[librsvg: 5/15] derive(Default) for Path

[Federico Mena Quintero <federico src gnome org>]

commit 0910b3ecccdcda13446f5a9585a064e581bae1ea
Author: Federico Mena Quintero <federico gnome org>
Date:   Tue Dec 1 14:31:22 2020 -0600

    derive(Default) for Path
    
    This struct has two boxed slices, and we actually want the default to be
    slices with zero elements - so this matches the Default for Box<[T; 0]>

 src/path_builder.rs | 10 ++++++++++
 1 file changed, 10 insertions(+)
---
diff --git a/src/path_builder.rs b/src/path_builder.rs
index 5d87dad7..5377d8c5 100644
--- a/src/path_builder.rs
+++ b/src/path_builder.rs
@@ -453,6 +453,9 @@ pub struct PathBuilder {
 ///
 /// Each `PathCommand` knows how many coordinates it ought to produce, with
 /// its `num_coordinates` method.
+///
+/// This struct implements `Default`, and it yields an empty path.
+#[derive(Default)]
 pub struct Path {
     commands: Box<[PackedCommand]>,
     coords: Box<[f64]>,
@@ -708,6 +711,13 @@ mod tests {
         assert_eq!(path.iter().count(), 0);
     }
 
+    #[test]
+    fn empty_path() {
+        let path = Path::default();
+        assert!(path.is_empty());
+        assert_eq!(path.iter().count(), 0);
+    }
+
     #[test]
     fn all_commands() {
         let mut builder = PathBuilder::default();