Move git changes support behind a feature

Cargo.toml

@@ -23,10 +23,12 @@ application = [
     "atty",
     "clap",
     "dirs",
+    "git",
     "lazy_static",
     "liquid",
     "wild",
 ]
+git = ["git2"] # Support indicating git modifications
 
 [dependencies]
 atty = { version = "0.2.14", optional = true }
@@ -44,6 +46,7 @@ globset = "0.4"
 
 [dependencies.git2]
 version = "0.13"
+optional = true
 default-features = false
 
 [dependencies.syntect]

ci/script.bash

@@ -15,3 +15,4 @@ fi
 
 # Check bat-as-a-library, which has a smaller set of dependencies
 cargo check --target "$TARGET" --verbose --lib --no-default-features
+cargo check --target "$TARGET" --verbose --lib --no-default-features --features git

src/decorations.rs

@@ -1,3 +1,4 @@
+#[cfg(feature = "git")]
 use crate::diff::LineChange;
 use crate::printer::{Colors, InteractivePrinter};
 use ansi_term::Style;
@@ -68,6 +69,7 @@ impl Decoration for LineNumberDecoration {
     }
 }
 
+#[cfg(feature = "git")]
 pub struct LineChangesDecoration {
     cached_none: DecorationText,
     cached_added: DecorationText,
@@ -76,6 +78,7 @@ pub struct LineChangesDecoration {
     cached_modified: DecorationText,
 }
 
+#[cfg(feature = "git")]
 impl LineChangesDecoration {
     #[inline]
     fn generate_cached(style: Style, text: &str) -> DecorationText {
@@ -96,6 +99,7 @@ impl LineChangesDecoration {
     }
 }
 
+#[cfg(feature = "git")]
 impl Decoration for LineChangesDecoration {
     fn generate(
         &self,

src/diff.rs

@@ -1,3 +1,5 @@
+#![cfg(feature = "git")]
+
 use std::collections::HashMap;
 use std::ffi::OsStr;
 use std::fs;

src/printer.rs

@@ -21,11 +21,11 @@ use unicode_width::UnicodeWidthChar;
 
 use crate::assets::HighlightingAssets;
 use crate::config::Config;
-use crate::decorations::{
-    Decoration, GridBorderDecoration, LineChangesDecoration, LineNumberDecoration,
-};
-use crate::diff::get_git_diff;
-use crate::diff::LineChanges;
+use crate::decorations::{Decoration, GridBorderDecoration, LineNumberDecoration};
+#[cfg(feature = "git")]
+use crate::decorations::LineChangesDecoration;
+#[cfg(feature = "git")]
+use crate::diff::{get_git_diff, LineChanges};
 use crate::errors::*;
 use crate::inputfile::{InputFile, InputFileReader};
 use crate::line_range::RangeCheckResult;
@@ -100,6 +100,7 @@ pub struct InteractivePrinter<'a> {
     panel_width: usize,
     ansi_prefix_sgr: String,
     content_type: Option<ContentType>,
+    #[cfg(feature = "git")]
     pub line_changes: Option<LineChanges>,
     highlighter: Option<HighlightLines<'a>>,
     syntax_set: &'a SyntaxSet,
@@ -130,8 +131,11 @@ impl<'a> InteractivePrinter<'a> {
             decorations.push(Box::new(LineNumberDecoration::new(&colors)));
         }
 
-        if config.style_components.changes() {
-            decorations.push(Box::new(LineChangesDecoration::new(&colors)));
+        #[cfg(feature = "git")]
+        {
+            if config.style_components.changes() {
+                decorations.push(Box::new(LineChangesDecoration::new(&colors)));
+            }
         }
 
         let mut panel_width: usize =
@@ -153,6 +157,7 @@ impl<'a> InteractivePrinter<'a> {
             panel_width = 0;
         }
 
+        #[cfg(feature = "git")]
         let mut line_changes = None;
 
         let highlighter = if reader
@@ -162,14 +167,14 @@ impl<'a> InteractivePrinter<'a> {
             None
         } else {
             // Get the Git modifications
-            line_changes = if config.style_components.changes() {
-                match file {
-                    InputFile::Ordinary(filename) => get_git_diff(filename),
-                    _ => None,
+            #[cfg(feature = "git")]
+            {
+                if config.style_components.changes() {
+                    if let InputFile::Ordinary(filename) = file {
+                        line_changes = get_git_diff(filename);
+                    }
                 }
-            } else {
-                None
-            };
+            }
 
             // Determine the type of syntax for highlighting
             let syntax = assets.get_syntax(config.language, file, reader, &config.syntax_mapping);
@@ -183,6 +188,7 @@ impl<'a> InteractivePrinter<'a> {
             decorations,
             content_type: reader.content_type,
             ansi_prefix_sgr: String::new(),
+            #[cfg(feature = "git")]
             line_changes,
             highlighter,
             syntax_set: &assets.syntax_set,

src/style.rs

@@ -68,6 +68,7 @@ impl StyleComponents {
         StyleComponents(components.iter().cloned().collect())
     }
 
+    #[cfg(feature = "git")]
     pub fn changes(&self) -> bool {
         self.0.contains(&StyleComponent::Changes)
     }