit lua5.1 lua51 lua-5.1 lua5.2 lua52 lua-5.2 \
	lua5.3 lua53 lua-5.3 lua5.4 lua54 lua-5.4 lua5.5 lua55 lua-5.5 lua
do
	command -v "$ext_lua_bin" >/dev/null 2>&1 || continue
	ext_lua_version=$(lua_version "$ext_lua_bin")
	case "$ext_lua_version" in
	"Lua 5."[1-5]|"LuaJIT 2."*)
		;;
	*)
		continue
		;;
	esac
	case "$ext_lua_versions" in
	*"|$ext_lua_version|"*)
		continue
		;;
	esac
	ext_lua_versions="$ext_lua_versions|$ext_lua_version|"
	interpreters="$interpreters $ext_lua_bin"
done
test -n "$interpreters" ||
	say 'no standalone lua on the path, unit checks skipped'

# Asks whether cgit's own Lua can require every module named, by pointing a
# throwaway commit-filter at the given repository and reading its answer off
# the rendered commit page. Filters need a page to run on, which is why a
# repository has to be handed in. A probe that crashes or answers neither
# way stops the run, since reading it as a missing module would switch the
# tests to the wrong expectations.
cgit_lua_probe() {
	test "$CGIT_HAS_LUA" -eq 1 || return 1
	cgit_lua_probe_gitdir=$1
	shift
	{
		echo "function filter_open(...) end"
		echo "function filter_write(str) end"
		echo "function filter_close()"
		echo "local ok = true"
		for cgit_lua_probe_module in "$@"
		do
			echo "if not pcall(require, '$cgit_lua_probe_module') then"
			echo "ok = false"
			echo "end"
		done
		echo "if ok then html('LUA_PROBE_YES') else html('LUA_PROBE_NO') end"
		echo "return 0"
		echo "end"
	} >lua-probe.lua
	cat >lua-probe-cgitrc <<EOF
virtual-root=/
cache-size=0
repo.url=lua-probe
repo.path=$cgit_lua_probe_gitdir
repo.commit-filter=lua:$PWD/lua-probe.lua
EOF
	CGIT_CONFIG="$PWD/lua-probe-cgitrc" QUERY_STRING="url=lua-probe/commit/" \
		cgit >lua-probe.out 2>lua-probe.err ||
		BAIL_OUT "cgit failed while probing its Lua for $*"
	if grep LUA_PROBE_YES lua-probe.out >/dev/null
	then
		return 0
	elif grep LUA_PROBE_NO lua-probe.out >/dev/null
	then
		return 1
	fi
	BAIL_OUT "probing cgit's Lua for $* gave no answer"
}