Refactor: split file

1 files changed, 88 insertions, 321 deletions

diff --git a/src/parse.rs b/src/parse.rs
index a6e976ed..f41e4529 100644
--- a/src/parse.rs
+++ b/src/parse.rs
@@ -1,343 +1,110 @@
-use std::io::Write;
-
-use ansi_term::Colour::{Blue, Yellow};
-use console::strip_ansi_codes;
-
-use crate::bat::assets::HighlightingAssets;
-use crate::cli;
-use crate::draw;
-use crate::paint::{Config, Painter, NO_BACKGROUND_COLOR_STYLE_MODIFIER};
-use crate::parse::parse_git_diff::{
-    get_file_change_description_from_diff_line, get_file_extension_from_diff_line,
-    parse_hunk_metadata,
-};
-
-#[derive(Debug, PartialEq)]
-pub enum State {
-    CommitMeta, // In commit metadata section
-    FileMeta,   // In diff metadata section, between commit metadata and first hunk
-    HunkMeta,   // In hunk metadata line
-    HunkZero,   // In hunk; unchanged line
-    HunkMinus,  // In hunk; removed line
-    HunkPlus,   // In hunk; added line
-    Unknown,
-}
-
-impl State {
-    fn is_in_hunk(&self) -> bool {
-        match *self {
-            State::HunkMeta | State::HunkZero | State::HunkMinus | State::HunkPlus => true,
-            _ => false,
+use std::path::Path;
+
+/// Given input like
+/// "diff --git a/src/main.rs b/src/main.rs"
+/// Return "rs", i.e. a single file extension consistent with both files.
+pub fn get_file_extension_from_diff_line(line: &str) -> Option<&str> {
+    match get_file_extensions_from_diff_line(line) {
+        (Some(ext1), Some(ext2)) => {
+            if ext1 == ext2 {
+                Some(ext1)
+            } else {
+                // Unexpected: old and new files have different extensions.
+                None
+            }
         }
+        (Some(ext1), None) => Some(ext1),
+        (None, Some(ext2)) => Some(ext2),
+        (None, None) => None,
     }
 }
 
-// Possible transitions, with actions on entry:
-//
-//
-// | from \ to  | CommitMeta  | FileMeta    | HunkMeta    | HunkZero    | HunkMinus   | HunkPlus |
-// |------------+-------------+-------------+-------------+-------------+-------------+----------|
-// | CommitMeta | emit        | emit        |             |             |             |          |
-// | FileMeta   |             | emit        | emit        |             |             |          |
-// | HunkMeta   |             |             |             | emit        | push        | push     |
-// | HunkZero   | emit        | emit        | emit        | emit        | push        | push     |
-// | HunkMinus  | flush, emit | flush, emit | flush, emit | flush, emit | push        | push     |
-// | HunkPlus   | flush, emit | flush, emit | flush, emit | flush, emit | flush, push | push     |
-
-pub fn delta(
-    lines: impl Iterator<Item = String>,
-    config: &Config,
-    assets: &HighlightingAssets,
-    writer: &mut Write,
-) -> std::io::Result<()> {
-    // TODO: Painter::new(config)
-    let mut painter = Painter {
-        minus_lines: Vec::new(),
-        plus_lines: Vec::new(),
-        minus_line_style_sections: Vec::new(),
-        plus_line_style_sections: Vec::new(),
-        output_buffer: String::new(),
-        writer: writer,
-        syntax: None,
-        config: config,
-    };
-
-    let mut state = State::Unknown;
-
-    for raw_line in lines {
-        let line = strip_ansi_codes(&raw_line).to_string();
-        if line.starts_with("commit") {
-            painter.paint_buffered_lines();
-            state = State::CommitMeta;
-            if config.opt.commit_style != cli::SectionStyle::Plain {
-                painter.emit()?;
-                write_commit_meta_header_line(&mut painter, &raw_line, config)?;
-                continue;
-            }
-        } else if line.starts_with("diff --") {
-            painter.paint_buffered_lines();
-            state = State::FileMeta;
-            painter.syntax = match get_file_extension_from_diff_line(&line) {
-                Some(extension) => assets.syntax_set.find_syntax_by_extension(extension),
-                None => None,
-            };
-            if config.opt.file_style != cli::SectionStyle::Plain {
-                painter.emit()?;
-                write_file_meta_header_line(&mut painter, &raw_line, config)?;
-                continue;
-            }
-        } else if line.starts_with("@@") {
-            state = State::HunkMeta;
-            if config.opt.hunk_style != cli::SectionStyle::Plain {
-                painter.emit()?;
-                write_hunk_meta_line(&mut painter, &line, config)?;
-                continue;
-            }
-        } else if state.is_in_hunk() && painter.syntax.is_some() {
-            state = paint_hunk_line(state, &mut painter, &line, config);
-            painter.emit()?;
-            continue;
-        }
-        if state == State::FileMeta && config.opt.file_style != cli::SectionStyle::Plain {
-            // The file metadata section is 4 lines. Skip them under non-plain file-styles.
-            continue;
-        } else {
-            painter.emit()?;
-            writeln!(painter.writer, "{}", raw_line)?;
-        }
+// TODO: Don't parse the line twice (once for change description and once for extensions).
+pub fn get_file_change_description_from_diff_line(line: &str) -> String {
+    match get_file_paths_from_diff_line(line) {
+        (Some(file_1), Some(file_2)) if file_1 == file_2 => format!("{}", file_1),
+        (Some(file), Some("/dev/null")) => format!("deleted: {}", file),
+        (Some("/dev/null"), Some(file)) => format!("added: {}", file),
+        (Some(file_1), Some(file_2)) => format!("renamed: {} ⟶  {}", file_1, file_2),
+        _ => format!("?"),
     }
-
-    painter.paint_buffered_lines();
-    painter.emit()?;
-    Ok(())
 }
 
-fn write_commit_meta_header_line(
-    painter: &mut Painter,
-    line: &str,
-    config: &Config,
-) -> std::io::Result<()> {
-    let draw_fn = match config.opt.commit_style {
-        cli::SectionStyle::Box => draw::write_boxed_with_line,
-        cli::SectionStyle::Underline => draw::write_underlined,
-        cli::SectionStyle::Plain => panic!(),
-    };
-    draw_fn(
-        painter.writer,
-        line,
-        config.terminal_width,
-        Yellow.normal(),
-        true,
-    )?;
-    Ok(())
+/// Given input like
+/// "@@ -74,15 +74,14 @@ pub fn delta("
+/// Return " pub fn delta("
+pub fn parse_hunk_metadata(line: &str) -> (String, String) {
+    let mut iter = line.split("@@").skip(1);
+    let line_number = iter
+        .next()
+        .and_then(|s| {
+            s.split("+")
+                .skip(1)
+                .next()
+                .and_then(|s| s.split(",").next())
+        })
+        .unwrap_or("")
+        .to_string();
+    let code_fragment = iter.next().unwrap_or("").to_string();
+    (code_fragment, line_number)
 }
 
-fn write_file_meta_header_line(
-    painter: &mut Painter,
-    line: &str,
-    config: &Config,
-) -> std::io::Result<()> {
-    let draw_fn = match config.opt.file_style {
-        cli::SectionStyle::Box => draw::write_boxed_with_line,
-        cli::SectionStyle::Underline => draw::write_underlined,
-        cli::SectionStyle::Plain => panic!(),
-    };
-    let ansi_style = Blue.bold();
-    draw_fn(
-        painter.writer,
-        &ansi_style.paint(get_file_change_description_from_diff_line(&line)),
-        config.terminal_width,
-        ansi_style,
-        true,
-    )?;
-    Ok(())
+fn get_file_paths_from_diff_line(line: &str) -> (Option<&str>, Option<&str>) {
+    let mut iter = line.split(" ");
+    iter.next(); // diff
+    iter.next(); // --git
+    (
+        iter.next().and_then(|s| Some(&s[2..])),
+        iter.next().and_then(|s| Some(&s[2..])),
+    )
 }
 
-fn write_hunk_meta_line(painter: &mut Painter, line: &str, config: &Config) -> std::io::Result<()> {
-    let draw_fn = match config.opt.hunk_style {
-        cli::SectionStyle::Box => draw::write_boxed,
-        cli::SectionStyle::Underline => draw::write_underlined,
-        cli::SectionStyle::Plain => panic!(),
-    };
-    let ansi_style = Blue.normal();
-    let (code_fragment, line_number) = parse_hunk_metadata(&line);
-    if code_fragment.len() > 0 {
-        painter.paint_lines(
-            vec![code_fragment.clone()],
-            vec![vec![(
-                NO_BACKGROUND_COLOR_STYLE_MODIFIER,
-                code_fragment.clone(),
-            )]],
-        );
-        painter.output_buffer.pop(); // trim newline
-        draw_fn(
-            painter.writer,
-            &painter.output_buffer,
-            config.terminal_width,
-            ansi_style,
-            false,
-        )?;
-        painter.output_buffer.truncate(0);
-    }
-    writeln!(painter.writer, "\n{}", ansi_style.paint(line_number))?;
-    Ok(())
+/// Given input like "diff --git a/src/main.rs b/src/main.rs"
+/// return ("rs", "rs").
+fn get_file_extensions_from_diff_line(line: &str) -> (Option<&str>, Option<&str>) {
+    let mut iter = line.split(" ");
+    iter.next(); // diff
+    iter.next(); // --git
+    (
+        iter.next().and_then(|s| get_extension(&s[2..])),
+        iter.next().and_then(|s| get_extension(&s[2..])),
+    )
 }
 
-fn paint_hunk_line(state: State, painter: &mut Painter, line: &str, config: &Config) -> State {
-    match line.chars().next() {
-        Some('-') => {
-            if state == State::HunkPlus {
-                painter.paint_buffered_lines();
-            }
-            painter.minus_lines.push(prepare(&line, config));
-            State::HunkMinus
-        }
-        Some('+') => {
-            painter.plus_lines.push(prepare(&line, config));
-            State::HunkPlus
-        }
-        _ => {
-            painter.paint_buffered_lines();
-            let line = prepare(&line, config);
-            painter.paint_lines(
-                vec![line.clone()],
-                vec![vec![(NO_BACKGROUND_COLOR_STYLE_MODIFIER, line.clone())]],
-            );
-            State::HunkZero
-        }
-    }
+/// Attempt to parse input as a file path and return extension as a &str.
+fn get_extension(s: &str) -> Option<&str> {
+    let path = Path::new(s);
+    path.extension()
+        .and_then(|e| e.to_str())
+        // E.g. 'Makefile' is the file name and also the extension
+        .or_else(|| path.file_name().and_then(|s| s.to_str()))
 }
 
-/// Replace initial -/+ character with ' ' and pad to width.
-fn prepare(_line: &str, config: &Config) -> String {
-    let mut line = String::new();
-    if _line.len() > 0 {
-        line.push_str(" ");
-        line.push_str(&_line[1..]);
-    }
-    match config.width {
-        Some(width) => {
-            if line.len() < width {
-                line = format!("{}{}", line, " ".repeat(width - line.len()));
-            }
-        }
-        _ => (),
-    }
-    line
-}
-
-mod parse_git_diff {
-    use std::path::Path;
-
-    /// Given input like
-    /// "diff --git a/src/main.rs b/src/main.rs"
-    /// Return "rs", i.e. a single file extension consistent with both files.
-    pub fn get_file_extension_from_diff_line(line: &str) -> Option<&str> {
-        match get_file_extensions_from_diff_line(line) {
-            (Some(ext1), Some(ext2)) => {
-                if ext1 == ext2 {
-                    Some(ext1)
-                } else {
-                    // Unexpected: old and new files have different extensions.
-                    None
-                }
-            }
-            (Some(ext1), None) => Some(ext1),
-            (None, Some(ext2)) => Some(ext2),
-            (None, None) => None,
-        }
-    }
-
-    // TODO: Don't parse the line twice (once for change description and once for extensions).
-    pub fn get_file_change_description_from_diff_line(line: &str) -> String {
-        match get_file_paths_from_diff_line(line) {
-            (Some(file_1), Some(file_2)) if file_1 == file_2 => format!("{}", file_1),
-            (Some(file), Some("/dev/null")) => format!("deleted: {}", file),
-            (Some("/dev/null"), Some(file)) => format!("added: {}", file),
-            (Some(file_1), Some(file_2)) => format!("renamed: {} ⟶  {}", file_1, file_2),
-            _ => format!("?"),
-        }
-    }
-
-    /// Given input like
-    /// "@@ -74,15 +74,14 @@ pub fn delta("
-    /// Return " pub fn delta("
-    pub fn parse_hunk_metadata(line: &str) -> (String, String) {
-        let mut iter = line.split("@@").skip(1);
-        let line_number = iter
-            .next()
-            .and_then(|s| {
-                s.split("+")
-                    .skip(1)
-                    .next()
-                    .and_then(|s| s.split(",").next())
-            })
-            .unwrap_or("")
-            .to_string();
-        let code_fragment = iter.next().unwrap_or("").to_string();
-        (code_fragment, line_number)
-    }
+#[cfg(test)]
+mod tests {
+    use super::*;
 
-    fn get_file_paths_from_diff_line(line: &str) -> (Option<&str>, Option<&str>) {
-        let mut iter = line.split(" ");
-        iter.next(); // diff
-        iter.next(); // --git
-        (
-            iter.next().and_then(|s| Some(&s[2..])),
-            iter.next().and_then(|s| Some(&s[2..])),
-        )
-    }
-
-    /// Given input like "diff --git a/src/main.rs b/src/main.rs"
-    /// return ("rs", "rs").
-    fn get_file_extensions_from_diff_line(line: &str) -> (Option<&str>, Option<&str>) {
-        let mut iter = line.split(" ");
-        iter.next(); // diff
-        iter.next(); // --git
-        (
-            iter.next().and_then(|s| get_extension(&s[2..])),
-            iter.next().and_then(|s| get_extension(&s[2..])),
-        )
+    #[test]
+    fn test_get_file_extension_from_diff_line() {
+        assert_eq!(
+            get_file_extension_from_diff_line("diff --git a/src/main.rs b/src/main.rs"),
+            Some("rs")
+        );
     }
 
-    /// Attempt to parse input as a file path and return extension as a &str.
-    fn get_extension(s: &str) -> Option<&str> {
-        let path = Path::new(s);
-        path.extension()
-            .and_then(|e| e.to_str())
-            // E.g. 'Makefile' is the file name and also the extension
-            .or_else(|| path.file_name().and_then(|s| s.to_str()))
+    #[test]
+    fn test_get_file_change_description_from_diff_line() {
+        assert_eq!(
+            get_file_change_description_from_diff_line("diff --git a/src/main.rs b/src/main.rs"),
+            "src/main.rs"
+        );
     }
 
-    #[cfg(test)]
-    mod tests {
-        use super::*;
-
-        #[test]
-        fn test_get_file_extension_from_diff_line() {
-            assert_eq!(
-                get_file_extension_from_diff_line("diff --git a/src/main.rs b/src/main.rs"),
-                Some("rs")
-            );
-        }
-
-        #[test]
-        fn test_get_file_change_description_from_diff_line() {
-            assert_eq!(
-                get_file_change_description_from_diff_line(
-                    "diff --git a/src/main.rs b/src/main.rs"
-                ),
-                "src/main.rs"
-            );
-        }
-
-        #[test]
-        fn test_parse_hunk_metadata() {
-            assert_eq!(
-                parse_hunk_metadata("@@ -74,15 +75,14 @@ pub fn delta(\n"),
-                (" pub fn delta(\n".to_string(), "75".to_string())
-            );
-        }
+    #[test]
+    fn test_parse_hunk_metadata() {
+        assert_eq!(
+            parse_hunk_metadata("@@ -74,15 +75,14 @@ pub fn delta(\n"),
+            (" pub fn delta(\n".to_string(), "75".to_string())
+        );
     }
-
 }