Just straight-up roll our own logger

This commit removes the env_logger dependency, replacing it with a simple implementation. Doing so removes like ten other transitive dependencies that no longer need to be included in the build.

It also gains the ability to enable trace-level logging. The users crate, which contains such logging statements as of the version I published a few days ago, has been upgraded to celebrate.

Also, change the log imports to globs. I'm only interested that a file doing logging, not what level it's logging at.

Cargo.lock

@@ -1,14 +1,5 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-[[package]]
-name = "aho-corasick"
-version = "0.7.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "36b7aa1ccb7d7ea3f437cf025a2ab1c47cc6c1bc9fc84918ff449def12f5e282"
-dependencies = [
- "memchr",
-]
-
 [[package]]
 name = "ansi_term"
 version = "0.12.0"
@@ -18,16 +9,6 @@ dependencies = [
  "winapi 0.3.8",
 ]
 
-[[package]]
-name = "atty"
-version = "0.2.13"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1803c647a3ec87095e7ae7acfca019e98de5ec9a7d01343f611cf3152ed71a90"
-dependencies = [
- "libc",
- "winapi 0.3.8",
-]
-
 [[package]]
 name = "autocfg"
 version = "0.1.5"
@@ -73,26 +54,12 @@ dependencies = [
  "winapi 0.3.8",
 ]
 
-[[package]]
-name = "env_logger"
-version = "0.6.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aafcde04e90a5226a6443b7aabdb016ba2f8307c847d524724bd9b346dd1a2d3"
-dependencies = [
- "atty",
- "humantime",
- "log",
- "regex",
- "termcolor",
-]
-
 [[package]]
 name = "exa"
 version = "0.9.0"
 dependencies = [
  "ansi_term",
  "datetime",
- "env_logger",
  "git2",
  "glob",
  "lazy_static",
@@ -130,15 +97,6 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b919933a397b79c37e33b77bb2aa3dc8eb6e165ad809e58ff75bc7db2e34574"
 
-[[package]]
-name = "humantime"
-version = "1.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3ca7e5f2e110db35f93b837c81797f3714500b81d517bf20c431b16d3ca4f114"
-dependencies = [
- "quick-error",
-]
-
 [[package]]
 name = "idna"
 version = "0.1.5"
@@ -319,40 +277,12 @@ version = "0.3.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "676e8eb2b1b4c9043511a9b7bea0915320d7e502b0a079fb03f9635a5252b18c"
 
-[[package]]
-name = "quick-error"
-version = "1.2.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9274b940887ce9addde99c4eee6b5c44cc494b182b97e73dc8ffdcb3397fd3f0"
-
 [[package]]
 name = "redox_syscall"
 version = "0.1.56"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2439c63f3f6139d1b57529d16bc3b8bb855230c8efcc5d3a896c8bea7c3b1e84"
 
-[[package]]
-name = "regex"
-version = "1.1.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d9d8297cc20bbb6184f8b45ff61c8ee6a9ac56c156cec8e38c3e5084773c44ad"
-dependencies = [
- "aho-corasick",
- "memchr",
- "regex-syntax",
- "thread_local",
- "utf8-ranges",
-]
-
-[[package]]
-name = "regex-syntax"
-version = "0.6.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9b01330cce219c1c6b2e209e5ed64ccd587ae5c67bed91c0b49eecf02ae40e21"
-dependencies = [
- "ucd-util",
-]
-
 [[package]]
 name = "scoped_threadpool"
 version = "0.1.9"
@@ -385,30 +315,6 @@ dependencies = [
  "winapi 0.2.8",
 ]
 
-[[package]]
-name = "termcolor"
-version = "1.0.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "96d6098003bde162e4277c70665bd87c326f5a0c3f3fbfb285787fa482d54e6e"
-dependencies = [
- "wincolor",
-]
-
-[[package]]
-name = "thread_local"
-version = "0.3.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c6b53e329000edc2b34dbe8545fd20e55a333362d0a321909685a19bd28c3f1b"
-dependencies = [
- "lazy_static",
-]
-
-[[package]]
-name = "ucd-util"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "535c204ee4d8434478593480b8f86ab45ec9aae0e83c568ca81abf0fd0e88f86"
-
 [[package]]
 name = "unicode-bidi"
 version = "0.3.4"
@@ -446,20 +352,14 @@ dependencies = [
 
 [[package]]
 name = "users"
-version = "0.10.0"
+version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aa4227e95324a443c9fcb06e03d4d85e91aabe9a5a02aa818688b6918b6af486"
+checksum = "24cc0f6d6f267b73e5a2cadf007ba8f9bc39c6a6f9666f8cf25ea809a153b032"
 dependencies = [
  "libc",
  "log",
 ]
 
-[[package]]
-name = "utf8-ranges"
-version = "1.0.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9d50aa7650df78abf942826607c62468ce18d9019673d4a2ebe1865dbb96ffde"
-
 [[package]]
 name = "vcpkg"
 version = "0.2.7"
@@ -500,31 +400,12 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
 
-[[package]]
-name = "winapi-util"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7168bab6e1daee33b4557efd0e95d5ca70a03706d39fa5f3fe7a236f584b03c9"
-dependencies = [
- "winapi 0.3.8",
-]
-
 [[package]]
 name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
-[[package]]
-name = "wincolor"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "561ed901ae465d6185fa7864d63fbd5720d0ef718366c9a4dc83cf6170d7e9ba"
-dependencies = [
- "winapi 0.3.8",
- "winapi-util",
-]
-
 [[package]]
 name = "zoneinfo_compiled"
 version = "0.5.0"

Cargo.toml

@@ -24,7 +24,6 @@ name = "exa"
 [dependencies]
 ansi_term = "0.12.0"
 datetime = "0.5"
-env_logger = "0.6.1"
 glob = "0.3.0"
 lazy_static = "1.3.0"
 libc = "0.2.51"
@@ -37,7 +36,7 @@ scoped_threadpool = "0.1.9"
 term_grid = "0.1.7"
 term_size = "0.3.1"
 unicode-width = "0.1.5"
-users = "0.10"
+users = "0.11"
 zoneinfo_compiled = "0.5"
 
 [dependencies.git2]

devtools/dev-bash.sh

@@ -12,7 +12,7 @@ bash /vagrant/devtools/dev-versions.sh
 # The Cool Prompt tells you whether you’re in debug or strict mode, whether
 # you have colours configured, and whether your last command failed.
 function nonzero_return() { RETVAL=$?; [ $RETVAL -ne 0 ] && echo "$RETVAL "; }
-function debug_mode()  { [ -n "$EXA_DEBUG" ]  && echo "debug "; }
+function debug_mode()  { [ "$EXA_DEBUG" == "trace" ] && echo -n "trace-"; [ -n "$EXA_DEBUG" ]  && echo "debug "; }
 function strict_mode() { [ -n "$EXA_STRICT" ] && echo "strict "; }
 function lsc_mode()    { [ -n "$LS_COLORS" ]  && echo "lsc "; }
 function exac_mode()   { [ -n "$EXA_COLORS" ] && echo "exac "; }
@@ -22,10 +22,14 @@ export PS1="\[\e[1;36m\]\h \[\e[32m\]\w \[\e[31m\]\`nonzero_return\`\[\e[35m\]\`
 # The ‘debug’ function lets you switch debug mode on and off.
 # Turn it on if you need to see exa’s debugging logs.
 function debug () {
-  case "$1" in "on") export EXA_DEBUG=1 ;;
-    "off") export EXA_DEBUG= ;;
-    "")    [ -n "$EXA_DEBUG" ] && echo "debug on" || echo "debug off" ;;
-    *)     echo "Usage: debug on|off"; return 1 ;; esac; }
+  case "$1" in
+    ""|"on")  export EXA_DEBUG=1 ;;
+    "off")    export EXA_DEBUG= ;;
+    "trace")  export EXA_DEBUG=trace ;;
+    "status") [ -n "$EXA_DEBUG" ] && echo "debug on" || echo "debug off" ;;
+    *)        echo "Usage: debug on|off|trace|status"; return 1 ;;
+  esac;
+}
 
 # The ‘strict’ function lets you switch strict mode on and off.
 # Turn it on if you’d like exa’s command-line arguments checked.
@@ -33,7 +37,9 @@ function strict () {
   case "$1" in "on") export EXA_STRICT=1 ;;
     "off") export EXA_STRICT= ;;
     "") [ -n "$EXA_STRICT" ] && echo "strict on" || echo "strict off" ;;
-    *) echo "Usage: strict on|off"; return 1 ;; esac; }
+    *) echo "Usage: strict on|off"; return 1 ;;
+  esac;
+}
 
 # The ‘colors’ function sets or unsets the ‘LS_COLORS’ and ‘EXA_COLORS’
 # environment variables. There’s also a ‘hacker’ theme which turns everything
@@ -53,4 +59,6 @@ function colors () {
     "")
       [ -n "$LS_COLORS" ]  && echo "LS_COLORS=$LS_COLORS"   || echo "ls-colors off"
       [ -n "$EXA_COLORS" ] && echo "EXA_COLORS=$EXA_COLORS" || echo "exa-colors off" ;;
-    *) echo "Usage: ls-colors ls|hacker|off"; return 1 ;; esac; }
+    *) echo "Usage: ls-colors ls|hacker|off"; return 1 ;;
+  esac;
+}

src/fs/dir.rs

@@ -5,7 +5,7 @@ use std::fs;
 use std::path::{Path, PathBuf};
 use std::slice::Iter as SliceIter;
 
-use log::info;
+use log::*;
 
 use crate::fs::File;
 

src/fs/feature/git.rs

@@ -3,7 +3,7 @@
 use std::path::{Path, PathBuf};
 use std::sync::Mutex;
 
-use log::{debug, error, info, warn};
+use log::*;
 
 use crate::fs::fields as f;
 

src/fs/file.rs

@@ -6,7 +6,7 @@ use std::os::unix::fs::{MetadataExt, PermissionsExt, FileTypeExt};
 use std::path::{Path, PathBuf};
 use std::time::{Duration, SystemTime, UNIX_EPOCH};
 
-use log::{debug, error};
+use log::*;
 
 use crate::fs::dir::Dir;
 use crate::fs::fields as f;

src/logger.rs

@@ -0,0 +1,66 @@
+//! Debug error logging.
+
+use std::ffi::OsStr;
+
+use ansi_term::{Colour, ANSIString};
+
+
+/// Sets the internal logger, changing the log level based on the value of an
+/// environment variable.
+pub fn configure<T: AsRef<OsStr>>(ev: Option<T>) {
+    let ev = match ev {
+        Some(v)  => v,
+        None     => return,
+    };
+
+    let env_var = ev.as_ref();
+    if env_var.is_empty() {
+        return;
+    }
+
+    if env_var == "trace" {
+        log::set_max_level(log::LevelFilter::Trace);
+    }
+    else {
+        log::set_max_level(log::LevelFilter::Debug);
+    }
+
+    let result = log::set_logger(GLOBAL_LOGGER);
+    if let Err(e) = result {
+        eprintln!("Failed to initialise logger: {}", e);
+    }
+}
+
+
+#[derive(Debug)]
+struct Logger;
+
+const GLOBAL_LOGGER: &Logger = &Logger;
+
+impl log::Log for Logger {
+    fn enabled(&self, _: &log::Metadata<'_>) -> bool {
+        true  // no need to filter after using ‘set_max_level’.
+    }
+
+    fn log(&self, record: &log::Record<'_>) {
+        let open = Colour::Fixed(243).paint("[");
+        let level = level(record.level());
+        let close = Colour::Fixed(243).paint("]");
+
+        eprintln!("{}{} {}{} {}", open, level, record.target(), close, record.args());
+    }
+
+    fn flush(&self) {
+        // no need to flush with ‘eprintln!’.
+    }
+}
+
+fn level(level: log::Level) -> ANSIString<'static> {
+    match level {
+        log::Level::Error => Colour::Red.paint("ERROR"),
+        log::Level::Warn  => Colour::Yellow.paint("WARN"),
+        log::Level::Info  => Colour::Cyan.paint("INFO"),
+        log::Level::Debug => Colour::Blue.paint("DEBUG"),
+        log::Level::Trace => Colour::Fixed(245).paint("TRACE"),
+    }
+}

src/main.rs

@@ -8,7 +8,7 @@ use std::path::{Component, PathBuf};
 
 use ansi_term::{ANSIStrings, Style};
 
-use log::debug;
+use log::*;
 
 use crate::fs::{Dir, File};
 use crate::fs::filter::GitIgnore;
@@ -20,6 +20,7 @@ use crate::output::{escape, lines, grid, grid_details, details, View, Mode};
 
 mod fs;
 mod info;
+mod logger;
 mod options;
 mod output;
 mod style;
@@ -28,7 +29,7 @@ mod style;
 fn main() {
     use std::process::exit;
 
-    configure_logger();
+    logger::configure(env::var_os(vars::EXA_DEBUG));
 
     let args: Vec<OsString> = env::args_os().skip(1).collect();
     match Exa::from_args(args.iter(), &mut stdout()) {
@@ -66,34 +67,6 @@ fn main() {
 }
 
 
-/// Sets up a global logger if one is asked for.
-/// The ‘EXA_DEBUG’ environment variable controls whether log messages are
-/// displayed or not. Currently there are just two settings (on and off).
-///
-/// This can’t be done in exa’s own option parsing because that part of it
-/// logs as well, so by the time execution gets there, the logger needs to
-/// have already been set up.
-pub fn configure_logger() {
-    extern crate env_logger;
-    extern crate log;
-
-    let present = match env::var_os(vars::EXA_DEBUG) {
-        Some(debug)  => debug.len() > 0,
-        None         => false,
-    };
-
-    let mut logs = env_logger::Builder::new();
-    if present {
-        logs.filter(None, log::LevelFilter::Debug);
-    }
-    else {
-        logs.filter(None, log::LevelFilter::Off);
-    }
-
-    logs.init()
-}
-
-
 /// The main program wrapper.
 pub struct Exa<'args, 'w, W: Write + 'w> {
 

src/options/style.rs

@@ -122,7 +122,7 @@ impl Styles {
 /// Also returns if the EXA_COLORS variable should reset the existing file
 /// type mappings or not. The `reset` code needs to be the first one.
 fn parse_color_vars<V: Vars>(vars: &V, colours: &mut Colours) -> (ExtensionMappings, bool) {
-    use log::warn;
+    use log::*;
 
     use crate::options::vars;
     use crate::style::LSColors;

src/output/details.rs

@@ -194,7 +194,7 @@ impl<'a> Render<'a> {
     /// parallelisable, and uses a pool of threads.
     fn add_files_to_table<'dir, 'ig>(&self, pool: &mut Pool, table: &mut Option<Table<'a>>, rows: &mut Vec<Row>, src: &[File<'dir>], git: Option<&'ig GitCache>, depth: TreeDepth) {
         use std::sync::{Arc, Mutex};
-        use log::error;
+        use log::*;
         use crate::fs::feature::xattr;
 
         let mut file_eggs = (0..src.len()).map(|_| MaybeUninit::uninit()).collect::<Vec<_>>();

src/output/table.rs

@@ -7,7 +7,7 @@ use std::sync::{Mutex, MutexGuard};
 use datetime::TimeZone;
 use zoneinfo_compiled::{CompiledData, Result as TZResult};
 
-use log::debug;
+use log::*;
 
 use users::UsersCache;