deep-compare-by

Deep compare with a function

const compare = require("deep-compare-by");
const cmp = compare((a, b) => (
    (typeof a === "function") &&
    (typeof b === "function") &&
    (a.toString() == b.toString())
));
cmp({
    a:1,
    b:{
        c:2,
        d:()=>4
    }
},{
    a:1,
    b:{
        c:2,
        d:()=>4
    }
}); // returns true

more examples can be found in test.js

Curryable

compare(test)(lhs)(rhs)
compare(test,lhs)(rhs)
compare(test)(lhs,rhs)
compare(test,lhs,rhs)

const cmp = compare(null,{a:1});
cmp({a:0}); // false
cmp({a:1}); // true
cmp({a:1,b:2}); // false

Arguments

compare(compareFunctions,lhs,rhs);

Compare Functions

This set of functions will be run to compare each object or value in the passed items, if any of the functions return true the corresponding items will be considered equivalent, there is an implicit test (a,b)=>a===b which exists unless using noDefault

compare(null); // same as compare []
compare((a,b)=>a<b); // same as [(a,b)=>a<b]
const cmp = compare(null);
const cmpt = compare([
    (a, b) => (typeof a === typeof b),
    (a, b) => (a === 9)
]);
cmp(1, 2); // false
cmpt(1, 2); // true
cmp(9, "8"); // false
cmpt(8, "8"); // false
cmpt(9, "8"); // true

Modifiers

Modifiers call a modified version of the function

noDefault

Call without implicit test (a,b)=>a===b

const cmp = compare.noDefault((a, b) => b === 3);
cmp({ a: 1 }, { a: 1 }); // false
cmp({ a: 1 }, { a: 3 }); // true
const cmp2 = compare((a, b) => b === 3, { a: 1 });
cmp2.noDefault({ a: 1 }); // false
cmp2.noDefault({ a: 3 }); // true

failPath

Instead of false, it returns the key path to the point where the compare failed. If it succeeds, return true;

const val1 = {
    a: { b: { c: 2 } },
    d: 3,
    e: { f: 4 },
};
const val2 = {
    a: { b: { c: 3 } },
    d: 3,
    e: { f: 4 },
};
compare(null).failPath(val1, val2); // ['a', 'b', 'c']
compare(null)(val1).failPath(val2); // ['a', 'b', 'c']

Content

Return data about the function

tests

Returns array of tests currently curried in

const cmp = compare(null);
cmp.tests(); // []
const cmpt = compare((a, b) => (typeof a === typeof b));
cmpt.tests(); // [(a, b) => (typeof a === typeof b)]

lhs

Returns lhs value currently curried in, otherwise undefined

compare(null,5).lhs(); // 5