Make decoration style non-optional

4 files changed, 77 insertions, 71 deletions

diff --git a/src/delta.rs b/src/delta.rs
index 86720418..0db2d2c6 100644
--- a/src/delta.rs
+++ b/src/delta.rs
@@ -5,7 +5,6 @@ use console::strip_ansi_codes;
 use std::io::BufRead;
 use unicode_segmentation::UnicodeSegmentation;
 
-use crate::cli::unreachable;
 use crate::config::Config;
 use crate::draw;
 use crate::paint::Painter;
@@ -191,25 +190,27 @@ fn handle_commit_meta_header_line(
     let decoration_ansi_term_style;
     let mut pad = false;
     let draw_fn = match config.commit_style.decoration_style {
-        Some(DecorationStyle::Box(style)) => {
+        DecorationStyle::Box(style) => {
             pad = true;
             decoration_ansi_term_style = style;
             draw::write_boxed_with_line
         }
-        Some(DecorationStyle::Underline(style)) => {
+        DecorationStyle::Underline(style) => {
             decoration_ansi_term_style = style;
             draw::write_underlined
         }
-        Some(DecorationStyle::Overline(style)) => {
+        DecorationStyle::Overline(style) => {
             decoration_ansi_term_style = style;
             draw::write_overlined
         }
-        Some(DecorationStyle::Underoverline(style)) => {
+        DecorationStyle::Underoverline(style) => {
             decoration_ansi_term_style = style;
             draw::write_underoverlined
         }
-        Some(DecorationStyle::NoDecoration) => return Ok(()),
-        None => unreachable("Unreachable code path reached in handle_commit_meta_header_line."),
+        DecorationStyle::NoDecoration => {
+            decoration_ansi_term_style = ansi_term::Style::new();
+            draw::write_no_decoration
+        }
     };
     draw_fn(
         painter.writer,
@@ -242,26 +243,26 @@ fn handle_generic_file_meta_header_line(
     let decoration_ansi_term_style;
     let mut pad = false;
     let draw_fn = match config.file_style.decoration_style {
-        Some(DecorationStyle::Box(style)) => {
+        DecorationStyle::Box(style) => {
             pad = true;
             decoration_ansi_term_style = style;
             draw::write_boxed_with_line
         }
-        Some(DecorationStyle::Underline(style)) => {
+        DecorationStyle::Underline(style) => {
             decoration_ansi_term_style = style;
             draw::write_underlined
         }
-        Some(DecorationStyle::Overline(style)) => {
+        DecorationStyle::Overline(style) => {
             decoration_ansi_term_style = style;
             draw::write_overlined
         }
-        Some(DecorationStyle::Underoverline(style)) => {
+        DecorationStyle::Underoverline(style) => {
             decoration_ansi_term_style = style;
             draw::write_underoverlined
         }
-        Some(DecorationStyle::NoDecoration) => return Ok(()),
-        None => {
-            unreachable("Unreachable code path reached in handle_generic_file_meta_header_line.")
+        DecorationStyle::NoDecoration => {
+            decoration_ansi_term_style = ansi_term::Style::new();
+            draw::write_no_decoration
         }
     };
     writeln!(painter.writer)?;
@@ -285,24 +286,26 @@ fn handle_hunk_header_line(
 ) -> std::io::Result<()> {
     let decoration_ansi_term_style;
     let draw_fn = match config.hunk_header_style.decoration_style {
-        Some(DecorationStyle::Box(style)) => {
+        DecorationStyle::Box(style) => {
             decoration_ansi_term_style = style;
             draw::write_boxed
         }
-        Some(DecorationStyle::Underline(style)) => {
+        DecorationStyle::Underline(style) => {
             decoration_ansi_term_style = style;
             draw::write_underlined
         }
-        Some(DecorationStyle::Overline(style)) => {
+        DecorationStyle::Overline(style) => {
             decoration_ansi_term_style = style;
             draw::write_overlined
         }
-        Some(DecorationStyle::Underoverline(style)) => {
+        DecorationStyle::Underoverline(style) => {
             decoration_ansi_term_style = style;
             draw::write_underoverlined
         }
-        Some(DecorationStyle::NoDecoration) => return Ok(()),
-        None => unreachable("Unreachable code path reached in handle_hunk_header_line."),
+        DecorationStyle::NoDecoration => {
+            decoration_ansi_term_style = ansi_term::Style::new();
+            draw::write_no_decoration
+        }
     };
     let (raw_code_fragment, line_number) = parse::parse_hunk_metadata(&line);
     let line = match prepare(raw_code_fragment, false, config) {
diff --git a/src/draw.rs b/src/draw.rs
index 67a15bb2..0dae0880 100644
--- a/src/draw.rs
+++ b/src/draw.rs
@@ -6,6 +6,17 @@ use box_drawing;
 use console::strip_ansi_codes;
 use unicode_width::UnicodeWidthStr;
 
+pub fn write_no_decoration(
+    writer: &mut dyn Write,
+    text: &str,
+    _line_width: usize, // ignored
+    _text_style: ansi_term::Style,
+    _decoration_style: ansi_term::Style,
+) -> std::io::Result<()> {
+    writeln!(writer, "{}", text)?;
+    Ok(())
+}
+
 /// Write text to stream, surrounded by a box, leaving the cursor just
 /// beyond the bottom right corner.
 pub fn write_boxed(
diff --git a/src/paint.rs b/src/paint.rs
index aa8aec4e..f200701d 100644
--- a/src/paint.rs
+++ b/src/paint.rs
@@ -400,7 +400,7 @@ mod superimpose_style_sections {
         use syntect::highlighting::FontStyle as SyntectFontStyle;
         use syntect::highlighting::Style as SyntectStyle;
 
-        use crate::style::Style;
+        use crate::style::{DecorationStyle, Style};
 
         lazy_static! {
             static ref SYNTAX_STYLE: SyntectStyle = SyntectStyle {
@@ -419,7 +419,7 @@ mod superimpose_style_sections {
                 },
                 is_raw: false,
                 is_syntax_highlighted: true,
-                decoration_style: None,
+                decoration_style: DecorationStyle::NoDecoration,
             };
         }
         lazy_static! {
@@ -432,7 +432,7 @@ mod superimpose_style_sections {
                 },
                 is_raw: false,
                 is_syntax_highlighted: false,
-                decoration_style: None,
+                decoration_style: DecorationStyle::NoDecoration,
             };
         }
         lazy_static! {
@@ -445,7 +445,7 @@ mod superimpose_style_sections {
                 },
                 is_raw: false,
                 is_syntax_highlighted: true,
-                decoration_style: None,
+                decoration_style: DecorationStyle::NoDecoration,
             };
         }
 
diff --git a/src/style.rs b/src/style.rs
index 75a08b82..05fa8655 100644
--- a/src/style.rs
+++ b/src/style.rs
@@ -10,7 +10,7 @@ pub struct Style {
     pub ansi_term_style: ansi_term::Style,
     pub is_raw: bool,
     pub is_syntax_highlighted: bool,
-    pub decoration_style: Option<DecorationStyle>,
+    pub decoration_style: DecorationStyle,
 }
 
 #[derive(Clone, Copy, Debug, PartialEq)]
@@ -28,7 +28,7 @@ impl Style {
             ansi_term_style: ansi_term::Style::new(),
             is_raw: false,
             is_syntax_highlighted: false,
-            decoration_style: None,
+            decoration_style: DecorationStyle::NoDecoration,
         }
     }
 
@@ -51,7 +51,7 @@ impl Style {
         );
         let decoration_style = match decoration_style_string {
             Some(s) if s != "" => DecorationStyle::from_str(s, true_color),
-            _ => None,
+            _ => DecorationStyle::NoDecoration,
         };
         Style {
             ansi_term_style,
@@ -79,13 +79,11 @@ impl Style {
             true_color,
         );
         if let Some(special_attribute) = special_attribute_from_style_string {
-            if let Some(decoration_style) = DecorationStyle::apply_special_decoration_attribute(
+            style.decoration_style = DecorationStyle::apply_special_decoration_attribute(
                 style.decoration_style,
                 &special_attribute,
                 true_color,
-            ) {
-                style.decoration_style = Some(decoration_style)
-            }
+            )
         }
         style
     }
@@ -115,23 +113,23 @@ impl Style {
                 .foreground;
             style.ansi_term_style.foreground = foreground_from_deprecated_arg;
             style.decoration_style = match style.decoration_style {
-                Some(DecorationStyle::Box(mut ansi_term_style)) => {
+                DecorationStyle::Box(mut ansi_term_style) => {
                     ansi_term_style.foreground = foreground_from_deprecated_arg;
-                    Some(DecorationStyle::Box(ansi_term_style))
+                    DecorationStyle::Box(ansi_term_style)
                 }
-                Some(DecorationStyle::Underline(mut ansi_term_style)) => {
+                DecorationStyle::Underline(mut ansi_term_style) => {
                     ansi_term_style.foreground = foreground_from_deprecated_arg;
-                    Some(DecorationStyle::Underline(ansi_term_style))
+                    DecorationStyle::Underline(ansi_term_style)
                 }
-                Some(DecorationStyle::Overline(mut ansi_term_style)) => {
+                DecorationStyle::Overline(mut ansi_term_style) => {
                     ansi_term_style.foreground = foreground_from_deprecated_arg;
-                    Some(DecorationStyle::Overline(ansi_term_style))
+                    DecorationStyle::Overline(ansi_term_style)
                 }
-                Some(DecorationStyle::Underoverline(mut ansi_term_style)) => {
+                DecorationStyle::Underoverline(mut ansi_term_style) => {
                     ansi_term_style.foreground = foreground_from_deprecated_arg;
-                    Some(DecorationStyle::Underoverline(ansi_term_style))
+                    DecorationStyle::Underoverline(ansi_term_style)
                 }
-                _ => style.decoration_style,
+                DecorationStyle::NoDecoration => style.decoration_style,
             };
         }
         style
@@ -139,17 +137,17 @@ impl Style {
 
     pub fn decoration_ansi_term_style(&self) -> Option<ansi_term::Style> {
         match self.decoration_style {
-            Some(DecorationStyle::Box(style)) => Some(style),
-            Some(DecorationStyle::Underline(style)) => Some(style),
-            Some(DecorationStyle::Overline(style)) => Some(style),
-            Some(DecorationStyle::Underoverline(style)) => Some(style),
-            _ => None,
+            DecorationStyle::Box(style) => Some(style),
+            DecorationStyle::Underline(style) => Some(style),
+            DecorationStyle::Overline(style) => Some(style),
+            DecorationStyle::Underoverline(style) => Some(style),
+            DecorationStyle::NoDecoration => None,
         }
     }
 }
 
 impl DecorationStyle {
-    pub fn from_str(style_string: &str, true_color: bool) -> Option<Self> {
+    pub fn from_str(style_string: &str, true_color: bool) -> Self {
         let (style_string, special_attribute) = extract_special_decoration_attribute(&style_string);
         let special_attribute = special_attribute.unwrap_or_else(|| {
             eprintln!(
@@ -170,41 +168,35 @@ impl DecorationStyle {
             process::exit(1);
         };
         match special_attribute.as_ref() {
-            "box" => Some(DecorationStyle::Box(style)),
-            "underline" => Some(DecorationStyle::Underline(style)),
-            "ul" => Some(DecorationStyle::Underline(style)),
-            "overline" => Some(DecorationStyle::Overline(style)),
-            "underoverline" => Some(DecorationStyle::Underoverline(style)),
-            "omit" => Some(DecorationStyle::NoDecoration),
-            "plain" => Some(DecorationStyle::NoDecoration),
+            "box" => DecorationStyle::Box(style),
+            "underline" => DecorationStyle::Underline(style),
+            "ul" => DecorationStyle::Underline(style),
+            "overline" => DecorationStyle::Overline(style),
+            "underoverline" => DecorationStyle::Underoverline(style),
+            "omit" => DecorationStyle::NoDecoration,
+            "plain" => DecorationStyle::NoDecoration,
             _ => unreachable("Unreachable code path reached in parse_decoration_style."),
         }
     }
 
     fn apply_special_decoration_attribute(
-        decoration_style: Option<DecorationStyle>,
+        decoration_style: DecorationStyle,
         special_attribute: &str,
         true_color: bool,
-    ) -> Option<DecorationStyle> {
+    ) -> DecorationStyle {
         let ansi_term_style = match decoration_style {
-            None => ansi_term::Style::new(),
-            Some(DecorationStyle::Box(ansi_term_style)) => ansi_term_style,
-            Some(DecorationStyle::Underline(ansi_term_style)) => ansi_term_style,
-            Some(DecorationStyle::Overline(ansi_term_style)) => ansi_term_style,
-            Some(DecorationStyle::Underoverline(ansi_term_style)) => ansi_term_style,
-            Some(DecorationStyle::NoDecoration) => ansi_term::Style::new(),
+            DecorationStyle::Box(ansi_term_style) => ansi_term_style,
+            DecorationStyle::Underline(ansi_term_style) => ansi_term_style,
+            DecorationStyle::Overline(ansi_term_style) => ansi_term_style,
+            DecorationStyle::Underoverline(ansi_term_style) => ansi_term_style,
+            DecorationStyle::NoDecoration => ansi_term::Style::new(),
         };
         match DecorationStyle::from_str(special_attribute, true_color) {
-            Some(DecorationStyle::Box(_)) => Some(DecorationStyle::Box(ansi_term_style)),
-            Some(DecorationStyle::Underline(_)) => {
-                Some(DecorationStyle::Underline(ansi_term_style))
-            }
-            Some(DecorationStyle::Overline(_)) => Some(DecorationStyle::Overline(ansi_term_style)),
-            Some(DecorationStyle::Underoverline(_)) => {
-                Some(DecorationStyle::Underoverline(ansi_term_style))
-            }
-            Some(DecorationStyle::NoDecoration) => Some(DecorationStyle::NoDecoration),
-            None => None,
+            DecorationStyle::Box(_) => DecorationStyle::Box(ansi_term_style),
+            DecorationStyle::Underline(_) => DecorationStyle::Underline(ansi_term_style),
+            DecorationStyle::Overline(_) => DecorationStyle::Overline(ansi_term_style),
+            DecorationStyle::Underoverline(_) => DecorationStyle::Underoverline(ansi_term_style),
+            DecorationStyle::NoDecoration => DecorationStyle::NoDecoration,
         }
     }
 }