Release version 0.5.0

[treiher]

• Update submodules
• Test GNAT Studio plugin
• Prepare release notes
• Add version to limitations labels
• Update limitations link in README
• Change version in code
• Upload to PyPI
• Add tag to git repository
• Publish release notes

Release Notes Draft

Preview Features

• Message checksums (Checksum specification #222, Checksum support in PyRFLX #240)
• Protocol sessions (Extend model by protocol sessions #47, Syntax for protocol sessions #291, Initial support of protocol sessions in SPARK #292, DHCP client #675)

General

• Achieve "Passing" level of CII Best Practices Badge Program (CII Best Practices Badge Program - "Passing" level #660)
• Enforce 100% test coverage (100% code coverage #334)
• Show bug box on fatal errors (Fatal errors #607, Information about optimization and version of dependencies in bug box #655)
• Add ping example app (Ping example #366)
• Improve language reference (Transform documentation to AsciiDoc #703)
• Support showing message graphs in GNAT Studio (Implement message graph viewer in GNAT Studio #345)

Specification / Model

• Improve specification parser (Langkit-based specification parser #547, Invalid dependency resolution #572)
• Change syntax of message types (Change message syntax #380, Unary minus unsupported in math expressions #432, Semantics of length aspect and attribute in message specification #421), sequence types (Naming of arrays / sequences #528) and package separators (Different syntax for package separator and field access #441)
• Enable specification of field conditions (Allow if-clause without then-clause in message specification #95, Change semantics of abbreviated form of field conditions #617)
• Add modulo operation (Modulo operation in conditions #476)
• Enable use of size of static types in expressions (Use size of static types in expressions #384, Size attribute is ambiguous #480)
• Add static type checking of expressions (Type-check expressions #87)
• Fix message verification (Boolean literals not correctly expanded for message types #388, Field of merged message cannot be referenced in outer condition #389, Unaccessible conditional fields in message types #410, Missing check of presence of field #413, Model verification with optional message fields #492, Failing verification of derived message #497, Naming conflict between enum literal and type name not detected  #520, Potentially undefined field not detected #522, Unqualified enum literal from different package undetected #530, Verification of message size #579)
• Add caching of verification result of message specifications (Caching of verified specifications #442)

SPARK Code Generation

• Switch from GNAT Community 2020 to GNAT Community 2021 (Support for GNAT Community 2021 #494)
• Fix code generation (Incorrect detection of possibly empty array field #375, Compilation fails when comparing field value with field size #479, Setting array field with size defined by message size #486, Length restriction for nested message not considered #356, Invalid code generation for message size calculation #500, Transitive inclusion of sequences breaks default instantiation #536, Unqualified enum literal from different package undetected #530, Refinement of subtype with itself does not compile #593, Unsatisfiable precondition for setter of opaque field #665)
• Change API of generated code (Setting array field with independent array #487, Appending independently created messages to array #514, Optimize preconditions related to buffer index type #548, Simplify setting of opaque fields #557, Simplify code generation caused by generic buffer type #659)

PyRFLX

• Enable type checking in external applications (Type hints not recognized #393)
• Change API (Iterate over packages in PyRFLX() #406, PyRFLX: let bytestring fail on invalid message #423, PyRFLX: Allow pyrflx object creation directly from model #467, ID class relies on assertion for validity check #529, Use dedicated exception types for set and parse errors #510)
• Fix message parsing and serialization (Assertion prevents generation of messages with empty payload #407, Broken message bit index calculation #503, Fields crossing octet-boundary not serialized correctly #531, Opaque field with zero length serialized as one byte #533, Messages cannot be parsed if Specification contains condition with Message'Size #525, AttributeError on determining field size #606, Using type size in condition yields exception #559, Always_Valid aspect unsupported #624)
• Improve performance (Message generation performance #344)

New Dependencies

• Python >=3.7
• attrs
• GNAT Community 2021 (GNAT compiler and SPARK verification tools)

[senier]

@treiher Did we verify if the GNAT Studio plugin works with the current code base and CE 2021?