Don't require objc in modulemaps generated for Swift compatibility headers

xymus · xymus · commit 01a7c3d87b23 · 2025-06-26T13:43:55.000-07:00
Let's remove the `requires objc` from the module map file generated for
the compatibility header. This condition triggered an error when
importing the compatibility header from a C source file.

This declaration is superfluous, the compatibility header is already
printed in a way where the Objective-C code is protected behind a
language check. C clients can safely import the current compatibility
header even if they may not see any content.

Let's lift this restriction. It isn't currently necessary and we're
adding C content to the compatibility header with the official support
for `@cdecl` that is independent of Objective-C.
diff --git a/Sources/SWBTaskConstruction/TaskProducers/OtherTaskProducers/ModuleMapTaskProducer.swift b/Sources/SWBTaskConstruction/TaskProducers/OtherTaskProducers/ModuleMapTaskProducer.swift
@@ -404,7 +404,6 @@ final class ModuleMapTaskProducer: PhasedTaskProducer, TaskProducer {
                 outputStream <<< "module \(try moduleName.asModuleIdentifierString()).Swift {\n"
             }
             outputStream <<< "  header \"\(interfaceHeaderName.asCStringLiteralContent)\"\n"
-            outputStream <<< "  requires objc\n"
             outputStream <<< "}\n"
 
             return outputStream.bytes
diff --git a/Tests/SWBTaskConstructionTests/ModuleMapTaskConstructionTests.swift b/Tests/SWBTaskConstructionTests/ModuleMapTaskConstructionTests.swift
@@ -584,7 +584,6 @@ fileprivate struct ModuleMapTaskConstructionTests: CoreBasedTests {
                     #expect(contents == (OutputByteStream()
                                          <<< "framework module SwiftOnly {\n"
                                          <<< "  header \"SwiftOnly-Swift.h\"\n"
-                                         <<< "  requires objc\n"
                                          <<< "}\n").bytes)
                 }
 
@@ -629,7 +628,6 @@ fileprivate struct ModuleMapTaskConstructionTests: CoreBasedTests {
                                          <<< "\n"
                                          <<< "module ObjCCompatibilityHeader.Swift {\n"
                                          <<< "  header \"ObjCCompatibilityHeader-Swift.h\"\n"
-                                         <<< "  requires objc\n"
                                          <<< "}\n").bytes)
                 }
 
@@ -978,7 +976,6 @@ fileprivate struct ModuleMapTaskConstructionTests: CoreBasedTests {
                                                      <<< "\n"
                                                      <<< "module \(targetName).Swift {\n"
                                                      <<< "  header \"\(targetName)-Swift.h\"\n"
-                                                     <<< "  requires objc\n"
                                                      <<< "}\n").bytes)
                             }
 
diff --git a/Tests/SWBTaskConstructionTests/SwiftTaskConstructionTests.swift b/Tests/SWBTaskConstructionTests/SwiftTaskConstructionTests.swift
@@ -606,7 +606,6 @@ fileprivate struct SwiftTaskConstructionTests: CoreBasedTests {
                 #expect(contents == (OutputByteStream()
                                      <<< "framework module CoreFoo {\n"
                                      <<< "  header \"CoreFoo-Swift.h\"\n"
-                                     <<< "  requires objc\n"
                                      <<< "}\n").bytes)
             }
         }
@@ -1086,7 +1085,6 @@ fileprivate struct SwiftTaskConstructionTests: CoreBasedTests {
                     stream <<< "\n"
                     stream <<< "module CoreFoo.Swift {\n"
                     stream <<< "  header \"CoreFoo-Swift.h\"\n"
-                    stream <<< "  requires objc\n"
                     stream <<< "}\n"
                     #expect(contents == stream.bytes)
 

Original file line number	Diff line number	Diff line change
`@@ -404,7 +404,6 @@ final class ModuleMapTaskProducer: PhasedTaskProducer, TaskProducer {`
`404`	`404`	`outputStream <<< "module \(try moduleName.asModuleIdentifierString()).Swift {\n"`
`405`	`405`	`}`
`406`	`406`	`outputStream <<< " header \"\(interfaceHeaderName.asCStringLiteralContent)\"\n"`
`407`		`- outputStream <<< " requires objc\n"`
`408`	`407`	`outputStream <<< "}\n"`
`409`	`408`
`410`	`409`	`return outputStream.bytes`
Original file line number	Diff line number	Diff line change
`@@ -584,7 +584,6 @@ fileprivate struct ModuleMapTaskConstructionTests: CoreBasedTests {`
`584`	`584`	`#expect(contents == (OutputByteStream()`
`585`	`585`	`<<< "framework module SwiftOnly {\n"`
`586`	`586`	`<<< " header \"SwiftOnly-Swift.h\"\n"`
`587`		`- <<< " requires objc\n"`
`588`	`587`	`<<< "}\n").bytes)`
`589`	`588`	`}`
`590`	`589`
`@@ -629,7 +628,6 @@ fileprivate struct ModuleMapTaskConstructionTests: CoreBasedTests {`
`629`	`628`	`<<< "\n"`
`630`	`629`	`<<< "module ObjCCompatibilityHeader.Swift {\n"`
`631`	`630`	`<<< " header \"ObjCCompatibilityHeader-Swift.h\"\n"`
`632`		`- <<< " requires objc\n"`
`633`	`631`	`<<< "}\n").bytes)`
`634`	`632`	`}`
`635`	`633`
`@@ -978,7 +976,6 @@ fileprivate struct ModuleMapTaskConstructionTests: CoreBasedTests {`
`978`	`976`	`<<< "\n"`
`979`	`977`	`<<< "module \(targetName).Swift {\n"`
`980`	`978`	`<<< " header \"\(targetName)-Swift.h\"\n"`
`981`		`- <<< " requires objc\n"`
`982`	`979`	`<<< "}\n").bytes)`
`983`	`980`	`}`
`984`	`981`
Original file line number	Diff line number	Diff line change
`@@ -606,7 +606,6 @@ fileprivate struct SwiftTaskConstructionTests: CoreBasedTests {`
`606`	`606`	`#expect(contents == (OutputByteStream()`
`607`	`607`	`<<< "framework module CoreFoo {\n"`
`608`	`608`	`<<< " header \"CoreFoo-Swift.h\"\n"`
`609`		`- <<< " requires objc\n"`
`610`	`609`	`<<< "}\n").bytes)`
`611`	`610`	`}`
`612`	`611`	`}`
`@@ -1086,7 +1085,6 @@ fileprivate struct SwiftTaskConstructionTests: CoreBasedTests {`
`1086`	`1085`	`stream <<< "\n"`
`1087`	`1086`	`stream <<< "module CoreFoo.Swift {\n"`
`1088`	`1087`	`stream <<< " header \"CoreFoo-Swift.h\"\n"`
`1089`		`- stream <<< " requires objc\n"`
`1090`	`1088`	`stream <<< "}\n"`
`1091`	`1089`	`#expect(contents == stream.bytes)`
`1092`	`1090`