🔬 test(nodes,from,concat,append,prepend): Increase coverage.

Author: make-github-pseudonymous-again

test/src/_fixtures.js

@@ -39,6 +39,12 @@ export const iterableToString = (iterable) => iterable.toString();
 export const fromToString = (measure, iterable) =>
 	`from(${measureToString(measure)}, ${iterableToString(iterable)})`;
 
+export const fromLeftToString = (measure, iterable) =>
+	`fromLeft(${measureToString(measure)}, ${iterableToString(iterable)})`;
+
+export const fromRightToString = (measure, iterable) =>
+	`fromRight(${measureToString(measure)}, ${iterableToString(iterable)})`;
+
 export const fromLeft = (M, iterable) => {
 	let tree = empty(M);
 	for (const x of iterable) tree = tree.push(x);

test/src/regression/digit/nodes/generated.js

@@ -5,12 +5,13 @@ import {product} from '@set-theory/cartesian-product';
 
 import {
 	ABSTRACT_COUNTER as COUNTER,
-	fromToString as f,
-	fromRight,
 	fromLeft,
+	fromRight,
+	fromLeftToString as fl,
+	fromRightToString as fr,
 } from '../../../_fixtures.js';
 
-const cover = (t, M, A, B) => {
+const flfr = (t, M, A, B) => {
 	const left = fromLeft(M, A);
 	const right = fromRight(M, B);
 	const tree = left.concat(right);
@@ -19,8 +20,24 @@ const cover = (t, M, A, B) => {
 	t.deepEqual(Array.from(tree), expected);
 };
 
-cover.title = (title, M, A, B) => title ?? `${f(M, A)}.concat(${f(M, B)})`;
+flfr.title = (title, M, A, B) => title ?? `${fl(M, A)}.concat(${fr(M, B)})`;
+
+const flifrt = (t, M, A, B) => {
+	const left = fromLeft(M, A).init();
+	const right = fromRight(M, B).tail();
+	const tree = left.concat(right);
+	const expected = Array.from(A).slice(0, -1).concat(Array.from(B).slice(1));
+	t.is(tree.measure(), expected.length);
+	t.deepEqual(Array.from(tree), expected);
+};
+
+flifrt.title = (title, M, A, B) =>
+	title ?? `${fl(M, A)}.init().concat(${fr(M, B)}.tail())`;
 
 for (const [m, n] of product([range(62)], 2)) {
-	test(cover, COUNTER, range(m), range(n));
+	test(flfr, COUNTER, range(m), range(n));
+}
+
+for (const [m, n] of product([range(19)], 2)) {
+	test(flifrt, COUNTER, range(m), range(n));
 }

test/src/regression/fast/fill_right.js

@@ -0,0 +1,18 @@
+import test from 'ava';
+
+import {range} from '@iterable-iterator/range';
+
+import {ABSTRACT_COUNTER as COUNTER, measure} from '../../_fixtures.js';
+
+import {empty} from '../../../../src/index.js';
+
+test('left instanceof Four', (t) => {
+	const tree = empty(COUNTER)
+		.append(range(2))
+		.cons(-1)
+		.cons(-2)
+		.cons(-3)
+		.append(range(2, 4));
+	t.deepEqual(Array.from(tree), Array.from(range(-3, 4)));
+	t.is(tree.measure(), measure(COUNTER, range(-3, 4)));
+});

test/src/regression/fast/from_by_filling.js

@@ -0,0 +1,30 @@
+import test from 'ava';
+
+import {tee} from '@iterable-iterator/tee';
+import {range} from '@iterable-iterator/range';
+
+import {
+	ABSTRACT_COUNTER as COUNTER,
+	measure,
+	measureToString,
+	iterableToString,
+} from '../../_fixtures.js';
+
+import {empty} from '../../../../src/index.js';
+
+const macro = (t, M, iterable) => {
+	const [copy1, copy2, copy3] = tee(iterable, 3);
+	const tree = empty(M).append(copy1);
+
+	t.is(tree.measure(), measure(M, copy2));
+
+	const expected = Array.from(copy3);
+	t.deepEqual(Array.from(tree), expected);
+};
+
+macro.title = (title, M, iterable) =>
+	title ?? `empty(${measureToString(M)}).append(${iterableToString(iterable)})`;
+
+for (const i of range(10)) {
+	test(macro, COUNTER, range(i));
+}