[2.0.73] editor's instant building sometimes only places elevated signal ghosts

[sben]

when using instant building in the editor, all entities should be placed immediately, with no ghost intermediates.

This does not happen always for elevated rail signals;
see the video below:

- i got elevated rail signal ghosts, i am not sure how but this should not have happened

- copying and placing in place should build them, this works for elevated chain signals but not normal signals (the chain signals were intentional ghosts for demonstration purposes)

- when placing the clipboard contents at a new location, the rail signals get successfully built but this time the rail chain signals get only placed as ghosts

blueprint:

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Copy blueprint

[sben]

possibly related, possibly different bug - but also cannot place rail signals alongside this rail segment, failing due to different reasons, either:

• signals must be built next to rails
• invalid signal position

[Rseding91]

Thanks for the report however everything here is working correctly. The signals in the first video are simply invalid: you've made a set of rails that can't be passed either way because they aren't by-directional. The instant-build logic detects the invalid-signal and refuses to revive the ghost.

If you attempt to send any train through that piece of rail with all signals built it will never work.