pi-lens/rules/tree-sitter-queries/typescript/self-assignment.yml

Real-time code feedback for pi — LSP, linters, formatters, type-checking, structural analysis & booboo

# Self Assignment
# Detects variables assigned to themselves
id: self-assignment
name: Variables Should Not Be Self-Assigned
severity: error
category: reliability
defect_class: correctness
inline_tier: blocking
language: typescript

message: "'{{VAR}}' is assigned to itself"

description: |
  Self-assignment (x = x) has no effect and indicates a bug,
  usually from typo or incomplete refactoring.

  ✅ FIX: Fix the assignment or remove it

  ```typescript
  x = y;  // GOOD - actual intent
  ```

query: |
  (assignment_expression
    left: (identifier) @VAR
    right: (identifier) @SAME
    (#eq? @VAR @SAME))

metavars:
  - VAR
  - SAME

tags:
  - reliability
  - typescript
  - bugs
  - suspicious

examples:
  bad: |
    x = x;  // BAD - no effect

  good: |
    x = y;  // GOOD - actual assignment

has_fix: false