Modifying of the Mwe2 workflow generated by Xtext programmatically

Question

I'm running Mwe2 workflow programmatically and I need to add referencedResource for the Terminals.xtext to the GenerateYourDsl.mwe2 file in order to run this workflow successfully. Mentioned GenerateYourDsl.mwe2 file is generated by Xtext when I create new project - I didn't modify it. Is it somehow possible to get object out of this workflow, access it in Java and add this one attribute to the language attribute of the component attribute of the workflow ?

Here's the workflow:

Workflow {

    component = XtextGenerator {
        configuration = {
            project = StandardProjectConfig {
                baseName = "org.example.yourdsl"
                rootPath = rootPath
                eclipsePlugin = {
                    enabled = true
                }
                createEclipseMetaData = true
            }
            code = {
                encoding = "UTF-8"
                lineDelimiter = "\n"
                fileHeader = "/*\n * generated by Xtext \${version}\n */"
            }
        }
        language = StandardLanguage {
            name = "org.example.yourdsl.YourDsl"
            fileExtensions = "yourdsl"
            //following line needs to be added - in original generated workflow it is not
           referencedResource = "platform:/resource/org.eclipse.xtext/org/eclipse/xtext/common/Terminals.xtext"

            serializer = {
                generateStub = false
            }
            validator = {
                // composedCheck = "org.eclipse.xtext.validation.NamesAreUniqueValidator"
                // Generates checks for @Deprecated grammar annotations, an IssueProvider and a corresponding PropertyPage
                generateDeprecationValidation = true
            }
        }
    }
}

I'm generating projects programmatically (using CliProjectsCreator and WizardConfiguration) and need to run the workflow when the projects are generated in order to generate src, src-gen files etc. But as I'm trying to run it programmatically (not in Eclipse) and Terminals are used in my grammar, I'm getting this error:

XtextLinkingDiagnostic: null:1 Couldn't resolve reference to Grammar 'org.eclipse.xtext.common.Terminals'.
TransformationDiagnostic: null:36 Cannot create datatype WS. If this is supposed to return EString, make sure you have imported 'http://www.eclipse.org/emf/2002/Ecore' (ErrorCode: NoSuchTypeAvailable)
TransformationDiagnostic: null:39 Cannot create datatype NAME_TERMINAL. If this is supposed to return EString, make sure you have imported 'http://www.eclipse.org/emf/2002/Ecore' (ErrorCode: NoSuchTypeAvailable)
TransformationDiagnostic: null:42 Cannot create datatype VALUE_TERMINAL. If this is supposed to return EString, make sure you have imported 'http://www.eclipse.org/emf/2002/Ecore' (ErrorCode: NoSuchTypeAvailable)

why do you want to do that? terminals.xtext is available implicitely — Christian Dietrich
It's not available implicitly when you're running the workflow programmatically - not in Eclipse. — scanyboss
can you give more details? maybe you do something strange classpath wise — Christian Dietrich
you should debug org.eclipse.xtext.xtext.XtextLinkingService.getUsedGrammar(Grammar, INode) org.eclipse.xtext.resource.ClassloaderClasspathUriResolver.resolve(Object, URI) what do you mean by "run programatically" — Christian Dietrich

Christian Dietrich Christian Dietrich · Accepted Answer · 2019-03-11T06:42:56

there should be no need to add the terminals grammar explicitely. It should be found on the classpath via org.eclipse.xtext.resource.ClassloaderClasspathUriResolver.resolve(Object, URI) if the workflow is called with a proper classpath. have a look what the wizard creates when selecting maven: a call to the maven exec plugin calling into Mwe2Launcher main with the proper classpath

Modifying of the Mwe2 workflow generated by Xtext programmatically

1 Answers