[build-script] Build XCTest's Foundation dependency

As of swiftlang/swift-corelibs-xctest#43,
swift-corelibs-xctest is dependent upon swift-corelibs-foundation.
As such, it must be built after Foundation, and its build
script must be passed a reference to the Foundation build
directory. Update the build script in order to get XCTest
building after the changes in swiftlang/swift-corelibs-xctest#43.

In addition, this change also allows XCTest to be tested via
`utils/build-script --xctest --test`. This has been possible
since swiftlang/swift-corelibs-xctest#46.

Author: modocache

utils/build-script

@@ -14,6 +14,7 @@ from __future__ import print_function
 import argparse
 import multiprocessing
 import os
+import platform
 import shutil
 import sys
 import textwrap
@@ -566,6 +567,12 @@ the number of parallel build jobs to use""",
     if (args.lldb_build_variant is not None or args.lldb_assertions is not None):
         args.build_lldb = True
 
+    # If XCTest is to be built on systems other than OS X, its dependency
+    # Foundation must also be built. This isn't necessary on OS X, since
+    # Foundation is built via xcodebuild.
+    if platform.system() != 'Darwin' and args.build_xctest:
+      args.build_foundation = True
+
     # Set the default build variant.
     if args.build_variant is None:
         args.build_variant = "Debug"

utils/build-script-impl

@@ -921,12 +921,14 @@ fi
 if [[ ! "${SKIP_BUILD_SWIFTPM}" ]] ; then
      PRODUCTS=("${PRODUCTS[@]}" swiftpm)
 fi
-if [[ ! "${SKIP_BUILD_XCTEST}" ]] ; then
-     PRODUCTS=("${PRODUCTS[@]}" xctest)
-fi
+# XCTest has a dependency upon Foundation. It must be added to the list of
+# products *after* Foundation.
 if [[ ! "${SKIP_BUILD_FOUNDATION}" ]] ; then
      PRODUCTS=("${PRODUCTS[@]}" foundation)
 fi
+if [[ ! "${SKIP_BUILD_XCTEST}" ]] ; then
+     PRODUCTS=("${PRODUCTS[@]}" xctest)
+fi
 if [[ ! "${SKIP_BUILD_LIBDISPATCH}" ]] ; then
      PRODUCTS=("${PRODUCTS[@]}" libdispatch)
 fi
@@ -1796,16 +1798,6 @@ for deployment_target in "${HOST_TARGET}" "${CROSS_TOOLS_DEPLOYMENT_TARGETS[@]}"
                 # swiftpm installs itself with a bootstrap method. No further cmake building is performed.
                 continue
                 ;;
-            xctest)
-                SWIFTC_BIN="$(build_directory_bin ${deployment_target} swift)/swiftc"
-                SWIFT_BUILD_PATH="$(build_directory ${deployment_target} swift)"
-                set -x
-                "${XCTEST_SOURCE_DIR}"/build_script.py --swiftc="${SWIFTC_BIN}" --build-dir="${build_dir}" --swift-build-dir="${SWIFT_BUILD_PATH}"
-                { set +x; } 2>/dev/null
-
-                # XCTest builds itself and doesn't rely on cmake
-                continue
-                ;;
             foundation)
                 # the configuration script requires knowing about XCTest's location for building and running the tests
                 XCTEST_BUILD_DIR=$(build_directory ${deployment_target} xctest)
@@ -1831,6 +1823,23 @@ for deployment_target in "${HOST_TARGET}" "${CROSS_TOOLS_DEPLOYMENT_TARGETS[@]}"
                 # Foundation builds itself and doesn't use cmake
                 continue
                 ;;
+            xctest)
+                if [[ "$(uname -s)" == "Darwin" ]] ; then
+                    set -x
+                    xcodebuild -project "${XCTEST_SOURCE_DIR}"/XCTest.xcodeproj -scheme SwiftXCTest SKIP_INSTALL=NO DEPLOYMENT_LOCATION=YES DSTROOT="${build_dir}" INSTALL_PATH="/"
+                    { set +x; } 2>/dev/null
+                else
+                    SWIFTC_BIN="$(build_directory_bin ${deployment_target} swift)/swiftc"
+                    SWIFT_BUILD_PATH="$(build_directory ${deployment_target} swift)"
+                    FOUNDATION_BUILD_DIR="$(build_directory ${deployment_target} foundation)"/Foundation
+                    set -x
+                    "${XCTEST_SOURCE_DIR}"/build_script.py --swiftc="${SWIFTC_BIN}" --build-dir="${build_dir}" --swift-build-dir="${SWIFT_BUILD_PATH}" --foundation-build-dir="${FOUNDATION_BUILD_DIR}"
+                    { set +x; } 2>/dev/null
+                fi
+
+                # XCTest builds itself and doesn't rely on cmake
+                continue
+                ;;
             libdispatch)
                 LIBDISPATCH_BUILD_DIR=$(build_directory ${deployment_target} ${product})
 
@@ -2017,13 +2026,6 @@ for deployment_target in "${STDLIB_DEPLOYMENT_TARGETS[@]}"; do
                 # As swiftpm tests itself, we break early here.
                 continue
                 ;;
-            xctest)
-                if [[ "${SKIP_TEST_XCTEST}" ]]; then
-                    continue
-                fi
-                # FIXME: We don't test xctest, yet...
-                continue
-                ;;
             foundation)
                 if [[ "${SKIP_TEST_FOUNDATION}" ]]; then
                     continue
@@ -2040,6 +2042,28 @@ for deployment_target in "${STDLIB_DEPLOYMENT_TARGETS[@]}"; do
                 echo "--- Finished tests for ${product} ---"
                 continue
                 ;;
+            xctest)
+                if [[ "${SKIP_TEST_XCTEST}" ]]; then
+                    continue
+                fi
+                echo "--- Running tests for ${product} ---"
+                if [[ "$(uname -s)" == "Darwin" ]] ; then
+                    set -x
+                    xcodebuild -project "${XCTEST_SOURCE_DIR}"/XCTest.xcodeproj -scheme SwiftXCTestFunctionalTests
+                    { set +x; } 2>/dev/null
+                else
+                    SWIFTC_BIN="$(build_directory_bin ${deployment_target} swift)/swiftc"
+                    SWIFT_BUILD_PATH="$(build_directory ${deployment_target} swift)"
+                    FOUNDATION_BUILD_PATH="$(build_directory ${deployment_target} foundation)"/Foundation
+                    set -x
+                    # FIXME: This re-builds swift-corelibs-xctest. Instead, 'build_script.py' should take
+                    # a top-level 'test' command that only tests an already built XCTest.
+                    "${XCTEST_SOURCE_DIR}"/build_script.py --swiftc="${SWIFTC_BIN}" --build-dir="${build_dir}" --swift-build-dir="${SWIFT_BUILD_PATH}" --foundation-build-dir="${FOUNDATION_BUILD_PATH}" --test
+                    { set +x; } 2>/dev/null
+                fi
+                echo "--- Finished tests for ${product} ---"
+                continue
+                ;;
             libdispatch)
                 if [[ "${SKIP_TEST_LIBDISPATCH}" ]]; then
                     continue