ESLintrequire or disallow spacing between function identifiers and their invocations (func-call-spacing)
The --fix option on the command line can automatically fix some of the problems reported by this rule.
When calling a function, developers may insert optional whitespace between the function's name and the parentheses that invoke it. The following pairs of function calls are equivalent:
alert('Hello');
alert ('Hello');
console.log(42);
console.log (42);
new Date();
new Date ();
Rule Details
This rule requires or disallows spaces between the function name and the opening parenthesis that calls it.
options
This rule has a string option:
"never"(default) disallows space between the function name and the opening parenthesis."always"requires space between the function name and the opening parenthesis.
Further, in "always" mode, a second object option is available that contains a single boolean allowNewlines property.
never
Examples of incorrect code for this rule with the default "never" option:
/*eslint func-call-spacing: ["error", "never"]*/
fn ();
fn
();
Examples of correct code for this rule with the default "never" option:
/*eslint func-call-spacing: ["error", "never"]*/
fn();
always
Examples of incorrect code for this rule with the "always" option:
/*eslint func-call-spacing: ["error", "always"]*/
fn();
fn
();
Examples of correct code for this rule with the "always" option:
/*eslint func-call-spacing: ["error", "always"]*/
fn ();
allowNewlines
By default, "always" does not allow newlines. To permit newlines when in "always" mode, set the allowNewlines option to true. Newlines are never required.
Examples of incorrect code for this rule with allowNewlines option enabled:
/*eslint func-call-spacing: ["error", "always", { "allowNewlines": true }]*/
fn();
Examples of correct code for this rule with the allowNewlines option enabled:
/*eslint func-call-spacing: ["error", "always", { "allowNewlines": true }]*/
fn (); // Newlines are never required.
fn
();
When Not To Use It
This rule can safely be turned off if your project does not care about enforcing a consistent style for spacing within function calls.
Related Rules
- no-spaced-func (deprecated)
Compatibility
Version
This rule was introduced in ESLint 3.3.0.