sysmlpy — Project Status

Current version: v0.11.0

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Completed

Public API Classes

These classes are fully implemented, have programmatic construction, dump() serialization, and test coverage.

Class	SysML Keyword(s)	Notes
Package	package	Name, shortname, children, load_from_grammar
Model	(root)	Wraps packages; load from string
Part	part / part def	Typed by, children, load_from_grammar
Item	item / item def	Typed by, children
Attribute	attribute / attribute def	set_value/get_value with pint units
Port	port / port def	In/out/inout directed features, add attribute
Action	action / action def	Add in/out parameters, typed by, specializes
Reference	ref	Simple, typed, and redefinition (ref :>> name : Type;)
Requirement	requirement def / requirement	Subject, actor, doc, constraint, assume constraint
UseCase	use case def / use case	Subject, actor, include
Interface	interface def / interface	Add end, add connection
Message	message	From, to, of-type
State	state def / state	Transitions, entry/do/exit actions, .parent property
Transition	transition	Source, target, guard, trigger, effect
Constraint	constraint def / constraint	Assert constraint, derivation forms
AnalysisCase	analysis def / analysis	Subject, objective, result expression
VerificationCase	verification def / verification	Parse and load from grammar
Concern	concern def / concern	Parse and load from grammar
View	view def / view	Parse and load from grammar
Viewpoint	viewpoint def / viewpoint	Parse and load from grammar
Individual	individual def / individual	Parse and load from grammar
Metadata	metadata def / metadata	Parse and load from grammar
Rendering	rendering def / rendering	Parse and load from grammar
Allocation	allocation def / allocation	Parse and load from grammar
Flow	flow def / flow	Parse and load from grammar
Connection	connection def / connection	Parse and load from grammar
Calculation	calc def / calc	Parse and load from grammar
Enumeration	enum def / enum	Parse and load from grammar

Relationship Methods (on all Usage/Definition classes)

Method	Syntax
_set_typed_by()	: TypeName
_set_specializes()	:> SuperDef (definitions)
_set_subsets()	:> superset (usages)
_set_redefines()	:>> original

Parser

• ANTLR4 parser — default parser, using OMG grammar v2026.03.0
• load(), loads(), load_grammar() (public API)
• load_antlr(), load_grammar_antlr() (explicit ANTLR4 path)
• Full ANTLR4 visitor (antlr_visitor.py, ~10,800 lines) converting parse tree to internal dict representation
• Supports comments, documentation blocks, and annotating elements
• Supports Case, AnalysisCase, VerificationCase, and TradeStudy definitions
• State machine support: entry/do/exit actions, accept/send/perform/assign nodes, transitions with guards

Grammar Classes with get_definition()

The following grammar classes now have get_definition() for serialization (added in v0.10.0):

• FeatureChainMember, FeatureBinding, ResultExpressionMember, UsagePrefix
• PerformActionUsage, AcceptNodeDeclaration, SendNodeDeclaration
• SenderReceiverPart, EmptyParameterMember, StateAcceptActionUsage, StateSendActionUsage
• EffectBehaviorMember, GuardExpressionMember, NodeParameterMember, ReferenceUsage
• AssertConstraintUsage, RequirementConstraintMember, RequirementConstraintKind
• RequirementConstraintUsage, RequirementUsage, SatisfyRequirementUsage
• SatisfactionSubjectMember, SatisfactionParameter, SatisfactionFeatureValue, SatisfactionReferenceExpression
• FlowConnectionDefinition, ActionDefinition, RequirementDefinition, RequirementBody
• MultiplicityRelatedElement (handles FeatureReferenceExpression for variable bounds)
• QualifiedName (handles both names and parts keys)

Grammar Round-Trip Coverage (parse → dump)

34 / 56 tests passing (61%) as of 2026-05-17.

Category	Pass	Total	Notes
Packages	3	3	Comments, docs, package structure
Part definitions	1	1
Generalization / Subsetting / Redefinition	3	3
Enumerations	2	2
Parts	2	2
Items	1	1
Connections	0	1	Multiplicity in connect syntax
Ports	2	2
Interfaces	1	2	Interface decomposition still failing
Binding connectors	2	2
Flow connections	1	3	Definition and interface variants failing
Actions	5	5	All action tests now pass
States	0	5	State machine bodies not yet implemented
Expressions	4	4
Calculations	2	3	Nested :>> redefines in return not yet handled
Constraints	2	7	assert constraint, derivation, time constraints remaining
Requirements	0	4	Requirement body items not yet implemented
Analysis	0	3	Analysis case bodies not yet implemented
Total	34	56	61%

Test Coverage

Test file	Count	Scope
tests/class_test.py	53 tests	Programmatic API unit tests
tests/grammar_test.py	56 tests	Grammar round-trip (parse → dump)
tests/main_test.py	7 tests	load/loads/load_grammar integration
tests/conformance_test.py	123 tests	OMG XPect parse conformance suite

Documentation

• README.md — installation, basic usage examples
• docs/source/quickstart.md — step-by-step usage guide
• docs/source/conf.py / index.rst — Sphinx docs setup
• docs/IMPLEMENTATION_STATUS.md / IMPLEMENTATION_STATUS_V2.md — internal grammar class tracking

CI/CD

• GitHub Actions: Black auto-format, pytest + coverage, PyPI release via python-semantic-release

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In Progress

These features exist partially — either parse-in works but dump is incomplete, or implementation covers only some test cases.

Grammar Round-Trip (active work area)

The visitor (antlr_visitor.py) and grammar classes (grammar/classes.py) are the primary targets for round-trip improvements.

Public API Stubs (parse works, dump() partial or broken)

These classes are instantiated during Package.load_from_grammar() and hold the grammar tree, but the dump() / get_definition() path is incomplete for some body elements.

Class	SysML Keyword(s)	Status
State	state def / state	.parent property, transitions, entry/do/exit actions implemented; some body edge cases remain
Constraint	constraint def / constraint	Assert constraint and derivation forms now supported
Connection	connection def / connection	Multiplicity on connect-ends not parsed
Flow	flow connection def / flow	Definition and interface-body variants failing
Calculation	calc def / calc	Nested :>> redefines in return not yet handled
Enumeration	enum def	Largely working; edge cases remain

Internal Grammar Classes

Of the ~319 internal grammar classes in grammar/classes.py, approximately 175+ now have get_definition() implemented (up from ~145).

ANTLR4 Grammar Limitations

All known ANTLR grammar limitations have been resolved. The conformance suite passes at 100%.

Other Incomplete Items

• Typed-by in load_from_grammar — Type relationships are not preserved when loading elements from grammar (usage.py, marked Typed By)
• CHANGELOG — Not updated since v0.5.3; v0.6.0+ work needs a new entry

Known Bugs

Location	Description
definition.py	Duplicate elif inner_class == "ActionUsage" block — dead code
grammar/classes.py	PackageBodyElement name is hardcoded; !TODO This isn't always the case
grammar/classes.py	Identified broken code path; This won't work
definition.py (RootNamespace)	load_package_body() raises NotImplementedError for AliasMember and Import nodes

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Not Started

High Priority

Feature	Description
Grammar round-trip (dump)	Improve get_definition() coverage on grammar classes to increase parse→dump round-trip from 61% toward 100%
State machine bodies	StateBodyItem, entry/do/exit action members — blocks 5 state round-trip tests
Requirement bodies	Requirement-specific body items (subject, require constraint, frame) — blocks 4 requirement round-trip tests
Analysis case bodies	Subject, objective requirement, result expression — blocks 3 analysis round-trip tests
Typed-by preservation	Type relationships not preserved when loading elements from grammar (usage.py, marked Typed By)

Medium Priority

Feature	Description
Flow connection definition/interface	flow def and flow in interface bodies — blocks 2 flow tests
Connection multiplicity ends	connect X[0..1] to Y[1] multiplicity in connector ends — blocks 1 connection test
Interface decomposition	End-connector structure in decomposed interfaces — blocks 1 interface test
Nested :>> redefines in return	return attribute X : Type { :>> feature = expr; } — blocks Calculation Usages 2
Typed literal values	LiteralInteger, LiteralReal, LiteralString — needed for typed attribute values beyond pint quantities
Multiplicity ranges (connect ends)	[1..5] or [*] on connector end members

Low Priority

Feature	Description
~~Remove textX runtime~~	Done — textX tooling, grammar files, and CI references removed
~~Action parameters via loads()~~	Done — action body items (in/out params) now round-trip correctly
~~Binding connectors~~	Done — bind X = Y in action/part bodies round-trips correctly
Grammar auto-update pipeline	Automated refresh from the OMG KEBNF spec when new releases drop
Activity nodes	ActionNode, AssignmentNode, ControlNode, DecisionNode

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Conformance Test Suite

Source: SysML-v2-Pilot-Implementation-2026-03 (org.omg.sysml.xpect.tests) Library: 94 normative files bundled at src/sysmlpy/library/ (kernel/ systems/ domain/) Test files: 123 .sysml files under tests/sysmlv2/, each with a .error sidecar

Run with: pytest -m conformance

Current results (2026-05-17)

123 / 123 passing (100%)

Category	Files	Pass	Fail	Pass %
simpletests/	37	37	0	100%
validation/valid/	34	34	0	100%
validation/invalid/	47	47	0	100%
expression/	4	4	0	100%
linking/	1	1	0	100%
Total	123	123	0	100%

Remaining Failures

None. All 123 conformance tests pass.

Key Fixes (v0.11.0 — 2026-05-17)

Fix	Tests unblocked
Add LPAREN AS typeReference RPAREN to baseExpression in ANTLR grammar	ElementFilter.sysml — (as Type) cast syntax
Add ownedExpression DOT bodyExpression to ownedExpression in ANTLR grammar	PathExpressions.sysml — lambda/filter expressions
Handle filterPackage imports in _visit_import_rule_dict visitor	ElementFilter.sysml — vehicle1_c1::*[@Security]
Fix interface_part UnboundLocalError in _make_interface_usage_dict	InterfaceUsage_Invalid.sysml
Add get_definition() to SuccessionFlowConnectionUsage	ActionUsage.sysml
Add CaseDefinition to DefinitionElement dispatch table	CaseUsage.sysml
Fix UsageExtensionKeyword to handle keyword field directly	CaseSubjectObjective_Invalid.sysml, Verification_invalid.sysml

How to Add New Conformance Tests

1. Place .sysml file under tests/sysmlv2/<category>/
2. Add companion .error file (empty = expects parse success, non-empty = expected error regex)
3. Tests are auto-discovered by conformance_test.py:_collect()

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Summary Counts

Category	Count
Public API classes (complete)	27
Public API stubs (parse-only or partial)	0
Grammar classes with get_definition()	~175+ of 319
Grammar classes missing get_definition()	~144 of 319
Unit + grammar + integration tests	116 (53 unit + 56 grammar + 7 integration)
Grammar round-trip tests passing	34 / 56 (61%)
Conformance tests (2026-03 XPect suite)	123 total — 123 passing (100%)
Bundled standard library files	94 (36 kernel .kerml + 21 systems .sysml + 37 domain .sysml)