taplo-cli: add ENV variable support

crates/taplo-cli/src/args.rs

@@ -22,6 +22,8 @@ pub struct TaploArgs {
 #[derive(Clone, Args)]
 pub struct GeneralArgs {
     /// Path to the Taplo configuration file.
+    ///
+    /// Configuration file can be specified in $TAPLO_CONFIG
     #[clap(long, short)]
     pub config: Option<PathBuf>,
 

crates/taplo-cli/src/lib.rs

@@ -2,6 +2,7 @@ use anyhow::{anyhow, Context};
 use args::GeneralArgs;
 use itertools::Itertools;
 use std::{
+    env,
     path::{Path, PathBuf},
     sync::Arc,
 };
@@ -47,7 +48,14 @@ impl<E: Environment> Taplo<E> {
 
         if config_path.is_none() && !general.no_auto_config {
             if let Some(cwd) = self.env.cwd_normalized() {
-                config_path = self.env.find_config_file_normalized(&cwd).await
+                config_path = self.env.find_config_file_normalized(&cwd).await;
+            }
+        }
+
+        if config_path.is_none() {
+            tracing::debug!("Looking for config path in the environment variable");
+            if let Ok(path) = env::var("TAPLO_CONFIG") {
+                config_path = Some(path.into());
             }
         }
 

site/site/cli/usage/configuration.md

@@ -24,3 +24,5 @@ The available log levels:
 <!-- TODO: config link -->
 
 Taplo CLI by default searches for a Taplo config file in the current working directory, this behaviour can be disabled by either supplying `--no-auto-config` or `--config <path>` flags.
+
+If a config file is not provided and no file is found in the current working directory, Taplo CLI will try to retrieve the configuration file path from the `TAPLO_CONFIG` environment variable.