tree-sitter-nextflow

Nextflow grammar for tree-sitter.

Target: Nextflow Strict Syntax (v2 Parser) - NXF_SYNTAX_PARSER=v2

This grammar is designed to support Nextflow's strict syntax mode, focusing on the cleaner, more consistent v2 parser syntax patterns.

Features

• Core Nextflow Syntax: Process definitions, workflows, variable declarations
• Language Injection: Bash/shell syntax highlighting in script blocks
• Expressions: Binary operators, lists, maps, function calls
• Control Flow: If/else statements, blocks
• Channel Operations: Channel.from(), Channel.value(), Channel.of() with pipe operations

Development Status

Current Test Coverage: 28/80 tests passing (35%)

• ✅ Core Features: Variable declarations, process definitions, script injection
• ✅ Expressions: Binary operations, lists, maps, channel operations
• ✅ Control Flow: If/else statements, function calls
• 🚧 In Progress: String interpolation, advanced workflows, closures
• ⏳ Future: Configuration files, error handling, advanced channel operators

Future Enhancements

AST-grep Integration

This grammar is designed to support ast-grep for advanced Nextflow code analysis and transformation.

Setup Steps:

1. Build Dynamic Library:

   # Compile grammar as shared library for ast-grep
   tree-sitter build --output nextflow.so

2. Configure AST-grep (sgconfig.yml):

   customLanguages:
     nextflow:
       libraryPath: ./nextflow.so
       extensions: [nf, nextflow]
       expandoChar: "$"  # For Nextflow string interpolation

3. Usage Examples:

   # Search for process definitions
   ast-grep --lang nextflow 'process $NAME { $$$ }'
   
   # Find channel operations
   ast-grep --lang nextflow 'Channel.from($$$)'
   
   # Refactor variable declarations
   ast-grep --lang nextflow 'def $VAR = $VALUE' --replace 'val $VAR = $VALUE'

Benefits:

• Code Analysis: Search patterns across large Nextflow codebases
• Refactoring: Automated code transformations and migrations
• Quality Tools: Custom linting rules for Nextflow best practices
• IDE Features: Enhanced editor support and IntelliSense

References

• Nextflow ANTLR grammar
• Nextflow TextMate grammar
• AST-grep Custom Languages