wishthis/node_modules/value-or-function/index.js
2022-01-21 09:28:41 +01:00

113 lines
2.1 KiB
JavaScript

'use strict';
// Built-in types
var types = [
'object',
'number',
'string',
'symbol',
'boolean',
'date',
'function', // Weird to expose this
];
function normalize(coercer, value) {
if (typeof value === 'function') {
if (coercer === 'function') {
return value;
}
value = value.apply(this, slice(arguments, 2));
}
return coerce(this, coercer, value);
}
function coerce(ctx, coercer, value) {
// Handle built-in types
if (typeof coercer === 'string') {
if (coerce[coercer]) {
return coerce[coercer].call(ctx, value);
}
return typeOf(coercer, value);
}
// Handle custom coercer
if (typeof coercer === 'function') {
return coercer.call(ctx, value);
}
// Array of coercers, try in order until one returns a non-null value
var result;
coercer.some(function(coercer) {
result = coerce(ctx, coercer, value);
return result != null;
});
return result;
}
coerce.string = function(value) {
if (value != null &&
typeof value === 'object' &&
typeof value.toString === 'function') {
value = value.toString();
}
return typeOf('string', primitive(value));
};
coerce.number = function(value) {
return typeOf('number', primitive(value));
};
coerce.boolean = function(value) {
return typeOf('boolean', primitive(value));
};
coerce.date = function(value) {
value = primitive(value);
if (typeof value === 'number' && !isNaN(value) && isFinite(value)) {
return new Date(value);
}
};
function typeOf(type, value) {
if (typeof value === type) {
return value;
}
}
function primitive(value) {
if (value != null &&
typeof value === 'object' &&
typeof value.valueOf === 'function') {
value = value.valueOf();
}
return value;
}
function slice(value, from) {
return Array.prototype.slice.call(value, from);
}
// Add methods for each type
types.forEach(function(type) {
// Make it an array for easier concat
var typeArg = [type];
normalize[type] = function() {
var args = slice(arguments);
return normalize.apply(this, typeArg.concat(args));
};
});
module.exports = normalize;