Make 'build-assets' an optional capability for application

Also structure features a bit more clever to avoid duplication of
feature dependency declarations.

src/assets.rs

@@ -4,13 +4,12 @@ use std::path::{Path, PathBuf};
 
 use lazycell::LazyCell;
 
-use syntect::dumps::{dump_to_file, from_binary, from_reader};
+use syntect::dumps::{from_binary, from_reader};
 use syntect::highlighting::{Theme, ThemeSet};
-use syntect::parsing::{SyntaxReference, SyntaxSet, SyntaxSetBuilder};
+use syntect::parsing::{SyntaxReference, SyntaxSet};
 
 use path_abs::PathAbs;
 
-use crate::assets_metadata::AssetsMetadata;
 use crate::bat_warning;
 use crate::error::*;
 use crate::input::{InputReader, OpenedInput, OpenedInputKind};
@@ -72,6 +71,7 @@ impl HighlightingAssets {
         "Monokai Extended"
     }
 
+    #[cfg(feature = "build-assets")]
     pub fn from_files(source_dir: &Path, include_integrated_assets: bool) -> Result<Self> {
         let mut theme_set = if include_integrated_assets {
             get_integrated_themeset()
@@ -97,11 +97,11 @@ impl HighlightingAssets {
         }
 
         let mut syntax_set_builder = if !include_integrated_assets {
-            let mut builder = SyntaxSetBuilder::new();
+            let mut builder = syntect::parsing::SyntaxSetBuilder::new();
             builder.add_plain_text_syntax();
             builder
         } else {
-            get_integrated_syntaxset().into_builder()
+            from_binary::<SyntaxSet>(get_serialized_integrated_syntaxset()).into_builder()
         };
 
         let syntax_dir = source_dir.join("syntaxes");
@@ -152,6 +152,7 @@ impl HighlightingAssets {
         )
     }
 
+    #[cfg(feature = "build-assets")]
     pub fn save_to_cache(&self, target_dir: &Path, current_version: &str) -> Result<()> {
         let _ = fs::create_dir_all(target_dir);
         asset_to_cache(
@@ -169,7 +170,7 @@ impl HighlightingAssets {
             "Writing metadata to folder {} ... ",
             target_dir.to_string_lossy()
         );
-        AssetsMetadata::new(current_version).save_to_folder(target_dir)?;
+        crate::assets_metadata::AssetsMetadata::new(current_version).save_to_folder(target_dir)?;
         println!("okay");
 
         Ok(())
@@ -416,17 +417,14 @@ fn get_serialized_integrated_syntaxset() -> &'static [u8] {
     include_bytes!("../assets/syntaxes.bin")
 }
 
-fn get_integrated_syntaxset() -> SyntaxSet {
-    from_binary(get_serialized_integrated_syntaxset())
-}
-
 fn get_integrated_themeset() -> ThemeSet {
     from_binary(include_bytes!("../assets/themes.bin"))
 }
 
+#[cfg(feature = "build-assets")]
 fn asset_to_cache<T: serde::Serialize>(asset: &T, path: &Path, description: &str) -> Result<()> {
     print!("Writing {} to {} ... ", description, path.to_string_lossy());
-    dump_to_file(asset, &path).chain_err(|| {
+    syntect::dumps::dump_to_file(asset, &path).chain_err(|| {
         format!(
             "Could not save {} to {}",
             description,

src/assets_metadata.rs

@@ -16,6 +16,7 @@ pub struct AssetsMetadata {
 const FILENAME: &str = "metadata.yaml";
 
 impl AssetsMetadata {
+    #[cfg(feature = "build-assets")]
     pub(crate) fn new(current_version: &str) -> AssetsMetadata {
         AssetsMetadata {
             bat_version: Some(current_version.to_owned()),
@@ -23,6 +24,7 @@ impl AssetsMetadata {
         }
     }
 
+    #[cfg(feature = "build-assets")]
     pub(crate) fn save_to_folder(&self, path: &Path) -> Result<()> {
         let file = File::create(path.join(FILENAME))?;
         serde_yaml::to_writer(file, self)?;

src/bin/bat/main.rs

@@ -23,12 +23,10 @@ use crate::{
 };
 
 use assets::{assets_from_cache_or_binary, cache_dir, clear_assets, config_dir};
-use clap::crate_version;
 use directories::PROJECT_DIRS;
 use globset::GlobMatcher;
 
 use bat::{
-    assets::HighlightingAssets,
     config::Config,
     controller::Controller,
     error::*,
@@ -39,21 +37,29 @@ use bat::{
 
 const THEME_PREVIEW_DATA: &[u8] = include_bytes!("../../../assets/theme_preview.rs");
 
+#[cfg(feature = "build-assets")]
+fn build_assets(matches: &clap::ArgMatches) -> Result<()> {
+    let source_dir = matches
+        .value_of("source")
+        .map(Path::new)
+        .unwrap_or_else(|| PROJECT_DIRS.config_dir());
+    let target_dir = matches
+        .value_of("target")
+        .map(Path::new)
+        .unwrap_or_else(|| PROJECT_DIRS.cache_dir());
+
+    let blank = matches.is_present("blank");
+
+    let assets = bat::assets::HighlightingAssets::from_files(source_dir, !blank)?;
+    assets.save_to_cache(target_dir, clap::crate_version!())
+}
+
 fn run_cache_subcommand(matches: &clap::ArgMatches) -> Result<()> {
     if matches.is_present("build") {
-        let source_dir = matches
-            .value_of("source")
-            .map(Path::new)
-            .unwrap_or_else(|| PROJECT_DIRS.config_dir());
-        let target_dir = matches
-            .value_of("target")
-            .map(Path::new)
-            .unwrap_or_else(|| PROJECT_DIRS.cache_dir());
-
-        let blank = matches.is_present("blank");
-
-        let assets = HighlightingAssets::from_files(source_dir, !blank)?;
-        assets.save_to_cache(target_dir, crate_version!())?;
+        #[cfg(feature = "build-assets")]
+        build_assets(matches)?;
+        #[cfg(not(feature = "build-assets"))]
+        println!("bat has been built without the 'build-assets' feature. The 'cache --build' option is not available.");
     } else if matches.is_present("clear") {
         clear_assets();
     }

src/config.rs

@@ -88,7 +88,7 @@ pub struct Config<'a> {
     pub use_custom_assets: bool,
 }
 
-#[cfg(all(feature = "application", feature = "paging"))]
+#[cfg(all(feature = "minimal-application", feature = "paging"))]
 pub fn get_pager_executable(config_pager: Option<&str>) -> Option<String> {
     if let Ok(Some(pager)) = crate::pager::get_pager(config_pager) {
         Some(pager.bin)

src/error.rs

@@ -3,7 +3,7 @@ use std::io::Write;
 
 error_chain! {
     foreign_links {
-        Clap(::clap::Error) #[cfg(feature = "application")];
+        Clap(::clap::Error) #[cfg(feature = "minimal-application")];
         Io(::std::io::Error);
         SyntectError(::syntect::LoadingError);
         ParseIntError(::std::num::ParseIntError);

src/lib.rs

@@ -40,6 +40,7 @@ mod preprocessor;
 mod pretty_printer;
 pub(crate) mod printer;
 pub mod style;
+#[cfg(feature = "build-assets")]
 mod syntax_dependencies;
 pub(crate) mod syntax_mapping;
 mod terminal;