remove unnecessary result handling in page_up

Author: aaron-ang

src/uu/more/src/more.rs

@@ -415,7 +415,7 @@ fn process_events(pager: &mut Pager, stdout: &mut Stdout, options: &Options) ->
                 modifiers: KeyModifiers::NONE,
                 ..
             }) => {
-                pager.page_up()?;
+                pager.page_up();
             }
             Event::Key(KeyEvent {
                 code: KeyCode::Char('k'),
@@ -605,7 +605,7 @@ impl<'a> Pager<'a> {
         self.upper_mark = self.upper_mark.saturating_add(1);
     }
 
-    fn page_up(&mut self) -> UResult<()> {
+    fn page_up(&mut self) {
         self.eof_reached = false;
         // Move the viewing window up by the number of lines to display
         self.upper_mark = self
@@ -622,7 +622,6 @@ impl<'a> Pager<'a> {
                 self.upper_mark = self.upper_mark.saturating_sub(1);
             }
         }
-        Ok(())
     }
 
     fn prev_line(&mut self) {
@@ -645,7 +644,7 @@ impl<'a> Pager<'a> {
         Ok(())
     }
 
-    fn draw_lines(&mut self, stdout: &mut Stdout) -> UResult<()> {
+    fn draw_lines(&mut self, stdout: &mut impl Write) -> UResult<()> {
         // Clear current prompt line
         stdout.queue(Clear(ClearType::CurrentLine))?;
 
@@ -862,7 +861,7 @@ mod tests {
         assert_eq!(pager.upper_mark, pager.content_rows);
         pager.next_line();
         assert_eq!(pager.upper_mark, pager.content_rows + 1);
-        pager.page_up().unwrap();
+        pager.page_up();
         assert_eq!(pager.upper_mark, 1);
         pager.prev_line();
         assert_eq!(pager.upper_mark, 0);
@@ -888,4 +887,17 @@ mod tests {
         let pager = TestPagerBuilder::new(&content).from_line(3).build();
         assert_eq!(pager.upper_mark, 3);
     }
+
+    #[test]
+    fn test_silent_mode() {
+        let content = (1..=5).map(|i| i.to_string() + "\n").collect::<String>();
+        let mut pager = TestPagerBuilder::new(&content)
+            .from_line(3)
+            .silent(true)
+            .build();
+        let mut buf = Vec::new();
+        pager.draw_prompt(&mut buf, None);
+        let buf_str = String::from_utf8_lossy(&buf);
+        assert!(buf_str.contains(HELP_MESSAGE));
+    }
 }