When add_schematic_component is called with a schematic that lives in a
sub-folder (e.g. sheets/rs485.kicad_sch), the handler derived the project
path as schematic.parent — which in a hierarchical project is the sheets/
directory, not the project root. Any project-local symbol library declared
in sym-lib-table (using ${KIPRJMOD}) is invisible to DynamicSymbolLoader
from that directory, causing "Symbol 'X' not found in library 'Y'" even
though the library file and sym-lib-table entry both exist.
Fix: walk the ancestor chain from the schematic file upward until a
directory is found that contains a sym-lib-table file or a .kicad_pro
file, then use that as the project root for library resolution.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
6578667197