nyavascript 0.1.0

use crate::evaluate::Environment as Env;
use super::*;

#[test]
fn env_can_get_bindings_defined_in_scope_higher_than_current() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".to_owned(), SXRef::number(1));

    let mut scope2 = HashMap::new();
    scope2.insert("bar".to_owned(), SXRef::number(2));

    let mut env = Env::new();
    env.push(scope1);
    env.push(scope2);

    let expected = SXRef::number(1);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn env_can_shadow_already_defined_bindings() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".to_owned(), SXRef::number(1));

    let mut scope2 = HashMap::new();
    scope2.insert("foo".to_owned(), SXRef::number(2));

    let mut env = Env::new();
    env.push(scope1);
    env.push(scope2);

    let expected = SXRef::number(2);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn env_can_get_bindings_defined_in_current_scope() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".into(), SXRef::number(1));

    let mut env = Env::new();
    env.push(scope1);

    let expected = SXRef::number(1);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn env_returns_nil_for_undefined_bindings() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".into(), SXRef::number(1));

    let mut env = Env::new();
    env.push(scope1);

    let expected = SXRef::nil();

    let actual = env.get("bar");

    assert_eq!(expected, actual);
}

#[test]
fn env_can_define_global_vars() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".into(), SXRef::number(1));

    let mut env = Env::new();
    env.push(scope1);

    let expected = SXRef::nil();

    let actual = env.get("bar");

    assert_eq!(expected, actual);
}

#[test]
fn local_shadows_lib() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".into(), SXRef::number(1));

    let mut lib1 = HashMap::new();
    lib1.insert("foo".into(), SXRef::number(2));

    let mut env = Env::new();
    env.push_lib(lib1);
    env.push(scope1);

    let expected = SXRef::number(1);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn local_shadows_global() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".into(), SXRef::number(1));

    let mut env = Env::new();
    env.defun("foo".into(), SXRef::number(2));
    env.push(scope1);

    let expected = SXRef::number(1);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn lib_shadows_global() {
    let mut lib1 = HashMap::new();
    lib1.insert("foo".into(), SXRef::number(1));

    let mut env = Env::new();
    env.defun("foo".into(), SXRef::number(2));
    env.push(lib1);

    let expected = SXRef::number(1);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn push_lib_pushes_to_lib_not_local() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".into(), SXRef::number(1));

    let mut lib1 = HashMap::new();
    lib1.insert("foo".into(), SXRef::number(2));

    let mut env = Env::new();
    env.push(scope1);
    env.push_lib(lib1);

    let expected = SXRef::number(1);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn defun_adds_global_not_scope() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".into(), SXRef::number(1));

    let mut env = Env::new();
    env.push(scope1);
    env.defun("foo".into(), SXRef::number(2));

    let expected = SXRef::number(1);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn set_adds_to_last_in_scope() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".into(), SXRef::number(1));

    let scope2 = HashMap::new();

    let mut env = Env::new();
    env.push(scope1);
    env.push(scope2);
    env.set("foo".into(), SXRef::number(2));

    let expected = SXRef::number(2);

    let actual = env.get("foo");

    assert_eq!(expected, actual);

    env.pop();

    let expected = SXRef::number(1);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn delete_removes_from_last_in_scope() {
    let mut scope1 = HashMap::new();
    scope1.insert("foo".into(), SXRef::number(1));

    let mut scope2 = HashMap::new();
    scope2.insert("foo".into(), SXRef::number(2));

    let mut env = Env::new();
    env.push(scope1);
    env.push(scope2);

    let expected = SXRef::number(2);

    let actual = env.get("foo");

    assert_eq!(expected, actual);

    env.delete("foo");

    let expected = SXRef::number(1);

    let actual = env.get("foo");

    assert_eq!(expected, actual);
}

#[test]
fn env_initializes_with_a_scope() {
    let mut env = Env::new();

    env.pop();
}