Looks like specified template was not found by code generation process.
You've used xpt::propsheet::PropertySource::Class template for GenDiagram
input.
This means there should be xpt/propsheet/PropertySource.xpt file with appropriate
definition in one of the template roots.
By default GMF generator load all the templates from GMF plugins (you probably
can not add your template there) + customized templates from the "template
directory" (specified by corresponding property of GenEditorGenerator) if
GenEditorGenerator.Dynamic template property was set to true.
So, can you please check that:
- GenEditorGenerator.template directory = "/<projectName>/<templateDirectoryName>"
- GenEditorGenerator.dynamic template = "true"
- xpt/propsheet/PropertySource.xpt is available in /<projectName>/<templateDirectoryName>
folder.
- there is corresponding definition inside this template file.