Add option to generate a default config file, fixes #870

README.md

@@ -485,6 +485,11 @@ non-default location of the configuration file:
 export BAT_CONFIG_PATH="/path/to/bat.conf"
 ```
 
+A default configuration file can be created with the `--generate-config-file` option.
+```bash
+bat --generate-config-file
+```
+
 ### Format
 
 The configuration file is a simple list of command line arguments. Use `bat --help` to see a full list of possible options and values. In addition, you can add comments by prepending a line with the `#` character.

src/bin/bat/clap_app.rs

@@ -370,6 +370,14 @@ pub fn build_app(interactive_output: bool) -> ClapApp<'static, 'static> {
                 .hidden(true)
                 .help("Show path to the configuration file."),
         )
+        .arg(
+            Arg::with_name("generate-config-file")
+                .long("generate-config-file")
+                .conflicts_with("list-languages")
+                .conflicts_with("list-themes")
+                .hidden(true)
+                .help("Generates a default configuration file."),
+        )
         .arg(
             Arg::with_name("config-dir")
                 .long("config-dir")

src/bin/bat/config.rs

@@ -1,6 +1,7 @@
 use std::env;
 use std::ffi::OsString;
 use std::fs;
+use std::io::{self, Write};
 use std::path::PathBuf;
 
 use shell_words;
@@ -15,6 +16,51 @@ pub fn config_file() -> PathBuf {
         .unwrap_or_else(|| PROJECT_DIRS.config_dir().join("config"))
 }
 
+pub fn generate_config_file() -> bat::errors::Result<()> {
+    let config_file = config_file();
+    if config_file.exists() {
+        println!("A config file already exists at: {}", config_file.to_string_lossy());
+
+        print!("Overwrite? (y/N): ");
+        io::stdout().flush()?;
+        let mut decision = String::new();
+        io::stdin().read_line(&mut decision)?;
+
+        if !decision.trim().eq_ignore_ascii_case("Y") {
+            return Ok(());
+        }
+    } else {
+        let config_dir = config_file.parent();
+        match config_dir {
+            Some(path) => fs::create_dir_all(path)?,
+            None => return Ok(Err(format!("Unable to write config file to: {}", config_file.to_string_lossy()))?),
+        }
+    }
+
+    let default_config = r#"# bat config
+
+# Specify desired theme (e.g. "TwoDark").  Issue `bat --list-themes` for a list of all available themes
+#--theme="TwoDark"
+
+# Enable this to use italic text on the terminal (not supported on all terminals):
+#--italic-text=always
+
+# Uncomment the following line to disable automatic paging:
+#--paging=never
+
+# Use C++ syntax for .ino files
+#--map-syntax "*.ino:C++"
+
+# Use ".gitignore"-style highlighting for ".ignore" files
+#--map-syntax ".ignore:Git Ignore"
+"#;
+
+    fs::write(&config_file, default_config)?;
+    println!("Success! Config file written to {}", config_file.to_string_lossy());
+
+    return Ok(());
+}
+
 pub fn get_args_from_config_file() -> Result<Vec<OsString>, shell_words::ParseError> {
     Ok(fs::read_to_string(config_file())
         .ok()

src/bin/bat/main.rs

@@ -22,7 +22,7 @@ use std::process;
 use ansi_term::Colour::Green;
 use ansi_term::Style;
 
-use crate::{app::App, config::config_file};
+use crate::{app::App, config::{config_file, generate_config_file}};
 use assets::{assets_from_cache_or_binary, cache_dir, clear_assets, config_dir};
 use bat::Controller;
 use directories::PROJECT_DIRS;
@@ -179,15 +179,15 @@ fn run() -> Result<bool> {
 
             if app.matches.is_present("list-languages") {
                 list_languages(&config)?;
-
                 Ok(true)
             } else if app.matches.is_present("list-themes") {
                 list_themes(&config)?;
-
                 Ok(true)
             } else if app.matches.is_present("config-file") {
                 println!("{}", config_file().to_string_lossy());
-
+                Ok(true)
+            } else if app.matches.is_present("generate-config-file") {
+                generate_config_file()?;
                 Ok(true)
             } else if app.matches.is_present("config-dir") {
                 writeln!(io::stdout(), "{}", config_dir())?;