no-assign-mutated-array.md

Avoid assigning mutated arrays (no-assign-mutated-array)

This rule forbids the assignment of values returned by the fill, reverse and sort array methods. These methods modify the array in place and return the array itself. When assigned to a variable - or passed to a function as an argument - the code reads like it returns a modified copy of the array, but it does not.

Assignment is allowed in situations in which fill, reverse or sort is called on an intermediate array.

Rule details

Examples of incorrect code for this rule:

const sorted = names.sort();

print(names.sort());

Examples of correct code for this rule:

names.sort();

const sorted = names.map(({ first }) => first).sort();

names.sort();
print(names);

Options

This rule has no options.

Further reading

• Be Careful with Array Mutators