SPEL - Software Package for E3SM Land Model: Code Understanding and Functional Unit Testing

The Software Package for E3SM Land Model (SPEL) is a versatile tool designed to automate the creation and validation of unit tests for subroutines within the ELM code. By analyzing variable usage, control flow based on macros and namelist configurations, and ELM's Fortran codebase, SPEL captures code context, dependencies, and call tree structures. This analysis, stored in a database, addresses the challenges of understanding complex scientific codes. SPEL also automates the generation of standalone unit test programs, handling dependency analysis, code generation, and bit-for-bit verification. Streamlining testing, debugging, and code analysis, SPEL serves as a valuable asset for ELM development and maintenance.