Fix errors when compiling with Swift file on iOS lower than 14

[maksg]

Details

If a Swift file was added to the project with podspec target set to iOS 13 and lower, the app wouldn't compile and would throw file not found errors.

[tomekzaw]

@staszekscp Could you please check if this change works correctly with static/dynamic linking in the hybrid app?

[j-piasecki]

I assume you've checked, but just to make sure: this doesn't break the new arch build, right?

[tomekzaw]

• NO_FLIPPER=1 USE_FRAMEWORKS=static pod install ✅
• NO_FLIPPER=1 USE_FRAMEWORKS=static RCT_NEW_ARCH_ENABLED=1 pod install ✅
• NO_FLIPPER=1 USE_FRAMEWORKS=dynamic pod install 🔴

ld: Undefined symbols:
  _OBJC_CLASS_$_RCTBackedTextFieldDelegateAdapter, referenced from:
      __OBJC_$_CATEGORY_RCTBackedTextFieldDelegateAdapter_$_Markdown in RCTBackedTextFieldDelegateAdapter+Markdown.o
  _OBJC_CLASS_$_RCTBaseTextInputView, referenced from:
       in MarkdownTextInputDecoratorView.o
      __OBJC_$_CATEGORY_RCTBaseTextInputView_$_Markdown in RCTBaseTextInputView+Markdown.o
  _OBJC_CLASS_$_RCTUITextField, referenced from:
       in MarkdownTextInputDecoratorView.o
  _OBJC_CLASS_$_RCTUITextView, referenced from:
       in MarkdownTextInputDecoratorView.o
      l_OBJC_CLASSLIST_SUP_REFS_$_ in RCTUITextView+Markdown.o
      __OBJC_$_CATEGORY_RCTUITextView_$_Markdown in RCTUITextView+Markdown.o
clang: error: linker command failed with exit code 1 (use -v to see invocation)

• NO_FLIPPER=1 USE_FRAMEWORKS=dynamic RCT_NEW_ARCH_ENABLED=1 pod install 🔴

ld: Undefined symbols:
  _OBJC_CLASS_$_RCTBackedTextFieldDelegateAdapter, referenced from:
      __OBJC_$_CATEGORY_RCTBackedTextFieldDelegateAdapter_$_Markdown in RCTBackedTextFieldDelegateAdapter+Markdown.o
  _OBJC_CLASS_$_RCTBaseTextInputView, referenced from:
      __OBJC_$_CATEGORY_RCTBaseTextInputView_$_Markdown in RCTBaseTextInputView+Markdown.o
  _OBJC_CLASS_$_RCTUITextField, referenced from:
       in MarkdownTextInputDecoratorView.o
  _OBJC_CLASS_$_RCTUITextView, referenced from:
       in MarkdownTextInputDecoratorView.o
      l_OBJC_CLASSLIST_SUP_REFS_$_ in RCTUITextView+Markdown.o
      __OBJC_$_CATEGORY_RCTUITextView_$_Markdown in RCTUITextView+Markdown.o
clang: error: linker command failed with exit code 1 (use -v to see invocation)

[tomekzaw]

Looks like USE_FRAMEWORKS=dynamic also does not work on current main (cd42c45). Reported as #321.

[tomekzaw]

Thanks for this PR! @staszekscp confirms it works for him as well.