test(Scrollbar): port test 🚨

src/widgets/scrollbar.rs

@@ -631,7 +631,10 @@ impl<'a> StatefulWidget for Scrollbar<'a> {
 
 #[cfg(test)]
 mod tests {
+    use itertools::Itertools;
+    use rstest::rstest;
     use strum::ParseError;
+    use unicode_width::UnicodeWidthStr;
 
     use super::*;
     use crate::{
@@ -705,29 +708,34 @@ mod tests {
         );
     }
 
-    #[test]
-    fn test_renders_empty_with_content_length_is_zero() {
-        let mut buffer = Buffer::empty(Rect::new(0, 0, 2, 8));
-        let mut state = ScrollbarState::default().position(0);
+    #[rstest]
+    #[case("        ", 0)]
+    #[case("████████", 1)]
+    #[case("████████", 2)]
+    #[case("████████", 3)]
+    #[case("████████", 4)]
+    #[case("████████", 5)]
+    #[case("████████", 6)]
+    #[case("████████", 7)]
+    #[case("████████", 8)]
+    fn test_renders_empty_with_content_length_is_zero(
+        #[case] expected: &str,
+        #[case] content_length: usize,
+    ) {
+        let size = expected.width();
+        let mut buffer = Buffer::empty(Rect::new(0, 0, 2, size as u16));
+        let mut state = ScrollbarState::new(content_length).position(0);
         Scrollbar::default()
             .begin_symbol(None)
             .end_symbol(None)
             .render(buffer.area, &mut buffer, &mut state);
-        assert_buffer_eq!(
-            buffer,
-            Buffer::with_lines(vec!["  ", "  ", "  ", "  ", "  ", "  ", "  ", "  "])
-        );
-
-        let mut buffer = Buffer::empty(Rect::new(0, 0, 2, 8));
-        let mut state = ScrollbarState::new(8).position(0);
-        Scrollbar::default()
-            .begin_symbol(None)
-            .end_symbol(None)
-            .render(buffer.area, &mut buffer, &mut state);
-        assert_buffer_eq!(
-            buffer,
-            Buffer::with_lines(vec![" █", " █", " █", " █", " █", " █", " █", " █"])
-        );
+        let empty_string: String = " ".repeat(size);
+        let bar = empty_string
+            .chars()
+            .zip(expected.chars())
+            .map(|(a, b)| format!("{a}{b}"))
+            .collect_vec();
+        assert_buffer_eq!(buffer, Buffer::with_lines(bar));
     }
 
     #[test]
@@ -1128,4 +1136,341 @@ mod tests {
             assert_buffer_eq!(buffer, Buffer::with_lines(expected.clone()));
         }
     }
+
+    #[rstest]
+    #[case("██", 0, 2, "position_0")]
+    #[case("██", 1, 2, "position_1")]
+    fn render_scrollbar_simplest(
+        #[case] expected: &str,
+        #[case] position: usize,
+        #[case] content_length: usize,
+        #[case] assertion_message: &str,
+    ) {
+        let size = expected.width() as u16;
+        let mut buffer = Buffer::empty(Rect::new(0, 0, size, 1));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::HorizontalBottom)
+            .begin_symbol(None)
+            .end_symbol(None)
+            .render(buffer.area, &mut buffer, &mut state);
+        assert_eq!(
+            buffer,
+            Buffer::with_lines(vec![expected]),
+            "{}",
+            assertion_message
+        );
+    }
+
+    #[rstest]
+    #[case("##########", 0, 10, "position_0")]
+    #[case("##########", 1, 10, "position_1")]
+    #[case("##########", 2, 10, "position_2")]
+    #[case("##########", 3, 10, "position_3")]
+    #[case("##########", 4, 10, "position_4")]
+    #[case("##########", 5, 10, "position_5")]
+    #[case("##########", 6, 10, "position_6")]
+    #[case("##########", 7, 10, "position_7")]
+    #[case("##########", 8, 10, "position_8")]
+    #[case("##########", 9, 10, "position_9")]
+    fn render_scrollbar_simple(
+        #[case] expected: &str,
+        #[case] position: usize,
+        #[case] content_length: usize,
+        #[case] assertion_message: &str,
+    ) {
+        let size = expected.width();
+        let mut buffer = Buffer::empty(Rect::new(0, 0, size as u16, 1));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::HorizontalTop)
+            .begin_symbol(None)
+            .end_symbol(None)
+            .track_symbol(Some("-"))
+            .thumb_symbol("#")
+            .render(buffer.area, &mut buffer, &mut state);
+        assert_eq!(
+            buffer,
+            Buffer::with_lines(vec![expected]),
+            "{}",
+            assertion_message,
+        );
+    }
+
+    #[rstest]
+    #[case("          ", 0, 0, "position_0")]
+    fn render_scrollbar_nobar(
+        #[case] expected: &str,
+        #[case] position: usize,
+        #[case] content_length: usize,
+        #[case] assertion_message: &str,
+    ) {
+        let size = expected.width();
+        let mut buffer = Buffer::empty(Rect::new(0, 0, size as u16, 1));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::HorizontalTop)
+            .begin_symbol(None)
+            .end_symbol(None)
+            .track_symbol(Some("-"))
+            .thumb_symbol("#")
+            .render(buffer.area, &mut buffer, &mut state);
+        assert_eq!(
+            buffer,
+            Buffer::with_lines(vec![expected]),
+            "{}",
+            assertion_message,
+        );
+    }
+
+    #[rstest]
+    #[case("##########", 0, 1, "position_0")]
+    fn render_scrollbar_fullbar(
+        #[case] expected: &str,
+        #[case] position: usize,
+        #[case] content_length: usize,
+        #[case] assertion_message: &str,
+    ) {
+        let size = expected.width();
+        let mut buffer = Buffer::empty(Rect::new(0, 0, size as u16, 1));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::HorizontalTop)
+            .begin_symbol(None)
+            .end_symbol(None)
+            .track_symbol(Some("-"))
+            .thumb_symbol("#")
+            .render(buffer.area, &mut buffer, &mut state);
+        assert_eq!(
+            buffer,
+            Buffer::with_lines(vec![expected]),
+            "{}",
+            assertion_message,
+        );
+    }
+
+    #[rstest]
+    #[case("##########", 0, 2, "position_0")]
+    #[case("##########", 1, 2, "position_1")]
+    fn render_scrollbar_almost_fullbar(
+        #[case] expected: &str,
+        #[case] position: usize,
+        #[case] content_length: usize,
+        #[case] assertion_message: &str,
+    ) {
+        let size = expected.width();
+        let mut buffer = Buffer::empty(Rect::new(0, 0, size as u16, 1));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::HorizontalTop)
+            .begin_symbol(None)
+            .end_symbol(None)
+            .track_symbol(Some("-"))
+            .thumb_symbol("#")
+            .render(buffer.area, &mut buffer, &mut state);
+        assert_eq!(
+            buffer,
+            Buffer::with_lines(vec![expected]),
+            "{}",
+            assertion_message,
+        );
+    }
+
+    #[rstest]
+    #[case("██████████", 0, 10, "position_0")]
+    #[case("██████████", 1, 10, "position_1")]
+    #[case("██████████", 2, 10, "position_2")]
+    #[case("██████████", 3, 10, "position_3")]
+    #[case("██████████", 4, 10, "position_4")]
+    #[case("██████████", 5, 10, "position_5")]
+    #[case("██████████", 6, 10, "position_6")]
+    #[case("██████████", 7, 10, "position_7")]
+    #[case("██████████", 8, 10, "position_8")]
+    #[case("██████████", 9, 10, "position_9")]
+    #[case("██████████", 100, 10, "position_out_of_bounds")]
+    fn render_scrollbar_without_symbols(
+        #[case] expected: &str,
+        #[case] position: usize,
+        #[case] content_length: usize,
+        #[case] assertion_message: &str,
+    ) {
+        let size = expected.width() as u16;
+        let mut buffer = Buffer::empty(Rect::new(0, 0, size, 1));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::HorizontalBottom)
+            .begin_symbol(None)
+            .end_symbol(None)
+            .render(buffer.area, &mut buffer, &mut state);
+        assert_eq!(
+            buffer,
+            Buffer::with_lines(vec![expected]),
+            "{}",
+            assertion_message
+        );
+    }
+
+    #[rstest]
+    #[case("<######-->", 0, 10, "position_0")]
+    #[case("<######-->", 1, 10, "position_1")]
+    #[case("<######-->", 2, 10, "position_2")]
+    #[case("<-######->", 3, 10, "position_3")]
+    #[case("<-######->", 4, 10, "position_4")]
+    #[case("<-######->", 5, 10, "position_5")]
+    #[case("<-######->", 6, 10, "position_6")]
+    #[case("<-######->", 7, 10, "position_7")]
+    #[case("<--######>", 8, 10, "position_8")]
+    #[case("<--######>", 9, 10, "position_9")]
+    #[case("<--######>", 10, 10, "position_one_out_of_bounds")]
+    #[case("<--######>", 15, 10, "position_few_out_of_bounds")]
+    #[case("<--######>", 500, 10, "position_very_many_out_of_bounds")]
+    fn render_scrollbar_with_symbols(
+        #[case] expected: &str,
+        #[case] position: usize,
+        #[case] content_length: usize,
+        #[case] assertion_message: &str,
+    ) {
+        let size = expected.width() as u16;
+        let mut buffer = Buffer::empty(Rect::new(0, 0, size, 1));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::HorizontalTop)
+            .begin_symbol(Some("<"))
+            .end_symbol(Some(">"))
+            .track_symbol(Some("-"))
+            .thumb_symbol("#")
+            .render(buffer.area, &mut buffer, &mut state);
+        assert_eq!(
+            buffer,
+            Buffer::with_lines(vec![expected]),
+            "{}",
+            assertion_message,
+        );
+    }
+
+    #[rstest]
+    #[case("██████████", 0, 10, "position_0")]
+    #[case("██████████", 1, 10, "position_1")]
+    #[case("██████████", 2, 10, "position_2")]
+    #[case("██████████", 3, 10, "position_3")]
+    #[case("██████████", 4, 10, "position_4")]
+    #[case("██████████", 5, 10, "position_5")]
+    #[case("██████████", 6, 10, "position_6")]
+    #[case("██████████", 7, 10, "position_7")]
+    #[case("██████████", 8, 10, "position_8")]
+    #[case("██████████", 9, 10, "position_9")]
+    #[case("██████████", 100, 10, "position_out_of_bounds")]
+    fn render_scrollbar_twoline_horizontal(
+        #[case] expected: &str,
+        #[case] position: usize,
+        #[case] content_length: usize,
+        #[case] assertion_message: &str,
+    ) {
+        let size = expected.width() as u16;
+        let mut buffer = Buffer::empty(Rect::new(0, 0, size, 2));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::HorizontalBottom)
+            .begin_symbol(None)
+            .end_symbol(None)
+            .render(buffer.area, &mut buffer, &mut state);
+        let empty_string: String = " ".repeat(size as usize);
+        assert_eq!(
+            buffer,
+            Buffer::with_lines(vec![&empty_string, expected]),
+            "{}",
+            assertion_message
+        );
+
+        let mut buffer = Buffer::empty(Rect::new(0, 0, size, 2));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::HorizontalTop)
+            .begin_symbol(None)
+            .end_symbol(None)
+            .render(buffer.area, &mut buffer, &mut state);
+        let empty_string: String = " ".repeat(size as usize);
+        assert_eq!(
+            buffer,
+            Buffer::with_lines(vec![expected, &empty_string]),
+            "{}",
+            assertion_message
+        );
+    }
+
+    #[rstest]
+    #[case("<######-->", 0, 10, "position_0")]
+    #[case("<######-->", 1, 10, "position_1")]
+    #[case("<######-->", 2, 10, "position_2")]
+    #[case("<-######->", 3, 10, "position_3")]
+    #[case("<-######->", 4, 10, "position_4")]
+    #[case("<-######->", 5, 10, "position_5")]
+    #[case("<-######->", 6, 10, "position_6")]
+    #[case("<-######->", 7, 10, "position_7")]
+    #[case("<--######>", 8, 10, "position_8")]
+    #[case("<--######>", 9, 10, "position_9")]
+    #[case("<--######>", 10, 10, "position_one_out_of_bounds")]
+    fn render_scrollbar_twoline_vertical(
+        #[case] expected: &str,
+        #[case] position: usize,
+        #[case] content_length: usize,
+        #[case] assertion_message: &str,
+    ) {
+        let size = expected.width() as u16;
+        let mut buffer = Buffer::empty(Rect::new(0, 0, 2, size));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::VerticalRight)
+            .begin_symbol(Some("<"))
+            .end_symbol(Some(">"))
+            .track_symbol(Some("-"))
+            .thumb_symbol("#")
+            .render(buffer.area, &mut buffer, &mut state);
+        let empty_string: String = " ".repeat(size as usize);
+        let bar = empty_string
+            .chars()
+            .zip(expected.chars())
+            .map(|(a, b)| format!("{a}{b}"))
+            .collect_vec();
+        assert_eq!(buffer, Buffer::with_lines(bar), "{}", assertion_message);
+
+        let mut buffer = Buffer::empty(Rect::new(0, 0, 2, size));
+        let mut state = ScrollbarState::default()
+            .position(position)
+            .content_length(content_length);
+        Scrollbar::default()
+            .orientation(ScrollbarOrientation::VerticalLeft)
+            .begin_symbol(Some("<"))
+            .end_symbol(Some(">"))
+            .track_symbol(Some("-"))
+            .thumb_symbol("#")
+            .render(buffer.area, &mut buffer, &mut state);
+        let empty_string: String = " ".repeat(size as usize);
+        let bar = expected
+            .chars()
+            .zip(empty_string.chars())
+            .map(|(a, b)| format!("{a}{b}"))
+            .collect_vec();
+        assert_eq!(buffer, Buffer::with_lines(bar), "{}", assertion_message);
+    }
 }