CodeQL documentation

Syntax error

ID: js/syntax-error
Kind: problem
Severity: recommendation
Precision: very-high
Tags:
   - reliability
   - correctness
   - language-features
Query suites:
   - javascript-security-and-quality.qls

Click to see the query in the CodeQL repository

Syntax errors prevent code from executing correctly. If a piece of code contains syntax errors, this most likely indicates that it is never run and thus is dead code that should be removed.

Recommendation

Fix the syntax error. It may also be worth investigating whether the file containing the erroneous code fragment is ever included from anywhere. If it is not, then it is dead code, which should be removed.

Example

In the following example, function findBox contains incomplete code: the string literal and its containing block statement are not properly terminated, leading to a syntax error.

function findBox() {
  return $("box.important

References

  • Ecma International, ECMAScript Language Definition, 5.1 Edition, Section 15.11.6.4. ECMA, 2011.