Add parse-bridges CLI subcommand

book/src/building/swiftc-and-cargo/README.md

@@ -70,7 +70,7 @@ func run() {
 ```
 
 ```sh
-# briding-header.h
+# bridging-header.h
 
 #ifndef BridgingHeader_h
 #define BridgingHeader_h
@@ -134,25 +134,13 @@ chmod +x build-swiftc-links-rust.sh
 
 ## Rust links to a Swift native library
 
-Unlike the when we had `swiftc` in the Rust code, you do not need to set the `crate-type`
+Unlike when we had `swiftc` linking in the Rust code, you do not need to set the `crate-type`
 when you have `Cargo` linking in the Swift code.
 
 ```rust
 // build.rs
-use std::path::PathBuf;
-
 fn main() {
-    let out_dir = PathBuf::from("./generated");
-
-    let bridges = vec!["src/lib.rs"];
-    for path in &bridges {
-        println!("cargo:rerun-if-changed={}", path);
-    }
-
-    swift_bridge_build::parse_bridges(bridges)
-        .write_all_concatenated(out_dir, env!("CARGO_PKG_NAME"));
-
-    println!("cargo:rustc-link-lib=static=swiftc_link_rust");
+    println!("cargo:rustc-link-lib=static=my_swift");
     println!("cargo:rustc-link-search=./");
 }
 ```
@@ -163,9 +151,10 @@ fn main() {
 #!/bin/bash
 set -e
 
-# The swift-bridge CLI does not exist yet. Open an issue if you need to use
-# this approach and I'll happily whip up the CLI.
-swift-bridge -f src/lib.rs > generated
+# Generate the bridging headers.
+# Multiple files can be supplied with "-f" flag, e.g. "-f file1 -f file2".
+# Substitute <package name> for the crate name in your Cargo.toml file.
+swift-bridge-cli parse-bridges --crate-name <package name> -f src/lib.rs -o generated
 
 swiftc -emit-library -static -module-name my_swift -import-objc-header bridging-header.h \
   lib.swift ./generated/swift-and-rust/swift-and-rust.swift

crates/swift-bridge-cli/src/clap_app.rs

@@ -1,4 +1,4 @@
-use clap::{Arg, Command};
+use clap::{Arg, ArgAction, Command};
 
 /// The CLI application
 pub fn cli() -> Command<'static> {
@@ -7,6 +7,7 @@ pub fn cli() -> Command<'static> {
         .version(env!("CARGO_PKG_VERSION"))
         .subcommand_required(true)
         .subcommand(create_package_command())
+        .subcommand(create_bridges_command())
 }
 
 /// The command for creating a Swift Package
@@ -101,3 +102,35 @@ fn create_package_command() -> Command<'static> {
                 .help("The name for the Swift Package"),
         )
 }
+
+fn create_bridges_command() -> Command<'static> {
+    Command::new("parse-bridges")
+        .about("Parse bridge library files and output generated headers")
+        .arg(
+            Arg::new("crate-name")
+                .action(ArgAction::Set)
+                .help(
+                    "Crate name for which the bridging headers are generated; \
+                          used as a part of header names",
+                )
+                .long("--crate-name")
+                .required(true),
+        )
+        .arg(
+            Arg::new("source-file")
+                .action(ArgAction::Append)
+                .help("source file(s) containing #[swift_bridge::bridge] macro")
+                .long("file")
+                .short('f')
+                .required(true),
+        )
+        .arg(
+            Arg::new("output")
+                .action(ArgAction::Set)
+                .help("Output destination folder")
+                .long("output")
+                .short('o')
+                .value_name("PATH")
+                .required(true),
+        )
+}

crates/swift-bridge-cli/src/clap_exec.rs

@@ -1,13 +1,16 @@
 use clap::ArgMatches;
 use std::collections::HashMap;
 use std::path::{Path, PathBuf};
-use swift_bridge_build::{create_package, ApplePlatform, CreatePackageConfig};
+use swift_bridge_build::{create_package, parse_bridges, ApplePlatform, CreatePackageConfig};
 
 /// Executes the correct function depending on the cli input
 pub fn handle_matches(matches: ArgMatches) {
     match matches.subcommand_name() {
-        Some("create-package") => {
-            handle_create_package(matches.subcommand_matches("create-package").unwrap())
+        Some(cmd @ "create-package") => {
+            handle_create_package(matches.subcommand_matches(cmd).unwrap())
+        }
+        Some(cmd @ "parse-bridges") => {
+            handle_parse_bridges(matches.subcommand_matches(cmd).unwrap())
         }
         _ => unreachable!("No subcommand or unknown subcommand given"), // Shouldn't happen
     }
@@ -16,7 +19,7 @@ pub fn handle_matches(matches: ArgMatches) {
 /// Executes the `create-package` command
 fn handle_create_package(matches: &ArgMatches) {
     let bridges_dir = matches.value_of("bridges-dir").unwrap(); // required
-    let out_dir = matches.value_of("out-dir").map(|p| Path::new(p)).unwrap(); // required
+    let out_dir = matches.value_of("out-dir").map(Path::new).unwrap(); // required
     let name = matches.value_of("name").unwrap(); // required
 
     let mut config = CreatePackageConfig {
@@ -34,3 +37,12 @@ fn handle_create_package(matches: &ArgMatches) {
 
     create_package(config);
 }
+
+/// Executes the `parse-bridges` command
+fn handle_parse_bridges(matches: &ArgMatches) {
+    let crate_name = matches.get_one::<String>("crate-name").unwrap(); // required
+    let source_files: Vec<&String> = matches.get_many("source-file").unwrap().collect(); // required
+    let output = matches.get_one::<String>("output").map(Path::new).unwrap(); // required
+
+    parse_bridges(source_files.iter().map(Path::new)).write_all_concatenated(output, crate_name);
+}

crates/swift-bridge-macro/tests/ui/args-into-argument-not-found.rs

@@ -15,12 +15,12 @@ mod ffi {
     }
 }
 
-fn some_function(arg: u8) {}
+fn some_function(_arg: u8) {}
 
 struct SomeType;
 
 impl SomeType {
-    fn some_method(&self, foo: u8) {}
+    fn some_method(&self, _foo: u8) {}
 }
 
 fn main() {}