style: Latest clippy suggestions (#2048)

Have fixed a few new suggestions from the latest version of clippy.

src/formatter/string_formatter.rs

@@ -621,8 +621,10 @@ mod tests {
     #[test]
     fn test_variable_holder() {
         const FORMAT_STR: &str = "($a [($b) $c](none $s)) $d [t]($t)";
-        let expected_variables =
-            BTreeSet::from_iter(vec!["a", "b", "c", "d"].into_iter().map(String::from));
+        let expected_variables = vec!["a", "b", "c", "d"]
+            .into_iter()
+            .map(String::from)
+            .collect();
 
         let formatter = StringFormatter::new(FORMAT_STR).unwrap().map(empty_mapper);
         let variables = formatter.get_variables();
@@ -632,7 +634,7 @@ mod tests {
     #[test]
     fn test_style_variable_holder() {
         const FORMAT_STR: &str = "($a [($b) $c](none $s)) $d [t]($t)";
-        let expected_variables = BTreeSet::from_iter(vec!["s", "t"].into_iter().map(String::from));
+        let expected_variables = vec!["s", "t"].into_iter().map(String::from).collect();
 
         let formatter = StringFormatter::new(FORMAT_STR).unwrap().map(empty_mapper);
         let variables = formatter.get_style_variables();

src/modules/cmd_duration.rs

@@ -132,23 +132,23 @@ mod tests {
 
     #[test]
     fn test_500ms() {
-        assert_eq!(render_time(500 as u128, true), "500ms")
+        assert_eq!(render_time(500_u128, true), "500ms")
     }
     #[test]
     fn test_10s() {
-        assert_eq!(render_time(10_000 as u128, true), "10s")
+        assert_eq!(render_time(10_000_u128, true), "10s")
     }
     #[test]
     fn test_90s() {
-        assert_eq!(render_time(90_000 as u128, true), "1m30s")
+        assert_eq!(render_time(90_000_u128, true), "1m30s")
     }
     #[test]
     fn test_10110s() {
-        assert_eq!(render_time(10_110_000 as u128, true), "2h48m30s")
+        assert_eq!(render_time(10_110_000_u128, true), "2h48m30s")
     }
     #[test]
     fn test_1d() {
-        assert_eq!(render_time(86_400_000 as u128, true), "1d")
+        assert_eq!(render_time(86_400_000_u128, true), "1d")
     }
 
     #[test]

src/test/mod.rs

@@ -89,7 +89,7 @@ impl<'a> ModuleRenderer<'a> {
         // convention was that there would be no module but None. This is nowadays not anymore
         // the case (to get durations for all modules). So here we make it so, that an empty
         // module returns None in the tests...
-        ret.filter(|s| s != "")
+        ret.filter(|s| !s.is_empty())
     }
 }