fix: build cache output dir

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "silicon"
-version = "0.4.3"
+version = "0.5.0"
 description = "Create beautiful image of your code"
 authors = ["Aloxaf <aloxafx@gmail.com>"]
 categories = ["command-line-utilities"]

README.md

@@ -125,9 +125,10 @@ see `silicon --help` for detail
 
 ## Adding new syntaxes / themes
 
-Silicon reads syntax-definition and theme cache from bat's cache directory. 
+Silicon reads syntax-definition and theme cache from user's cache directory. 
 
-You can find the steps to add new syntaxes / themes for bat here: [sharkdp/bat#adding-new-syntaxes--language-definitions](https://github.com/sharkdp/bat#adding-new-syntaxes--language-definitions).
+The steps to add new syntaxes / themes is as same as bat: [sharkdp/bat#adding-new-syntaxes--language-definitions](https://github.com/sharkdp/bat#adding-new-syntaxes--language-definitions).
+Just replace `bat cache --build` to `silicon --build-cache`.
 
 ## Configuration file
 

src/assets.rs

@@ -39,9 +39,9 @@ impl HighlightingAssets {
         Ok(())
     }
 
-    pub fn dump_to_file(&self) -> Result<()> {
-        dumps::dump_to_file(&self.syntax_set, "./syntaxes.bin")?;
-        dumps::dump_to_file(&self.theme_set, "./themes.bin")?;
+    pub fn dump_to_file<P: AsRef<Path>>(&self, path: P) -> Result<()> {
+        dumps::dump_to_file(&self.syntax_set, path.as_ref().join("syntaxes.bin"))?;
+        dumps::dump_to_file(&self.theme_set, path.as_ref().join("themes.bin"))?;
         Ok(())
     }
 }

src/bin/silicon/config.rs

@@ -202,8 +202,8 @@ pub struct Config {
     // #[structopt(long)]
     // watermark: Option<String>,
     /// build syntax definition and theme cache
-    #[structopt(long)]
-    pub build_cache: Option<PathBuf>,
+    #[structopt(long, value_name = "OUTPUT_DIR")]
+    pub build_cache: Option<Option<PathBuf>>,
 }
 
 impl Config {

src/bin/silicon/main.rs

@@ -3,6 +3,7 @@ extern crate anyhow;
 
 use anyhow::Error;
 use image::DynamicImage;
+use std::env;
 use structopt::StructOpt;
 use syntect::easy::HighlightLines;
 use syntect::util::LinesWithEndings;
@@ -17,9 +18,9 @@ use {image::ImageOutputFormat, pasteboard::Pasteboard};
 use {image::ImageOutputFormat, std::process::Command};
 
 mod config;
-use crate::config::{config_file, get_args_from_config_file};
-use config::Config;
+use crate::config::{config_file, get_args_from_config_file, Config};
 use silicon::assets::HighlightingAssets;
+use silicon::directories::PROJECT_DIRS;
 
 #[cfg(target_os = "linux")]
 pub fn dump_image_to_clipboard(image: &DynamicImage) -> Result<(), Error> {
@@ -86,8 +87,12 @@ fn run() -> Result<(), Error> {
 
     if let Some(path) = config.build_cache {
         let mut ha = HighlightingAssets::new();
-        ha.add_from_folder(path)?;
-        ha.dump_to_file()?;
+        ha.add_from_folder(env::current_dir()?)?;
+        if let Some(path) = path {
+            ha.dump_to_file(path)?;
+        } else {
+            ha.dump_to_file(PROJECT_DIRS.cache_dir())?;
+        }
         return Ok(());
     } else if config.list_themes {
         for i in ts.themes.keys() {

src/directories.rs

@@ -1,5 +1,6 @@
 use lazy_static::lazy_static;
 use std::env;
+use std::fs::create_dir_all;
 use std::path::{Path, PathBuf};
 
 pub struct SiliconProjectDirs {
@@ -22,6 +23,9 @@ impl SiliconProjectDirs {
 
         let config_dir = config_dir_op.map(|d| d.join("silicon"))?;
 
+        create_dir_all(&config_dir).expect("cannot create config dir");
+        create_dir_all(&cache_dir).expect("cannot create cache dir");
+
         Some(Self {
             cache_dir,
             config_dir,