low-level: stdio: fix: make progress text properly optional

.. such that receivers can differentiate between these two cases more
clearly.

Sometimes, the `progress` sub does not get passed a text (on purpose!),
just updating the progress ratio. This would cause log messages to be
written out which could indicate missing text and look rather weird.

Signed-off-by: Christoph Heiss <c.heiss@proxmox.com>

Proxmox/UI/StdIO.pm

@@ -70,9 +70,11 @@ sub display_html {
 sub progress {
     my ($self, $ratio, $text) = @_;
 
-    $text = '' if !defined($text);
+    if (defined($text)) {
-
 	send_msg('progress', ratio => $ratio, text => $text);
+    } else {
+	send_msg('progress', ratio => $ratio);
+    }
 }
 
 sub process_events {

proxmox-auto-installer/src/bin/proxmox-auto-installer.rs

@@ -205,7 +205,11 @@ fn run_installation(
                 }
                 LowLevelMessage::Progress { ratio, text } => {
                     let percentage = ratio * 100.;
+                    if let Some(text) = text {
                         info!("progress {percentage:>5.1} % - {text}");
+                    } else {
+                        info!("progress {percentage:>5.1} %");
+                    }
                 }
                 LowLevelMessage::Finished { state, message } => {
                     if state == "err" {

proxmox-installer-common/src/setup.rs

@@ -571,6 +571,6 @@ pub enum LowLevelMessage {
     },
     Progress {
         ratio: f32,
-        text: String,
+        text: Option<String>,
     },
 }

proxmox-tui-installer/src/views/install_progress.rs

@@ -127,11 +127,18 @@ impl InstallProgressView {
                     }),
                     LowLevelMessage::Progress { ratio, text } => {
                         counter.set((ratio * 100.).floor() as usize);
+                        if let Some(text) = text {
                             cb_sink.send(Box::new(move |siv| {
-                            siv.call_on_name(Self::PROGRESS_TEXT_VIEW_ID, |v: &mut TextView| {
+                                siv.call_on_name(
+                                    Self::PROGRESS_TEXT_VIEW_ID,
+                                    |v: &mut TextView| {
                                         v.set_content(text);
-                            });
+                                    },
+                                );
                             }))
+                        } else {
+                            Ok(())
+                        }
                     }
                     LowLevelMessage::Finished { state, message } => {
                         counter.set(100);
@@ -310,7 +317,7 @@ mod tests {
                 next_msg(&mut reader),
                 Some(LowLevelMessage::Progress {
                     ratio: (i as f32) / 1000.,
-                    text: format!("foo {i}"),
+                    text: Some(format!("foo {i}")),
                 }),
             );
         }

test/ui2-stdio.pl

@@ -81,7 +81,7 @@ if ($child_pid) {
 	'should get 20% done progress message');
 
     is_deeply(
-	$next_msg->(), { type => 'progress', ratio => 0.2, text => '' },
+	$next_msg->(), { type => 'progress', ratio => 0.2, },
 	'should get progress continuation message');
 
     is_deeply(