Fix percent initial value when there is no length

src/in_memory.rs

@@ -67,7 +67,7 @@ impl TermLike for InMemoryTerm {
                 .state
                 .lock()
                 .unwrap()
-                .write_str(&*format!("\x1b[{}A", n)),
+                .write_str(&format!("\x1b[{}A", n)),
         }
     }
 
@@ -78,7 +78,7 @@ impl TermLike for InMemoryTerm {
                 .state
                 .lock()
                 .unwrap()
-                .write_str(&*format!("\x1b[{}B", n)),
+                .write_str(&format!("\x1b[{}B", n)),
         }
     }
 
@@ -89,7 +89,7 @@ impl TermLike for InMemoryTerm {
                 .state
                 .lock()
                 .unwrap()
-                .write_str(&*format!("\x1b[{}C", n)),
+                .write_str(&format!("\x1b[{}C", n)),
         }
     }
 
@@ -100,7 +100,7 @@ impl TermLike for InMemoryTerm {
                 .state
                 .lock()
                 .unwrap()
-                .write_str(&*format!("\x1b[{}D", n)),
+                .write_str(&format!("\x1b[{}D", n)),
         }
     }
 

src/state.rs

@@ -245,7 +245,7 @@ impl ProgressState {
     pub fn fraction(&self) -> f32 {
         let pos = self.pos.pos.load(Ordering::Relaxed);
         let pct = match (pos, self.len) {
-            (_, None) => 1.0,
+            (_, None) => 0.0,
             (_, Some(0)) => 1.0,
             (0, _) => 0.0,
             (pos, Some(len)) => pos as f32 / len as f32,

src/style.rs

@@ -190,11 +190,7 @@ impl ProgressStyle {
         let entirely_filled = fill as usize;
         // 1 if the bar is not entirely empty or full (meaning we need to draw the "current"
         // character between the filled and "to do" segment), 0 otherwise.
-        let head = if fill > 0.0 && entirely_filled < width {
-            1
-        } else {
-            0
-        };
+        let head = usize::from(fill > 0.0 && entirely_filled < width);
 
         let cur = if head == 1 {
             // Number of fine-grained progress entries in progress_chars.
@@ -423,7 +419,7 @@ impl<'a> WideElement<'a> {
         buf: &mut String,
         width: u16,
     ) -> String {
-        let left = (width as usize).saturating_sub(measure_text_width(&*cur.replace('\x00', "")));
+        let left = (width as usize).saturating_sub(measure_text_width(&cur.replace('\x00', "")));
         match self {
             Self::Bar { alt_style } => cur.replace(
                 '\x00',

tests/render.rs

@@ -60,6 +60,39 @@ fn progress_bar_builder_method_order() {
     );
 }
 
+#[test]
+fn progress_bar_percent_with_no_length() {
+    let in_mem = InMemoryTerm::new(10, 80);
+    let pb = ProgressBar::with_draw_target(
+        None,
+        ProgressDrawTarget::term_like(Box::new(in_mem.clone())),
+    )
+    .with_style(ProgressStyle::with_template("{wide_bar} {percent}%").unwrap());
+
+    assert_eq!(in_mem.contents(), String::new());
+
+    pb.tick();
+
+    assert_eq!(
+        in_mem.contents(),
+        "░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░ 0%"
+    );
+
+    pb.set_length(10);
+
+    pb.inc(1);
+    assert_eq!(
+        in_mem.contents(),
+        "███████░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░ 10%"
+    );
+
+    pb.finish();
+    assert_eq!(
+        in_mem.contents(),
+        "███████████████████████████████████████████████████████████████████████████ 100%"
+    );
+}
+
 #[test]
 fn multi_progress_single_bar_and_leave() {
     let in_mem = InMemoryTerm::new(10, 80);