Initial commit

src/flatten.rs

@@ -0,0 +1,124 @@
+#![allow(clippy::implicit_hasher)]
+
+use crate::identifier::{TreeIdentifier, TreeIdentifierVec};
+use crate::TreeItem;
+use std::collections::HashSet;
+
+pub struct Flattened<'a> {
+    pub identifier: Vec<usize>,
+    pub item: &'a TreeItem<'a>,
+}
+
+impl<'a> Flattened<'a> {
+    pub fn depth(&self) -> usize {
+        self.identifier.len() - 1
+    }
+}
+
+pub fn flatten<'a>(
+    opened: &HashSet<TreeIdentifierVec>,
+    items: &'a [TreeItem<'a>],
+) -> Vec<Flattened<'a>> {
+    internal(opened, items, &[])
+}
+
+fn internal<'a>(
+    opened: &HashSet<TreeIdentifierVec>,
+    items: &'a [TreeItem<'a>],
+    current: TreeIdentifier,
+) -> Vec<Flattened<'a>> {
+    let mut result = Vec::new();
+
+    for (index, item) in items.iter().enumerate() {
+        let mut child_identifier = current.to_vec();
+        child_identifier.push(index);
+
+        result.push(Flattened {
+            item,
+            identifier: child_identifier.to_vec(),
+        });
+
+        if opened.contains(&child_identifier) {
+            let mut child_result = internal(opened, &item.children, &child_identifier);
+            result.append(&mut child_result);
+        }
+    }
+
+    result
+}
+
+#[cfg(test)]
+fn get_naive_string_from_text<'a>(text: &tui::text::Text<'a>) -> String {
+    text.lines
+        .first()
+        .unwrap()
+        .0
+        .first()
+        .unwrap()
+        .content
+        .to_string()
+}
+
+#[cfg(test)]
+fn get_example_tree_items<'a>() -> Vec<TreeItem<'a>> {
+    vec![
+        TreeItem::new_leaf("a"),
+        TreeItem::new(
+            "b",
+            vec![
+                TreeItem::new_leaf("c"),
+                TreeItem::new("d", vec![TreeItem::new_leaf("e"), TreeItem::new_leaf("f")]),
+                TreeItem::new_leaf("g"),
+            ],
+        ),
+        TreeItem::new_leaf("h"),
+    ]
+}
+
+#[test]
+fn get_opened_nothing_opened_is_top_level() {
+    let items = get_example_tree_items();
+    let opened = HashSet::new();
+    let result = flatten(&opened, &items);
+    let result_text: Vec<_> = result
+        .iter()
+        .map(|o| get_naive_string_from_text(&o.item.text))
+        .collect();
+    assert_eq!(result_text, ["a", "b", "h"]);
+}
+
+#[test]
+fn get_opened_wrong_opened_is_only_top_level() {
+    let items = get_example_tree_items();
+    let opened = [vec![0], vec![1, 1]].iter().cloned().collect();
+    let result = flatten(&opened, &items);
+    let result_text: Vec<_> = result
+        .iter()
+        .map(|o| get_naive_string_from_text(&o.item.text))
+        .collect();
+    assert_eq!(result_text, ["a", "b", "h"]);
+}
+
+#[test]
+fn get_opened_one_is_opened() {
+    let items = get_example_tree_items();
+    let opened = [vec![1]].iter().cloned().collect();
+    let result = flatten(&opened, &items);
+    let result_text: Vec<_> = result
+        .iter()
+        .map(|o| get_naive_string_from_text(&o.item.text))
+        .collect();
+    assert_eq!(result_text, ["a", "b", "c", "d", "g", "h"]);
+}
+
+#[test]
+fn get_opened_all_opened() {
+    let items = get_example_tree_items();
+    let opened = [vec![1], vec![1, 1]].iter().cloned().collect();
+    let result = flatten(&opened, &items);
+    let result_text: Vec<_> = result
+        .iter()
+        .map(|o| get_naive_string_from_text(&o.item.text))
+        .collect();
+    assert_eq!(result_text, ["a", "b", "c", "d", "e", "f", "g", "h"]);
+}