add luacheck workflow

.github/workflows/luacheck.yml

@@ -0,0 +1,13 @@
+name: luacheck
+on: [push, pull_request]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: apt
+      run: sudo apt-get install -y luarocks
+    - name: luacheck install
+      run: luarocks install --local luacheck
+    - name: luacheck run
+      run: $HOME/.luarocks/bin/luacheck ./

.luacheckrc

@@ -1,14 +1,17 @@
 unused_args = false
 allow_defined_top = true
+max_line_length = 185
 
-read_globals = {
+globals = {
 	"biome_lib",
-	"DIR_DELIM",
-	"minetest", "core",
-	"dump",
-	"vector", "nodeupdate",
-	"VoxelManip", "VoxelArea",
-	"PseudoRandom", "ItemStack",
-	"default",
 }
 
+read_globals = {
+	table = {fields = {"copy"}},
+
+	"minetest", "ItemStack",
+	"vector",
+
+	"default",
+	"moretrees",
+}