id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
22634	[PATCH] Sorting relation members by connectivity changes order multiple times	skorbut	team	"While working with the relation editor, I noticed the following unexpected behaviour: If I use the function ""Sort the relation members"" multiple times, the order of elements changes the first few times, until it finally converges.

==== What steps will reproduce the problem?

You can see and reproduce the behaviour with the attached file: Open the file, select all ways, in the relation window click the + button (""Create a new relation""). Add the selection to the members list, then click ""Sort the relation members"" multiple times.


==== What is the expected result?

The order of objects should stay the same after the first sorting.

==== What happens instead?

The order of objects changes a few times before staying the same.


==== Please provide any additional information below. Attach a screenshot if possible.

I wrote a small patch that sorts the ways by hashcode before doing the actual sorting. Sorting by way id or similar might be possible but would not provide any advantage AFAICS: The purpose is only to make the order of the objects the same for each call of `sortMembersByConnectivity`.

I also noticed that the sort function does not return a sequence with the minimum possible number of discontinuities. I plan to address that in another ticket.



{{{
Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2022-12-05 23:37:01 +0100 (Mon, 05 Dec 2022)
Revision:18608
Build-Date:2022-12-06 02:30:56
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (18608 en) Linux Ubuntu 18.04.6 LTS
Memory Usage: 618 MB / 7976 MB (239 MB allocated, but free)
Java version: 11.0.17+8-post-Ubuntu-1ubuntu218.04, Ubuntu, OpenJDK 64-Bit Server VM
Look and Feel: javax.swing.plaf.metal.MetalLookAndFeel
Screen: :0.0 2560×1440 (scaling 1.00×1.00) :0.1 2560×1440 (scaling 1.00×1.00) :0.2 1050×1680 (scaling 1.00×1.00)
Maximum Screen Size: 2560×1680
Best cursor sizes: 16×16→16×16, 32×32→32×32
Environment variable LANG: en_US.UTF-8
System property file.encoding: UTF-8
System property sun.jnu.encoding: UTF-8
Locale info: en_US
Numbers with default locale: 1234567890 -> 1234567890
Desktop environment: MATE
Java package: openjdk-11-jre:amd64-11.0.17+8-1ubuntu2~18.04
Java ATK Wrapper package: libatk-wrapper-java:all-0.33.3-20ubuntu0.1
libcommons-compress-java: libcommons-compress-java:all-1.18-1~18.04
libcommons-logging-java: libcommons-logging-java:all-1.2-2
fonts-noto: fonts-noto:all-20171026-2
VM arguments: [--module-path=/usr/share/openjfx/lib, --add-modules=java.scripting,java.sql,javafx.controls,javafx.media,javafx.swing,javafx.web, -Djosm.restart=true, -Djosm.dir.name=JOSM-latest, -Djava.net.useSystemProxies=true, --add-exports=java.base/sun.security.action=ALL-UNNAMED, --add-exports=java.desktop/com.sun.imageio.plugins.jpeg=ALL-UNNAMED, --add-exports=java.desktop/com.sun.imageio.spi=ALL-UNNAMED]

Plugins:
+ KartaView (408)
+ Mapillary (2.0.2)
+ OpeningHoursEditor (35924)
+ apache-commons (36034)
+ apache-http (35924)
+ jna (36005)
+ measurement (35978)
+ pbf (36034)
+ todo (30306)

Map paint styles:
+ https://josm.openstreetmap.de/josmfile?page=Styles/Coloured_Streets&zip=1

Last errors/warnings:
- 00015.148 E: java.lang.NumberFormatException: For input string: ""test""
- 00015.343 W: Cannot start IPv4 remotecontrol server on port 8111: Address already in use (Bind failed)
- 00015.344 W: Cannot start IPv6 remotecontrol server on port 8111: Address already in use (Bind failed)
}}}
"	enhancement	new	normal		Core			template_report