Add swift-bootstrap command (#5860)

This command can be used to bootstrap SwiftPM via CMake without requiring us to build a full-blown SwiftPM using CMake.

Author: neonichu

Package.swift

@@ -385,6 +385,12 @@ let package = Package(
             dependencies: ["Commands"],
             exclude: ["CMakeLists.txt"]
         ),
+        .executableTarget(
+            /** Builds SwiftPM itself for bootstrapping (minimal version of `swift-build`) */
+            name: "swift-bootstrap",
+            dependencies: ["CoreCommands"],
+            exclude: ["CMakeLists.txt"]
+        ),
         .executableTarget(
             /** Runs package tests */
             name: "swift-test",

Sources/CMakeLists.txt

@@ -27,6 +27,7 @@ add_subdirectory(PackageRegistry)
 add_subdirectory(SPMBuildCore)
 add_subdirectory(SPMLLBuild)
 add_subdirectory(SourceControl)
+add_subdirectory(swift-bootstrap)
 add_subdirectory(swift-build)
 add_subdirectory(swift-package)
 add_subdirectory(swift-run)

Sources/Workspace/CMakeLists.txt

@@ -32,6 +32,7 @@ target_link_libraries(Workspace PUBLIC
   PackageGraph
   PackageLoading
   PackageModel
+  PackageRegistry
   SourceControl)
 target_link_libraries(PackageLoading PUBLIC
   $<$<NOT:$<PLATFORM_ID:Darwin>>:Foundation>)

Sources/swift-bootstrap/CMakeLists.txt

@@ -0,0 +1,12 @@
+# This source file is part of the Swift open source project
+#
+# Copyright (c) 2022 Apple Inc. and the Swift project authors
+# Licensed under Apache License v2.0 with Runtime Library Exception
+#
+# See http://swift.org/LICENSE.txt for license information
+# See http://swift.org/CONTRIBUTORS.txt for Swift project authors
+
+add_executable(swift-bootstrap
+    main.swift)
+target_link_libraries(swift-bootstrap PRIVATE
+    CoreCommands)

Sources/swift-bootstrap/main.swift

@@ -0,0 +1,15 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift open source project
+//
+// Copyright (c) 2022 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See http://swift.org/LICENSE.txt for license information
+// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+import CoreCommands
+
+SwiftMinimalBuildTool.main()

Utilities/bootstrap

@@ -483,7 +483,7 @@ def install_binary(args, binary, dest_dir, ignored_patterns=[]):
 # Build functions
 # -----------------------------------------------------------
 
-def build_with_cmake(args, cmake_args, source_path, build_dir):
+def build_with_cmake(args, cmake_args, ninja_args, source_path, build_dir):
     """Runs CMake if needed, then builds with Ninja."""
     cache_path = os.path.join(build_dir, "CMakeCache.txt")
     if args.reconfigure or not os.path.isfile(cache_path) or not args.swiftc_path in open(cache_path).read():
@@ -514,7 +514,8 @@ def build_with_cmake(args, cmake_args, source_path, build_dir):
     if args.verbose:
         ninja_cmd.append("-v")
 
-    call(ninja_cmd, cwd=build_dir, verbose=args.verbose)
+
+    call(ninja_cmd + ninja_args, cwd=build_dir, verbose=args.verbose)
 
 def build_llbuild(args):
     """Builds LLBuild using CMake."""
@@ -541,7 +542,7 @@ def build_llbuild(args):
         flags.append("-DSQLite3_INCLUDE_DIR=%s/usr/include" % args.sysroot)
 
     args.source_dirs["llbuild"] = get_llbuild_source_path(args)
-    build_with_cmake(args, flags, args.source_dirs["llbuild"], args.build_dirs["llbuild"])
+    build_with_cmake(args, flags, [], args.source_dirs["llbuild"], args.build_dirs["llbuild"])
 
 def build_dependency(args, target_name, common_cmake_flags = [], non_darwin_cmake_flags = []):
     note("Building " + target_name)
@@ -554,11 +555,11 @@ def build_dependency(args, target_name, common_cmake_flags = [], non_darwin_cmak
     else:
         cmake_flags += non_darwin_cmake_flags
 
-    build_with_cmake(args, cmake_flags, args.source_dirs[target_name], args.build_dirs[target_name])
+    build_with_cmake(args, cmake_flags, [], args.source_dirs[target_name], args.build_dirs[target_name])
 
 def add_rpath_for_cmake_build(args, rpath):
-    "Adds the given rpath to the CMake-built swift-build"
-    swift_build = os.path.join(args.bootstrap_dir, "bin/swift-build")
+    "Adds the given rpath to the CMake-built swift-bootstrap"
+    swift_build = os.path.join(args.bootstrap_dir, "bin/swift-bootstrap")
     add_rpath_cmd = ["install_name_tool", "-add_rpath", rpath, swift_build]
     note(' '.join(add_rpath_cmd))
     subprocess.call(add_rpath_cmd, stderr=subprocess.PIPE)
@@ -594,7 +595,7 @@ def build_swiftpm_with_cmake(args):
         cmake_flags.append("-DCMAKE_C_FLAGS=-target %s%s" % (get_build_target(args), g_macos_deployment_target))
         cmake_flags.append("-DCMAKE_OSX_DEPLOYMENT_TARGET=%s" % g_macos_deployment_target)
 
-    build_with_cmake(args, cmake_flags, args.project_root, args.bootstrap_dir)
+    build_with_cmake(args, cmake_flags, ["swift-bootstrap", "PackageDescription", "PackagePlugin"], args.project_root, args.bootstrap_dir)
 
     if args.llbuild_link_framework:
         add_rpath_for_cmake_build(args, args.build_dirs["llbuild"])
@@ -620,9 +621,9 @@ def build_swiftpm_with_swiftpm(args, integrated_swift_driver):
     ]
 
     if args.bootstrap:
-        note("Building SwiftPM (with a freshly built swift-build)")
+        note("Building SwiftPM (with a freshly built swift-bootstrap)")
         swiftpm_args.append("SWIFTPM_CUSTOM_LIBS_DIR=" + os.path.join(args.bootstrap_dir, "pm"))
-        swiftpm_args.append(os.path.join(args.bootstrap_dir, "bin/swift-build"))
+        swiftpm_args.append(os.path.join(args.bootstrap_dir, "bin/swift-bootstrap"))
     else:
         note("Building SwiftPM (with a prebuilt swift-build)")
         swiftpm_args.append(os.path.join(os.path.split(args.swiftc_path)[0], "swift-build"))