Port most of the viewer's end-to-end tests here

[skjnldsv]

The Playwright specs stayed in nextcloud/server when the viewer moved out. That was right for the move itself, but most of them are not really about the server.

Of the 47 specs, the ones that genuinely test integration should stay there: opening from the Files list, public link shares, the sidebar, and the browser history and URL behaviour. Those exercise wiring this repository cannot see, and they are the sanity check that the package a server ships actually works inside it.

The rest — navigation between files, odd file names, per-format media playback, error handling, the compare API, the editor action, the accessibility pass — are about the viewer itself and would run faster and closer to the code here.

That needs a browser test setup in this repository: a playground page mounting the viewer over some fixture files, and Playwright wired to it, roughly as nextcloud-image-editor does.

One thing to settle first, and the reason this is not a mechanical move: the viewer talks to WebDAV and to the previews endpoint, and a playground has neither. Either the fixtures are File nodes whose source is a plain URL served by the dev server, if the viewer copes with a node that is not DAV-backed, or the playground stubs those requests. The first would also give this repository a working demo page for the docs to link to.

• Decide whether a non-DAV File node is enough to drive the viewer
• Playground page and Playwright setup
• Port the specs that are about the viewer
• Leave the integration specs in the server, and say so in both repos

[skjnldsv]

The blocking question is answered: a File node that is not DAV-backed drives the viewer fine.

NodeData.source documents a plain URL as valid (or https://domain.com/Photos/picture.jpg), and with hasPreview left off, getPreviewIfAny() returns file.source and Images.vue loads it directly instead of asking a previews endpoint. The rest of what the viewer reaches for is already guarded: loadState has a default, the Files router is optional, and the public-share helpers are only called for files that do have a preview. The one requirement is root, which must be a real prefix of the source path — an empty one throws Missing mandatory root.

So the playground is in, serving its fixtures from the dev server with no Nextcloud behind it, and it doubles as the demo page the docs link to.

• Decide whether a non-DAV File node is enough to drive the viewer
• Playground page and Playwright setup
• Port the specs that are about the viewer
• Leave the integration specs in the server, and say so in both repos

Navigation moved across first, plus one new spec pinning down that paging follows the handler group and not the whole list — video and audio share media, images have no group, so an image list stops at the images. That behaviour had no test either side.

Still to move: odd file names, per-format media playback, error handling, the compare API, the editor action, the accessibility pass. Staying in the server: the Files list, public shares, the sidebar, and the history and URL behaviour.