eslint/curly Style
What it does
This rule enforces the use of curly braces {} for all control statements (if, else, for, while, do, with). It ensures that all blocks are enclosed in curly braces to improve code clarity and maintainability.
Why is this bad?
Omitting curly braces can reduce code readability and increase the likelihood of errors, especially in deeply nested or indented code. It can also lead to bugs if additional statements are added later without properly enclosing them in braces. Using curly braces consistently makes the code safer and easier to modify.
Examples
"all" (default)
Examples of incorrect code for this rule:
/* curly: ["error", "all"] */
if (foo) foo++;
while (bar) bar--;
do foo();
while (bar);Examples of correct code for this rule:
/* curly: ["error", "all"] */
if (foo) {
foo++;
}
while (bar) {
bar--;
}
do {
foo();
} while (bar);"multi"
Examples of incorrect code for this rule with the "multi" option:
/* curly: ["error", "multi"] */
if (foo) foo();
else {
bar();
baz();
}Examples of correct code for this rule with the "multi" option:
/* curly: ["error", "multi"] */
if (foo) foo();
else bar();"multi-line"
Examples of incorrect code for this rule with the "multi-line" option:
/* curly: ["error", "multi-line"] */
if (foo) foo();
else bar();
while (foo) foo();Examples of correct code for this rule with the "multi-line" option:
/* curly: ["error", "multi-line"] */
if (foo) foo();
else bar();
while (foo) foo();
while (true) {
doSomething();
doSomethingElse();
}"multi-or-nest"
Examples of incorrect code for this rule with the "multi-or-nest" option:
/* curly: ["error", "multi-or-nest"] */
if (foo) if (bar) bar();
while (foo) while (bar) bar();Examples of correct code for this rule with the "multi-or-nest" option:
/* curly: ["error", "multi-or-nest"] */
if (foo) {
if (bar) bar();
}
while (foo) {
while (bar) bar();
}"consistent"
When enabled, "consistent" enforces consistent use of braces within an if-else chain. If one branch of the chain uses braces, then all branches must use braces, even if not strictly required by the first option.
Examples of incorrect code with "multi" and "consistent":
/* curly: ["error", "multi", "consistent"] */
if (foo) {
bar();
baz();
} else qux();
if (foo) bar();
else {
baz();
qux();
}Examples of correct code with "multi" and "consistent":
/* curly: ["error", "multi", "consistent"] */
if (foo) {
bar();
baz();
} else {
qux();
}
if (foo) {
bar();
} else {
baz();
qux();
}Examples of incorrect code with "multi-line" and "consistent":
/* curly: ["error", "multi-line", "consistent"] */
if (foo) {
bar();
} else baz();Examples of correct code with "multi-line" and "consistent":
/* curly: ["error", "multi-line", "consistent"] */
if (foo) {
bar();
} else {
baz();
}Examples of incorrect code with "multi-or-nest" and "consistent":
/* curly: ["error", "multi-or-nest", "consistent"] */
if (foo) {
if (bar) baz();
} else qux();Examples of correct code with "multi-or-nest" and "consistent":
/* curly: ["error", "multi-or-nest", "consistent"] */
if (foo) {
if (bar) baz();
} else {
qux();
}Configuration
Configuration for the curly rule, specified as an array of one or two elements.
Examples:
["all"]- Require braces in all cases (default)["multi"]- Require braces only for multi-statement blocks["multi-line"]- Require braces for multi-line blocks["multi-or-nest"]- Require braces for nested or multi-line blocks["multi", "consistent"]- Multi mode with consistent braces in if-else chains
The 1st option
type: "all" | "multi" | "multi-line" | "multi-or-nest"
The enforcement type for the curly rule.
"all"
Require braces in all cases (default)
"multi"
Require braces only when there are multiple statements in the block
"multi-line"
Require braces when the block spans multiple lines
"multi-or-nest"
Require braces when the block is nested or spans multiple lines
The 2nd option
How to use
To enable this rule using the config file or in the CLI, you can use:
{
"rules": {
"curly": "error"
}
}oxlint --deny curly