🔬 test: Increase coverage.

Author: make-github-pseudonymous-again

package.json

@@ -75,6 +75,7 @@
     "@functional-abstraction/measure": "4.0.0",
     "@functional-abstraction/predicate": "4.0.0",
     "@iterable-iterator/chain": "2.0.1",
+    "@iterable-iterator/cycle": "^1.0.0",
     "@iterable-iterator/list": "1.0.1",
     "@iterable-iterator/map": "1.0.1",
     "@iterable-iterator/range": "2.1.0",

test/src/regression/digit/Four/splitDigit.js

@@ -0,0 +1,24 @@
+import test from 'ava';
+
+import {ABSTRACT_COUNTER as COUNTER} from '../../../_fixtures.js';
+
+import {empty} from '../../../../../src/index.js';
+
+const cover = (t, j) => {
+	t.true(Number.isInteger(j) && j >= 0 && j <= 3);
+	const x = {};
+	const n = 11;
+	let tree = empty(COUNTER);
+	for (let i = 0; i < n; ++i) tree = tree.push(x); // (1) ((3)(3)) (4)
+	const [left, right] = tree.split((m) => m >= n - j);
+	t.is(left.measure(), n - (j + 1));
+	t.is(right.measure(), j + 1);
+	t.deepEqual(Array.from(left.concat(right)), Array.from(tree));
+};
+
+cover.title = (title, i) => title ?? `cover ${i}`;
+
+test(cover, 0);
+test(cover, 1);
+test(cover, 2);
+test(cover, 3);

test/src/regression/digit/Two/splitDigit.js

@@ -0,0 +1,22 @@
+import test from 'ava';
+
+import {ABSTRACT_COUNTER as COUNTER} from '../../../_fixtures.js';
+
+import {empty} from '../../../../../src/index.js';
+
+const cover = (t, j) => {
+	t.true(Number.isInteger(j) && j >= 0 && j <= 1);
+	const x = {};
+	const n = 9;
+	let tree = empty(COUNTER);
+	for (let i = 0; i < n; ++i) tree = tree.push(x); // (1) ((3)(3)) (2)
+	const [left, right] = tree.split((m) => m >= n - j);
+	t.is(left.measure(), n - (j + 1));
+	t.is(right.measure(), j + 1);
+	t.deepEqual(Array.from(left.concat(right)), Array.from(tree));
+};
+
+cover.title = (title, i) => title ?? `cover ${i}`;
+
+test(cover, 0);
+test(cover, 1);

test/src/regression/lazy/app3.js

@@ -0,0 +1,20 @@
+import test from 'ava';
+
+import {nrepeat} from '@iterable-iterator/repeat';
+import {ABSTRACT_COUNTER as COUNTER} from '../../_fixtures.js';
+
+import {empty} from '../../../../src/index.js';
+
+test('cover', (t) => {
+	const x = {};
+	const n = 9;
+	let tree = empty(COUNTER);
+	for (let i = 0; i < n; ++i) tree = tree.push(x); // (1) ((3)(3)) (2)
+	tree = tree.init().init(); // (1) ((3)) (3)
+	const A = tree.concat(tree);
+	t.deepEqual(Array.from(A), Array.from(nrepeat(x, 2 * (n - 2))));
+
+	tree = tree.init().init().init(); // (1) () (3)
+	const B = tree.concat(tree);
+	t.deepEqual(Array.from(B), Array.from(nrepeat(x, 2 * (n - 5))));
+});

test/src/regression/lazy/cons.js

@@ -0,0 +1,16 @@
+import test from 'ava';
+
+import {nrepeat} from '@iterable-iterator/repeat';
+import {ABSTRACT_COUNTER as COUNTER} from '../../_fixtures.js';
+
+import {empty} from '../../../../src/index.js';
+
+test('cover', (t) => {
+	const x = {};
+	const n = 9;
+	let tree = empty(COUNTER);
+	for (let i = 0; i < n; ++i) tree = tree.push(x); // (1) ((3)(3)) (2)
+	tree = tree.init().init(); // (1) ((3)) (3)
+	tree = tree.cons(x).cons(x).cons(x).cons(x); // (2) ((3)(3)) (3)
+	t.deepEqual(Array.from(tree), Array.from(nrepeat(x, n + 2)));
+});

test/src/regression/lazy/last.js

@@ -0,0 +1,21 @@
+import test from 'ava';
+
+import {nrepeat} from '@iterable-iterator/repeat';
+import {ABSTRACT_COUNTER as COUNTER} from '../../_fixtures.js';
+
+import {empty} from '../../../../src/index.js';
+
+test('cover', (t) => {
+	const x = {};
+	const n = 9;
+	let tree = empty(COUNTER);
+	for (let i = 0; i < n; ++i) tree = tree.push(x); // (1) ((3)(3)) (2)
+	for (let i = 0; i < n; ++i) {
+		const copy = tree.init().push(x);
+		t.deepEqual(Array.from(copy), Array.from(nrepeat(x, n - i)));
+		t.false(copy.isEmpty());
+		tree = tree.init();
+	}
+
+	t.true(tree.isEmpty());
+});

test/src/regression/lazy/push.js

@@ -0,0 +1,16 @@
+import test from 'ava';
+
+import {nrepeat} from '@iterable-iterator/repeat';
+import {ABSTRACT_COUNTER as COUNTER} from '../../_fixtures.js';
+
+import {empty} from '../../../../src/index.js';
+
+test('cover', (t) => {
+	const x = {};
+	const n = 9;
+	let tree = empty(COUNTER);
+	for (let i = 0; i < n; ++i) tree = tree.push(x); // (1) ((3)(3)) (2)
+	tree = tree.init().init(); // (1) ((3)) (3)
+	tree = tree.push(x).push(x); // (1) ((3)(3)) (2)
+	t.deepEqual(Array.from(tree), Array.from(nrepeat(x, n)));
+});

test/src/regression/lazy/reversed.js

@@ -0,0 +1,15 @@
+import test from 'ava';
+
+import {nrepeat} from '@iterable-iterator/repeat';
+import {ABSTRACT_COUNTER as COUNTER} from '../../_fixtures.js';
+
+import {empty} from '../../../../src/index.js';
+
+test('cover', (t) => {
+	const x = {};
+	const n = 9;
+	let tree = empty(COUNTER);
+	for (let i = 0; i < n; ++i) tree = tree.push(x); // (1) ((3)(3)) (2)
+	tree = tree.init().init(); // (1) ((3)) (3)
+	t.deepEqual(Array.from(tree.reversed()), Array.from(nrepeat(x, n - 2)));
+});

test/src/regression/lazy/splitTree.js

@@ -0,0 +1,17 @@
+import test from 'ava';
+
+import {ABSTRACT_COUNTER as COUNTER} from '../../_fixtures.js';
+
+import {empty} from '../../../../src/index.js';
+
+test('cover', (t) => {
+	const x = {};
+	const n = 9;
+	let tree = empty(COUNTER);
+	for (let i = 0; i < n; ++i) tree = tree.push(x); // (1) ((3)(3)) (2)
+	tree = tree.init().init(); // (1) ((3)) (3)
+	const [left, right] = tree.split((m) => m >= 3);
+	t.is(left.measure(), 2);
+	t.is(right.measure(), n - 4);
+	t.deepEqual(Array.from(left.concat(right)), Array.from(tree));
+});

test/src/regression/node/reversed.js

@@ -0,0 +1,19 @@
+import test from 'ava';
+
+import {ncycle} from '@iterable-iterator/cycle';
+import {reversed} from '@iterable-iterator/reversed';
+import {range} from '@iterable-iterator/range';
+import {ABSTRACT_COUNTER as COUNTER} from '../../_fixtures.js';
+
+import {empty} from '../../../../src/index.js';
+
+test('cover', (t) => {
+	const n = 11;
+	let tree = empty(COUNTER);
+	for (let i = 0; i < n; ++i) tree = tree.push(i); // (1) ((3)(3)) (4)
+	tree = tree.concat(tree);
+	t.deepEqual(
+		Array.from(tree.reversed()),
+		Array.from(ncycle(reversed(range(n)), 2)),
+	);
+});