Marketing: Do not show "Create a campaign" button if there are no campaign types

[ecgan]

Submission Review Guidelines:

• I have followed the WooCommerce Contributing Guidelines and the WordPress Coding Standards.
• I have checked to ensure there aren't other open Pull Requests for the same update/change.
• I have reviewed my code for security best practices.
• Following the above guidelines will result in quick merges and clear and detailed feedback when appropriate.

Changes proposed in this Pull Request:

Closes #38805.

In this PR, we add conditions for rendering the "Create a campaign" button in the Introduction Banner card:

• When there are no supported campaign types, the "Create a campaign" button and "Add channels" button will not be displayed (note that when there are no campaign types, the "Campaigns" card will not be displayed too):

• When there are supported campaign types, the "Create a campaign" button will be displayed (the "Campaigns" card is displayed here, with a "Create new campaign" button in the card header):

I also added code for the "Create new campaign" button in the "Campaigns" card, so that "Create new campaign" button will not be shown when there are no campaign types. See the example screenshot below. Note that currently the "Campaigns" card is not displayed when there are no campaign types; this is because there is no match between the supported campaign types and the campaign types in the marketing campaigns, and the GET /marketing/campaigns API call returns an error instead of campaigns data. The code added is for "future proofing" just in case.

How to test the changes in this Pull Request:

Using the WooCommerce Testing Instructions Guide, include your detailed testing instructions:

Note: to test the changes, you may need to use some test data in some marketing channel extension. The following is an example of how to do that using Google Listings and Ads:

1. Enable multichannel marketing for Google Listings and Ads using the following script:

add_filter( 'woocommerce_gla_enable_mcm', function( $enabled ) {
	return true;
});

2. Modify the get_campaigns function in https://github.com/woocommerce/google-listings-and-ads/blob/33243ae88cf0b930d9956903738ececb5069a11e/src/MultichannelMarketing/GLAChannel.php#LL178C42-L178C42, so that it returns some sample marketing campaigns:

	public function get_campaigns(): array {
		return [
			new MarketingCampaign(
				'1',
				$this->campaign_types['google-ads'],
				'Test campaign',
				admin_url( 'admin.php?page=wc-admin&path=/google/settings&subpath=/campaigns/edit' ),
				new Price( '100', 'USD' ),
			),
			new MarketingCampaign(
				'2',
				$this->campaign_types['google-ads'],
				'Test campaign 2',
				admin_url( 'admin.php?page=wc-admin&path=/google/settings&subpath=/campaigns/edit' ),
				new Price( '100', 'USD' ),
			),
		];
	}

3. Modify the generate_campaign_types function in https://github.com/woocommerce/google-listings-and-ads/blob/33243ae88cf0b930d9956903738ececb5069a11e/src/MultichannelMarketing/GLAChannel.php#L213-L224, so that it returns empty array for campaign types:

	protected function generate_campaign_types(): array {
		return [];
	}

Test Steps:

1. Go to the WooCommerce > Marketing page: /wp-admin/admin.php?page=wc-admin&path=%2Fmarketing
2. Without modifying generate_campaign_types, you should see "Create a campaign" button in the introduction banner, and you should see "Create a campaign" button in the "Campaigns" card.
3. Modify the generate_campaign_types function to return empty array. You should NOT see "Create a campaign" button in the introduction banner. The "Campaigns" card should not be shown. In the browser network panel, you should see an error for the GET /marketing/campaigns API call.

[github-actions]

Hi , @woocommerce/ventures, @woocommerce/automata

Apart from reviewing the code changes, please make sure to review the testing instructions as well.

You can follow this guide to find out what good testing instructions should look like:
https://github.com/woocommerce/woocommerce/wiki/Writing-high-quality-testing-instructions

[github-actions]

Hi , @woocommerce/ventures, @woocommerce/automata

Apart from reviewing the code changes, please make sure to review the testing instructions as well.

You can follow this guide to find out what good testing instructions should look like:
https://github.com/woocommerce/woocommerce/wiki/Writing-high-quality-testing-instructions

[github-actions]

Test Results Summary

Commit SHA: 04294c4

Test 🧪	Passed ✅	Failed 🚨	Broken 🚧	Skipped ⏭️	Unknown ❔	Total 📊	Duration ⏱️
API Tests	259	0	0	2	0	261	1m 0s
E2E Tests	190	0	0	18	0	208	14m 16s

---

To view the full API test report, click here.
To view the full E2E test report, click here.
To view all test reports, visit the WooCommerce Test Reports Dashboard.

[budzanowski]

Looks good. I have left one comment for the comment copy and one comment for the logic. It works if you disregard the comment so it is up to you if you want to use it. Either way approving. Nice change!