fix(share_plus): Share.shareXFiles resulting in stack-overflow on Windows & Linux

[alexmercerind]

Description

This pull-request fixes an issue where calling Share.shareXFiles caused stack-overflow due to an endless recursion cycle on:

• Windows 10 builds lower than 17763.
• Linux.

Now shareXFiles has been overrided in both ShareLinux & ShareWindows classes, to correctly throw UnimplementedError instead. More information may be located at: #1180 (comment).

NOTE: This fix should be released for both 4.x.x (currently on pub.dev) & 5.x.x (post #1158 i.e. next version).

This pull-request also resolves another issue for older Windows versions (builds lower than 17763), where Dart sided fallback implementation couldn't be registered correctly.

Related Issues

Closes #1180.

Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I titled the PR using Conventional Commits.
• I did not modify the CHANGELOG.md nor the pubspec.yaml files.
• All existing and new tests are passing.
• The analyzer (flutter analyze) does not report any problems on my PR.

Breaking Change

Does your PR require plugin users to manually update their apps to accommodate your change?

• Yes, this is a breaking change (please indicate that with a ! in the title as explained in Conventional Commits).
• No, this is not a breaking change.

[miquelbeltran]

Thanks a lot @alexmercerind

NOTE: This fix should be released for both 4.x.x (currently on pub.dev) & 5.x.x (post #1158 i.e. next version).

I am not sure if this will be possible, so it will just be released with the upcoming major release, unfortunately.

[alexmercerind]

I am not sure if this will be possible, so it will just be released with the upcoming major release, unfortunately.

Understandable. Since, current 4.x.x don't include shareXFiles implementation for Windows/Linux anyway, the error should be understandable to the developers.

[miquelbeltran]

Is shareXFiles implemented on the Windows cpp implementation? I couldn't find it.

[alexmercerind]

Is shareXFiles implemented on the Windows cpp implementation? I couldn't find it.

Yes!

plus_plugins/packages/share_plus/share_plus_windows/windows/share_plus_windows_plugin.cpp

Lines 151 to 152 in 7b6ac7e

	} else if (method_call.method_name().compare(kShareFiles) == 0 ||
	method_call.method_name().compare(kShareFilesWithResult) == 0) {

The platform implementation (MethodChannelShare) for shareXFiles calls shareFilesWithResult internally (see L148 below).
So, same implementation is used on all Windows, Android & iOS.

plus_plugins/packages/share_plus/share_plus_platform_interface/lib/method_channel/method_channel_share.dart

Lines 137 to 155 in 7b6ac7e

	/// Summons the platform's share sheet to share multiple files.
	@override
	Future<ShareResult> shareXFiles(
	List<XFile> files, {
	String? subject,
	String? text,
	Rect? sharePositionOrigin,
	}) {
	final mimeTypes =
	files.map((e) => e.mimeType ?? _mimeTypeForPath(e.path)).toList();
	return shareFilesWithResult(
	files.map((e) => e.path).toList(),
	mimeTypes: mimeTypes,
	subject: subject,
	text: text,
	sharePositionOrigin: sharePositionOrigin,
	);
	}

[miquelbeltran]

Got it, thanks!