TemplateEnv Globals are removed after a call to Render

[sdegrande]

Here is a small example which fails to run as expected:

#include <iostream>
#include <map>
#include <jinja2cpp/template.h>
#include <jinja2cpp/template_env.h>

int main(int argc, char *argv[])
{
	jinja2::TemplateEnv tplEnv;
	tplEnv.AddGlobal("global_var", jinja2::Value("foo"));
	{
		jinja2::Template tpl(&tplEnv);
		tpl.Load("Hello {{ global_var }}!!!");
		std::string result = tpl.RenderAsString(jinja2::ValuesMap{}).value();
		std::cout << result << std::endl;
	}
	{
		jinja2::Template tpl(&tplEnv);
		tpl.Load("Hello {{ global_var }}!!!");
		std::string result = tpl.RenderAsString(jinja2::ValuesMap{}).value();
		std::cout << result << std::endl;
	}
	return 0;
}

The output is:

Hello foo!!!
Hello !!!

I displayed the content of the Globals before and after the first rendering, using that code:

tplEnv.ApplyGlobals([](jinja2::ValuesMap &map) {
	for (const auto& [key, val] : map) {
		std::cout << "-> tplenv " << key << " " << val.asString() << std::endl;
	}
});

Here is the result:

-> tplenv global_var foo
Hello foo!!!
-> tplenv global_var
Hello !!!

So, something is removing the content of the global vars, which is annoying because currently it means that globals have to be "reloaded" before a call to Render...

Note that MakeCallable globals are still present and working after a call to Render:

#include <iostream>
#include <map>
#include <jinja2cpp/template.h>
#include <jinja2cpp/template_env.h>
#include <jinja2cpp/user_callable.h>

int main(int argc, char *argv[])
{
	jinja2::TemplateEnv tplEnv;
	tplEnv.AddGlobal("global_var", jinja2::Value("foo"));
	tplEnv.AddGlobal("global_fn", jinja2::MakeCallable([]() { return "bar";	}));
	{
		jinja2::Template tpl(&tplEnv);
		tpl.Load("Hello {{ global_var }} {{ global_fn() }}!!!");
		std::string result = tpl.RenderAsString(jinja2::ValuesMap{}).value();
		std::cout << result << std::endl;
	}
	{
		jinja2::Template tpl(&tplEnv);
		tpl.Load("Hello {{ global_var }} {{ global_fn() }}!!!");
		std::string result = tpl.RenderAsString(jinja2::ValuesMap{}).value();
		std::cout << result << std::endl;
	}
	return 0;
}

returns:

Hello foo bar!!!
Hello  bar!!!

[rmorozov]

Sorry, for not reacting earlier, I am doing some investigations.

Hope I'll manage to fix it and bump deps.

[sdegrande]

Thanks. I also hope you'll fix it ! :-)

[rmorozov]

@sdegrande , please check this fix, feel free to reopen issue if it still exists.