From d841f3daea3cd6e4fbe09d83a7b2376862721174 Mon Sep 17 00:00:00 2001
From: Benjamin Nguyen <benjamin.van.nguyen@gmail.com>
Date: Fri, 16 Jun 2023 17:25:49 -0700
Subject: [PATCH 1/8] fix hacks

---
 src/context/mod.rs | 124 +++++++++++++++++++++++----------------------
 src/main.rs        |  15 +++---
 src/utils.rs       |  15 ------
 3 files changed, 72 insertions(+), 82 deletions(-)

diff --git a/src/context/mod.rs b/src/context/mod.rs
index 72765879..f524ad7f 100644
--- a/src/context/mod.rs
+++ b/src/context/mod.rs
@@ -244,6 +244,7 @@ pub struct Context {
 trait AsVecOfStr {
     fn as_vec_of_str(&self) -> Vec<&str>;
 }
+
 impl AsVecOfStr for ArgMatches {
     fn as_vec_of_str(&self) -> Vec<&str> {
         self.ids().map(Id::as_str).collect()
@@ -255,70 +256,70 @@ type Predicate = Result<Box<dyn Fn(&DirEntry) -> bool + Send + Sync + 'static>,
 impl Context {
     /// Initializes [Context], optionally reading in the configuration file to override defaults.
     /// Arguments provided will take precedence over config.
-    pub fn init() -> Result<Self, Error> {
+    pub fn try_init() -> Result<Self, Error> {
+        // User-provided arguments from command-line.
         let user_args = Self::command().args_override_self(true).get_matches();
 
-        let no_config = user_args
-            .get_one::<bool>("no_config")
-            .copied()
-            .unwrap_or(false);
-
-        if no_config {
+        if user_args.get_one::<bool>("no_config").is_some_and(|b| *b) {
             return Self::from_arg_matches(&user_args).map_err(Error::ArgParse);
         }
 
-        if let Some(ref config) = config::read_config_to_string::<&str>(None) {
-            let raw_config_args = config::parse(config);
-            let config_args = Self::command().get_matches_from(raw_config_args);
+        let Some(config) = config::read_config_to_string::<&str>(None) else {
+            return Self::from_arg_matches(&user_args).map_err(Error::ArgParse)
+        };
 
-            // If the user did not provide any arguments just read from config.
-            if !user_args.args_present() {
-                return Self::from_arg_matches(&config_args).map_err(Error::Config);
-            }
+        let raw_config_args = config::parse(&config);
 
-            // If the user did provide arguments we need to reconcile between config and
-            // user arguments.
-            let mut args = vec![OsString::from("--")];
+        // Config-provided command-line arguments.
+        let config_args = Self::command().get_matches_from(raw_config_args);
 
-            let mut ids = user_args.as_vec_of_str();
+        // If the user did not provide any arguments just read from config.
+        if !user_args.args_present() {
+            return Self::from_arg_matches(&config_args).map_err(Error::Config);
+        }
 
-            ids.extend(config_args.as_vec_of_str());
+        // Will server as the final list of arguments after user args and
+        // config args have been reconciled.
+        let mut args = vec![OsString::from("--")];
 
-            ids = crate::utils::uniq(ids);
+        let ids = Self::command()
+            .get_arguments()
+            .map(|arg| arg.get_id().clone())
+            .collect::<Vec<_>>();
 
-            // HACK:
-            // Going to need to figure out how to handle this better.
-            for id in ids
-                .into_iter()
-                .filter(|&id| id != "Context" && id != "group" && id != "searching")
-            {
-                if id == "dir" {
-                    if let Ok(Some(raw)) = user_args.try_get_raw(id) {
-                        let raw_args = raw.map(OsStr::to_owned).collect::<Vec<OsString>>();
+        for id in ids {
+            let id_str = id.as_str();
 
-                        args.extend(raw_args);
-                        continue;
-                    }
+            if id_str == "dir" {
+                if let Ok(Some(dir)) = user_args.try_get_one::<PathBuf>(id_str) {
+                    args.push(dir.as_os_str().to_owned());
+                    continue;
                 }
+            }
 
-                if let Some(user_arg) = user_args.value_source(id) {
-                    match user_arg {
-                        // prioritize the user arg if user provided a command line argument
-                        ValueSource::CommandLine => Self::pick_args_from(id, &user_args, &mut args),
-
-                        // otherwise prioritize argument from the config
-                        _ => Self::pick_args_from(id, &config_args, &mut args),
-                    }
-                } else {
-                    Self::pick_args_from(id, &config_args, &mut args);
+            let Some(source) = user_args.value_source(id_str) else {
+                if let Some(params) = Self::extract_args_from(id_str, &config_args) {
+                    args.extend(params);
                 }
-            }
+                continue;
+            };
 
-            let clargs = Self::command().get_matches_from(args);
-            return Self::from_arg_matches(&clargs).map_err(Error::Config);
+            let higher_precedent = match source {
+                // User provided argument takes precedent over argument from config
+                ValueSource::CommandLine => &user_args,
+
+                // otherwise prioritize argument from the config
+                _ => &config_args,
+            };
+
+            if let Some(params) = Self::extract_args_from(id_str, higher_precedent) {
+                args.extend(params);
+            }
         }
 
-        Self::from_arg_matches(&user_args).map_err(Error::ArgParse)
+        let clargs = Self::command().get_matches_from(args);
+
+        Self::from_arg_matches(&clargs).map_err(Error::Config)
     }
 
     /// Determines whether or not it's appropriate to display color in output based on
@@ -369,20 +370,23 @@ impl Context {
     }
 
     /// Used to pick either from config or user args when constructing [Context].
-    fn pick_args_from(id: &str, matches: &ArgMatches, args: &mut Vec<OsString>) {
-        if let Ok(Some(raw)) = matches.try_get_raw(id) {
-            let kebap = id.replace('_', "-");
-
-            let raw_args = raw
-                .map(OsStr::to_owned)
-                .map(|s| vec![OsString::from(format!("--{kebap}")), s])
-                .filter(|pair| pair[1] != "false")
-                .flatten()
-                .filter(|s| s != "true")
-                .collect::<Vec<_>>();
-
-            args.extend(raw_args);
-        }
+    #[inline]
+    fn extract_args_from(id: &str, matches: &ArgMatches) -> Option<Vec<OsString>> {
+        let Ok(Some(raw)) = matches.try_get_raw(id) else {
+            return None
+        };
+
+        let kebap = format!("--{}", id.replace('_', "-"));
+
+        let raw_args = raw
+            .map(OsStr::to_owned)
+            .map(|s| [OsString::from(&kebap), s])
+            .filter(|[_key, val]| val != "false")
+            .flatten()
+            .filter(|s| s != "true")
+            .collect::<Vec<_>>();
+
+        Some(raw_args)
     }
 
     /// Predicate used for filtering via regular expressions and file-type. When matching regular
diff --git a/src/main.rs b/src/main.rs
index 8daf7b27..1fb61e53 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -72,7 +72,7 @@ fn main() -> ExitCode {
 }
 
 fn run() -> Result<(), Box<dyn Error>> {
-    let ctx = Context::init()?;
+    let ctx = Context::try_init()?;
 
     if let Some(shell) = ctx.completions {
         clap_complete::generate(shell, &mut Context::command(), "erd", &mut stdout());
@@ -83,12 +83,13 @@ fn run() -> Result<(), Box<dyn Error>> {
 
     let indicator = (ctx.stdout_is_tty && !ctx.no_progress).then(progress::Indicator::measure);
 
-    let (tree, ctx) = Tree::try_init_and_update_context(ctx, indicator.as_ref()).map_err(|err| {
-        if let Some(progress) = &indicator {
-            progress.mailbox().send(Message::RenderReady).unwrap()
-        }
-        err
-    })?;
+    let (tree, ctx) =
+        Tree::try_init_and_update_context(ctx, indicator.as_ref()).map_err(|err| {
+            if let Some(ref progress) = indicator {
+                progress.mailbox().send(Message::RenderReady).unwrap();
+            }
+            err
+        })?;
 
     let output = match ctx.layout {
         layout::Type::Flat => {
diff --git a/src/utils.rs b/src/utils.rs
index 13786a7e..f84e8038 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -1,5 +1,3 @@
-use std::{cmp::Eq, collections::HashSet, hash::Hash};
-
 #[macro_export]
 /// Ruby-like way to crate a hashmap.
 macro_rules! hash {
@@ -21,19 +19,6 @@ macro_rules! hash {
     };
 }
 
-/// Ensure every item in a `Vec` is unique.
-#[inline]
-pub fn uniq<T>(items: Vec<T>) -> Vec<T>
-where
-    T: Eq + Hash,
-{
-    items
-        .into_iter()
-        .collect::<HashSet<_>>()
-        .into_iter()
-        .collect()
-}
-
 /// How many integral digits are there?
 #[inline]
 pub const fn num_integral(value: u64) -> usize {

From b9d09c6831d270ce8a099ae6339a66af51f34c0f Mon Sep 17 00:00:00 2001
From: Benjamin Nguyen <benjamin.van.nguyen@gmail.com>
Date: Sun, 25 Jun 2023 17:48:13 -0700
Subject: [PATCH 2/8] support multi-config with toml config file

---
 Cargo.lock                              | 303 ++++++++++++++++++++++++
 Cargo.toml                              |   1 +
 src/context/config/mod.rs               |  22 ++
 src/context/{config.rs => config/rc.rs} |  58 ++---
 src/context/config/toml/error.rs        |  19 ++
 src/context/config/toml/mod.rs          | 222 +++++++++++++++++
 src/context/config/toml/test.rs         |  91 +++++++
 src/context/error.rs                    |  15 +-
 src/context/mod.rs                      |  47 ++--
 src/context/test.rs                     |  37 ---
 tests/data/.erdtreerc                   |   3 -
 11 files changed, 712 insertions(+), 106 deletions(-)
 create mode 100644 src/context/config/mod.rs
 rename src/context/{config.rs => config/rc.rs} (64%)
 create mode 100644 src/context/config/toml/error.rs
 create mode 100644 src/context/config/toml/mod.rs
 create mode 100644 src/context/config/toml/test.rs
 delete mode 100644 src/context/test.rs
 delete mode 100644 tests/data/.erdtreerc

diff --git a/Cargo.lock b/Cargo.lock
index efe10645..7d9fa5f9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,6 +2,17 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "ahash"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fcb51a0695d8f838b1ee009b3fbf66bda078cd64590202a864a8f3e8c4315c47"
+dependencies = [
+ "getrandom",
+ "once_cell",
+ "version_check",
+]
+
 [[package]]
 name = "aho-corasick"
 version = "0.7.20"
@@ -35,18 +46,44 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "23b62fc65de8e4e7f52534fb52b0f3ed04746ae267519eef2a83941e8085068b"
 
+[[package]]
+name = "async-trait"
+version = "0.1.68"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9ccdd8f2a161be9bd5c023df56f1b2a0bd1d83872ae53b71a84a12c9bf6e842"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.10",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
+[[package]]
+name = "base64"
+version = "0.13.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9e1b586273c5702936fe7b7d6896644d8be71e6314cfe09d3167c95f712589e8"
+
 [[package]]
 name = "bitflags"
 version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
+[[package]]
+name = "block-buffer"
+version = "0.10.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3078c7629b62d3f0439517fa394996acacc5cbc91c5a20d8c658e77abd503a71"
+dependencies = [
+ "generic-array",
+]
+
 [[package]]
 name = "bstr"
 version = "1.3.0"
@@ -146,12 +183,40 @@ dependencies = [
  "unicode-width",
 ]
 
+[[package]]
+name = "config"
+version = "0.13.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d379af7f68bfc21714c6c7dea883544201741d2ce8274bb12fa54f89507f52a7"
+dependencies = [
+ "async-trait",
+ "json5",
+ "lazy_static",
+ "nom",
+ "pathdiff",
+ "ron",
+ "rust-ini",
+ "serde",
+ "serde_json",
+ "toml",
+ "yaml-rust",
+]
+
 [[package]]
 name = "core-foundation-sys"
 version = "0.8.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e496a50fda8aacccc86d7529e2c1e0892dbd0f898a6b5645b5561b89c3210efa"
 
+[[package]]
+name = "cpufeatures"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "03e69e28e9f7f77debdedbaafa2866e1de9ba56df55a8bd7cfc724c25a09987c"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "crossterm"
 version = "0.26.1"
@@ -177,6 +242,16 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "crypto-common"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1bfb12502f3fc46cca1bb51ac28df9d618d813cdc3d2f25b9fe775a34af26bb3"
+dependencies = [
+ "generic-array",
+ "typenum",
+]
+
 [[package]]
 name = "cxx"
 version = "1.0.94"
@@ -221,6 +296,16 @@ dependencies = [
  "syn 2.0.10",
 ]
 
+[[package]]
+name = "digest"
+version = "0.10.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
+dependencies = [
+ "block-buffer",
+ "crypto-common",
+]
+
 [[package]]
 name = "dirs"
 version = "5.0.0"
@@ -241,6 +326,12 @@ dependencies = [
  "windows-sys 0.45.0",
 ]
 
+[[package]]
+name = "dlv-list"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0688c2a7f92e427f44895cd63841bff7b29f8d7a1648b9e7e07a4a365b2e1257"
+
 [[package]]
 name = "erdtree"
 version = "3.0.2"
@@ -249,6 +340,7 @@ dependencies = [
  "chrono",
  "clap",
  "clap_complete",
+ "config",
  "crossterm",
  "dirs",
  "errno 0.3.1",
@@ -322,6 +414,16 @@ version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
+[[package]]
+name = "generic-array"
+version = "0.14.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "85649ca51fd72272d7821adaf274ad91c288277713d9c18820d8499a7ff69e9a"
+dependencies = [
+ "typenum",
+ "version_check",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.2.9"
@@ -346,6 +448,15 @@ dependencies = [
  "regex",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.12.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a9ee70c43aaf417c914396645a0fa852624801b24ebb7ae78fe8272889ac888"
+dependencies = [
+ "ahash",
+]
+
 [[package]]
 name = "heck"
 version = "0.4.1"
@@ -443,6 +554,12 @@ dependencies = [
  "windows-sys 0.45.0",
 ]
 
+[[package]]
+name = "itoa"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "453ad9f582a441959e5f0d088b02ce04cfe8d51a8eaf077f12ac6d3e94164ca6"
+
 [[package]]
 name = "js-sys"
 version = "0.3.61"
@@ -452,6 +569,17 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "json5"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "96b0db21af676c1ce64250b5f40f3ce2cf27e4e47cb91ed91eb6fe9350b430c1"
+dependencies = [
+ "pest",
+ "pest_derive",
+ "serde",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -473,6 +601,12 @@ dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "linked-hash-map"
+version = "0.5.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0717cef1bc8b636c6e1c1bbdefc09e6322da8a9321966e8928ef80d20f7f770f"
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.1.4"
@@ -520,6 +654,12 @@ version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
 
+[[package]]
+name = "minimal-lexical"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
 [[package]]
 name = "mio"
 version = "0.8.6"
@@ -532,6 +672,16 @@ dependencies = [
  "windows-sys 0.45.0",
 ]
 
+[[package]]
+name = "nom"
+version = "7.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
+dependencies = [
+ "memchr",
+ "minimal-lexical",
+]
+
 [[package]]
 name = "nu-ansi-term"
 version = "0.46.0"
@@ -567,6 +717,16 @@ version = "1.17.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b7e5500299e16ebb147ae15a00a942af264cf3688f47923b8fc2cd5858f23ad3"
 
+[[package]]
+name = "ordered-multimap"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ccd746e37177e1711c20dd619a1620f34f5c8b569c53590a72dedd5344d8924a"
+dependencies = [
+ "dlv-list",
+ "hashbrown",
+]
+
 [[package]]
 name = "os_str_bytes"
 version = "6.4.1"
@@ -602,6 +762,56 @@ dependencies = [
  "windows-sys 0.45.0",
 ]
 
+[[package]]
+name = "pathdiff"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8835116a5c179084a830efb3adc117ab007512b535bc1a21c991d3b32a6b44dd"
+
+[[package]]
+name = "pest"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "16833386b02953ca926d19f64af613b9bf742c48dcd5e09b32fbfc9740bf84e2"
+dependencies = [
+ "thiserror",
+ "ucd-trie",
+]
+
+[[package]]
+name = "pest_derive"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7763190f9406839f99e5197afee8c9e759969f7dbfa40ad3b8dbee8757b745b5"
+dependencies = [
+ "pest",
+ "pest_generator",
+]
+
+[[package]]
+name = "pest_generator"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "249061b22e99973da1f5f5f1410284419e283bb60b79255bf5f42a94b66a2e00"
+dependencies = [
+ "pest",
+ "pest_meta",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.10",
+]
+
+[[package]]
+name = "pest_meta"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "457c310cfc9cf3f22bc58901cc7f0d3410ac5d6298e432a4f9a6138565cb6df6"
+dependencies = [
+ "once_cell",
+ "pest",
+ "sha2",
+]
+
 [[package]]
 name = "proc-macro-error"
 version = "1.0.4"
@@ -681,6 +891,27 @@ version = "0.6.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f162c6dd7b008981e4d40210aca20b4bd0f9b60ca9271061b07f78537722f2e1"
 
+[[package]]
+name = "ron"
+version = "0.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "88073939a61e5b7680558e6be56b419e208420c2adb92be54921fa6b72283f1a"
+dependencies = [
+ "base64",
+ "bitflags",
+ "serde",
+]
+
+[[package]]
+name = "rust-ini"
+version = "0.18.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f6d5f2436026b4f6e79dc829837d467cc7e9a55ee40e750d716713540715a2df"
+dependencies = [
+ "cfg-if",
+ "ordered-multimap",
+]
+
 [[package]]
 name = "rustix"
 version = "0.36.9"
@@ -709,6 +940,12 @@ dependencies = [
  "windows-sys 0.45.0",
 ]
 
+[[package]]
+name = "ryu"
+version = "1.0.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f91339c0467de62360649f8d3e185ca8de4224ff281f66000de5eb2a77a79041"
+
 [[package]]
 name = "same-file"
 version = "1.0.6"
@@ -735,6 +972,42 @@ name = "serde"
 version = "1.0.156"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "314b5b092c0ade17c00142951e50ced110ec27cea304b1037c6969246c2469a4"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.156"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d7e29c4601e36bcec74a223228dce795f4cd3616341a4af93520ca1a837c087d"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
+[[package]]
+name = "serde_json"
+version = "1.0.97"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bdf3bf93142acad5821c99197022e170842cdbc1c30482b98750c688c640842a"
+dependencies = [
+ "itoa",
+ "ryu",
+ "serde",
+]
+
+[[package]]
+name = "sha2"
+version = "0.10.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "479fb9d862239e610720565ca91403019f2f00410f1864c5aa7479b950a76ed8"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest",
+]
 
 [[package]]
 name = "signal-hook"
@@ -872,6 +1145,27 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "toml"
+version = "0.5.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f4f7f0dd8d50a853a531c426359045b1998f04219d88799810762cd4ad314234"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "typenum"
+version = "1.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "497961ef93d974e23eb6f433eb5fe1b7930b659f06d12dec6fc44a8f554c0bba"
+
+[[package]]
+name = "ucd-trie"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9e79c4d996edb816c91e4308506774452e55e95c3c9de07b6729e17e15a5ef81"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.8"
@@ -1179,3 +1473,12 @@ name = "windows_x86_64_msvc"
 version = "0.48.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1a515f5799fe4961cb532f983ce2b23082366b898e52ffbce459c86f67c8378a"
+
+[[package]]
+name = "yaml-rust"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
+dependencies = [
+ "linked-hash-map",
+]
diff --git a/Cargo.toml b/Cargo.toml
index c6eb1e4d..3060e9a3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -28,6 +28,7 @@ ansi_term = "0.12.1"
 chrono = "0.4.24"
 clap = { version = "4.1.1", features = ["derive"] }
 clap_complete = "4.1.1"
+config = { version = "0.13.3", features = ["toml"] }
 crossterm = "0.26.1"
 dirs = "5.0"
 errno = "0.3.1"
diff --git a/src/context/config/mod.rs b/src/context/config/mod.rs
new file mode 100644
index 00000000..c28c3a7a
--- /dev/null
+++ b/src/context/config/mod.rs
@@ -0,0 +1,22 @@
+const ERDTREE_CONFIG_TOML: &str = ".erdtree.toml";
+const ERDTREE_TOML_PATH: &str = "ERDTREE_TOML_PATH";
+
+const ERDTREE_CONFIG_NAME: &str = ".erdtreerc";
+const ERDTREE_CONFIG_PATH: &str = "ERDTREE_CONFIG_PATH";
+
+const ERDTREE_DIR: &str = "erdtree";
+
+#[cfg(unix)]
+const CONFIG_DIR: &str = ".config";
+
+#[cfg(unix)]
+const HOME: &str = "HOME";
+
+#[cfg(unix)]
+const XDG_CONFIG_HOME: &str = "XDG_CONFIG_HOME";
+
+/// Concerned with loading `.erdtreerc`.
+pub mod rc;
+
+/// Concerned with loading `.erdtree.toml`.
+pub mod toml;
diff --git a/src/context/config.rs b/src/context/config/rc.rs
similarity index 64%
rename from src/context/config.rs
rename to src/context/config/rc.rs
index 377d48bf..7e230c95 100644
--- a/src/context/config.rs
+++ b/src/context/config/rc.rs
@@ -1,20 +1,4 @@
-use std::{
-    env, fs,
-    path::{Path, PathBuf},
-};
-
-const ERDTREE_CONFIG_NAME: &str = ".erdtreerc";
-const ERDTREE_CONFIG_PATH: &str = "ERDTREE_CONFIG_PATH";
-const ERDTREE_DIR: &str = "erdtree";
-
-#[cfg(unix)]
-const CONFIG_DIR: &str = ".config";
-
-#[cfg(unix)]
-const HOME: &str = "HOME";
-
-#[cfg(unix)]
-const XDG_CONFIG_HOME: &str = "XDG_CONFIG_HOME";
+use std::{env, fs, path::PathBuf};
 
 /// Reads the config file into a `String` if there is one. When `None` is provided then the config
 /// is looked for in the following locations in order:
@@ -25,25 +9,19 @@ const XDG_CONFIG_HOME: &str = "XDG_CONFIG_HOME";
 /// - `$HOME/.config/erdtree/.erdtreerc`
 /// - `$HOME/.erdtreerc`
 #[cfg(unix)]
-pub fn read_config_to_string<T: AsRef<Path>>(path: Option<T>) -> Option<String> {
-    path.map(fs::read_to_string)
-        .and_then(Result::ok)
-        .or_else(config_from_config_path)
+pub fn read_config_to_string() -> Option<String> {
+    config_from_config_path()
         .or_else(config_from_xdg_path)
         .or_else(config_from_home)
         .map(|e| prepend_arg_prefix(&e))
 }
-
-/// Reads the config file into a `String` if there is one. When `None` is provided then the config
 /// is looked for in the following locations in order (Windows specific):
 ///
 /// - `$ERDTREE_CONFIG_PATH`
 /// - `%APPDATA%/erdtree/.erdtreerc`
 #[cfg(windows)]
-pub fn read_config_to_string<T: AsRef<Path>>(path: Option<T>) -> Option<String> {
-    path.map(fs::read_to_string)
-        .and_then(Result::ok)
-        .or_else(config_from_config_path)
+pub fn read_config_to_string() -> Option<String> {
+    config_from_config_path()
         .or_else(config_from_appdata)
         .map(|e| prepend_arg_prefix(&e))
 }
@@ -61,13 +39,13 @@ pub fn parse<'a>(config: &'a str) -> Vec<&'a str> {
                 .next()
                 .map_or(true, |ch| ch != '#')
         })
-        .flat_map(str::split_ascii_whitespace)
+        .flat_map(str::split_whitespace)
         .collect::<Vec<&'a str>>()
 }
 
 /// Try to read in config from `ERDTREE_CONFIG_PATH`.
 fn config_from_config_path() -> Option<String> {
-    env::var_os(ERDTREE_CONFIG_PATH)
+    env::var_os(super::ERDTREE_CONFIG_PATH)
         .map(PathBuf::from)
         .map(fs::read_to_string)
         .and_then(Result::ok)
@@ -78,15 +56,15 @@ fn config_from_config_path() -> Option<String> {
 /// - `$HOME/.erdtreerc`
 #[cfg(not(windows))]
 fn config_from_home() -> Option<String> {
-    let home = env::var_os(HOME).map(PathBuf::from)?;
+    let home = env::var_os(super::HOME).map(PathBuf::from)?;
 
     let config_path = home
-        .join(CONFIG_DIR)
-        .join(ERDTREE_DIR)
-        .join(ERDTREE_CONFIG_NAME);
+        .join(super::CONFIG_DIR)
+        .join(super::ERDTREE_DIR)
+        .join(super::ERDTREE_CONFIG_NAME);
 
     fs::read_to_string(config_path).ok().or_else(|| {
-        let config_path = home.join(ERDTREE_CONFIG_NAME);
+        let config_path = home.join(super::ERDTREE_CONFIG_NAME);
         fs::read_to_string(config_path).ok()
     })
 }
@@ -97,7 +75,9 @@ fn config_from_home() -> Option<String> {
 fn config_from_appdata() -> Option<String> {
     let app_data = dirs::config_dir()?;
 
-    let config_path = app_data.join(ERDTREE_DIR).join(ERDTREE_CONFIG_NAME);
+    let config_path = app_data
+        .join(super::ERDTREE_DIR)
+        .join(super::ERDTREE_CONFIG_NAME);
 
     fs::read_to_string(config_path).ok()
 }
@@ -107,12 +87,14 @@ fn config_from_appdata() -> Option<String> {
 /// - `$XDG_CONFIG_HOME/.erdtreerc`
 #[cfg(unix)]
 fn config_from_xdg_path() -> Option<String> {
-    let xdg_config = env::var_os(XDG_CONFIG_HOME).map(PathBuf::from)?;
+    let xdg_config = env::var_os(super::XDG_CONFIG_HOME).map(PathBuf::from)?;
 
-    let config_path = xdg_config.join(ERDTREE_DIR).join(ERDTREE_CONFIG_NAME);
+    let config_path = xdg_config
+        .join(super::ERDTREE_DIR)
+        .join(super::ERDTREE_CONFIG_NAME);
 
     fs::read_to_string(config_path).ok().or_else(|| {
-        let config_path = xdg_config.join(ERDTREE_CONFIG_NAME);
+        let config_path = xdg_config.join(super::ERDTREE_CONFIG_NAME);
         fs::read_to_string(config_path).ok()
     })
 }
diff --git a/src/context/config/toml/error.rs b/src/context/config/toml/error.rs
new file mode 100644
index 00000000..c6a4be39
--- /dev/null
+++ b/src/context/config/toml/error.rs
@@ -0,0 +1,19 @@
+use config::ConfigError;
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("Failed to load .erdtree.toml")]
+    LoadConfig,
+
+    #[error("The configuration file is improperly formatted")]
+    InvalidFormat(#[from] ConfigError),
+
+    #[error("Alternate configuration '{0}' was not found in '.erdtree.toml'")]
+    MissingAltConfig(String),
+
+    #[error("'#{0}' is required to be a pointer-sized unsigned integer type")]
+    InvalidInteger(String),
+
+    #[error("'#{0}' has a type that is invalid")]
+    InvalidArgument(String),
+}
diff --git a/src/context/config/toml/mod.rs b/src/context/config/toml/mod.rs
new file mode 100644
index 00000000..4ac63865
--- /dev/null
+++ b/src/context/config/toml/mod.rs
@@ -0,0 +1,222 @@
+use config::{Config, File, Value, ValueKind};
+use error::Error;
+use std::{env, ffi::OsString};
+
+/// Errors associated with loading and parsing the toml config file.
+pub mod error;
+
+/// Testing related to `.erdtree.toml`.
+pub mod test;
+
+/// Represents an instruction on how to handle a single key-value pair, which makes up a single
+/// command-line argument, when constructing the arguments vector.
+enum ArgInstructions {
+    /// Used for bool arguments such as `--icons`. When `icons = true` is set in `.erdtree.toml`,
+    /// we only want `--icons` to be pushed into the ultimate arguments vector.
+    PushKeyOnly,
+
+    /// Used for arguments such as `--threads 10`.
+    PushKeyValue { parsed_value: OsString },
+
+    /// If a bool field is set to false in `.erdtree.toml` (e.g. `icons = false`) then we want to
+    /// completely omit the key-value pair from the arguments that we ultimately use.
+    Pass,
+}
+
+/// Takes in a `Config` that is generated from [`load_toml`] returning a `Vec<OsString>` which
+/// represents command-line arguments from `.erdtree.toml`. If a `nested_table` is provided then
+/// the top-level table in `.erdtree.toml` is ignored and the configurations specified in the
+/// `nested_table` will be used instead.
+pub fn parse(config: Config, nested_table: Option<&str>) -> Result<Vec<OsString>, Error> {
+    let mut args_map = config.cache.into_table()?;
+
+    if let Some(table) = nested_table {
+        let new_conf = args_map
+            .get(table)
+            .and_then(|conf| conf.clone().into_table().ok())
+            .ok_or_else(|| Error::MissingAltConfig(table.to_owned()))?;
+
+        args_map = new_conf;
+    } else {
+        args_map.retain(|_k, v| !matches!(v.kind, ValueKind::Table(_)));
+    }
+
+    let mut parsed_args = vec![OsString::from("--")];
+
+    let process_key = |s| OsString::from(format!("--{s}").replace('_', "-"));
+
+    for (k, v) in &args_map {
+        match parse_argument(k, v)? {
+            ArgInstructions::PushKeyValue { parsed_value } => {
+                let fmt_key = process_key(k);
+                parsed_args.push(fmt_key);
+                parsed_args.push(parsed_value);
+            }
+
+            ArgInstructions::PushKeyOnly => {
+                let fmt_key = process_key(k);
+                parsed_args.push(fmt_key);
+            }
+
+            ArgInstructions::Pass => continue,
+        }
+    }
+
+    Ok(parsed_args)
+}
+
+/// Reads in `.erdtree.toml` file.
+pub fn load() -> Result<Config, Error> {
+    #[cfg(windows)]
+    return windows::load_toml().ok_or(Error::LoadConfig);
+
+    #[cfg(unix)]
+    unix::load_toml().ok_or(Error::LoadConfig)
+}
+
+/// Attempts to load in `.erdtree.toml` from `$ERDTREE_TOML_PATH`. Will return `None` for whatever
+/// reason.
+fn toml_from_env() -> Option<Config> {
+    let config = env::var_os(super::ERDTREE_TOML_PATH)
+        .map(OsString::into_string)
+        .and_then(Result::ok)?;
+
+    let file = config.strip_suffix(".toml").map(File::with_name)?;
+
+    Config::builder().add_source(file).build().ok()
+}
+
+/// Simple utility used to extract the underlying value from the [`Value`] enum that we get when
+/// loading in the values from `.erdtree.toml`, returning instructions on how the argument should
+/// be processed into the ultimate arguments vector.
+fn parse_argument(keyword: &str, arg: &Value) -> Result<ArgInstructions, Error> {
+    macro_rules! try_parse_num {
+        ($n:expr) => {
+            usize::try_from($n)
+                .map_err(|_e| Error::InvalidInteger(keyword.to_owned()))
+                .map(|num| {
+                    let parsed = OsString::from(format!("{num}"));
+                    ArgInstructions::PushKeyValue {
+                        parsed_value: parsed,
+                    }
+                })
+        };
+    }
+
+    match &arg.kind {
+        ValueKind::Boolean(val) => {
+            if *val {
+                Ok(ArgInstructions::PushKeyOnly)
+            } else {
+                Ok(ArgInstructions::Pass)
+            }
+        }
+        ValueKind::String(val) => Ok(ArgInstructions::PushKeyValue {
+            parsed_value: OsString::from(val),
+        }),
+        ValueKind::I64(val) => try_parse_num!(*val),
+        ValueKind::I128(val) => try_parse_num!(*val),
+        ValueKind::U64(val) => try_parse_num!(*val),
+        ValueKind::U128(val) => try_parse_num!(*val),
+        _ => Err(Error::InvalidArgument(keyword.to_owned())),
+    }
+}
+
+#[cfg(unix)]
+mod unix {
+    use super::super::{CONFIG_DIR, ERDTREE_CONFIG_TOML, ERDTREE_DIR, HOME, XDG_CONFIG_HOME};
+    use config::{Config, File};
+    use std::{env, path::PathBuf};
+
+    /// Looks for `.erdtree.toml` in the following locations in order:
+    ///
+    /// - `$ERDTREE_TOML_PATH`
+    /// - `$XDG_CONFIG_HOME/erdtree/.erdtree.toml`
+    /// - `$XDG_CONFIG_HOME/.erdtree.toml`
+    /// - `$HOME/.config/erdtree/.erdtree.toml`
+    /// - `$HOME/.erdtree.toml`
+    pub(super) fn load_toml() -> Option<Config> {
+        super::toml_from_env()
+            .or_else(toml_from_xdg_path)
+            .or_else(toml_from_home)
+    }
+
+    /// Looks for `.erdtree.toml` in the following locations in order:
+    ///
+    /// - `$XDG_CONFIG_HOME/erdtree/.erdtree.toml`
+    /// - `$XDG_CONFIG_HOME/.erdtree.toml`
+    fn toml_from_xdg_path() -> Option<Config> {
+        let config = env::var_os(XDG_CONFIG_HOME).map(PathBuf::from)?;
+
+        let mut file = config
+            .join(ERDTREE_DIR)
+            .join(ERDTREE_CONFIG_TOML)
+            .to_str()
+            .and_then(|s| s.strip_suffix(".toml"))
+            .map(File::with_name);
+
+        if file.is_none() {
+            file = config
+                .join(ERDTREE_CONFIG_TOML)
+                .to_str()
+                .and_then(|s| s.strip_suffix(".toml"))
+                .map(File::with_name);
+        }
+
+        Config::builder().add_source(file?).build().ok()
+    }
+
+    /// Looks for `.erdtree.toml` in the following locations in order:
+    ///
+    /// - `$HOME/.config/erdtree/.erdtree.toml`
+    /// - `$HOME/.erdtree.toml`
+    fn toml_from_home() -> Option<Config> {
+        let home = env::var_os(HOME).map(PathBuf::from)?;
+
+        let mut file = home
+            .join(CONFIG_DIR)
+            .join(ERDTREE_DIR)
+            .join(ERDTREE_CONFIG_TOML)
+            .to_str()
+            .and_then(|s| s.strip_suffix(".toml"))
+            .map(File::with_name);
+
+        if file.is_none() {
+            file = home
+                .join(ERDTREE_CONFIG_TOML)
+                .to_str()
+                .and_then(|s| s.strip_suffix(".toml"))
+                .map(File::with_name);
+        }
+
+        Config::builder().add_source(file?).build().ok()
+    }
+}
+
+#[cfg(windows)]
+mod windows {
+    use super::super::{ERDTREE_CONFIG_TOML, ERDTREE_DIR};
+    use config::{Config, File};
+    use std::{env, path::PathBuf};
+
+    /// Try to read in config from the following location:
+    /// - `%APPDATA%/erdtree/.erdtreerc`
+    pub(super) fn load_toml() -> Option<Config> {
+        super::toml_from_env().or_else(toml_from_appdata)
+    }
+
+    /// Try to read in config from the following location:
+    /// - `%APPDATA%/erdtree/.erdtreerc`
+    fn toml_from_appdata() -> Option<Config> {
+        let app_data = dirs::config_dir()?;
+
+        let file = app_data
+            .join(ERDTREE_DIR)
+            .join(ERDTREE_CONFIG_TOML)
+            .to_str()
+            .and_then(|s| s.strip_prefix(".toml"))
+            .map(File::with_name)?;
+
+        Config::builder().add_source(file).build().ok()
+    }
+}
diff --git a/src/context/config/toml/test.rs b/src/context/config/toml/test.rs
new file mode 100644
index 00000000..adba50d2
--- /dev/null
+++ b/src/context/config/toml/test.rs
@@ -0,0 +1,91 @@
+#[test]
+fn parse_toml() -> Result<(), Box<dyn std::error::Error>> {
+    use config::{Config, File};
+    use std::{ffi::OsString, io::Write};
+    use tempfile::Builder;
+
+    let mut config_file = Builder::new()
+        .prefix(".erdtree")
+        .suffix(".toml")
+        .tempfile()?;
+
+    let toml_contents = r#"
+        icons = true
+        human = true
+        threads = 10
+
+        [grogoroth]
+        disk_usage = "block"
+        icons = true
+        human = false
+        threads = 10
+    "#;
+
+    config_file.write(toml_contents.as_bytes())?;
+
+    let file = config_file
+        .path()
+        .to_str()
+        .and_then(|s| s.strip_suffix(".toml"))
+        .map(File::with_name)
+        .unwrap();
+
+    let config = Config::builder().add_source(file).build()?;
+
+    // TOP-LEVEL TABLE
+    let mut toml = super::parse(config.clone(), None)?;
+
+    let expected = vec![
+        OsString::from("--"),
+        OsString::from("--icons"),
+        OsString::from("--human"),
+        OsString::from("--threads"),
+        OsString::from("10"),
+    ];
+
+    for (i, outer_item) in expected.iter().enumerate() {
+        for j in 0..toml.len() {
+            let inner_item = &toml[j];
+
+            if outer_item == inner_item {
+                toml.swap(i, j);
+            }
+        }
+    }
+
+    assert_eq!(toml.len(), expected.len());
+
+    for (lhs, rhs) in toml.iter().zip(expected.iter()) {
+        assert_eq!(lhs, rhs);
+    }
+
+    // NAMED-TABLE
+    let mut toml = super::parse(config, Some("grogoroth"))?;
+
+    let expected = vec![
+        OsString::from("--"),
+        OsString::from("--disk-usage"),
+        OsString::from("block"),
+        OsString::from("--icons"),
+        OsString::from("--threads"),
+        OsString::from("10"),
+    ];
+
+    for (i, outer_item) in expected.iter().enumerate() {
+        for j in 0..toml.len() {
+            let inner_item = &toml[j];
+
+            if outer_item == inner_item {
+                toml.swap(i, j);
+            }
+        }
+    }
+
+    assert_eq!(toml.len(), expected.len());
+
+    for (lhs, rhs) in toml.iter().zip(expected.iter()) {
+        assert_eq!(lhs, rhs);
+    }
+
+    Ok(())
+}
diff --git a/src/context/error.rs b/src/context/error.rs
index 518133fd..056d9fb5 100644
--- a/src/context/error.rs
+++ b/src/context/error.rs
@@ -1,14 +1,16 @@
+use super::config::toml::error::Error as TomlError;
 use clap::Error as ClapError;
 use ignore::Error as IgnoreError;
 use regex::Error as RegexError;
+use std::convert::From;
 
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
     #[error("{0}")]
-    ArgParse(#[source] ClapError),
+    ArgParse(ClapError),
 
     #[error("A configuration file was found but failed to parse: {0}")]
-    Config(#[source] ClapError),
+    Config(ClapError),
 
     #[error("No glob was provided")]
     EmptyGlob,
@@ -21,4 +23,13 @@ pub enum Error {
 
     #[error("Missing '--pattern' argument")]
     PatternNotProvided,
+
+    #[error("{0}")]
+    ConfigError(TomlError),
+}
+
+impl From<TomlError> for Error {
+    fn from(value: TomlError) -> Self {
+        Self::ConfigError(value)
+    }
 }
diff --git a/src/context/mod.rs b/src/context/mod.rs
index f524ad7f..d15acf1d 100644
--- a/src/context/mod.rs
+++ b/src/context/mod.rs
@@ -1,6 +1,6 @@
 use super::disk_usage::{file_size::DiskUsage, units::PrefixKind};
 use crate::tty;
-use clap::{parser::ValueSource, ArgMatches, CommandFactory, FromArgMatches, Id, Parser};
+use clap::{parser::ValueSource, ArgMatches, CommandFactory, FromArgMatches, Parser};
 use color::Coloring;
 use error::Error;
 use ignore::{
@@ -12,7 +12,9 @@ use std::{
     borrow::Borrow,
     convert::From,
     ffi::{OsStr, OsString},
+    num::NonZeroUsize,
     path::{Path, PathBuf},
+    thread::available_parallelism,
 };
 
 /// Operations to load in defaults from configuration file.
@@ -43,10 +45,6 @@ pub mod sort;
 #[cfg(unix)]
 pub mod time;
 
-/// Unit tests for [Context]
-#[cfg(test)]
-mod test;
-
 /// Defines the CLI.
 #[derive(Parser, Debug)]
 #[command(name = "erdtree")]
@@ -57,6 +55,10 @@ pub struct Context {
     /// Directory to traverse; defaults to current working directory
     dir: Option<PathBuf>,
 
+    /// Use configuration of named table rather than the top-level table in .erdtree.toml
+    #[arg(short = 'c', long)]
+    pub config: Option<String>,
+
     /// Mode of coloring output
     #[arg(short = 'C', long, value_enum, default_value_t)]
     pub color: Coloring,
@@ -241,16 +243,6 @@ pub struct Context {
     pub window_width: Option<usize>,
 }
 
-trait AsVecOfStr {
-    fn as_vec_of_str(&self) -> Vec<&str>;
-}
-
-impl AsVecOfStr for ArgMatches {
-    fn as_vec_of_str(&self) -> Vec<&str> {
-        self.ids().map(Id::as_str).collect()
-    }
-}
-
 type Predicate = Result<Box<dyn Fn(&DirEntry) -> bool + Send + Sync + 'static>, Error>;
 
 impl Context {
@@ -260,26 +252,29 @@ impl Context {
         // User-provided arguments from command-line.
         let user_args = Self::command().args_override_self(true).get_matches();
 
+        // User provides `--no-config`.
         if user_args.get_one::<bool>("no_config").is_some_and(|b| *b) {
             return Self::from_arg_matches(&user_args).map_err(Error::ArgParse);
         }
 
-        let Some(config) = config::read_config_to_string::<&str>(None) else {
-            return Self::from_arg_matches(&user_args).map_err(Error::ArgParse)
-        };
-
-        let raw_config_args = config::parse(&config);
+        // Load in `.erdtreerc` or `.erdtree.toml`.
+        let config_args = if let Some(config) = config::rc::read_config_to_string() {
+            let raw_args = config::rc::parse(&config);
+            Self::command().get_matches_from(raw_args)
+        } else if let Ok(config) = config::toml::load() {
+            let named_table = user_args.get_one::<String>("config");
+            let raw_args = config::toml::parse(config, named_table.map(String::as_str))?;
 
-        // Config-provided command-line arguments.
-        let config_args = Self::command().get_matches_from(raw_config_args);
+            Self::command().get_matches_from(raw_args)
+        } else {
+            return Self::from_arg_matches(&user_args).map_err(Error::ArgParse);
+        };
 
         // If the user did not provide any arguments just read from config.
         if !user_args.args_present() {
             return Self::from_arg_matches(&config_args).map_err(Error::Config);
         }
 
-        // Will server as the final list of arguments after user args and
-        // config args have been reconciled.
         let mut args = vec![OsString::from("--")];
 
         let ids = Self::command()
@@ -568,7 +563,7 @@ impl Context {
     }
 
     /// The default number of threads to use for disk-reads and parallel processing.
-    const fn num_threads() -> usize {
-        3
+    fn num_threads() -> usize {
+        available_parallelism().map(NonZeroUsize::get).unwrap_or(3)
     }
 }
diff --git a/src/context/test.rs b/src/context/test.rs
deleted file mode 100644
index 7aa792ca..00000000
--- a/src/context/test.rs
+++ /dev/null
@@ -1,37 +0,0 @@
-use crate::context::sort;
-use clap::{CommandFactory, FromArgMatches};
-
-use super::{config, Context};
-
-const TEST_CONFIG: &str = "./tests/data/.erdtreerc";
-
-#[test]
-fn config() {
-    let context = context_from_config().expect("Failed to build Context from config path");
-
-    let level = context.level();
-
-    assert_eq!(level, 1, "Failed to properly read 'level' from config");
-
-    let sort = context.sort;
-
-    assert_eq!(
-        sort,
-        sort::Type::Size,
-        "Failed to properly read 'sort' from config"
-    );
-
-    let icons = context.icons;
-
-    assert!(icons, "Failed to properly read 'icons' from config");
-}
-
-fn context_from_config() -> Option<Context> {
-    config::read_config_to_string(Some(TEST_CONFIG))
-        .as_ref()
-        .and_then(|config| {
-            let raw_config_args = config::parse(config);
-            let config_args = Context::command().get_matches_from(raw_config_args);
-            Context::from_arg_matches(&config_args).ok()
-        })
-}
diff --git a/tests/data/.erdtreerc b/tests/data/.erdtreerc
deleted file mode 100644
index dc8d7f41..00000000
--- a/tests/data/.erdtreerc
+++ /dev/null
@@ -1,3 +0,0 @@
---level 1
---sort size
---icons

From 6669ea92e2b44163c55e1cada9e1f9e1fdf53181 Mon Sep 17 00:00:00 2001
From: Benjamin Nguyen <benjamin.van.nguyen@gmail.com>
Date: Sun, 25 Jun 2023 18:37:36 -0700
Subject: [PATCH 3/8] visual bug fix

---
 src/context/config/toml/mod.rs |  4 ++--
 src/context/mod.rs             |  1 +
 src/render/grid/cell.rs        | 22 +++++++++++-----------
 3 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/src/context/config/toml/mod.rs b/src/context/config/toml/mod.rs
index 4ac63865..bb6722be 100644
--- a/src/context/config/toml/mod.rs
+++ b/src/context/config/toml/mod.rs
@@ -200,13 +200,13 @@ mod windows {
     use std::{env, path::PathBuf};
 
     /// Try to read in config from the following location:
-    /// - `%APPDATA%/erdtree/.erdtreerc`
+    /// - `%APPDATA%/erdtree/.erdtree.toml`
     pub(super) fn load_toml() -> Option<Config> {
         super::toml_from_env().or_else(toml_from_appdata)
     }
 
     /// Try to read in config from the following location:
-    /// - `%APPDATA%/erdtree/.erdtreerc`
+    /// - `%APPDATA%/erdtree/.erdtree.toml`
     fn toml_from_appdata() -> Option<Config> {
         let app_data = dirs::config_dir()?;
 
diff --git a/src/context/mod.rs b/src/context/mod.rs
index d15acf1d..3b246930 100644
--- a/src/context/mod.rs
+++ b/src/context/mod.rs
@@ -260,6 +260,7 @@ impl Context {
         // Load in `.erdtreerc` or `.erdtree.toml`.
         let config_args = if let Some(config) = config::rc::read_config_to_string() {
             let raw_args = config::rc::parse(&config);
+
             Self::command().get_matches_from(raw_args)
         } else if let Ok(config) = config::toml::load() {
             let named_table = user_args.get_one::<String>("config");
diff --git a/src/render/grid/cell.rs b/src/render/grid/cell.rs
index 7798374f..b0e58493 100644
--- a/src/render/grid/cell.rs
+++ b/src/render/grid/cell.rs
@@ -278,17 +278,17 @@ impl<'a> Cell<'a> {
             return write!(f, "");
         }
 
-        let padding = ctx.max_size_width
-            + 1
-            + match ctx.disk_usage {
-                DiskUsage::Logical | DiskUsage::Physical => match ctx.unit {
-                    PrefixKind::Si if ctx.human => 2,
-                    PrefixKind::Bin if ctx.human => 3,
-                    PrefixKind::Si => 0,
-                    PrefixKind::Bin => 1,
-                },
-                _ => 0,
-            };
+        let mut padding = ctx.max_size_width + 1;
+
+        match ctx.disk_usage {
+            DiskUsage::Logical | DiskUsage::Physical => match ctx.unit {
+                PrefixKind::Si if ctx.human => padding += 2,
+                PrefixKind::Bin if ctx.human => padding += 3,
+                PrefixKind::Si => padding += 0,
+                PrefixKind::Bin => padding += 1,
+            },
+            _ => padding -= 1,
+        }
 
         let formatted_placeholder = format!("{:>padding$}", styles::PLACEHOLDER);
 

From 76c2973c2f544e3d9b826e9a77c218013b42a6b5 Mon Sep 17 00:00:00 2001
From: Benjamin Nguyen <benjamin.van.nguyen@gmail.com>
Date: Sun, 25 Jun 2023 18:38:47 -0700
Subject: [PATCH 4/8] update error message

---
 src/context/config/toml/error.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/context/config/toml/error.rs b/src/context/config/toml/error.rs
index c6a4be39..3d2e782d 100644
--- a/src/context/config/toml/error.rs
+++ b/src/context/config/toml/error.rs
@@ -8,7 +8,7 @@ pub enum Error {
     #[error("The configuration file is improperly formatted")]
     InvalidFormat(#[from] ConfigError),
 
-    #[error("Alternate configuration '{0}' was not found in '.erdtree.toml'")]
+    #[error("Named table '{0}' was not found in '.erdtree.toml'")]
     MissingAltConfig(String),
 
     #[error("'#{0}' is required to be a pointer-sized unsigned integer type")]

From e54f25f1505f4becfbec45dece95d5a35e44ccce Mon Sep 17 00:00:00 2001
From: Benjamin Nguyen <benjamin.van.nguyen@gmail.com>
Date: Sun, 25 Jun 2023 21:56:05 -0700
Subject: [PATCH 5/8] README

---
 Cargo.toml                     |  2 +-
 README.md                      | 95 ++++++++++++++++++++++++++++------
 example/.erdtree.toml          | 26 ++++++++++
 example/.erdtreerc             |  9 ++++
 src/context/config/toml/mod.rs |  8 +--
 5 files changed, 120 insertions(+), 20 deletions(-)
 create mode 100644 example/.erdtree.toml
 create mode 100644 example/.erdtreerc

diff --git a/Cargo.toml b/Cargo.toml
index 3060e9a3..7982fc68 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,7 +12,7 @@ documentation = "https://github.com/solidiquis/erdtree"
 homepage = "https://github.com/solidiquis/erdtree"
 repository = "https://github.com/solidiquis/erdtree"
 keywords = ["tree", "find", "ls", "du", "commandline"]
-exclude = ["assets/*", "scripts/*"]
+exclude = ["assets/*", "scripts/*", "example/*"]
 readme = "README.md"
 license = "MIT"
 rust-version = "1.70.0"
diff --git a/README.md b/README.md
index a37e6fba..219aae3c 100644
--- a/README.md
+++ b/README.md
@@ -316,6 +316,82 @@ Other means of installation to come.
 
 If `erdtree`'s out-of-the-box defaults don't meet your specific requirements, you can set your own defaults using a configuration file.
 
+The configuration file currently comes in two flavors: `.erdtreerc` (to be deprecated) and `.erdtree.toml`. If you have both,
+`.erdtreerc` will take precedent and `.erdtree.toml` will be disregarded, but please **note that `.erdtreerc` will be deprecated in the near future.** There is
+no reason to have both.
+
+#### .erdtree.toml
+
+`erdtree` will look for `.erdtree.toml in any of the following locations:
+
+On Unix-systems:
+
+```
+$ERDTREE_TOML_PATH
+$XDG_CONFIG_HOME/erdtree/.erdtree.toml
+$XDG_CONFIG_HOME/.erdtree.toml
+$HOME/.config/erdtree/.erdtree.toml
+$HOME/.erdtree.toml
+```
+
+On Windows:
+
+```
+%APPDATA%\erdtree\.erdtree.toml
+```
+
+[Here](examples/.erdtree.toml) and below is an example of a valid `.erdtree.toml`:
+
+```toml
+icons = true
+human = true
+
+# Compute file sizes like `du`
+# e.g. `erd --config du`
+[du]
+disk_usage = "block"
+icons = true
+layout = "flat"
+no-ignore = true
+no-git = true
+hidden = true
+level = 1
+
+# Do as `ls -l`
+# e.g. `erd --config ls`
+[ls]
+icons = true
+human = true
+level = 1
+suppress-size = true
+long = true
+
+# How many lines of Rust are in this code base?
+# e.g. `erd --config rs`
+[rs]
+disk-usage = "word"
+level = 1
+pattern = "\\.rs$"
+```
+
+`.erdtree.toml` supports multiple configurations. The top-level table is the main config that will be applied without additional arguments.
+If you wish to use a separate configuration, create a named table like `du` above, set your arguments, and invoke it like so:
+
+```
+$ erd --config du
+
+# equivalent to
+
+$ erd --disk-usage block --icons --layout flat --no-ignore --no-git --hidden --level 1
+```
+
+As far as the arguments go there are only three rules you need to be aware of:
+1. `.erdtree.toml` only accepts long-named arguments without the preceding "--".
+2. Types are enforced, so numbers are expected to be numbers, booleans are expected to be booleans, strings are expected to be strings, and so on and so forth.
+3. `snake_case` and `kebap-case` works.
+
+#### .erdtreerc
+
 `erdtree` will look for a configuration file in any of the following locations:
 
 On Linux/Mac/Unix-like:
@@ -333,24 +409,11 @@ The format of a config file is as follows:
 - Every line is an `erdtree` option/argument.
 - Lines starting with `#` are considered comments and are thus ignored.
 
-Arguments passed to `erdtree` take precedence. If you have a config that you would like to ignore without deleting you can use `--no-config`.
+Arguments passed to `erdtree` on the command-line will override those found in `.erdtreerc`.
 
-Here is an example of a valid configuration file:
-
-```
-# Long argument
---icons
---human
+[Click here](example/.erdtreerc) for an example `.erdtreerc`.
 
-# or short argument
--l
-
-# args can be passed like this
--d logical
-
-# or like this
---unit=si
-```
+**If you have a config that you would like to ignore without deleting you can use `--no-config`.**
 
 ### Hardlinks
 
diff --git a/example/.erdtree.toml b/example/.erdtree.toml
new file mode 100644
index 00000000..a409e1bb
--- /dev/null
+++ b/example/.erdtree.toml
@@ -0,0 +1,26 @@
+icons = true
+human = true
+
+# Compute file sizes like `du`
+[du]
+disk_usage = "block"
+icons = true
+layout = "flat"
+no-ignore = true
+no-git = true
+hidden = true
+level = 1
+
+# Do as `ls -l`
+[ls]
+icons = true
+human = true
+level = 1
+suppress-size = true
+long = true
+
+# How many lines of Rust are in this code base?
+[rs]
+disk-usage = "word"
+level = 1
+pattern = "\\.rs$"
diff --git a/example/.erdtreerc b/example/.erdtreerc
new file mode 100644
index 00000000..184b15ef
--- /dev/null
+++ b/example/.erdtreerc
@@ -0,0 +1,9 @@
+# Long argument
+--icons
+--human
+
+# or short argument
+-l
+
+# args can be passed like this
+-d logical
diff --git a/src/context/config/toml/mod.rs b/src/context/config/toml/mod.rs
index bb6722be..f27f6dc9 100644
--- a/src/context/config/toml/mod.rs
+++ b/src/context/config/toml/mod.rs
@@ -23,7 +23,7 @@ enum ArgInstructions {
     Pass,
 }
 
-/// Takes in a `Config` that is generated from [`load_toml`] returning a `Vec<OsString>` which
+/// Takes in a `Config` that is generated from [`load`] returning a `Vec<OsString>` which
 /// represents command-line arguments from `.erdtree.toml`. If a `nested_table` is provided then
 /// the top-level table in `.erdtree.toml` is ignored and the configurations specified in the
 /// `nested_table` will be used instead.
@@ -122,6 +122,7 @@ fn parse_argument(keyword: &str, arg: &Value) -> Result<ArgInstructions, Error>
     }
 }
 
+/// Concerned with how to load `.erdtree.toml` on Unix systems.
 #[cfg(unix)]
 mod unix {
     use super::super::{CONFIG_DIR, ERDTREE_CONFIG_TOML, ERDTREE_DIR, HOME, XDG_CONFIG_HOME};
@@ -193,6 +194,7 @@ mod unix {
     }
 }
 
+/// Concerned with how to load `.erdtree.toml` on Windows.
 #[cfg(windows)]
 mod windows {
     use super::super::{ERDTREE_CONFIG_TOML, ERDTREE_DIR};
@@ -200,13 +202,13 @@ mod windows {
     use std::{env, path::PathBuf};
 
     /// Try to read in config from the following location:
-    /// - `%APPDATA%/erdtree/.erdtree.toml`
+    /// - `%APPDATA%\erdtree\.erdtree.toml`
     pub(super) fn load_toml() -> Option<Config> {
         super::toml_from_env().or_else(toml_from_appdata)
     }
 
     /// Try to read in config from the following location:
-    /// - `%APPDATA%/erdtree/.erdtree.toml`
+    /// - `%APPDATA%\erdtree\.erdtree.toml`
     fn toml_from_appdata() -> Option<Config> {
         let app_data = dirs::config_dir()?;
 

From 7724e5d0115bdccd68c018c5d7abc3ddb7e60589 Mon Sep 17 00:00:00 2001
From: Benjamin Nguyen <benjamin.van.nguyen@gmail.com>
Date: Sun, 25 Jun 2023 21:57:55 -0700
Subject: [PATCH 6/8] README

---
 README.md | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 219aae3c..027f5c4c 100644
--- a/README.md
+++ b/README.md
@@ -28,6 +28,8 @@ You can think of `erdtree` as a little bit of `du`, `tree`, `find`, `wc` and `ls
 * [Installation](#installation)
 * [Documentation](#documentation)
   - [Configuration file](#configuration-file)
+      - [.erdtree.toml](#.erdtree.toml)
+      - [.erdtreerc](#.erdtreerc)
   - [Hardlinks](#hardlinks)
   - [Symlinks](#symlinks)
   - [Disk usage](#disk-usage)
@@ -340,7 +342,7 @@ On Windows:
 %APPDATA%\erdtree\.erdtree.toml
 ```
 
-[Here](examples/.erdtree.toml) and below is an example of a valid `.erdtree.toml`:
+[Here](example/.erdtree.toml) and below is an example of a valid `.erdtree.toml`:
 
 ```toml
 icons = true

From bf1156c6c79ae7e70e108feeaf125f9e6c38b7ae Mon Sep 17 00:00:00 2001
From: Benjamin Nguyen <benjamin.van.nguyen@gmail.com>
Date: Sun, 25 Jun 2023 21:59:10 -0700
Subject: [PATCH 7/8] README

---
 README.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 027f5c4c..75c76253 100644
--- a/README.md
+++ b/README.md
@@ -28,8 +28,8 @@ You can think of `erdtree` as a little bit of `du`, `tree`, `find`, `wc` and `ls
 * [Installation](#installation)
 * [Documentation](#documentation)
   - [Configuration file](#configuration-file)
-      - [.erdtree.toml](#.erdtree.toml)
-      - [.erdtreerc](#.erdtreerc)
+      - [.erdtree.toml](#erdtree.toml)
+      - [.erdtreerc](#erdtreerc)
   - [Hardlinks](#hardlinks)
   - [Symlinks](#symlinks)
   - [Disk usage](#disk-usage)

From 6cc476abb447b3ac4fc53d236397cc83ed02d51e Mon Sep 17 00:00:00 2001
From: Benji Nguyen <45523555+solidiquis@users.noreply.github.com>
Date: Sun, 25 Jun 2023 22:02:15 -0700
Subject: [PATCH 8/8] Update README.md

---
 README.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 75c76253..85d73185 100644
--- a/README.md
+++ b/README.md
@@ -28,7 +28,7 @@ You can think of `erdtree` as a little bit of `du`, `tree`, `find`, `wc` and `ls
 * [Installation](#installation)
 * [Documentation](#documentation)
   - [Configuration file](#configuration-file)
-      - [.erdtree.toml](#erdtree.toml)
+      - [Toml file](#toml-file)
       - [.erdtreerc](#erdtreerc)
   - [Hardlinks](#hardlinks)
   - [Symlinks](#symlinks)
@@ -322,7 +322,7 @@ The configuration file currently comes in two flavors: `.erdtreerc` (to be depre
 `.erdtreerc` will take precedent and `.erdtree.toml` will be disregarded, but please **note that `.erdtreerc` will be deprecated in the near future.** There is
 no reason to have both.
 
-#### .erdtree.toml
+#### TOML file
 
 `erdtree` will look for `.erdtree.toml in any of the following locations: