Add test for environment variable with empty value

Author: tatzyr

goos/api_test.go

@@ -14,6 +14,9 @@ func TestApi(t *testing.T) {
 	os.Setenv("ENV_VAR", "TEST=1")
 	defer os.Unsetenv("ENV_VAR")
 
+	os.Setenv("EMPTY_VAR", "")
+	defer os.Unsetenv("EMPTY_VAR")
+
 	preload := tests.SeveralPreloadFuncs(
 		runtime.Preload,
 		Preload,

goos/test/test_api.lua

@@ -35,4 +35,6 @@ function Test_environ(t)
     assert(env.PATH or env.Path, "PATH environment variable should exist")
     -- Test environment variable with equals sign in value
     assert(env.ENV_VAR == "TEST=1", "ENV_VAR should be TEST=1")
+    -- Test environment variable with empty value
+    assert(env.EMPTY_VAR == "", "EMPTY_VAR should be empty string")
 end