pi-lens/rules/tree-sitter-queries/typescript/incomplete-assertion.yml

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# TypeScript Incomplete Assertion
# Detects expect() chains that are never called (Jest/Vitest style).
# Chai property assertions (e.g. expect(foo).to.be.true) are excluded.
id: ts-incomplete-assertion
name: Incomplete Test Assertion
severity: error
category: testing
defect_class: correctness
inline_tier: blocking
language: typescript

message: "Incomplete assertion — expect() chain is not called"

description: |
  Jest and Vitest matchers are methods that must be called.
  `expect(foo).toBe` (without parentheses) or `expect(foo)` (without a
  matcher) does not actually assert anything. The test will pass silently.

  ✅ FIX: call the matcher: `expect(foo).toBe(true)`

query: |
  (call_expression
    function: (identifier) @EXPECT
    (#eq? @EXPECT "expect")
    arguments: (arguments)) @EXPR

metavars:
  - EXPECT
  - EXPR

post_filter: incomplete_assertion

has_fix: false

tags:
  - typescript
  - testing
  - jest
  - vitest
  - assertions

examples:
  bad: |
    expect(foo).toBe;        // BAD — matcher not called
    expect(foo).not.toBe;    // BAD — matcher not called
    expect(foo);             // BAD — no matcher at all

  good: |
    expect(foo).toBe(true);  // OK
    expect(foo).not.toBe(1); // OK