AMythicDev · AMythicDev · Mar 15, 2024 · Mar 16, 2024 · Apr 4, 2024 · Apr 13, 2024
diff --git a/Cargo.toml b/Cargo.toml
@@ -27,6 +27,9 @@ regex = { version = "^1", optional = true }
 crossbeam-channel = "^0.5"
 parking_lot = "0.12.1"
 once_cell = { version = "^1.18", features = ["parking_lot"] }
+bytecount = { version = "0.6.7", features = ["runtime-dispatch-simd"] }
+smol_str = "0.2.1"
+arrayvec = "0.7.4"
 
 [features]
 search = [ "regex" ]
@@ -70,3 +73,8 @@ required-features = ["static_output"]
 name = "msg-tokio"
 path = "examples/msg-tokio.rs"
 required-features = ["dynamic_output"]
+
+
+[profile.profiling]
+inherits = "release"
+debug = 1
diff --git a/src/core/init.rs b/src/core/init.rs
@@ -24,6 +24,7 @@ use crate::{
 
 use crossbeam_channel::{Receiver, Sender, TrySendError};
 use crossterm::event;
+use smol_str::ToSmolStr;
 use std::{
     io::{stdout, Stdout},
     panic,
@@ -98,7 +99,7 @@ pub fn init_core(pager: &Pager, rm: RunMode) -> std::result::Result<(), MinusErr
     if *RUNMODE.lock() == RunMode::Static {
         // If stdout is not a tty, write everything and quit
         if !out.is_tty() {
-            write_raw_lines(&mut out, &[ps.screen.orig_text], None)?;
+            write_raw_lines(&mut out, &[ps.screen.orig_text.to_smolstr()], None)?;
             let mut rm = RUNMODE.lock();
             *rm = RunMode::Uninitialized;
             drop(rm);

diff --git a/src/core/utils/display/mod.rs b/src/core/utils/display/mod.rs
@@ -231,7 +231,7 @@ pub fn draw_append_text(
 #[allow(clippy::too_many_arguments)]
 pub fn write_text_checked(
     out: &mut impl Write,
-    lines: &[String],
+    lines: &[Row],
     mut upper_mark: usize,
     rows: usize,
     cols: usize,
@@ -257,7 +257,7 @@ pub fn write_text_checked(
     }
 
     // Add \r to ensure cursor is placed at the beginning of each row
-    let display_lines: &[String] = &lines[upper_mark..lower_mark];
+    let display_lines = &lines[upper_mark..lower_mark];
 
     term::move_cursor(out, 0, 0, false)?;
     term::clear_entire_screen(out, false)?;
@@ -287,7 +287,7 @@ pub fn write_from_pagerstate(out: &mut impl Write, ps: &mut PagerState) -> Resul
     }
 
     // Add \r to ensure cursor is placed at the beginning of each row
-    let display_lines: &[String] = ps
+    let display_lines = ps
         .screen
         .get_formatted_lines_with_bounds(ps.upper_mark, lower_mark);
 
@@ -304,7 +304,7 @@ pub fn write_from_pagerstate(out: &mut impl Write, ps: &mut PagerState) -> Resul
 
 pub fn write_lines(
     out: &mut impl Write,
-    lines: &[String],
+    lines: &[Row],
     cols: usize,
     line_wrapping: bool,
     left_mark: usize,
@@ -320,7 +320,7 @@ pub fn write_lines(
 
 pub fn write_lines_in_horizontal_scroll(
     out: &mut impl Write,
-    lines: &[String],
+        lines: &[Row],
     cols: usize,
     start: usize,
     line_numbers: bool,
@@ -368,7 +368,7 @@ pub fn write_lines_in_horizontal_scroll(
 /// The `\r` resets the cursor to the start of the line.
 pub fn write_raw_lines(
     out: &mut impl Write,
-    lines: &[String],
+    lines: &[Row],
     initial: Option<&str>,
 ) -> Result<(), MinusError> {
     for line in lines {

diff --git a/src/lib.rs b/src/lib.rs
@@ -12,6 +12,7 @@
 #![warn(clippy::nursery)]
 #![allow(clippy::doc_markdown)]
 #![cfg_attr(doctest, doc = include_str!("../README.md"))]
+#![feature(test)]
 
 //! `minus`: A library for asynchronous terminal [paging], written in Rust.
 //!

diff --git a/src/screen/data_source.rs b/src/screen/data_source.rs
@@ -0,0 +1,39 @@
+use arrayvec::ArrayString;
+
+type InsertionBuffer = ArrayString<240>;
+
+pub trait DataSource {
+    fn reads_forward(&mut self, buffer: &mut InsertionBuffer) -> bool;
+    fn reads_backward(&mut self, buffer: &mut InsertionBuffer) -> bool;
+    fn readr_line(&mut self, line: &mut String, pb: &mut InsertionBuffer, fb: &mut InsertionBuffer);
+}
+
+pub struct StringSource {
+    text: String,
+    cursor: usize,
+}
+
+impl DataSource for StringSource {
+    fn reads_forward(&mut self, buffer: &mut InsertionBuffer) -> bool {
+        let max_read = (self.text.len() - self.cursor).min(buffer.capacity());
+        buffer.push_str(&self.text[self.cursor..self.cursor + max_read]);
+        self.cursor += max_read + 1;
+
+        self.cursor < self.text.len()
+    }
+    fn reads_backward(&mut self, buffer: &mut InsertionBuffer) -> bool {
+        let max_read = self.text.len().min(buffer.capacity());
+        buffer.push_str(&self.text[self.cursor..max_read]);
+        self.cursor += max_read + 1;
+
+        self.cursor != 0
+    }
+
+    fn readr_line(
+        &mut self,
+        line: &mut String,
+        pb: &mut InsertionBuffer,
+        fb: &mut InsertionBuffer,
+    ) {
+    }
+}
diff --git a/src/screen/mod.rs b/src/screen/mod.rs
@@ -7,17 +7,19 @@ use crate::{
 };
 #[cfg(feature = "search")]
 use regex::Regex;
-
+use smol_str::{SmolStr, ToSmolStr};
 use std::borrow::Cow;
 
+mod data_source;
+
 #[cfg(feature = "search")]
 use {crate::search, std::collections::BTreeSet};
 
 // |||||||||||||||||||||||||||||||||||||||||||||||||||||||
 //  TYPES TO BETTER DESCRIBE THE PURPOSE OF STRINGS
 // |||||||||||||||||||||||||||||||||||||||||||||||||||||||
-pub type Row = String;
-pub type Rows = Vec<String>;
+pub type Row = SmolStr;
+pub type Rows = Vec<SmolStr>;
 pub type Line<'a> = &'a str;
 pub type TextBlock<'a> = &'a str;
 pub type OwnedTextBlock = String;
@@ -149,7 +151,7 @@ impl Default for Screen {
         Self {
             line_wrapping: true,
             orig_text: String::with_capacity(100 * 1024),
-            formatted_lines: Vec::with_capacity(500 * 1024),
+            formatted_lines: Vec::with_capacity(10_000),
             line_count: 0,
             max_line_length: 0,
             unterminated: 0,
@@ -359,12 +361,8 @@ where
         to_format = opts.text.to_string();
     }
 
-    let lines = to_format
-        .lines()
-        .enumerate()
-        .collect::<Vec<(usize, &str)>>();
-
-    let to_format_size = lines.len();
+    let lines = to_format.lines().enumerate();
+    let to_format_size = calculate_format_sizr(&to_format);
 
     let mut fr = FormatResult {
         lines_formatted: to_format_size,
@@ -380,71 +378,47 @@ where
     let line_number_digits = minus_core::utils::digits(opts.lines_count + to_format_size);
 
     // Return if we have nothing to format
-    if lines.is_empty() {
+    if to_format_size == 0 {
         return fr;
     }
 
     // Number of rows that have been formatted so far
     // Whenever a line is formatted, this will be incremented to te number of rows that the formatted line has occupied
     let mut formatted_row_count = opts.formatted_lines_count;
 
-    {
-        let line_numbers = opts.line_numbers;
-        let cols = opts.cols;
-        let lines_count = opts.lines_count;
-        let line_wrapping = opts.line_wrapping;
-        #[cfg(feature = "search")]
-        let search_term = opts.search_term;
-
-        let rest_lines =
-            lines
-                .iter()
-                .take(lines.len().saturating_sub(1))
-                .flat_map(|(idx, line)| {
-                    let fmt_line = formatted_line(
-                        line,
-                        line_number_digits,
-                        lines_count + idx,
-                        line_numbers,
-                        cols,
-                        line_wrapping,
-                        #[cfg(feature = "search")]
-                        formatted_row_count,
-                        #[cfg(feature = "search")]
-                        &mut fr.append_search_idx,
-                        #[cfg(feature = "search")]
-                        search_term,
-                    );
-                    fr.lines_to_row_map.insert(formatted_row_count, true);
-                    formatted_row_count += fmt_line.len();
-                    if lines.len() > fr.max_line_length {
-                        fr.max_line_length = line.len();
-                    }
-
-                    fmt_line
-                });
-        opts.buffer.extend_buffer(rest_lines);
-    };
+    let line_numbers = opts.line_numbers;
+    let cols = opts.cols;
+    let lines_count = opts.lines_count;
+    let line_wrapping = opts.line_wrapping;
+    let mut last_line_row_span = 0;
+    #[cfg(feature = "search")]
+    let search_term = opts.search_term;
+
+    let formatted_lines = lines.flat_map(|(idx, line)| {
+        let fmt_line = formatted_line(
+            line,
+            line_number_digits,
+            lines_count + idx,
+            line_numbers,
+            cols,
+            line_wrapping,
+            #[cfg(feature = "search")]
+            formatted_row_count,
+            #[cfg(feature = "search")]
+            &mut fr.append_search_idx,
+            #[cfg(feature = "search")]
+            search_term,
+        );
+        fr.lines_to_row_map.insert(formatted_row_count, true);
+        formatted_row_count += fmt_line.len();
+        last_line_row_span = fmt_line.len();
+        if line.len() > fr.max_line_length {
+            fr.max_line_length = line.len();
+        }
 
-    let mut last_line = formatted_line(
-        lines.last().unwrap().1,
-        line_number_digits,
-        opts.lines_count + to_format_size - 1,
-        opts.line_numbers,
-        opts.cols,
-        opts.line_wrapping,
-        #[cfg(feature = "search")]
-        formatted_row_count,
-        #[cfg(feature = "search")]
-        &mut fr.append_search_idx,
-        #[cfg(feature = "search")]
-        opts.search_term,
-    );
-    fr.lines_to_row_map.insert(formatted_row_count, true);
-    formatted_row_count += last_line.len();
-    if lines.last().unwrap().1.len() > fr.max_line_length {
-        fr.max_line_length = lines.last().unwrap().1.len();
-    }
+        fmt_line
+    });
+    opts.buffer.extend_buffer(formatted_lines);
 
     #[cfg(feature = "search")]
     {
@@ -478,14 +452,20 @@ where
         // If the last line ends with \n, then the line is complete so nothing is left as unterminated
         0
     } else {
-        last_line.len()
+        last_line_row_span
     };
-    opts.buffer.append_to_buffer(&mut last_line);
     fr.rows_formatted = formatted_row_count - opts.formatted_lines_count;
 
     fr
 }
 
+fn calculate_format_sizr(text: &str) -> usize {
+    if text.is_empty() {
+        return 0;
+    }
+    bytecount::count(text.as_bytes(), b'\n') + usize::from(!text.ends_with('\n'))
+}
+
 /// Formats the given `line`
 ///
 /// - `line`: The line to format
@@ -568,7 +548,7 @@ pub(crate) fn formatted_line<'a>(
         // extra difficulty while writing tests
         // * Line number is added only to the first row of a line. This makes a better UI overall
         let formatter = |row: Cow<'_, str>, is_first_row: bool, idx: usize| {
-            format!(
+            smol_str::format_smolstr!(
                 "{bold}{number: >len$}{reset} {row}",
                 bold = if cfg!(not(test)) && is_first_row {
                     crossterm::style::Attribute::Bold.to_string()
@@ -615,9 +595,9 @@ pub(crate) fn formatted_line<'a>(
         enumerated_rows
             .map(|(wrap_idx, mut row)| {
                 handle_search(&mut row, wrap_idx);
-                row.to_string()
+                row.to_smolstr()
             })
-            .collect::<Vec<String>>()
+            .collect::<Vec<SmolStr>>()
     }
 }
 

diff --git a/src/search.rs b/src/search.rs
@@ -52,7 +52,7 @@
 
 #![allow(unused_imports)]
 use crate::minus_core::utils::{display, term};
-use crate::screen::Screen;
+use crate::screen::{Row, Screen};
 use crate::{error::MinusError, input::HashedEventRegister, screen};
 use crate::{LineNumbers, PagerState};
 use crossterm::{
@@ -242,7 +242,7 @@ impl FetchInputResult {
 /// A cache for storing all the new data obtained by running incremental search
 pub(crate) struct IncrementalSearchCache {
     /// Lines to be displayed with highlighted search matches
-    pub(crate) formatted_lines: Vec<String>,
+    pub(crate) formatted_lines: Vec<Row>,
     /// Index from `search_idx` where a search match after current upper mark may be found
     /// NOTE: There is no guarantee that this will stay within the bounds of `search_idx`
     pub(crate) search_mark: usize,

diff --git a/src/state.rs b/src/state.rs
@@ -398,3 +398,41 @@ impl PagerState {
         AppendStyle::PartialUpdate(fmt_lines)
     }
 }
+
+#[cfg(test)]
+mod bench {
+    extern crate test;
+    use super::PagerState;
+    use test::Bencher;
+
+    #[bench]
+    fn bench_append_str_chunks(b: &mut Bencher) {
+        let mut buffer = "This is a line\n".repeat(20);
+        // Remove the last \n from the text block
+        buffer.pop();
+
+        b.iter(|| {
+            for _ in 0..4_400_000 {
+                let mut ps = PagerState::new().unwrap();
+                ps.append_str(&buffer);
+            }
+        });
+    }
+
+    #[bench]
+    fn bench_append_str_big(b: &mut Bencher) {
+        let mut buffer = String::with_capacity(20 * 15 * 4_400_000);
+        let mut line = "This is a line\n".repeat(20);
+        // Remove the last \n from the text block
+        line.pop();
+
+        for _ in 0..4_400_000 {
+            buffer.push_str(&line);
+        }
+
+        b.iter(|| {
+            let mut ps = PagerState::new().unwrap();
+            ps.append_str(&buffer);
+        });
+    }
+}