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Bug 362581

Summary:

[serializer] Syntactic sequencer extension for serialization of optional keywords doesn't work

Product:

[Modeling] TMF

Reporter:

Miro Spoenemann <msp>

Component:

Xtext

Assignee:

Project Inbox <tmf.xtext-inbox>

Status:

CLOSED FIXED

QA Contact:

Severity:

normal

Priority:

CC:

moritz.eysholdt, sven.efftinge

Version:

2.1.0

Flags:

sven.efftinge: juno+

Target Milestone:

Hardware:

OS:

Linux

Whiteboard:

Attachments:

Description	Flags
Syntactic sequencer for the example grammar	none
Command handler that serializes a model to demonstrate the problem	none

Description Miro Spoenemann

2011-11-01 13:39:46 EDT

Build Identifier: 20110916-0149

For a grammar with optional keywords such as

Model:     greetings+=Greeting*;
Greeting:  'Hello' name=ID '!'?;

the new serializer generates a class AbstractMyDslSyntacticSequencer with an init(IGrammarAccess) method that creates this matching rule:

match_Greeting_ExclamationMarkKeyword_2_q = new TokenAlias(true, false, grammarAccess.getGreetingAccess().getExclamationMarkKeyword_2());

The created token has many=true and optional=false, which is wrong. It should be many=false and optional=true. The consequence of this is that the method emitUnassignedTokens(EObject, ISynTransition, INode, INode), which uses the created matching rules, never matches the optional exclamation mark during serialization and the emit_Greeting_ExclamationMarkKeyword_2_q(EObject, ISynNavigable, List<INode>) method is never called, so it is not possible to change the serialization of optional keywords. Changing or overriding the generated code by setting the correct values for 'many' and 'optional' fixes the problem.

Reproducible: Always

Steps to Reproduce:
1. Create a grammar with an optional keyword (use question mark).
2. Generate code with the new serializer.
3. Override the corresponding 'emit' method in the generated syntactic sequencer.
4. The overridden method is not considered during serialization.

Comment 1 Miro Spoenemann

2011-11-01 14:10:35 EDT

Created attachment 206283 [details]
Syntactic sequencer for the example grammar

Using this syntactic sequencer enforces serialization of the optional exclamation mark, but it works only if the TokenAlias creation in its superclass is modified as described.

Comment 2 Miro Spoenemann

2011-11-01 14:15:34 EDT

Created attachment 206284 [details]
Command handler that serializes a model to demonstrate the problem

Output without correcting AbstractMyDslSyntacticSequencer:

Hello world

Output after correcting the 'many' and 'optional' parameters of match_Greeting_ExclamationMarkKeyword_2_q:

Hello world !

Comment 3 Moritz Eysholdt

2011-11-09 07:04:21 EST

thanks for the detailed report.

Comment 4 Moritz Eysholdt

2011-11-09 08:06:10 EST

fixed in branches 'master' and '2.1.x_Maintenance'

Comment 5 Karsten Thoms

2017-09-19 17:55:42 EDT

Closing all bugs that were set to RESOLVED before Neon.0

Comment 6 Karsten Thoms

2017-09-19 18:06:27 EDT

Closing all bugs that were set to RESOLVED before Neon.0