Simplify tests

dust sort is now more predictable as it orders first by size and second
by name.

Walkdir still gives different iteration orders on different systems so
all output is not entirely predictable

src/utils/mod.rs

@@ -1,5 +1,6 @@
 use std::collections::HashMap;
 use std::collections::HashSet;
+use std::cmp::Ordering;
 
 use walkdir::WalkDir;
 
@@ -80,10 +81,18 @@ fn examine_dir(
         }
     }
 }
+pub fn compare_tuple(a :&(String, u64), b: &(String, u64)) -> Ordering {
+    let result = b.1.cmp(&a.1);
+    if result == Ordering::Equal {
+        a.0.cmp(&b.0)
+    } else {
+        result
+    }
+}
 
 pub fn sort<'a>(data: HashMap<String, u64>) -> Vec<(String, u64)> {
     let mut new_l: Vec<(String, u64)> = data.iter().map(|(a, b)| (a.clone(), *b)).collect();
-    new_l.sort_by(|a, b| b.1.cmp(&a.1));
+    new_l.sort_by(|a, b| compare_tuple(&a, &b));
     new_l
 }