add cwd docs and RUST_TARGET

cli/README.md

@@ -66,6 +66,8 @@ If not set, cli will read the `package.name` field in `Cargo.toml` under `proces
 
 > default `undefined`
 
+You can also define this value using the `RUST_TARGET` environment variable.
+
 This value will be passed to `Cargo build` command directly. eg: `napi build --target x86_64-unknown-linux-musl`
 
 #### `--cargo-flags`
@@ -74,6 +76,12 @@ This value will be passed to `Cargo build` command directly. eg: `napi build --t
 
 Other flags you want pass to `Cargo build`.
 
+#### `--cargo-cwd`
+
+> default `undefined`
+
+This flag can be used to build binaries that are not in the current directory. The path that is passed to this flag should be relative to the current directory.
+
 ### `napi artifacts`
 
 > Copy artifact files in Github actions.

cli/src/build.ts

@@ -30,7 +30,7 @@ export class BuildCommand extends Command {
   cargoName?: string
 
   @Command.String('--target')
-  targetTripleDir = ''
+  targetTripleDir = process.env.RUST_TARGET ?? ''
 
   @Command.String('--features')
   features?: string