wip: hot reloading

Package.swift

@@ -23,7 +23,7 @@ let package = Package(
     name: "xtool",
     platforms: [
         .iOS(.v16),
-        .macOS(.v13),
+        .macOS(.v14),
     ],
     products: [
         .library(
@@ -56,6 +56,7 @@ let package = Package(
 
         .package(url: "https://github.com/swiftlang/swift-docc-plugin", from: "1.0.0"),
         .package(url: "https://github.com/swiftlang/swift-subprocess", .upToNextMinor(from: "0.4.0")),
+        .package(url: "https://github.com/swiftlang/swift-tools-protocols", exact: "0.0.10"),
 
         .package(url: "https://github.com/swift-server/async-http-client.git", from: "1.23.0"),
         .package(url: "https://github.com/swift-server/swift-openapi-async-http-client", from: "1.0.0"),
@@ -159,6 +160,7 @@ let package = Package(
                 .product(name: "NIOPosix", package: "swift-nio"),
                 .product(name: "Version", package: "Version"),
                 .product(name: "libunxip", package: "unxip"),
+                .product(name: "LanguageServerProtocolTransport", package: "swift-tools-protocols"),
             ],
             cSettings: cSettings
         ),

Sources/CXKit/include/CXKit.h

@@ -0,0 +1,4 @@
+#include "inotify_shim.h"
+#include "stdout_shim.h"
+#include "version.h"
+#include "mobileprovision.h"

Sources/CXKit/include/inotify_shim.h

@@ -0,0 +1,21 @@
+#ifndef CINOTIFY_SHIMS_H
+#define CINOTIFY_SHIMS_H
+
+#ifdef __linux__
+
+#include <stdio.h>
+#include <stdint.h>
+#include <sys/inotify.h>
+
+static inline const char *cin_event_name(const struct inotify_event *event) {
+	if (event->len)
+		return event->name;
+	else
+		return NULL;
+}
+
+static const uint32_t cin_all_events = IN_ALL_EVENTS;
+
+#endif
+
+#endif /* CINOTIFY_SHIMS_H */

Sources/PackLib/BuildSettings.swift

@@ -1,6 +1,7 @@
 import Foundation
 import Subprocess
 import XUtils
+import Superutils
 
 public struct BuildSettings: Sendable {
     private static let customBinDir =
@@ -44,9 +45,29 @@ public struct BuildSettings: Sendable {
         return result.standardOutput?.trimmingCharacters(in: .whitespacesAndNewlines) ?? ""
     }
 
-    private static let swiftURL = Task {
+    private static let _swiftURL = Task {
         try await FilePath(xcrun(["-f", "swift"]))
     }
+
+    public static func swiftURL() async throws -> FilePath {
+        try await _swiftURL.value
+    }
+
+    private static let _swiftcURL = Task {
+        try await FilePath(xcrun(["-f", "swiftc"]))
+    }
+
+    public static func swiftcURL() async throws -> FilePath {
+        try await _swiftcURL.value
+    }
+    #else
+    public static func swiftURL() async throws -> FilePath {
+        try await FilePath(ToolRegistry.locate("swift")).orThrow(StringError("Got bad path for swift executable"))
+    }
+
+    public static func swiftcURL() async throws -> FilePath {
+        try await FilePath(ToolRegistry.locate("swiftc")).orThrow(StringError("Got bad path for swiftc executable"))
+    }
     #endif
 
     public func swiftPMInvocation(
@@ -66,7 +87,7 @@ public struct BuildSettings: Sendable {
             // 1) invoking the real swift executable (located with `xcrun -f`) and
             // 2) explicitly removing SDKROOT from the env, as it may be inherited
             // through the `swift run pack` invocation.
-            executable = .path(try await Self.swiftURL.value)
+            executable = .path(try await Self.swiftURL())
             #else
             executable = .name("swift")
             #endif
@@ -78,22 +99,34 @@ public struct BuildSettings: Sendable {
             "--configuration", configuration.rawValue,
         ]
 
-        var rawEnv = ProcessInfo.processInfo.environment
-        rawEnv.removeValue(forKey: "SDKROOT")
-        let env = Dictionary(uniqueKeysWithValues: rawEnv.map {
-            (Environment.Key(rawValue: $0)!, $1)
-        })
-
         return Configuration(
             executable,
             arguments: .init(baseArguments + extraArguments + sdkOptions + options + arguments),
-            environment: .custom(env),
+            environment: .inherit.updating(["SDKROOT": nil]),
             platformOptions: .withGracefulShutDown,
         )
     }
+
+    public var buildServerArguments: [String] {
+        return [
+            "package", "experimental-build-server",
+            "--package-path", "\(FileManager.default.currentDirectoryPath)/xtool/.xtool-tmp",
+            "--build-system", "swiftbuild",
+            "--disable-automatic-resolution",
+            // TODO: once https://github.com/swiftlang/swift-package-manager/pull/9819 makes it into a release
+            // (Swift 6.4), pass --experimental-skip-acquiring-lock
+        ] + sdkOptions + options
+    }
 }
 
 public enum BuildConfiguration: String, CaseIterable, Sendable {
     case debug
     case release
+
+    var swiftBuildValue: String {
+        switch self {
+        case .debug: "Debug"
+        case .release: "Release"
+        }
+    }
 }

Sources/PackLib/Packer.swift

@@ -3,12 +3,38 @@ import XUtils
 import Subprocess
 
 public struct Packer: Sendable {
+    public enum BuildSystem: Sendable {
+        case swiftPM
+        case swiftBuild
+
+        public static var `default`: Self {
+            #if os(macOS)
+            return .swiftBuild
+            #else
+            return .swiftPM
+            #endif
+        }
+
+        fileprivate var pmName: String {
+            switch self {
+            case .swiftPM: "native"
+            case .swiftBuild: "swiftbuild"
+            }
+        }
+    }
+
     public let buildSettings: BuildSettings
     public let plan: Plan
+    public let buildSystem: BuildSystem
 
-    public init(buildSettings: BuildSettings, plan: Plan) {
+    public init(
+        buildSettings: BuildSettings,
+        plan: Plan,
+        buildSystem: BuildSystem = .default,
+    ) {
         self.plan = plan
         self.buildSettings = buildSettings
+        self.buildSystem = buildSystem
     }
 
     private func build() async throws {
@@ -67,6 +93,7 @@ public struct Packer: Sendable {
                 // in order to dump the plan, so we can skip resolution here to skirt
                 // the issue.
                 "--disable-automatic-resolution",
+                "--build-system", buildSystem.pmName,
             ]
         )
         try await Subprocess.run(
@@ -83,8 +110,16 @@ public struct Packer: Sendable {
 
         let outputURL = output.url
 
+        let binPath: String
+        switch buildSystem {
+        case .swiftPM:
+            binPath = "\(buildSettings.triple)/\(buildSettings.configuration.rawValue)"
+        case .swiftBuild:
+            let platformName = buildSettings.triple.contains("simulator") ? "iphonesimulator" : "iphoneos"
+            binPath = "out/Products/\(buildSettings.configuration.swiftBuildValue)-\(platformName)"
+        }
         let binDir = URL(
-            fileURLWithPath: ".build/\(buildSettings.triple)/\(buildSettings.configuration.rawValue)",
+            fileURLWithPath: ".build/\(binPath)",
             isDirectory: true
         )
 

Sources/XToolSupport/DevBSPCommand.swift

@@ -0,0 +1,30 @@
+import ArgumentParser
+import Foundation
+import XKit
+import PackLib
+import Subprocess
+
+struct DevBSPCommand: AsyncParsableCommand {
+    static let configuration = CommandConfiguration(
+        commandName: "build-server",
+        abstract: "Run build server",
+    )
+
+    @Option
+    var triple: String?
+
+    func run() async throws {
+        let settings = try await BuildSettings(
+            configuration: .debug,
+            triple: triple ?? PackOperation.defaultTriple
+        )
+        try await Subprocess.run(
+            .path(BuildSettings.swiftURL()),
+            arguments: .init(settings.buildServerArguments),
+            input: .standardInput,
+            output: .standardOutput,
+            error: .standardError,
+        )
+        .checkSuccess()
+    }
+}