Matching Declaration Name

ID

kotlin.matching_declaration_name

Severity

info

Remediation Complexity

trivial

Remediation Risk

medium

Remediation Effort

low

Resource

Naming Convention

Language

Kotlin

Tags

naming, readability

Description

Reports a .kt file that contains exactly one top-level class, interface, or object whose name does not match the file’s base name (the file name without the .kt extension).

Rationale

The Kotlin coding conventions state that when a file contains a single non-private top-level class or interface, the file name should match the declaration name. Aligning the file and the declaration name makes navigation, packaging, and code review predictable: a reader who sees UserService.kt expects exactly one top-level UserService.

// File: UserService.kt
class UserService { ... }            // OK — names match

// File: UserService.kt
class Helper { ... }                 // FLAW — declaration does not match file name

Remediation

Either rename the file to match the top-level declaration, or rename the declaration to match the file name. If the file is intentionally a collection of utilities with no single dominant type, add a second top-level declaration (the rule only flags files with exactly one top-level declaration).

References