import * as fse from "fs-extra" ; import { PathLike } from "fs-extra" ; const CONTROL_INSERT_START_ID = "←" ; const CONTROL_INSERT_END_ID = "|" ; /**
 * Attemps to inherit a .yy json file with a parent and child file
 */ export async function inheritYYFile ( childPath , parentPath , outputPath ) { type IChangeList = Array < { id : string ; changes : { [ key ] : any ; } ; } > ; const parent = JSON . parse ( ( await fse . readFileSync ( parentPath ) ) . toString ( ) ) ; const inherited = ( await fse . readFileSync ( childPath ) ) . toString ( ) ; let insId = "" ; let insContent = "" ; let insState = "SEEK" ; const changes = [ ] ; for ( let i = 0 ; i < inherited . length ; i ++ ) { let char = inherited . charAt ( i ) ; switch ( insState ) { case "SEEK" : insId = "" ; insContent = "" ; if ( char === CONTROL_INSERT_START_ID ) { insState = "READ_ID" ; } break ; case "READ_ID" : if ( char !== CONTROL_INSERT_END_ID ) { insId += char ; if ( char === CONTROL_INSERT_START_ID ) { insId = "" ; insContent = "" ; } } else { insState = "none" ; let brackedCount = 1 ; i += 2 ; while ( brackedCount !== 0 ) { char = inherited . charAt ( i ) ; insContent += char ; if ( char === "{" ) { brackedCount ++ ; } else if ( char === "}" ) { brackedCount -- ; } i ++ ; } i -= 2 ; insState = "SEEK" ; changes . push ( { id : insId , changes : JSON . parse ( "{" + insContent ) } ) ; } break ; } } const combine = ( object , changeList ) => { for ( const attributename in object ) { if ( attributename in object ) { const item = object [ attributename ] ; if ( typeof item === "object" ) { object [ attributename ] = combine ( item , changeList ) ; } } } if ( object ) { for ( const change of changeList ) { if ( object . id === change . id ) { Object . assign ( object , change . changes ) ; } } } return object ; } ; await fse . writeFile ( outputPath as any , JSON . stringify ( combine ( parent , changes ) , undefined , 2 ) ) ; }