[FIX] Theme Build: Only process themes within library namespace

[matz3]

Themes are expected to be within a "themes" folder directly below the
library namespace.
Other "themes" folders (e.g. within sub-directories) should be ignored
and not compiled/processed.

[coveralls]

Coverage decreased (-0.008%) to 93.678% when pulling 9267ddc on fix-themes-glob-patterns into 08a34ae on master.

[RandomByte]

Do we deem this to be compatible because the runtime never loads themes from other paths anyways? Can't an application still load CSS from other paths?

What's the issue we are fixing here?

[RandomByte]

Apparently the namespace can be undefined here, see:

ui5-builder/lib/types/library/LibraryBuilder.js

Lines 6 to 11 in 08a34ae

	if (!project.metadata.namespace) {
	// TODO 3.0: Throw here
	log.info("Skipping some tasks due to missing library namespace information. Your project " +
	"might be missing a manifest.json or .library file. " +
	"Also see: https://sap.github.io/ui5-tooling/pages/Builder/#library");
	}

So a check and fallback is needed.

Do we need the same change in ThemeLibraryBuilder.js?

[matz3]

For theme-library I decided to rather stay with the existing pattern as we don't really know the namespaces. One solution would be to filter using the information of the available libraries, but that would be a bit more complex and requires that knowledge also within the generateThemeDesignerResources task.
I think for theme-libraries we can expect that it only contains themes folders that should be compiled.

[RandomByte]

Ok, makes sense! However, we still to add a check for the namespace here, otherwise you might end up with /resources/undefined/themes/*/library.source.less here

[matz3]

Done

[codeworrior]

Do we deem this to be compatible because the runtime never loads themes from other paths anyways? Can't an application still load CSS from other paths?

What's the issue we are fixing here?

Yes, the missing runtime support is what makes us consider this as compatible. Libraries don't load themes from a location other than their namespace.

And the issue that we fix here is the unwanted (and sometimes broken) automatic triggering of a theme build just by the naming of a folder. The only convention for libraries is that their root namespace can contain a themes folder whose child folders contain the individual themes. And those will be built. See https://github.com/SAP/openui5/blob/master/docs/controllibraries.md#file-structure .