feat: support for parsing environment variables (#44)

Author: koyashiro

Diff for: Cargo.toml

@@ -13,7 +13,7 @@ categories = ["command-line-utilities"]
 
 [dependencies]
 anyhow = "1.0.70"
-clap = { version = "4.2.4", features = ["derive", "cargo"] }
+clap = { version = "4.2.4", features = ["derive", "cargo", "env"] }
 dirs = "5.0.0"
 octocrab = { version = "0.19.0", default-features = false, features = ["rustls-tls"] }
 regex = "1.8.1"

Diff for: src/args.rs

@@ -7,21 +7,21 @@ pub const STDIN: &str = "-";
 #[derive(Debug, Parser)]
 #[command(author, version, about, long_about = None)]
 pub struct Args {
-    #[arg(long, default_value = "")]
+    #[arg(long, env, default_value = "")]
     pub name: String,
 
-    #[arg(long, default_value = "")]
+    #[arg(long, env, default_value = "")]
     pub author: String,
 
-    #[arg(long, default_value = "")]
+    #[arg(long, env, default_value = "")]
     pub url: String,
 
-    #[arg(long, default_value = "")]
+    #[arg(long, env, default_value = "")]
     pub id: String,
 
-    #[arg(long, value_delimiter = ',')]
+    #[arg(long, env, value_delimiter = ',')]
     pub repos: Vec<GitHubRepo>,
 
-    #[arg(long, short, default_value = STDIN)]
+    #[arg(long, short, env, default_value = STDIN)]
     pub output: String,
 }