Refactor: Pull display code out to different file

src/display.rs

@@ -0,0 +1,130 @@
+extern crate ansi_term;
+
+use dust::Node;
+use std::cmp;
+use self::ansi_term::Colour::Fixed;
+
+pub fn display(permissions: bool, to_display: &Vec<&Node>) -> () {
+    if !permissions {
+        eprintln!("Did not have permissions for all directories");
+    }
+
+    display_node(to_display[0], &to_display, true, 1, "")
+}
+
+fn display_node<S: Into<String>>(
+    node_to_print: &Node,
+    to_display: &Vec<&Node>,
+    is_first: bool,
+    depth: u8,
+    indentation_str: S,
+) {
+    let mut is = indentation_str.into();
+    print_this_node(node_to_print, is_first, depth, is.as_ref());
+
+    is = is.replace("└─┬", "  ");
+    is = is.replace("└──", "  ");
+    is = is.replace("├──", "│ ");
+    is = is.replace("├─┬", "│ ");
+
+    let printable_node_slashes = node_to_print.entry().name().matches('/').count();
+
+    let mut num_siblings = to_display.iter().fold(0, |a, b| {
+        if node_to_print.children().contains(b)
+            && b.entry().name().matches('/').count() == printable_node_slashes + 1
+        {
+            a + 1
+        } else {
+            a
+        }
+    });
+
+    let mut is_biggest = true;
+    for node in to_display {
+        if node_to_print.children().contains(node) {
+            let has_display_children = node.children()
+                .iter()
+                .fold(false, |has_kids, n| has_kids || to_display.contains(&n));
+
+            let has_children = node.children().len() > 0 && has_display_children;
+            if node.entry().name().matches('/').count() == printable_node_slashes + 1 {
+                num_siblings -= 1;
+
+                let tree_chars = {
+                    if num_siblings == 0 {
+                        if has_children {
+                            "└─┬"
+                        } else {
+                            "└──"
+                        }
+                    } else {
+                        if has_children {
+                            "├─┬"
+                        } else {
+                            "├──"
+                        }
+                    }
+                };
+                display_node(
+                    &node,
+                    to_display,
+                    is_biggest,
+                    depth + 1,
+                    is.to_string() + tree_chars,
+                );
+                is_biggest = false;
+            }
+        }
+    }
+}
+
+fn print_this_node(node_to_print: &Node, is_biggest: bool, depth: u8, indentation_str: &str) {
+    let padded_size = format!("{:>5}", human_readable_number(node_to_print.entry().size()),);
+    println!(
+        "{} {} {}",
+        if is_biggest {
+            Fixed(196).paint(padded_size)
+        } else {
+            Fixed(7).paint(padded_size)
+        },
+        indentation_str,
+        Fixed(7)
+            .on(Fixed(cmp::min(8, (depth) as u8) + 231))
+            .paint(node_to_print.entry().name().to_string())
+    );
+}
+
+fn human_readable_number(size: u64) -> (String) {
+    let units = vec!["T", "G", "M", "K"]; //make static
+
+    for (i, u) in units.iter().enumerate() {
+        let marker = 1024u64.pow((units.len() - i) as u32);
+        if size >= marker {
+            if size / marker < 10 {
+                return format!("{:.1}{}", (size as f32 / marker as f32), u);
+            } else {
+                return format!("{}{}", (size / marker), u);
+            }
+        }
+    }
+    return format!("{}B", size);
+}
+
+mod tests {
+    #[allow(unused_imports)]
+    use super::*;
+
+    #[test]
+    fn test_human_readable_number() {
+        assert_eq!(human_readable_number(1), "1B");
+        assert_eq!(human_readable_number(956), "956B");
+        assert_eq!(human_readable_number(1004), "1004B");
+        assert_eq!(human_readable_number(1024), "1.0K");
+        assert_eq!(human_readable_number(1536), "1.5K");
+        assert_eq!(human_readable_number(1024 * 512), "512K");
+        assert_eq!(human_readable_number(1024 * 1024), "1.0M");
+        assert_eq!(human_readable_number(1024 * 1024 * 1024 - 1), "1023M");
+        assert_eq!(human_readable_number(1024 * 1024 * 1024 * 20), "20G");
+        assert_eq!(human_readable_number(1024 * 1024 * 1024 * 1024), "1.0T");
+    }
+}