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pub mod stream;

#[cfg(test)]
mod tests {
  use super::*;

  #[test]
  fn compiles() {
    stream::Stream::from(vec![1, 2, 3]);
  }

  #[test]
  fn it_collects_value() {
    let val = vec![1, 2, 3];
    let stream = stream::Stream::from(val);
    let collected = stream.collect();
    let expected: u8 = 0b1;
    assert_eq!(expected, *collected.get(0).unwrap());
  }

  #[test]
  fn it_maps_ints() {
    let val = vec![1, 2, 3];
    let mapped_vals = stream::Stream::from(val).map(|v| v * 2).collect();

    assert_eq!(2, *mapped_vals.get(0).unwrap());
    assert_eq!(4, *mapped_vals.get(1).unwrap());
    assert_eq!(6, *mapped_vals.get(2).unwrap());
  }

  #[test]
  fn it_maps_strings() {
    let val = vec![
      String::from("foo"),
      String::from("bar"),
      String::from("baz"),
    ];
    let mapped_vals = stream::Stream::from(val)
      .map(|v: String| v.to_uppercase())
      .collect();

    assert_eq!("FOO", *mapped_vals.get(0).unwrap());
    assert_eq!("BAR", *mapped_vals.get(1).unwrap());
    assert_eq!("BAZ", *mapped_vals.get(2).unwrap());
  }

  #[test]
  fn it_filters_ints() {
    let val: Vec<i32> = vec![1, 2, 3];
    let filtered_vals = stream::Stream::from(val).filter(|v| v >= &2).collect();

    assert_eq!(2, *filtered_vals.get(0).unwrap());
    assert_eq!(3, *filtered_vals.get(1).unwrap());
  }
}