FoldRight fixes for Monoid/Semigroup · BackendJava/lambda@c1d2193

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Original file line number	Diff line number	Diff line change
`@@ -82,7 +82,7 @@ default A foldLeft(A a, Iterable<A> as) {`
`82`	`82`	`*/`
`83`	`83`	`@Override`
`84`	`84`	`default Lazy<A> foldRight(A a, Iterable<A> as) {`
`85`		`-return lazy(() -> flip().foldMap(id(), reverse(cons(a, as))));`
	`85`	`+return lazy(() -> flip().foldMap(id(), cons(a, reverse(as))));`
`86`	`86`	`}`
`87`	`87`
`88`	`88`	`/**`

Original file line number	Diff line number	Diff line change
`@@ -39,7 +39,7 @@ default A foldLeft(A a, Iterable<A> as) {`
`39`	`39`	`* @see FoldRight`
`40`	`40`	`*/`
`41`	`41`	`default Lazy<A> foldRight(A a, Iterable<A> as) {`
`42`		`-return FoldRight.foldRight((y, lazyX) -> lazyX.fmap(x -> apply(x, y)), lazy(a), as);`
	`42`	`+return FoldRight.foldRight((y, lazyX) -> lazyX.fmap(x -> apply(y, x)), lazy(a), as);`
`43`	`43`	`}`
`44`	`44`
`45`	`45`	`/**`

Original file line number	Diff line number	Diff line change
`@@ -29,7 +29,7 @@ public Fn1<Iterable<Object>, Iterable<Object>> createTestSubject() {`
`29`	`29`
`30`	`30`	`@Test`
`31`	`31`	`public void foldRightAccumulatesRightToLeft() {`
`32`		`-assertThat(foldRight((a, lazyB) -> lazyB.fmap(b -> explainFold().apply(a, b)),`
	`32`	`+assertThat(foldRight((a, lazyAcc) -> lazyAcc.fmap(acc -> explainFold().apply(a, acc)),`
`33`	`33`	`lazy("5"),`
`34`	`34`	`asList("1", "2", "3", "4"))`
`35`	`35`	`.value(),`

Original file line number	Diff line number	Diff line change
`@@ -1,6 +1,7 @@`
`1`	`1`	`package com.jnape.palatable.lambda.monoid;`
`2`	`2`
`3`	`3`	`import com.jnape.palatable.lambda.adt.Maybe;`
	`4`	`+import com.jnape.palatable.lambda.functor.builtin.Lazy;`
`4`	`5`	`import org.junit.Test;`
`5`	`6`
`6`	`7`	`import java.util.List;`
`@@ -10,6 +11,7 @@`
`10`	`11`	`import static com.jnape.palatable.lambda.monoid.Monoid.monoid;`
`11`	`12`	`import static java.util.Arrays.asList;`
`12`	`13`	`import static org.junit.Assert.assertEquals;`
	`14`	`+import static testsupport.functions.ExplainFold.explainFold;`
`13`	`15`
`14`	`16`	`public class MonoidTest {`
`15`	`17`
`@@ -25,6 +27,13 @@ public void reduceRight() {`
`25`	`27`	`assertEquals((Integer) 6, sum.reduceRight(asList(1, 2, 3)));`
`26`	`28`	`}`
`27`	`29`
	`30`	`+@Test`
	`31`	`+public void foldRight() {`
	`32`	`+Lazy<String> lazyString = monoid(explainFold()::apply, "0")`
	`33`	`+ .foldRight("4", asList("1", "2", "3"));`
	`34`	`+assertEquals("(1 + (2 + (3 + (4 + 0))))", lazyString.value());`
	`35`	`+ }`
	`36`	`+`
`28`	`37`	`@Test`
`29`	`38`	`public void foldMap() {`
`30`	`39`	`Monoid<Integer> sum = monoid(Integer::sum, 0);`

Original file line number	Diff line number	Diff line change
`@@ -4,18 +4,19 @@`
`4`	`4`
`5`	`5`	`import static java.util.Arrays.asList;`
`6`	`6`	`import static org.junit.Assert.assertEquals;`
	`7`	`+import static testsupport.functions.ExplainFold.explainFold;`
`7`	`8`
`8`	`9`	`public class SemigroupTest {`
`9`	`10`
`10`	`11`	`@Test`
`11`	`12`	`public void foldLeft() {`
`12`		`-Semigroup<Integer> sum = (x, y) -> x + y;`
`13`		`-assertEquals((Integer) 6, sum.foldLeft(0, asList(1, 2, 3)));`
	`13`	`+Semigroup<String> foldFn = explainFold()::apply;`
	`14`	`+assertEquals("(((0 + 1) + 2) + 3)", foldFn.foldLeft("0", asList("1", "2", "3")));`
`14`	`15`	`}`
`15`	`16`
`16`	`17`	`@Test`
`17`	`18`	`public void foldRight() {`
`18`		`-Semigroup<Integer> sum = (x, y) -> x + y;`
`19`		`-assertEquals((Integer) 6, sum.foldRight(0, asList(1, 2, 3)).value());`
	`19`	`+Semigroup<String> foldFn = explainFold()::apply;`
	`20`	`+assertEquals("(1 + (2 + (3 + 0)))", foldFn.foldRight("0", asList("1", "2", "3")).value());`
`20`	`21`	`}`
`21`	`22`	`}`

Original file line number	Diff line number	Diff line change
`@@ -7,6 +7,6 @@`
`7`	`7`	`public class ExplainFold {`
`8`	`8`
`9`	`9`	`public static Fn2<String, String, String> explainFold() {`
`10`		`-return (acc, x) -> format("(%s + %s)", acc, x);`
	`10`	`+return (x, y) -> format("(%s + %s)", x, y);`
`11`	`11`	`}`
`12`	`12`	`}`