ADR 002 Dual File Extensions

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type: decision title: ADR-002 Dual File Extensions created: '2026-05-25' updated: '2026-05-25' tags:

• domain/annotation status: active date: '2024-07-23' owner: isselab context: v0.0.5 related:
• 'Annotation Syntax'
• 'Feature Model Language'

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ADR-002: Dual File Extensions

Date: 2024-07-23 (v0.0.5)
Status: active

Decision

Support two file extensions for both mapping file types:

• .feature-to-folder and .feature-folder (both valid)
• .feature-to-file and .feature-file (both valid)

Context

Users were using both forms in practice. Standardising on one would have broken existing projects. Both extensions now register to the same language/parser.

Consequences

• Both extensions work identically — same parser, same completion, same highlighting
• feature-file / feature-folder are shorter aliases; feature-to-file / feature-to-folder are more descriptive
• Registered in plugin.xml as comma-separated extensions attribute on <fileType>

Related

• Annotation Syntax
• Feature Model Language