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avoid-complex-conditions

Group: Complexity
Path: lint/complexity/avoid-complex-conditions
Default: Off, opt in
Origin: Falcon
Rule: 35 of 512

Flags boolean expressions with more logical operands than the configured threshold.

Each operand joined by && or || counts as one; parentheses and unary operators do not hide logical operands. Calls and comparisons are opaque operands, so callback bodies do not inflate their caller's complexity. Only the outermost connected logical expression is reported. Logical expressions inside calls and callbacks are checked independently.

Options

threshold (integer, default: 10) — maximum number of logical operands.

Invalid

example.dartdart

void f(bool a, bool b, bool c, bool d) {
  if (a && b && c && d) {}
  final x = a || b || c || d;
  final y = (a && b) || (c && d);
  if (!(a || b || c || d)) {}
  final z = a ? (b && c && d && a) : false;
  final callback = a && [1].any((x) => a && b && c && d);
  while (a && b && c && d) { break; }
}

Condition has 4 logical operands (max 3). Extract a named condition.

1void f(bool a, bool b, bool c, bool d) {

2 if (a && b && c && d) {}

∙

Condition has 4 logical operands (max 3). Extract a named condition.

2 if (a && b && c && d) {}

3 final x = a || b || c || d;

∙

Condition has 4 logical operands (max 3). Extract a named condition.

3 final x = a || b || c || d;

4 final y = (a && b) || (c && d);

∙

Condition has 4 logical operands (max 3). Extract a named condition.

4 final y = (a && b) || (c && d);

5 if (!(a || b || c || d)) {}

∙

Condition has 4 logical operands (max 3). Extract a named condition.

5 if (!(a || b || c || d)) {}

6 final z = a ? (b && c && d && a) : false;

∙

Condition has 4 logical operands (max 3). Extract a named condition.

6 final z = a ? (b && c && d && a) : false;

7 final callback = a && [1].any((x) => a && b && c && d);

∙

Condition has 4 logical operands (max 3). Extract a named condition.

7 final callback = a && [1].any((x) => a && b && c && d);

8 while (a && b && c && d) { break; }

∙

Valid

example.dartdart

void f(bool a, bool b, bool c) {
  if (a) {}
  if (a && b) {}
  if (a || b || c) {}
  final x = (a && b) || c;
  final y = !(a && b);
  while (a && b && c) { break; }
  final z = a && b && [1].any((x) => a || c);
  final fallback = (a ?? b) && c;
  final bits = (1 & 2) == (3 | 4);
}

Configure avoid-complex-conditions

Set its severity in falcon.json. See the configuration guide.

falcon.jsonjson

{
  "linter": {
    "rules": {
      "complexity": {
        "avoid-complex-conditions": "error"
      }
    }
  }
}

Or silence one occurrence with a suppression comment; the reason is required.

example.dartdart

// falcon-ignore lint/complexity/avoid-complex-conditions: <reason>

avoid-complex-loop-conditions
Flags loop conditions with more logical operands than the configured threshold.
avoid-function-literals-in-foreach-callsavoid_function_literals_in_foreach_calls
Flags a function literal passed to an Iterable's forEach.
avoid-if-with-many-branches
Reports long if/else-if chains; replace them with a switch or extracted helpers.
avoid-inverted-boolean-expressionsavoid_inverted_boolean_expressionsrecommended
Flags a doubly-negated boolean expression such as !!x.
avoid-long-records
Reports record values and record types with too many fields.
avoid-nested-conditional-expressionsavoid-nested-conditional-expressions
Flags a ternary conditional expression nested inside another ternary.
avoid-nested-ifavoid_nested_if
Flags an if statement whose then-branch contains nested if statements.
avoid-nested-switch-expressions
Reports deeply nested switch expressions.