cmd: fix crash if LuaRocks is given a bad LUA_DIR

Includes a regression test.

2 files changed, 36 insertions, 0 deletions

diff --git a/spec/cmd_spec.lua b/spec/cmd_spec.lua
new file mode 100644
index 00000000..70b9625d
--- /dev/null
+++ b/spec/cmd_spec.lua
@@ -0,0 +1,34 @@
+local test_env = require("spec.util.test_env")
+local run = test_env.run
+
+test_env.unload_luarocks()
+
+describe("LuaRocks command line #integration", function()
+   
+   setup(function()
+      test_env.setup_specs()
+   end)
+
+   describe("--version", function()
+      it("returns the LuaRocks version", function()
+         local output = run.luarocks("--version")
+         assert.match("LuaRocks main command-line interface", output, 1, true)
+      end)
+
+      it("runs if Lua detection fails", function()
+         test_env.run_in_tmp(function(tmpdir)
+            test_env.write_file("bad_config.lua", [[
+               variables = {
+                  LUA_DIR = "/bad/lua/dir",
+               }
+            ]], finally)
+            local env = {
+               LUAROCKS_CONFIG = "bad_config.lua"
+            }
+            local output = run.luarocks("--version", env)
+            assert.match("LuaRocks main command-line interface", output, 1, true)
+         end, finally)
+      end)
+   end)
+
+end)
diff --git a/src/luarocks/cmd.lua b/src/luarocks/cmd.lua
index cb669226..bbbdcba1 100644
--- a/src/luarocks/cmd.lua
+++ b/src/luarocks/cmd.lua
@@ -372,6 +372,8 @@ function cmd.run_command(description, commands, external_namespace, ...)
 
    fs.init()
 
+   lua_version = cfg.lua_version
+
    if not lua_found then
       if cfg.variables.LUA_DIR then
          local found = util.find_lua(cfg.variables.LUA_DIR, cfg.lua_version)