test(liftFN): add compatibility tests

- create extendable base of monadic types

Closes #60

src/internal/algebraicStructures/Identity.js

@@ -0,0 +1,4 @@
+import { applicativeTrait, applyTrait, functorTrait } from './traits';
+
+
+export default { ...applicativeTrait, ...applyTrait, ...functorTrait };

src/internal/algebraicStructures/traits.js

@@ -0,0 +1,23 @@
+import fantasyLand from 'fantasy-land';
+
+
+export const applicativeTrait = {
+  of(value) {
+    return { ...this, value };
+  },
+};
+applicativeTrait[fantasyLand.of] = applicativeTrait.of;
+
+export const functorTrait = {
+  map(fn) {
+    return this.of(fn(this.value));
+  },
+};
+functorTrait[fantasyLand.map] = functorTrait.map;
+
+export const applyTrait = {
+  ap(monadWithApplyOfAFunction) {
+    return monadWithApplyOfAFunction.map(fn => fn(this.value));
+  },
+};
+applyTrait[fantasyLand.ap] = applyTrait.ap;

src/liftFN.js

@@ -1,31 +1,9 @@
-import fantasyLand from 'fantasy-land';
 import { curry, head, slice, reduce, ap as apR, curryN, map, add, flip } from 'ramda';
 
+import Identity from './internal/algebraicStructures/Identity';
 
-const applicativeTrait = {
-  of(value) {
-    return { ...this, value };
-  },
-};
-applicativeTrait[fantasyLand.of] = applicativeTrait.of;
-
-const functorTrait = {
-  map(fn) {
-    return this.of(fn(this.value));
-  },
-};
-functorTrait[fantasyLand.map] = functorTrait.map;
-
-const applyTrait = {
-  ap(monadWithApplyOfAFunction) {
-    return monadWithApplyOfAFunction.map(fn => fn(this.value));
-  },
-};
-applyTrait[fantasyLand.ap] = applyTrait.ap;
-
-const Monad = { ...applicativeTrait, ...functorTrait, ...applyTrait };
-const m1 = Monad.of(1);
-const m2 = Monad.of(2).map(add);
+const m1 = Identity.of(1);
+const m2 = Identity.of(2).map(add);
 
 
 export const createAp = (ap1, ap2) => {

test/liftFN.js

@@ -4,6 +4,8 @@ import { add, reduce } from 'ramda';
 
 import RA from '../src/index';
 import eq from './shared/eq';
+import { createAp } from '../src/liftFN';
+import Identity from '../src/internal/algebraicStructures/Identity';
 
 
 const addN = (...args) => reduce(add, 0, args);
@@ -40,11 +42,35 @@ describe('liftFN', function() {
 
   it('retain order of arguments', function() {
     eq(RA.liftFN(3, add3)(Maybe.Some('a'), Maybe.Some('b'), Maybe.Some('c')), Maybe.Some('abc'));
+    eq(RA.liftFN(3, add3)(Identity.of('a'), Identity.of('b'), Identity.of('c')), Identity.of('abc'));
   });
 
   it('is curried', function() {
     const f4 = RA.liftFN(4);
     eq(typeof f4, 'function');
     eq(f4(addN)(Maybe.Some(1), Maybe.Some(1), Maybe.Some(1), Maybe.Some(1)), Maybe.Some(4));
   });
+
+  it('test old fantasyland spec compatibility', function() {
+    const m1 = Identity.of(1);
+    const m2 = Identity.of(2).map(add);
+
+    eq(createAp(m1, m2)(m1, m2), Identity.of(3));
+  });
+
+  it('test new fantasyland spec compatibility', function() {
+    const m1 = Identity.of(1);
+    const m2 = Identity.of(2).map(add);
+    const ap = createAp(m1, m2);
+
+    eq(ap(m1, m2), Identity.of(3));
+  });
+
+  it('test old fantasyland spec compatibility', function() {
+    const m1 = Maybe.Some(1);
+    const m2 = Maybe.Some(2).map(add);
+    const ap = createAp(m1, m2);
+
+    eq(ap(m1, m2), Maybe.Some(3));
+  });
 });