Skip podspec Swift Search Path validation if only swift file is Package.swift

[vashworth]

Usually when an iOS plugin uses Swift files, it requires a workaround in the podspec to add Swift to the search paths. Part of the podspec-check command is validating this workaround is found. However, when the only Swift file is the Package.swift (Swift Package Manager manifest), skip this validation since having this file does not indicate the plugin uses Swift files.

Fixes flutter/flutter#147548.

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the relevant style guides and ran the auto-formatter. (Unlike the flutter/flutter repo, the flutter/packages repo does use dart format.)
• I signed the CLA.
• The title of the PR starts with the name of the package surrounded by square brackets, e.g. [shared_preferences]
• I linked to at least one issue that this PR fixes in the description above.
• I updated pubspec.yaml with an appropriate new version according to the pub versioning philosophy, or this PR is exempt from version changes.
• I updated CHANGELOG.md to add a description of the change, following repository CHANGELOG style.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel on Discord.

[stuartmorgan]

Also, skip license check for Package.swift files.

I don't think we should skip the license here; it's authored code, not generated code. Even though it's not very interesting, it's still non-generated.

[vashworth]

Also, skip license check for Package.swift files.

I don't think we should skip the license here; it's authored code, not generated code. Even though it's not very interesting, it's still non-generated.

I was thinking it didn't need to be licensed since we don't license the podspec file. Also, Package.swift is very picky about what comments are at the top of the file. The first comment has to be the tools version.

So to license it, it would look like

// swift-tools-version: 5.9

// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import PackageDescription

let package = Package(
...

Is that okay?

[stuartmorgan]

That should be fine; it's similar to how bash script files have a #! comment before the license block section since that also has to be the very first line.

[stuartmorgan]

LGTM