Move the two extension range helpers out of Descriptor.

These two apis aren't a normal part of the C++ Descriptor api, so move them out
to the plugin level itself so they aren't public api going forward.

As of http://github.com/apple/swift-package-manager/pull/3316 tests can depend
on executable targets. The majority of this CL is then adding a new test (only
for newer SwiftPM versions) that allows the tests also to have been moved over.

.gitignore

@@ -9,7 +9,7 @@ xcbaselines
 /docs
 /build
 mined_words.txt
-/DescriptorTestData.bin
+/*DescriptorTestData.bin
 /Package.resolved
 
 # Intermediate conformance test outputs

Makefile

@@ -164,11 +164,14 @@ CONFORMANCE_PROTOS= \
 	Protos/google/protobuf/test_messages_proto2.proto \
 	Protos/google/protobuf/test_messages_proto3.proto
 
-SWIFT_DESCRIPTOR_TEST_PROTOS= \
+SWIFT_PLUGINLIB_DESCRIPTOR_TEST_PROTOS= \
 	Protos/pluginlib_descriptor_test.proto \
 	Protos/pluginlib_descriptor_test2.proto \
 	${PLUGIN_PROTOS}
 
+SWIFT_PLUGIN_DESCRIPTOR_TEST_PROTOS= \
+	Protos/plugin_descriptor_test.proto
+
 .PHONY: \
 	all \
 	build \
@@ -200,8 +203,13 @@ all: build
 
 # This generates a LinuxMain.swift to include all of the test cases.
 # It is needed for all builds before 5.4.x
+# NOTE: This doesn't include Tests/protoc-gen-swiftTests because the older
+# SwiftPM versions could have a test depend on an executable target.
 generate-linux-main:
-	@${AWK} -f DevTools/CollectTests.awk Tests/*/Test_*.swift > Tests/LinuxMain.swift.new
+	@${AWK} -f DevTools/CollectTests.awk \
+	    Tests/SwiftProtobufPluginLibraryTests/Test_*.swift \
+	    Tests/SwiftProtobufTests/Test_*.swift \
+	  > Tests/LinuxMain.swift.new
 	@if ! cmp -s Tests/LinuxMain.swift.new Tests/LinuxMain.swift; then \
 		cp Tests/LinuxMain.swift.new Tests/LinuxMain.swift; \
 		echo "FYI: Tests/LinuxMain.swift Updated"; \
@@ -222,7 +230,7 @@ install: build
 
 clean:
 	swift package clean
-	rm -rf .build _test ${PROTOC_GEN_SWIFT} DescriptorTestData.bin \
+	rm -rf .build _test ${PROTOC_GEN_SWIFT} *DescriptorTestData.bin \
 	  Performance/_generated Performance/_results Protos/mined_words.txt \
 	  docs build
 	find . -name '*~' | xargs rm -f
@@ -313,6 +321,7 @@ regenerate: \
 	regenerate-plugin-protos \
 	regenerate-test-protos \
 	regenerate-conformance-protos \
+	Tests/protoc-gen-swiftTests/DescriptorTestData.swift \
 	Tests/SwiftProtobufPluginLibraryTests/DescriptorTestData.swift
 
 # Rebuild just the protos included in the runtime library
@@ -353,20 +362,37 @@ regenerate-fuzz-protos: build ${PROTOC_GEN_SWIFT}
 		--tfiws_out=FuzzTesting/Sources/FuzzCommon \
 		Protos/fuzz_testing.proto
 
-Tests/SwiftProtobufPluginLibraryTests/DescriptorTestData.swift: build ${PROTOC_GEN_SWIFT} ${SWIFT_DESCRIPTOR_TEST_PROTOS}
+Tests/SwiftProtobufPluginLibraryTests/DescriptorTestData.swift: build ${PROTOC_GEN_SWIFT} ${SWIFT_PLUGINLIB_DESCRIPTOR_TEST_PROTOS}
+	# Until the flag isn't needed, add the flag to enable proto3 optional.
+	@${PROTOC} \
+		--experimental_allow_proto3_optional \
+		--include_imports \
+		--descriptor_set_out=PluginLibDescriptorTestData.bin \
+		-I Protos \
+		${SWIFT_PLUGINLIB_DESCRIPTOR_TEST_PROTOS}
+	@rm -f $@
+	@echo '// See Makefile how this is generated.' >> $@
+	@echo '// swift-format-ignore-file' >> $@
+	@echo 'import Foundation' >> $@
+	@echo 'let fileDescriptorSetBytes: [UInt8] = [' >> $@
+	@xxd -i < PluginLibDescriptorTestData.bin >> $@
+	@echo ']' >> $@
+	@echo 'let fileDescriptorSetData = Data(fileDescriptorSetBytes)' >> $@
+
+Tests/protoc-gen-swiftTests/DescriptorTestData.swift: build ${PROTOC_GEN_SWIFT} ${SWIFT_PLUGIN_DESCRIPTOR_TEST_PROTOS}
 	# Until the flag isn't needed, add the flag to enable proto3 optional.
 	@${PROTOC} \
 		--experimental_allow_proto3_optional \
 		--include_imports \
-		--descriptor_set_out=DescriptorTestData.bin \
+		--descriptor_set_out=PluginDescriptorTestData.bin \
 		-I Protos \
-		${SWIFT_DESCRIPTOR_TEST_PROTOS}
+		${SWIFT_PLUGIN_DESCRIPTOR_TEST_PROTOS}
 	@rm -f $@
 	@echo '// See Makefile how this is generated.' >> $@
 	@echo '// swift-format-ignore-file' >> $@
 	@echo 'import Foundation' >> $@
 	@echo 'let fileDescriptorSetBytes: [UInt8] = [' >> $@
-	@xxd -i < DescriptorTestData.bin >> $@
+	@xxd -i < PluginDescriptorTestData.bin >> $@
 	@echo ']' >> $@
 	@echo 'let fileDescriptorSetData = Data(fileDescriptorSetBytes)' >> $@
 

Package.swift

@@ -69,6 +69,10 @@ let package = Package(
         name: "SwiftProtobufPluginLibraryTests",
         dependencies: ["SwiftProtobufPluginLibrary"]
     ),
+    .testTarget(
+        name: "protoc-gen-swiftTests",
+        dependencies: ["protoc-gen-swift"]
+    ),
   ],
   swiftLanguageVersions: [.v5]
 )

Protos/plugin_descriptor_test.proto

@@ -0,0 +1,63 @@
+// Protos/pluginlib_descriptor_test.proto - test proto
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2017 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
+//
+// -----------------------------------------------------------------------------
+///
+/// Test proto for Tests/SwiftProtobufPluginLibraryTests/Test_Descriptor.swift
+///
+// -----------------------------------------------------------------------------
+
+syntax = "proto2";
+
+package swift_descriptor_test;
+
+// To check handling of extension ranges that are out of order.
+message MsgExtensionRangeOrdering {
+  extensions 1, 3, 2, 4;
+  extensions 7;
+  reserved 8;
+  extensions 9;
+
+  extensions 100 to 110;
+  reserved 121 to 125;
+  extensions 126 to 130;
+  extensions 111 to 120;
+}
+
+// To check handling of extension ranges that are out of order, have fields or
+// reserved things mix through them.
+message MsgExtensionRangeOrderingWithFields {
+  extensions 1, 3, 2, 4;
+  optional int32 field6 = 6;
+  extensions 7;
+  reserved 8;
+  extensions 9;
+
+  extensions 100 to 110;
+  reserved 121 to 123;
+  optional int32 field124 = 124;
+  optional int32 field125 = 125;
+  extensions 126 to 130;
+  extensions 111 to 120;
+  optional int32 field200 = 200;
+}
+
+// Intermixed ranges and fields so help ensure no merge issues
+message MsgExtensionRangeOrderingNoMerging {
+  optional int32 field1 = 1;
+  optional int32 field2 = 2;
+  extensions 3 to 5;
+  optional int32 field6 = 6;
+  extensions 7 to 12;
+  optional int32 field13 = 13;
+  optional int32 field15 = 15;
+  extensions 16 to 20;
+  optional int32 field21 = 21;
+}

Protos/pluginlib_descriptor_test.proto

@@ -106,47 +106,3 @@ message Proto2MessageForPresence {
   }
 
 }
-
-// To check handling of extension ranges that are out of order.
-message MsgExtensionRangeOrdering {
-  extensions 1, 3, 2, 4;
-  extensions 7;
-  reserved 8;
-  extensions 9;
-
-  extensions 100 to 110;
-  reserved 121 to 125;
-  extensions 126 to 130;
-  extensions 111 to 120;
-}
-
-// To check handling of extension ranges that are out of order, have fields or
-// reserved things mix through them.
-message MsgExtensionRangeOrderingWithFields {
-  extensions 1, 3, 2, 4;
-  optional int32 field6 = 6;
-  extensions 7;
-  reserved 8;
-  extensions 9;
-
-  extensions 100 to 110;
-  reserved 121 to 123;
-  optional int32 field124 = 124;
-  optional int32 field125 = 125;
-  extensions 126 to 130;
-  extensions 111 to 120;
-  optional int32 field200 = 200;
-}
-
-// Intermixed ranges and fields so help ensure no merge issues
-message MsgExtensionRangeOrderingNoMerging {
-  optional int32 field1 = 1;
-  optional int32 field2 = 2;
-  extensions 3 to 5;
-  optional int32 field6 = 6;
-  extensions 7 to 12;
-  optional int32 field13 = 13;
-  optional int32 field15 = 15;
-  extensions 16 to 20;
-  optional int32 field21 = 21;
-}