// jscs:disable requireUseStrict
var test = require('tape');
var functionBind = require('../implementation');
var getCurrentContext = function () { return this; };
test('functionBind is a function', function (t) {
t.equal(typeof functionBind, 'function');
t.end();
});
test('non-functions', function (t) {
var nonFunctions = [true, false, [], {}, 42, 'foo', NaN, /a/g];
t.plan(nonFunctions.length);
for (var i = 0; i < nonFunctions.length; ++i) {
try { functionBind.call(nonFunctions[i]); } catch (ex) {
t.ok(ex instanceof TypeError, 'throws when given ' + String(nonFunctions[i]));
}
}
t.end();
});
test('without a context', function (t) {
t.test('binds properly', function (st) {
var args, context;
var namespace = {
func: functionBind.call(function () {
args = Array.prototype.slice.call(arguments);
context = this;
})
};
namespace.func(1, 2, 3);
st.deepEqual(args, [1, 2, 3]);
st.equal(context, getCurrentContext.call());
st.end();
});
t.test('binds properly, and still supplies bound arguments', function (st) {
var args, context;
var namespace = {
func: functionBind.call(function () {
args = Array.prototype.slice.call(arguments);
context = this;
}, undefined, 1, 2, 3)
};
namespace.func(4, 5, 6);
st.deepEqual(args, [1, 2, 3, 4, 5, 6]);
st.equal(context, getCurrentContext.call());
st.end();
});
t.test('returns properly', function (st) {
var args;
var namespace = {
func: functionBind.call(function () {
args = Array.prototype.slice.call(arguments);
return this;
}, null)
};
var context = namespace.func(1, 2, 3);
st.equal(context, getCurrentContext.call(), 'returned context is namespaced context');
st.deepEqual(args, [1, 2, 3], 'passed arguments are correct');
st.end();
});
t.test('returns properly with bound arguments', function (st) {
var args;
var namespace = {
func: functionBind.call(function () {
args = Array.prototype.slice.call(arguments);
return this;
}, null, 1, 2, 3)
};
var context = namespace.func(4, 5, 6);
st.equal(context, getCurrentContext.call(), 'returned context is namespaced context');
st.deepEqual(args, [1, 2, 3, 4, 5, 6], 'passed arguments are correct');
st.end();
});
t.test('called as a constructor', function (st) {
var thunkify = function (value) {
return function () { return value; };
};
st.test('returns object value', function (sst) {
var expectedReturnValue = [1, 2, 3];
var Constructor = functionBind.call(thunkify(expectedReturnValue), null);
var result = new Constructor();
sst.equal(result, expectedReturnValue);
sst.end();
});
st.test('does not return primitive value', function (sst) {
var Constructor = functionBind.call(thunkify(42), null);
var result = new Constructor();
sst.notEqual(result, 42);
sst.end();
});
st.test('object from bound constructor is instance of original and bound constructor', function (sst) {
var A = function (x) {
this.name = x || 'A';
};
var B = functionBind.call(A, null, 'B');
var result = new B();
sst.ok(result instanceof B, 'result is instance of bound constructor');
sst.ok(result instanceof A, 'result is instance of original constructor');
sst.end();
});
st.end();
});
t.end();
});
test('with a context', function (t) {
t.test('with no bound arguments', function (st) {
var args, context;
var boundContext = {};
var namespace = {
func: functionBind.call(function () {
args = Array.prototype.slice.call(arguments);
context = this;
}, boundContext)
};
namespace.func(1, 2, 3);
st.equal(context, boundContext, 'binds a context properly');
st.deepEqual(args, [1, 2, 3], 'supplies passed arguments');
st.end();
});
t.test('with bound arguments', function (st) {
var args, context;
var boundContext = {};
var namespace = {
func: functionBind.call(function () {
args = Array.prototype.slice.call(arguments);
context = this;
}, boundContext, 1, 2, 3)
};
namespace.func(4, 5, 6);
st.equal(context, boundContext, 'binds a context properly');
st.deepEqual(args, [1, 2, 3, 4, 5, 6], 'supplies bound and passed arguments');
st.end();
});
t.test('returns properly', function (st) {
var boundContext = {};
var args;
var namespace = {
func: functionBind.call(function () {
args = Array.prototype.slice.call(arguments);
return this;
}, boundContext)
};
var context = namespace.func(1, 2, 3);
st.equal(context, boundContext, 'returned context is bound context');
st.notEqual(context, getCurrentContext.call(), 'returned context is not lexical context');
st.deepEqual(args, [1, 2, 3], 'passed arguments are correct');
st.end();
});
t.test('returns properly with bound arguments', function (st) {
var boundContext = {};
var args;
var namespace = {
func: functionBind.call(function () {
args = Array.prototype.slice.call(arguments);
return this;
}, boundContext, 1, 2, 3)
};
var context = namespace.func(4, 5, 6);
st.equal(context, boundContext, 'returned context is bound context');
st.notEqual(context, getCurrentContext.call(), 'returned context is not lexical context');
st.deepEqual(args, [1, 2, 3, 4, 5, 6], 'passed arguments are correct');
st.end();
});
t.test('passes the correct arguments when called as a constructor', function (st) {
var expected = { name: 'Correct' };
var namespace = {
Func: functionBind.call(function (arg) {
return arg;
}, { name: 'Incorrect' })
};
var returned = new namespace.Func(expected);
st.equal(returned, expected, 'returns the right arg when called as a constructor');
st.end();
});
t.test('has the new instance\'s context when called as a constructor', function (st) {
var actualContext;
var expectedContext = { foo: 'bar' };
var namespace = {
Func: functionBind.call(function () {
actualContext = this;
}, expectedContext)
};
var result = new namespace.Func();
st.equal(result instanceof namespace.Func, true);
st.notEqual(actualContext, expectedContext);
st.end();
});
t.end();
});
test('bound function length', function (t) {
t.test('sets a correct length without thisArg', function (st) {
var subject = functionBind.call(function (a, b, c) { return a + b + c; });
st.equal(subject.length, 3);
st.equal(subject(1, 2, 3), 6);
st.end();
});
t.test('sets a correct length with thisArg', function (st) {
var subject = functionBind.call(function (a, b, c) { return a + b + c; }, {});
st.equal(subject.length, 3);
st.equal(subject(1, 2, 3), 6);
st.end();
});
t.test('sets a correct length without thisArg and first argument', function (st) {
var subject = functionBind.call(function (a, b, c) { return a + b + c; }, undefined, 1);
st.equal(subject.length, 2);
st.equal(subject(2, 3), 6);
st.end();
});
t.test('sets a correct length with thisArg and first argument', function (st) {
var subject = functionBind.call(function (a, b, c) { return a + b + c; }, {}, 1);
st.equal(subject.length, 2);
st.equal(subject(2, 3), 6);
st.end();
});
t.test('sets a correct length without thisArg and too many arguments', function (st) {
var subject = functionBind.call(function (a, b, c) { return a + b + c; }, undefined, 1, 2, 3, 4);
st.equal(subject.length, 0);
st.equal(subject(), 6);
st.end();
});
t.test('sets a correct length with thisArg and too many arguments', function (st) {
var subject = functionBind.call(function (a, b, c) { return a + b + c; }, {}, 1, 2, 3, 4);
st.equal(subject.length, 0);
st.equal(subject(), 6);
st.end();
});
});