Add --squeeze/-s option

Co-authored-by: einfachIrgendwer0815 <85333734+einfachIrgendwer0815@users.noreply.github.com>

src/bin/bat/app.rs

@@ -290,6 +290,11 @@ impl App {
             #[cfg(feature = "lessopen")]
             use_lessopen: self.matches.get_flag("lessopen"),
             set_terminal_title: self.matches.get_flag("set-terminal-title"),
+            squeeze_lines: if self.matches.get_flag("squeeze") {
+                1
+            } else {
+                0
+            },
         })
     }
 

src/bin/bat/clap_app.rs

@@ -387,6 +387,14 @@ pub fn build_app(interactive_output: bool) -> Command {
                 .help("Display all supported highlighting themes.")
                 .long_help("Display a list of supported themes for syntax highlighting."),
         )
+        .arg(
+            Arg::new("squeeze")
+                .long("squeeze")
+                .short('s')
+                .action(ArgAction::SetTrue)
+                .help("Squeeze consecutive empty lines.")
+                .long_help("Squeeze consecutive empty lines into a single empty line.")
+        )
         .arg(
             Arg::new("style")
                 .long("style")

src/config.rs

@@ -97,6 +97,9 @@ pub struct Config<'a> {
 
     // Weather or not to set terminal title when using a pager
     pub set_terminal_title: bool,
+
+    /// The maximum number of consecutive empty lines to display
+    pub squeeze_lines: usize,
 }
 
 #[cfg(all(feature = "minimal-application", feature = "paging"))]

src/printer.rs

@@ -187,6 +187,7 @@ pub(crate) struct InteractivePrinter<'a> {
     pub line_changes: &'a Option<LineChanges>,
     highlighter_from_set: Option<HighlighterFromSet<'a>>,
     background_color_highlight: Option<Color>,
+    consecutive_empty_lines: usize,
 }
 
 impl<'a> InteractivePrinter<'a> {
@@ -272,6 +273,7 @@ impl<'a> InteractivePrinter<'a> {
             line_changes,
             highlighter_from_set,
             background_color_highlight,
+            consecutive_empty_lines: 0,
         })
     }
 
@@ -577,6 +579,18 @@ impl<'a> Printer for InteractivePrinter<'a> {
             return Ok(());
         }
 
+        // Skip squeezed lines.
+        if self.config.squeeze_lines > 0 {
+            if line.trim_end_matches(|c| c == '\r' || c == '\n').is_empty() {
+                self.consecutive_empty_lines += 1;
+                if self.consecutive_empty_lines > self.config.squeeze_lines {
+                    return Ok(());
+                }
+            } else {
+                self.consecutive_empty_lines = 0;
+            }
+        }
+
         let mut cursor: usize = 0;
         let mut cursor_max: usize = self.config.term_width;
         let mut cursor_total: usize = 0;