From a3e846685d795d81a369ff4b23f39ead31163095 Mon Sep 17 00:00:00 2001 From: Travis Ralston Date: Thu, 22 Apr 2021 16:24:41 -0600 Subject: [PATCH] Add array utility tests (and support upsampling in resample) See contained diff. The upsampling is important for Voice Messages, but is being done here because it's easier to add all the tests at once. This also introduces a new Object utility - that will be tested on its own commit. --- src/utils/arrays.ts | 51 ++++++-- src/utils/objects.ts | 20 ++- test/arrays-test.ts | 294 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 354 insertions(+), 11 deletions(-) create mode 100644 test/arrays-test.ts diff --git a/src/utils/arrays.ts b/src/utils/arrays.ts index 8ab66dfb29..cea377bfe9 100644 --- a/src/utils/arrays.ts +++ b/src/utils/arrays.ts @@ -1,5 +1,5 @@ /* -Copyright 2020 The Matrix.org Foundation C.I.C. +Copyright 2020, 2021 The Matrix.org Foundation C.I.C. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. @@ -15,23 +15,47 @@ limitations under the License. */ /** - * Quickly resample an array to have less data points. This isn't a perfect representation, - * though this does work best if given a large array to downsample to a much smaller array. - * @param {number[]} input The input array to downsample. + * Quickly resample an array to have less/more data points. If an input which is larger + * than the desired size is provided, it will be downsampled. Similarly, if the input + * is smaller than the desired size then it will be upsampled. + * @param {number[]} input The input array to resample. * @param {number} points The number of samples to end up with. - * @returns {number[]} The downsampled array. + * @returns {number[]} The resampled array. */ export function arrayFastResample(input: number[], points: number): number[] { - // Heavily inpired by matrix-media-repo (used with permission) + if (input.length === points) return input; // short-circuit a complicated call + + // Heavily inspired by matrix-media-repo (used with permission) // https://github.com/turt2live/matrix-media-repo/blob/abe72c87d2e29/util/util_audio/fastsample.go#L10 - const everyNth = Math.round(input.length / points); - const samples: number[] = []; - for (let i = 0; i < input.length; i += everyNth) { - samples.push(input[i]); + let samples: number[] = []; + if (input.length > points) { + // Danger: this loop can cause out of memory conditions if the input is too small. + const everyNth = Math.round(input.length / points); + for (let i = 0; i < input.length; i += everyNth) { + samples.push(input[i]); + } + } else { + // Smaller inputs mean we have to spread the values over the desired length. We + // end up overshooting the target length in doing this, so we'll resample down + // before returning. This recursion is risky, but mathematically should not go + // further than 1 level deep. + const spreadFactor = Math.ceil(points / input.length); + for (const val of input) { + samples.push(...arraySeed(val, spreadFactor)); + } + samples = arrayFastResample(samples, points); } + + // Sanity fill, just in case while (samples.length < points) { samples.push(input[input.length - 1]); } + + // Sanity trim, just in case + if (samples.length > points) { + samples = samples.slice(0, points); + } + return samples; } @@ -178,6 +202,13 @@ export class GroupedArray { constructor(private val: Map) { } + /** + * The value of this group, after all applicable alterations. + */ + public get value(): Map { + return this.val; + } + /** * Orders the grouping into an array using the provided key order. * @param keyOrder The key order. diff --git a/src/utils/objects.ts b/src/utils/objects.ts index e7f4f0f907..2c9361beba 100644 --- a/src/utils/objects.ts +++ b/src/utils/objects.ts @@ -1,5 +1,5 @@ /* -Copyright 2020 The Matrix.org Foundation C.I.C. +Copyright 2020, 2021 The Matrix.org Foundation C.I.C. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. @@ -141,3 +141,21 @@ export function objectKeyChanges(a: O, b: O): (keyof O)[] { export function objectClone(obj: O): O { return JSON.parse(JSON.stringify(obj)); } + +/** + * Converts a series of entries to an object. + * @param entries The entries to convert. + * @returns The converted object. + */ +// NOTE: Deprecated once we have Object.fromEntries() support. +// @ts-ignore - return type is complaining about non-string keys, but we know better +export function objectFromEntries(entries: Iterable<[K, V]>): {[k: K]: V} { + const obj: { + // @ts-ignore - same as return type + [k: K]: V} = {}; + for (const e of entries) { + // @ts-ignore - same as return type + obj[e[0]] = e[1]; + } + return obj; +} diff --git a/test/arrays-test.ts b/test/arrays-test.ts new file mode 100644 index 0000000000..33c4ee452e --- /dev/null +++ b/test/arrays-test.ts @@ -0,0 +1,294 @@ +/* +Copyright 2021 The Matrix.org Foundation C.I.C. + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +*/ + +import { + arrayDiff, + arrayFastClone, + arrayFastResample, + arrayHasDiff, + arrayHasOrderChange, + arrayMerge, + arraySeed, + arrayUnion, + ArrayUtil, + GroupedArray, +} from "../src/utils/arrays"; +import {objectFromEntries} from "../src/utils/objects"; + +function expectSample(i: number, input: number[], expected: number[]) { + console.log(`Resample case index: ${i}`); // for debugging test failures + const result = arrayFastResample(input, expected.length); + expect(result).toBeDefined(); + expect(result).toHaveLength(expected.length); + expect(result).toEqual(expected); +} + +describe('arrays', () => { + describe('arrayFastResample', () => { + it('should downsample', () => { + [ + {input: [1, 2, 3, 4, 5], output: [1, 4]}, // Odd -> Even + {input: [1, 2, 3, 4, 5], output: [1, 3, 5]}, // Odd -> Odd + {input: [1, 2, 3, 4], output: [1, 2, 3]}, // Even -> Odd + {input: [1, 2, 3, 4], output: [1, 3]}, // Even -> Even + ].forEach((c, i) => expectSample(i, c.input, c.output)); + }); + + it('should upsample', () => { + [ + {input: [1, 2, 3], output: [1, 1, 2, 2, 3, 3]}, // Odd -> Even + {input: [1, 2, 3], output: [1, 1, 2, 2, 3]}, // Odd -> Odd + {input: [1, 2], output: [1, 1, 1, 2, 2]}, // Even -> Odd + {input: [1, 2], output: [1, 1, 1, 2, 2, 2]}, // Even -> Even + ].forEach((c, i) => expectSample(i, c.input, c.output)); + }); + + it('should maintain sample', () => { + [ + {input: [1, 2, 3], output: [1, 2, 3]}, // Odd + {input: [1, 2], output: [1, 2]}, // Even + ].forEach((c, i) => expectSample(i, c.input, c.output)); + }); + }); + + describe('arraySeed', () => { + it('should create an array of given length', () => { + const val = 1; + const output = [val, val, val]; + const result = arraySeed(val, output.length); + expect(result).toBeDefined(); + expect(result).toHaveLength(output.length); + expect(result).toEqual(output); + }); + it('should maintain pointers', () => { + const val = {}; // this works because `{} !== {}`, which is what toEqual checks + const output = [val, val, val]; + const result = arraySeed(val, output.length); + expect(result).toBeDefined(); + expect(result).toHaveLength(output.length); + expect(result).toEqual(output); + }); + }); + + describe('arrayFastClone', () => { + it('should break pointer reference on source array', () => { + const val = {}; // we'll test to make sure the values maintain pointers too + const input = [val, val, val]; + const result = arrayFastClone(input); + expect(result).toBeDefined(); + expect(result).toHaveLength(input.length); + expect(result).toEqual(input); // we want the array contents to match... + expect(result).not.toBe(input); // ... but be a different reference + }); + }); + + describe('arrayHasOrderChange', () => { + it('should flag true on B ordering difference', () => { + const a = [1, 2, 3]; + const b = [3, 2, 1]; + const result = arrayHasOrderChange(a, b); + expect(result).toBe(true); + }); + + it('should flag false on no ordering difference', () => { + const a = [1, 2, 3]; + const b = [1, 2, 3]; + const result = arrayHasOrderChange(a, b); + expect(result).toBe(false); + }); + + it('should flag true on A length > B length', () => { + const a = [1, 2, 3, 4]; + const b = [1, 2, 3]; + const result = arrayHasOrderChange(a, b); + expect(result).toBe(true); + }); + + it('should flag true on A length < B length', () => { + const a = [1, 2, 3]; + const b = [1, 2, 3, 4]; + const result = arrayHasOrderChange(a, b); + expect(result).toBe(true); + }); + }); + + describe('arrayHasDiff', () => { + it('should flag true on A length > B length', () => { + const a = [1, 2, 3, 4]; + const b = [1, 2, 3]; + const result = arrayHasDiff(a, b); + expect(result).toBe(true); + }); + + it('should flag true on A length < B length', () => { + const a = [1, 2, 3]; + const b = [1, 2, 3, 4]; + const result = arrayHasDiff(a, b); + expect(result).toBe(true); + }); + + it('should flag true on element differences', () => { + const a = [1, 2, 3]; + const b = [4, 5, 6]; + const result = arrayHasDiff(a, b); + expect(result).toBe(true); + }); + + it('should flag false if same but order different', () => { + const a = [1, 2, 3]; + const b = [3, 1, 2]; + const result = arrayHasDiff(a, b); + expect(result).toBe(false); + }); + + it('should flag false if same', () => { + const a = [1, 2, 3]; + const b = [1, 2, 3]; + const result = arrayHasDiff(a, b); + expect(result).toBe(false); + }); + }); + + describe('arrayDiff', () => { + it('should see added from A->B', () => { + const a = [1, 2, 3]; + const b = [1, 2, 3, 4]; + const result = arrayDiff(a, b); + expect(result).toBeDefined(); + expect(result.added).toBeDefined(); + expect(result.removed).toBeDefined(); + expect(result.added).toHaveLength(1); + expect(result.removed).toHaveLength(0); + expect(result.added).toEqual([4]); + }); + + it('should see removed from A->B', () => { + const a = [1, 2, 3]; + const b = [1, 2]; + const result = arrayDiff(a, b); + expect(result).toBeDefined(); + expect(result.added).toBeDefined(); + expect(result.removed).toBeDefined(); + expect(result.added).toHaveLength(0); + expect(result.removed).toHaveLength(1); + expect(result.removed).toEqual([3]); + }); + + it('should see added and removed in the same set', () => { + const a = [1, 2, 3]; + const b = [1, 2, 4]; // note diff + const result = arrayDiff(a, b); + expect(result).toBeDefined(); + expect(result.added).toBeDefined(); + expect(result.removed).toBeDefined(); + expect(result.added).toHaveLength(1); + expect(result.removed).toHaveLength(1); + expect(result.added).toEqual([4]); + expect(result.removed).toEqual([3]); + }); + }); + + describe('arrayUnion', () => { + it('should return a union', () => { + const a = [1, 2, 3]; + const b = [1, 2, 4]; // note diff + const result = arrayUnion(a, b); + expect(result).toBeDefined(); + expect(result).toHaveLength(2); + expect(result).toEqual([1, 2]); + }); + + it('should return an empty array on no matches', () => { + const a = [1, 2, 3]; + const b = [4, 5, 6]; + const result = arrayUnion(a, b); + expect(result).toBeDefined(); + expect(result).toHaveLength(0); + }); + }); + + describe('arrayMerge', () => { + it('should merge 3 arrays with deduplication', () => { + const a = [1, 2, 3]; + const b = [1, 2, 4, 5]; // note missing 3 + const c = [6, 7, 8, 9]; + const result = arrayMerge(a, b, c); + expect(result).toBeDefined(); + expect(result).toHaveLength(9); + expect(result).toEqual([1, 2, 3, 4, 5, 6, 7, 8, 9]); + }); + + it('should deduplicate a single array', () => { + // dev note: this is technically an edge case, but it is described behaviour if the + // function is only provided one function (it'll merge the array against itself) + const a = [1, 1, 2, 2, 3, 3]; + const result = arrayMerge(a); + expect(result).toBeDefined(); + expect(result).toHaveLength(3); + expect(result).toEqual([1, 2, 3]); + }); + }); + + describe('ArrayUtil', () => { + it('should maintain the pointer to the given array', () => { + const input = [1, 2, 3]; + const result = new ArrayUtil(input); + expect(result.value).toBe(input); + }); + + it('should group appropriately', () => { + const input = [['a', 1], ['b', 2], ['c', 3], ['a', 4], ['a', 5], ['b', 6]]; + const output = { + 'a': [['a', 1], ['a', 4], ['a', 5]], + 'b': [['b', 2], ['b', 6]], + 'c': [['c', 3]], + }; + const result = new ArrayUtil(input).groupBy(p => p[0]); + expect(result).toBeDefined(); + expect(result.value).toBeDefined(); + + const asObject = objectFromEntries(result.value.entries()); + expect(asObject).toMatchObject(output); + }); + }); + + describe('GroupedArray', () => { + it('should maintain the pointer to the given map', () => { + const input = new Map([ + ['a', [1, 2, 3]], + ['b', [7, 8, 9]], + ['c', [4, 5, 6]], + ]); + const result = new GroupedArray(input); + expect(result.value).toBe(input); + }); + + it('should ordering by the provided key order', () => { + const input = new Map([ + ['a', [1, 2, 3]], + ['b', [7, 8, 9]], // note counting diff + ['c', [4, 5, 6]], + ]); + const output = [4, 5, 6, 1, 2, 3, 7, 8, 9]; + const keyOrder = ['c', 'a', 'b']; // note weird order to cause the `output` to be strange + const result = new GroupedArray(input).orderBy(keyOrder); + expect(result).toBeDefined(); + expect(result.value).toBeDefined(); + expect(result.value).toEqual(output); + }); + }); +}); +