Add omit_term_stderr config (#79)

To disable unnecessary backend terminal output to the stderr.

There are some annoying but harmless logs from kitty like:

"""
[0.201] The output buffer does not support sRGB color encoding, colors will be incorrect.
[0.321] [PARSE ERROR] Escape codes to resize text area are not supported
"""

which are printed all the time. See:
kovidgoyal/kitty#7409
kovidgoyal/kitty#8545

Just give user an option to disable the stderr output. The error log
will be disabled if the option is true and the log level is above
DEBUG.

(Have thought about adding a log filter to specific backend, but it
seems to be over-designed.)

Author: beeender

CHANGES.md

@@ -3,7 +3,7 @@ CHANGES
 
 Next Release
 
--
+- Add `omit_term_stderr` to the config to disable unnecessary backend terminal output to the stderr.
 
 1.5.0
 

config.yml

@@ -39,3 +39,6 @@
 # when 'load_term_conf' is true.
 #term_config_path: /path/to/config.toml
 
+# Set to true to redirect the backend terminal error output to null device.
+# Avoid annoying harmless terminal error logs being printed all the time.
+#omit_term_stderr: false

src/backend/alacritty.rs

@@ -193,15 +193,10 @@ mod tests {
     #[test]
     fn test_create_basic_alacritty_conf() {
         let conf = config::Config {
-            fork: false,
             backend: Some(config::Backend::Alacritty),
-            term_exe_path: None,
-            term_config_path: None,
-            exe_path: None,
-            nvim_exe_path: "nvim".to_owned(),
             font_size: 14,
             fonts: vec!["test_font".to_string()],
-            load_term_conf: false,
+            ..Default::default()
         };
         let mut alacritty = Alacritty {
             exe_path: PathBuf::new(),
@@ -232,15 +227,10 @@ bindings = [{ key = "Z", mods = "Control", action = "None" }]
         term_conf.insert("font", Item::Table(font_mapping));
 
         let conf = config::Config {
-            fork: false,
             backend: Some(config::Backend::Alacritty),
-            term_exe_path: None,
-            term_config_path: None,
-            exe_path: None,
-            nvim_exe_path: "nvim".to_owned(),
             font_size: 14,
             fonts: vec!["test_font".to_string()],
-            load_term_conf: false,
+            ..Default::default()
         };
         let mut alacritty = Alacritty {
             exe_path: PathBuf::new(),
@@ -270,17 +260,8 @@ bindings = [{ key = "Z", mods = "Control", action = "None" }]
         font_mapping.insert("size", value(42));
         term_conf.insert("font", Item::Table(font_mapping));
 
-        let conf = config::Config {
-            fork: false,
-            backend: Some(config::Backend::Alacritty),
-            term_exe_path: None,
-            term_config_path: None,
-            exe_path: None,
-            nvim_exe_path: "nvim".to_owned(),
-            font_size: 0,
-            fonts: vec![],
-            load_term_conf: false,
-        };
+        let mut conf = config::Config::default();
+        conf.backend = Some(config::Backend::Alacritty);
         let mut alacritty = Alacritty {
             exe_path: PathBuf::new(),
             cfg_file: None,
@@ -309,15 +290,8 @@ bindings = [{ key = "Z", mods = "Control", action = "None" }]
         term_conf.insert("colors", Item::Table(colors));
 
         let conf = config::Config {
-            fork: false,
             backend: Some(config::Backend::Alacritty),
-            term_exe_path: None,
-            term_config_path: None,
-            exe_path: None,
-            nvim_exe_path: "nvim".to_owned(),
-            font_size: 0,
-            fonts: vec![],
-            load_term_conf: false,
+            ..Default::default()
         };
         let mut alacritty = Alacritty {
             exe_path: PathBuf::new(),
@@ -352,15 +326,11 @@ size = 16
         w.write_all(term_conf.as_bytes()).ok();
         w.flush().expect("");
         let conf = config::Config {
-            fork: false,
             backend: Some(config::Backend::Alacritty),
-            term_exe_path: None,
             term_config_path: Some(term_conf_file.path().to_str().unwrap().to_string()),
-            exe_path: None,
-            nvim_exe_path: "nvim".to_owned(),
             font_size: 14,
             fonts: vec!["test_font".to_string()],
-            load_term_conf: false,
+            ..Default::default()
         };
         let mut alacritty = Alacritty {
             exe_path: PathBuf::new(),

src/config.rs

@@ -33,6 +33,8 @@ pub struct Config {
     pub fonts: Vec<String>,
     #[serde(default)]
     pub font_size: u8,
+    #[serde(default)]
+    pub omit_term_stderr: bool,
 }
 
 impl Default for Config {
@@ -47,6 +49,7 @@ impl Default for Config {
             fonts: Vec::new(),
             font_size: 0,
             load_term_conf: false,
+            omit_term_stderr: false,
         }
     }
 }
@@ -83,9 +86,13 @@ pub fn parse(path: PathBuf) -> Config {
     config
 }
 
-pub fn complete(mut config: Config, fork: bool) -> Config {
-    config.fork = fork;
-    config
+impl Config {
+    pub fn should_omit_stderr(&self) -> bool {
+        if log::log_enabled!(log::Level::Debug) {
+            return false;
+        }
+        self.omit_term_stderr
+    }
 }
 
 #[cfg(test)]

src/main.rs

@@ -8,7 +8,7 @@ mod error;
 
 use config::*;
 use std::env;
-use std::process::Command;
+use std::process::{Command, Stdio};
 use sysinfo::Pid;
 
 const DEFAULT_FONT_SIZE: u8 = 12;
@@ -75,7 +75,7 @@ fn parse_args() -> (Config, Vec<String>) {
         }
         None => Config::default(),
     };
-    config = config::complete(config, fork);
+    config.fork = fork;
     if !config.load_term_conf {
         // Set our default configs if user doesn't use the terminal's conf.
         if config.font_size == 0 {
@@ -159,6 +159,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     prepare_env();
     log::debug!("Start command: {:?}", command);
+    if config.should_omit_stderr() {
+        command.stderr(Stdio::null());
+    }
     let mut child = command.spawn()?;
 
     backend_functions.post_start(&config, Pid::from_u32(child.id()));