fix: [no-extra-boolean-cast] inspect comma expressions and ?? express…

…ions.

Fixes eslint#18186

lib/rules/no-extra-boolean-cast.js

@@ -115,6 +115,19 @@ module.exports = {
  return isInFlaggedContext(node.parent);
  }
 
+ /*
+ * Check last expression only in a sequence, i.e. if ((1, 2, Boolean(3))) {}, since
+ * the others don't affect the result of the expression.
+ */
+ if (node.parent.type === "SequenceExpression" && node.parent.expressions.at(-1) === node) {
+ return isInFlaggedContext(node.parent);
+ }
+
+ // Check the right hand side of a `??` operator.
+ if (node.parent.type === "LogicalExpression" && node.parent.operator === "??" && node.parent.right === node) {
+ return isInFlaggedContext(node.parent);
+ }
+
  return isInBooleanContext(node) ||
  (isLogicalContext(node.parent) &&
 
@@ -157,6 +170,7 @@ module.exports = {
  if (previousNode.parent.type === "ChainExpression") {
  return needsParens(previousNode.parent, node);
  }
+
  if (isParenthesized(previousNode)) {
 
  // parentheses around the previous node will stay, so there is no need for an additional pair
@@ -174,6 +188,7 @@ module.exports = {
  case "DoWhileStatement":
  case "WhileStatement":
  case "ForStatement":
+ case "SequenceExpression":
  return false;
  case "ConditionalExpression":
  return precedence(node) <= precedence(parent);

tests/lib/rules/no-extra-boolean-cast.js

@@ -34,6 +34,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
  "for(Boolean(foo);;) {}",
  "for(;; Boolean(foo)) {}",
  "if (new Boolean(foo)) {}",
+ "if ((Boolean(1), 2)) {}",
  {
  code: "var foo = bar || !!baz",
  options: [{ enforceForLogicalOperands: true }]
@@ -2435,6 +2436,35 @@ ruleTester.run("no-extra-boolean-cast", rule, {
  ecmaVersion: 2020
  },
  errors: [{ messageId: "unexpectedCall" }]
+ },
+ {
+ code: "if ((1, 2, Boolean(3))) {}",
+ output: "if ((1, 2, 3)) {}",
+ errors: [{ messageId: "unexpectedCall" }]
+ },
+ {
+ code: "if (a ?? Boolean(b)) {}",
+ output: "if (a ?? b) {}",
+ options: [{ enforceForLogicalOperands: true }],
+ errors: [{ messageId: "unexpectedCall" }]
+ },
+ {
+ code: "if (a ?? Boolean(b)) {}",
+ output: "if (a ?? b) {}",
+ options: [{ enforceForLogicalOperands: false }],
+ errors: [{ messageId: "unexpectedCall" }]
+ },
+ {
+ code: "if ((a, b, c ?? (d, e, f ?? Boolean(g)))) {}",
+ output: "if ((a, b, c ?? (d, e, f ?? g))) {}",
+ options: [{ enforceForLogicalOperands: false }],
+ errors: [{ messageId: "unexpectedCall" }]
+ },
+ {
+ code: "if ((a, b, c ?? (d, e, f ?? Boolean(g)))) {}",
+ output: "if ((a, b, c ?? (d, e, f ?? g))) {}",
+ options: [{ enforceForLogicalOperands: true }],
+ errors: [{ messageId: "unexpectedCall" }]
  }
  ]
 });