Friend of mine got the same XML error, anyone got any ideas to possible reasons?

I also got this error :(
I think it has to do with `<affordances><li>Marsh</li></affordances><affordances><li>VFEM_Moatable</li></affordances>`
The "VFEM_Moatable" must come from this mod, but I don't know what is putting "Marsh"

found a solution that works for me: change the order that "Vanilla Factions Expanded - Medieval" and "ReGrowth: Core and Framework" load in

Tl;dr : Read the section below the ======= signs, and follow those steps for your copy, to remove this error.

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I receive the same errors, and do not have ReGrowth anything installed.

If I remove VFEM (Medieval), it goes away and no errors at all in the debug.

I was fairly certain it's caused by AddTerrainAffordance.xml (in 1.3/patches/) and MoatableTerrain.xml (in 1.3/defs/TerrainListDef/) both referencing "WaterShallow" and "Marsh".

To test this, I removed the references to both of them in MoatableTerrain.xml - but that did not fix it.

I then looked into AddTerrainAffordance, and noticed these two lines:

<Operation Class="PatchOperationAdd">
<xpath>/Defs/TerrainDef[defName="SoftSand" or defName="Sand" or defName="Soil" or defName="Gravel" or defName="MossyTerrain" or defName="MarshyTerrain"]/affordances</xpath>

Then, I noticed:

<Operation Class="PatchOperationAdd">
<xpath>/Defs/TerrainDef[defName="Marsh" or defName="WaterShallow"]</xpath>

In the first, containing defs that do NOT pop this error, I notice the bracket with the conditionals in it is followed by /affordances - but in the two defs that DO pop this error, no /affordances.

I tested my theory by removing the PatchOperationAdd operation and its children, saving a copy, and launching.

It launched with no errors.

I then tested by re-adding the code, but making the behavior match the first patchoperationadd almost exactly...

And it launches with no errors.

Finally, I tested by making the top line:

<xpath>/Defs/TerrainDef[defName="SoftSand" or defName="Sand" or defName="Soil" or defName="Gravel" or defName="MossyTerrain" or defName="MarshyTerrain" or defName="Marsh" or defName="WaterShallow"]/affordances</xpath>

So it takes those two entries in the same patch operation add.

Once again, tested - no errors.

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Conclusion:
The issue is caused by 1.3\Patches\AddTerrainAffordance.xml having malformed code that patches two terrain defs, Marsh, and WaterShallow, to add the Affordance "VFEM_Moatable".

When this file is processed, it properly patches the other terrain defs referenced in the file, but these two are handled and worded differently in code. As a result, when the system tries to add a SECOND <affordances> XML node, that's when the XML parser throws an error that there is a duplicate <affordances> XML node.

The way the first operation works, it finds the existing <affordances> node, and adds the contents to it properly.



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Oskar, please modify 1.3\Patches\AddTerrainAffordance.xml to the following:


<?xml version="1.0" encoding="utf-8"?>
<Patch>
<Operation Class="PatchOperationAdd">
<xpath>/Defs/TerrainDef[defName="SoftSand" or defName="Sand" or defName="Soil" or defName="Gravel" or defName="MossyTerrain" or defName="MarshyTerrain" or defName="Marsh" or defName="WaterShallow"]/affordances</xpath>
<value>
<li>VFEM_Moatable</li>
</value>
</Operation>
</Patch>


This should make VFEM properly 1.3 compliant without giving XML errors.

Thank you to Gedrean, that fix worked for me. Hopefully it gets incorporated into a future official update.