Read font path from environment variables (typst#649)

Author: michidk

README.md

@@ -149,6 +149,9 @@ typst --font-path path/to/fonts compile file.typ
 
 # Lists all of the discovered fonts in the system and the given directory.
 typst --font-path path/to/fonts fonts
+
+# Or via environement variable (Linux syntax).
+TYPST_FONT_PATHS=path/to/fonts typst fonts
 ```
 
 If you prefer an integrated IDE-like experience with autocompletion and instant

cli/Cargo.toml

@@ -32,7 +32,7 @@ once_cell = "1"
 same-file = "1"
 siphasher = "0.3"
 walkdir = "2"
-clap = { version = "4.2.1", features = ["derive"] }
+clap = { version = "4.2.1", features = ["derive", "env"] }
 open = "4.0.1"
 
 [build-dependencies]

cli/src/args.rs

@@ -7,11 +7,11 @@ use clap::{ArgAction, Parser, Subcommand};
 #[clap(name = "typst", version = crate::typst_version(), author)]
 pub struct CliArguments {
     /// Add additional directories to search for fonts
-    #[clap(long = "font-path", value_name = "DIR", action = ArgAction::Append)]
+    #[clap(long = "font-path", env = "TYPST_FONT_PATHS", value_name = "DIR", action = ArgAction::Append)]
     pub font_paths: Vec<PathBuf>,
 
     /// Configure the root for absolute paths
-    #[clap(long = "root", value_name = "DIR")]
+    #[clap(long = "root", env = "TYPST_ROOT", value_name = "DIR")]
     pub root: Option<PathBuf>,
 
     /// The typst command to run