What: each property row that can take an expression (it has a stopwatch) now
has a property pick whip in the Parent & Link column, as in After Effects
CC 2018 and later (automation id `timeline.prop.<uid>.propertyPickWhip`).
Dragged onto another property's name or one of its values, it runs
`prop.pickWhip`: the reference is added as the property's expression, or
replaces the one it has, and the expression is enabled. A drop on one value
picks that dimension (`position[1]`).
The parent, expression and property pick whips share one widget and one
drop path (rubber band, autoscroll, dimension pick); only the expression
pick whip inserts at the cursor of an expression being edited.
Pick whips (expression and property) now also drop on properties in
Effect Controls: its property rows register as targets while a pick whip
is dragged, with their per-dimension value fields.
Why: the last part of #363. Adobe's docs say the Property Link pick whip
adds the expression without enabling expressions first, and a pick whip
outside an edit replaces the whole expression text. No modifier keys for
the property pick whip are documented, so none are implemented.
Tests: `the_property_pick_whip_links_a_property_to_another` (ui_inline_edit)
drops it on a property's name, on one of Position's values, on a property
with a disabled expression (replaced and enabled), on an Effect Controls
slider and one value of a point, and on itself (no change). It fails
before the change; with Effect Controls' targets removed it fails at the
slider. Looked at the result with the headless snapshot.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
67b9b20a07