/
filters.ts
818 lines (677 loc) · 23.2 KB
/
filters.ts
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/*---------------------------------------------------------------------------------------------
* Copyright (c) Microsoft Corporation. All rights reserved.
* Licensed under the MIT License. See License.txt in the project root for license information.
*--------------------------------------------------------------------------------------------*/
import { CharCode } from 'vs/base/common/charCode';
import { LRUCache } from 'vs/base/common/map';
import * as strings from 'vs/base/common/strings';
export interface IFilter {
// Returns null if word doesn't match.
(word: string, wordToMatchAgainst: string): IMatch[] | null;
}
export interface IMatch {
start: number;
end: number;
}
// Combined filters
/**
* @returns A filter which combines the provided set
* of filters with an or. The *first* filters that
* matches defined the return value of the returned
* filter.
*/
export function or(...filter: IFilter[]): IFilter {
return function (word: string, wordToMatchAgainst: string): IMatch[] | null {
for (let i = 0, len = filter.length; i < len; i++) {
const match = filter[i](word, wordToMatchAgainst);
if (match) {
return match;
}
}
return null;
};
}
// Prefix
export const matchesStrictPrefix: IFilter = _matchesPrefix.bind(undefined, false);
export const matchesPrefix: IFilter = _matchesPrefix.bind(undefined, true);
function _matchesPrefix(ignoreCase: boolean, word: string, wordToMatchAgainst: string): IMatch[] | null {
if (!wordToMatchAgainst || wordToMatchAgainst.length < word.length) {
return null;
}
let matches: boolean;
if (ignoreCase) {
matches = strings.startsWithIgnoreCase(wordToMatchAgainst, word);
} else {
matches = wordToMatchAgainst.indexOf(word) === 0;
}
if (!matches) {
return null;
}
return word.length > 0 ? [{ start: 0, end: word.length }] : [];
}
// Contiguous Substring
export function matchesContiguousSubString(word: string, wordToMatchAgainst: string): IMatch[] | null {
const index = wordToMatchAgainst.toLowerCase().indexOf(word.toLowerCase());
if (index === -1) {
return null;
}
return [{ start: index, end: index + word.length }];
}
// Substring
export function matchesSubString(word: string, wordToMatchAgainst: string): IMatch[] | null {
return _matchesSubString(word.toLowerCase(), wordToMatchAgainst.toLowerCase(), 0, 0);
}
function _matchesSubString(word: string, wordToMatchAgainst: string, i: number, j: number): IMatch[] | null {
if (i === word.length) {
return [];
} else if (j === wordToMatchAgainst.length) {
return null;
} else {
if (word[i] === wordToMatchAgainst[j]) {
let result: IMatch[] | null = null;
if (result = _matchesSubString(word, wordToMatchAgainst, i + 1, j + 1)) {
return join({ start: j, end: j + 1 }, result);
}
return null;
}
return _matchesSubString(word, wordToMatchAgainst, i, j + 1);
}
}
// CamelCase
function isLower(code: number): boolean {
return CharCode.a <= code && code <= CharCode.z;
}
export function isUpper(code: number): boolean {
return CharCode.A <= code && code <= CharCode.Z;
}
function isNumber(code: number): boolean {
return CharCode.Digit0 <= code && code <= CharCode.Digit9;
}
function isWhitespace(code: number): boolean {
return (
code === CharCode.Space
|| code === CharCode.Tab
|| code === CharCode.LineFeed
|| code === CharCode.CarriageReturn
);
}
const wordSeparators = new Set<number>();
'`~!@#$%^&*()-=+[{]}\\|;:\'",.<>/?'
.split('')
.forEach(s => wordSeparators.add(s.charCodeAt(0)));
function isWordSeparator(code: number): boolean {
return isWhitespace(code) || wordSeparators.has(code);
}
function charactersMatch(codeA: number, codeB: number): boolean {
return (codeA === codeB) || (isWordSeparator(codeA) && isWordSeparator(codeB));
}
function isAlphanumeric(code: number): boolean {
return isLower(code) || isUpper(code) || isNumber(code);
}
function join(head: IMatch, tail: IMatch[]): IMatch[] {
if (tail.length === 0) {
tail = [head];
} else if (head.end === tail[0].start) {
tail[0].start = head.start;
} else {
tail.unshift(head);
}
return tail;
}
function nextAnchor(camelCaseWord: string, start: number): number {
for (let i = start; i < camelCaseWord.length; i++) {
const c = camelCaseWord.charCodeAt(i);
if (isUpper(c) || isNumber(c) || (i > 0 && !isAlphanumeric(camelCaseWord.charCodeAt(i - 1)))) {
return i;
}
}
return camelCaseWord.length;
}
function _matchesCamelCase(word: string, camelCaseWord: string, i: number, j: number): IMatch[] | null {
if (i === word.length) {
return [];
} else if (j === camelCaseWord.length) {
return null;
} else if (word[i] !== camelCaseWord[j].toLowerCase()) {
return null;
} else {
let result: IMatch[] | null = null;
let nextUpperIndex = j + 1;
result = _matchesCamelCase(word, camelCaseWord, i + 1, j + 1);
while (!result && (nextUpperIndex = nextAnchor(camelCaseWord, nextUpperIndex)) < camelCaseWord.length) {
result = _matchesCamelCase(word, camelCaseWord, i + 1, nextUpperIndex);
nextUpperIndex++;
}
return result === null ? null : join({ start: j, end: j + 1 }, result);
}
}
interface ICamelCaseAnalysis {
upperPercent: number;
lowerPercent: number;
alphaPercent: number;
numericPercent: number;
}
// Heuristic to avoid computing camel case matcher for words that don't
// look like camelCaseWords.
function analyzeCamelCaseWord(word: string): ICamelCaseAnalysis {
let upper = 0, lower = 0, alpha = 0, numeric = 0, code = 0;
for (let i = 0; i < word.length; i++) {
code = word.charCodeAt(i);
if (isUpper(code)) { upper++; }
if (isLower(code)) { lower++; }
if (isAlphanumeric(code)) { alpha++; }
if (isNumber(code)) { numeric++; }
}
const upperPercent = upper / word.length;
const lowerPercent = lower / word.length;
const alphaPercent = alpha / word.length;
const numericPercent = numeric / word.length;
return { upperPercent, lowerPercent, alphaPercent, numericPercent };
}
function isUpperCaseWord(analysis: ICamelCaseAnalysis): boolean {
const { upperPercent, lowerPercent } = analysis;
return lowerPercent === 0 && upperPercent > 0.6;
}
function isCamelCaseWord(analysis: ICamelCaseAnalysis): boolean {
const { upperPercent, lowerPercent, alphaPercent, numericPercent } = analysis;
return lowerPercent > 0.2 && upperPercent < 0.8 && alphaPercent > 0.6 && numericPercent < 0.2;
}
// Heuristic to avoid computing camel case matcher for words that don't
// look like camel case patterns.
function isCamelCasePattern(word: string): boolean {
let upper = 0, lower = 0, code = 0, whitespace = 0;
for (let i = 0; i < word.length; i++) {
code = word.charCodeAt(i);
if (isUpper(code)) { upper++; }
if (isLower(code)) { lower++; }
if (isWhitespace(code)) { whitespace++; }
}
if ((upper === 0 || lower === 0) && whitespace === 0) {
return word.length <= 30;
} else {
return upper <= 5;
}
}
export function matchesCamelCase(word: string, camelCaseWord: string): IMatch[] | null {
if (!camelCaseWord) {
return null;
}
camelCaseWord = camelCaseWord.trim();
if (camelCaseWord.length === 0) {
return null;
}
if (!isCamelCasePattern(word)) {
return null;
}
if (camelCaseWord.length > 60) {
return null;
}
const analysis = analyzeCamelCaseWord(camelCaseWord);
if (!isCamelCaseWord(analysis)) {
if (!isUpperCaseWord(analysis)) {
return null;
}
camelCaseWord = camelCaseWord.toLowerCase();
}
let result: IMatch[] | null = null;
let i = 0;
word = word.toLowerCase();
while (i < camelCaseWord.length && (result = _matchesCamelCase(word, camelCaseWord, 0, i)) === null) {
i = nextAnchor(camelCaseWord, i + 1);
}
return result;
}
// Matches beginning of words supporting non-ASCII languages
// If `contiguous` is true then matches word with beginnings of the words in the target. E.g. "pul" will match "Git: Pull"
// Otherwise also matches sub string of the word with beginnings of the words in the target. E.g. "gp" or "g p" will match "Git: Pull"
// Useful in cases where the target is words (e.g. command labels)
export function matchesWords(word: string, target: string, contiguous: boolean = false): IMatch[] | null {
if (!target || target.length === 0) {
return null;
}
let result: IMatch[] | null = null;
let i = 0;
word = word.toLowerCase();
target = target.toLowerCase();
while (i < target.length && (result = _matchesWords(word, target, 0, i, contiguous)) === null) {
i = nextWord(target, i + 1);
}
return result;
}
function _matchesWords(word: string, target: string, i: number, j: number, contiguous: boolean): IMatch[] | null {
if (i === word.length) {
return [];
} else if (j === target.length) {
return null;
} else if (!charactersMatch(word.charCodeAt(i), target.charCodeAt(j))) {
return null;
} else {
let result: IMatch[] | null = null;
let nextWordIndex = j + 1;
result = _matchesWords(word, target, i + 1, j + 1, contiguous);
if (!contiguous) {
while (!result && (nextWordIndex = nextWord(target, nextWordIndex)) < target.length) {
result = _matchesWords(word, target, i + 1, nextWordIndex, contiguous);
nextWordIndex++;
}
}
return result === null ? null : join({ start: j, end: j + 1 }, result);
}
}
function nextWord(word: string, start: number): number {
for (let i = start; i < word.length; i++) {
if (isWordSeparator(word.charCodeAt(i)) ||
(i > 0 && isWordSeparator(word.charCodeAt(i - 1)))) {
return i;
}
}
return word.length;
}
// Fuzzy
const fuzzyContiguousFilter = or(matchesPrefix, matchesCamelCase, matchesContiguousSubString);
const fuzzySeparateFilter = or(matchesPrefix, matchesCamelCase, matchesSubString);
const fuzzyRegExpCache = new LRUCache<string, RegExp>(10000); // bounded to 10000 elements
export function matchesFuzzy(word: string, wordToMatchAgainst: string, enableSeparateSubstringMatching = false): IMatch[] | null {
if (typeof word !== 'string' || typeof wordToMatchAgainst !== 'string') {
return null; // return early for invalid input
}
// Form RegExp for wildcard matches
let regexp = fuzzyRegExpCache.get(word);
if (!regexp) {
regexp = new RegExp(strings.convertSimple2RegExpPattern(word), 'i');
fuzzyRegExpCache.set(word, regexp);
}
// RegExp Filter
const match = regexp.exec(wordToMatchAgainst);
if (match) {
return [{ start: match.index, end: match.index + match[0].length }];
}
// Default Filter
return enableSeparateSubstringMatching ? fuzzySeparateFilter(word, wordToMatchAgainst) : fuzzyContiguousFilter(word, wordToMatchAgainst);
}
/**
* Match pattern againt word in a fuzzy way. As in IntelliSense and faster and more
* powerfull than `matchesFuzzy`
*/
export function matchesFuzzy2(pattern: string, word: string): IMatch[] | null {
const score = fuzzyScore(pattern, pattern.toLowerCase(), 0, word, word.toLowerCase(), 0, true);
return score ? createMatches(score) : null;
}
export function anyScore(pattern: string, lowPattern: string, _patternPos: number, word: string, lowWord: string, _wordPos: number): FuzzyScore {
const result = fuzzyScore(pattern, lowPattern, 0, word, lowWord, 0, true);
if (result) {
return result;
}
let matches = 0;
let score = 0;
let idx = _wordPos;
for (let patternPos = 0; patternPos < lowPattern.length && patternPos < _maxLen; ++patternPos) {
const wordPos = lowWord.indexOf(lowPattern.charAt(patternPos), idx);
if (wordPos >= 0) {
score += 1;
matches += 2 ** wordPos;
idx = wordPos + 1;
} else if (matches !== 0) {
// once we have started matching things
// we need to match the remaining pattern
// characters
break;
}
}
return [score, matches, _wordPos];
}
//#region --- fuzzyScore ---
export function createMatches(score: undefined | FuzzyScore, offset = 0): IMatch[] {
if (typeof score === 'undefined') {
return [];
}
const matches = score[1].toString(2);
const wordStart = score[2];
const res: IMatch[] = [];
for (let pos = wordStart; pos < _maxLen; pos++) {
if (matches[matches.length - (pos + 1)] === '1') {
const last = res[res.length - 1];
if (last && last.end === pos + offset) {
last.end = pos + offset + 1;
} else {
res.push({ start: pos + offset, end: pos + offset + 1 });
}
}
}
return res;
}
const _maxLen = 128;
function initTable() {
const table: number[][] = [];
const row: number[] = [0];
for (let i = 1; i <= _maxLen; i++) {
row.push(-i);
}
for (let i = 0; i <= _maxLen; i++) {
const thisRow = row.slice(0);
thisRow[0] = -i;
table.push(thisRow);
}
return table;
}
const _table = initTable();
const _scores = initTable();
const _arrows = <Arrow[][]>initTable();
const _debug = false;
function printTable(table: number[][], pattern: string, patternLen: number, word: string, wordLen: number): string {
function pad(s: string, n: number, pad = ' ') {
while (s.length < n) {
s = pad + s;
}
return s;
}
let ret = ` | |${word.split('').map(c => pad(c, 3)).join('|')}\n`;
for (let i = 0; i <= patternLen; i++) {
if (i === 0) {
ret += ' |';
} else {
ret += `${pattern[i - 1]}|`;
}
ret += table[i].slice(0, wordLen + 1).map(n => pad(n.toString(), 3)).join('|') + '\n';
}
return ret;
}
function printTables(pattern: string, patternStart: number, word: string, wordStart: number): void {
pattern = pattern.substr(patternStart);
word = word.substr(wordStart);
console.log(printTable(_table, pattern, pattern.length, word, word.length));
console.log(printTable(_arrows, pattern, pattern.length, word, word.length));
console.log(printTable(_scores, pattern, pattern.length, word, word.length));
}
function isSeparatorAtPos(value: string, index: number): boolean {
if (index < 0 || index >= value.length) {
return false;
}
const code = value.charCodeAt(index);
switch (code) {
case CharCode.Underline:
case CharCode.Dash:
case CharCode.Period:
case CharCode.Space:
case CharCode.Slash:
case CharCode.Backslash:
case CharCode.SingleQuote:
case CharCode.DoubleQuote:
case CharCode.Colon:
case CharCode.DollarSign:
return true;
default:
return false;
}
}
function isWhitespaceAtPos(value: string, index: number): boolean {
if (index < 0 || index >= value.length) {
return false;
}
const code = value.charCodeAt(index);
switch (code) {
case CharCode.Space:
case CharCode.Tab:
return true;
default:
return false;
}
}
function isUpperCaseAtPos(pos: number, word: string, wordLow: string): boolean {
return word[pos] !== wordLow[pos];
}
export function isPatternInWord(patternLow: string, patternPos: number, patternLen: number, wordLow: string, wordPos: number, wordLen: number): boolean {
while (patternPos < patternLen && wordPos < wordLen) {
if (patternLow[patternPos] === wordLow[wordPos]) {
patternPos += 1;
}
wordPos += 1;
}
return patternPos === patternLen; // pattern must be exhausted
}
const enum Arrow { Top = 0b1, Diag = 0b10, Left = 0b100 }
/**
* A tuple of three values.
* 0. the score
* 1. the matches encoded as bitmask (2^53)
* 2. the offset at which matching started
*/
export type FuzzyScore = [number, number, number];
export namespace FuzzyScore {
/**
* No matches and value `-100`
*/
export const Default: [-100, 0, 0] = <[-100, 0, 0]>Object.freeze([-100, 0, 0]);
export function isDefault(score?: FuzzyScore): score is [-100, 0, 0] {
return !score || (score[0] === -100 && score[1] === 0 && score[2] === 0);
}
}
export interface FuzzyScorer {
(pattern: string, lowPattern: string, patternPos: number, word: string, lowWord: string, wordPos: number, firstMatchCanBeWeak: boolean): FuzzyScore | undefined;
}
export function fuzzyScore(pattern: string, patternLow: string, patternStart: number, word: string, wordLow: string, wordStart: number, firstMatchCanBeWeak: boolean): FuzzyScore | undefined {
const patternLen = pattern.length > _maxLen ? _maxLen : pattern.length;
const wordLen = word.length > _maxLen ? _maxLen : word.length;
if (patternStart >= patternLen || wordStart >= wordLen || (patternLen - patternStart) > (wordLen - wordStart)) {
return undefined;
}
// Run a simple check if the characters of pattern occur
// (in order) at all in word. If that isn't the case we
// stop because no match will be possible
if (!isPatternInWord(patternLow, patternStart, patternLen, wordLow, wordStart, wordLen)) {
return undefined;
}
let row: number = 1;
let column: number = 1;
let patternPos = patternStart;
let wordPos = wordStart;
let hasStrongFirstMatch = false;
// There will be a match, fill in tables
for (row = 1, patternPos = patternStart; patternPos < patternLen; row++, patternPos++) {
for (column = 1, wordPos = wordStart; wordPos < wordLen; column++, wordPos++) {
const score = _doScore(pattern, patternLow, patternPos, patternStart, word, wordLow, wordPos);
if (patternPos === patternStart && score > 1) {
hasStrongFirstMatch = true;
}
_scores[row][column] = score;
const diag = _table[row - 1][column - 1] + (score > 1 ? 1 : score);
const top = _table[row - 1][column] + -1;
const left = _table[row][column - 1] + -1;
if (left >= top) {
// left or diag
if (left > diag) {
_table[row][column] = left;
_arrows[row][column] = Arrow.Left;
} else if (left === diag) {
_table[row][column] = left;
_arrows[row][column] = Arrow.Left | Arrow.Diag;
} else {
_table[row][column] = diag;
_arrows[row][column] = Arrow.Diag;
}
} else {
// top or diag
if (top > diag) {
_table[row][column] = top;
_arrows[row][column] = Arrow.Top;
} else if (top === diag) {
_table[row][column] = top;
_arrows[row][column] = Arrow.Top | Arrow.Diag;
} else {
_table[row][column] = diag;
_arrows[row][column] = Arrow.Diag;
}
}
}
}
if (_debug) {
printTables(pattern, patternStart, word, wordStart);
}
if (!hasStrongFirstMatch && !firstMatchCanBeWeak) {
return undefined;
}
_matchesCount = 0;
_topScore = -100;
_wordStart = wordStart;
_firstMatchCanBeWeak = firstMatchCanBeWeak;
_findAllMatches2(row - 1, column - 1, patternLen === wordLen ? 1 : 0, 0, false);
if (_matchesCount === 0) {
return undefined;
}
return [_topScore, _topMatch2, wordStart];
}
function _doScore(pattern: string, patternLow: string, patternPos: number, patternStart: number, word: string, wordLow: string, wordPos: number) {
if (patternLow[patternPos] !== wordLow[wordPos]) {
return -1;
}
if (wordPos === (patternPos - patternStart)) {
// common prefix: `foobar <-> foobaz`
// ^^^^^
if (pattern[patternPos] === word[wordPos]) {
return 7;
} else {
return 5;
}
} else if (isUpperCaseAtPos(wordPos, word, wordLow) && (wordPos === 0 || !isUpperCaseAtPos(wordPos - 1, word, wordLow))) {
// hitting upper-case: `foo <-> forOthers`
// ^^ ^
if (pattern[patternPos] === word[wordPos]) {
return 7;
} else {
return 5;
}
} else if (isSeparatorAtPos(wordLow, wordPos) && (wordPos === 0 || !isSeparatorAtPos(wordLow, wordPos - 1))) {
// hitting a separator: `. <-> foo.bar`
// ^
return 5;
} else if (isSeparatorAtPos(wordLow, wordPos - 1) || isWhitespaceAtPos(wordLow, wordPos - 1)) {
// post separator: `foo <-> bar_foo`
// ^^^
return 5;
} else {
return 1;
}
}
let _matchesCount: number = 0;
let _topMatch2: number = 0;
let _topScore: number = 0;
let _wordStart: number = 0;
let _firstMatchCanBeWeak: boolean = false;
function _findAllMatches2(row: number, column: number, total: number, matches: number, lastMatched: boolean): void {
if (_matchesCount >= 10 || total < -25) {
// stop when having already 10 results, or
// when a potential alignment as already 5 gaps
return;
}
let simpleMatchCount = 0;
while (row > 0 && column > 0) {
const score = _scores[row][column];
const arrow = _arrows[row][column];
if (arrow === Arrow.Left) {
// left -> no match, skip a word character
column -= 1;
if (lastMatched) {
total -= 5; // new gap penalty
} else if (matches !== 0) {
total -= 1; // gap penalty after first match
}
lastMatched = false;
simpleMatchCount = 0;
} else if (arrow & Arrow.Diag) {
if (arrow & Arrow.Left) {
// left
_findAllMatches2(
row,
column - 1,
matches !== 0 ? total - 1 : total, // gap penalty after first match
matches,
lastMatched
);
}
// diag
total += score;
row -= 1;
column -= 1;
lastMatched = true;
// match -> set a 1 at the word pos
matches += 2 ** (column + _wordStart);
// count simple matches and boost a row of
// simple matches when they yield in a
// strong match.
if (score === 1) {
simpleMatchCount += 1;
if (row === 0 && !_firstMatchCanBeWeak) {
// when the first match is a weak
// match we discard it
return undefined;
}
} else {
// boost
total += 1 + (simpleMatchCount * (score - 1));
simpleMatchCount = 0;
}
} else {
return undefined;
}
}
total -= column >= 3 ? 9 : column * 3; // late start penalty
// dynamically keep track of the current top score
// and insert the current best score at head, the rest at tail
_matchesCount += 1;
if (total > _topScore) {
_topScore = total;
_topMatch2 = matches;
}
}
//#endregion
//#region --- graceful ---
export function fuzzyScoreGracefulAggressive(pattern: string, lowPattern: string, patternPos: number, word: string, lowWord: string, wordPos: number, firstMatchCanBeWeak: boolean): FuzzyScore | undefined {
return fuzzyScoreWithPermutations(pattern, lowPattern, patternPos, word, lowWord, wordPos, true, firstMatchCanBeWeak);
}
export function fuzzyScoreGraceful(pattern: string, lowPattern: string, patternPos: number, word: string, lowWord: string, wordPos: number, firstMatchCanBeWeak: boolean): FuzzyScore | undefined {
return fuzzyScoreWithPermutations(pattern, lowPattern, patternPos, word, lowWord, wordPos, false, firstMatchCanBeWeak);
}
function fuzzyScoreWithPermutations(pattern: string, lowPattern: string, patternPos: number, word: string, lowWord: string, wordPos: number, aggressive: boolean, firstMatchCanBeWeak: boolean): FuzzyScore | undefined {
let top = fuzzyScore(pattern, lowPattern, patternPos, word, lowWord, wordPos, firstMatchCanBeWeak);
if (top && !aggressive) {
// when using the original pattern yield a result we`
// return it unless we are aggressive and try to find
// a better alignment, e.g. `cno` -> `^co^ns^ole` or `^c^o^nsole`.
return top;
}
if (pattern.length >= 3) {
// When the pattern is long enough then try a few (max 7)
// permutations of the pattern to find a better match. The
// permutations only swap neighbouring characters, e.g
// `cnoso` becomes `conso`, `cnsoo`, `cnoos`.
const tries = Math.min(7, pattern.length - 1);
for (let movingPatternPos = patternPos + 1; movingPatternPos < tries; movingPatternPos++) {
const newPattern = nextTypoPermutation(pattern, movingPatternPos);
if (newPattern) {
const candidate = fuzzyScore(newPattern, newPattern.toLowerCase(), patternPos, word, lowWord, wordPos, firstMatchCanBeWeak);
if (candidate) {
candidate[0] -= 3; // permutation penalty
if (!top || candidate[0] > top[0]) {
top = candidate;
}
}
}
}
}
return top;
}
function nextTypoPermutation(pattern: string, patternPos: number): string | undefined {
if (patternPos + 1 >= pattern.length) {
return undefined;
}
const swap1 = pattern[patternPos];
const swap2 = pattern[patternPos + 1];
if (swap1 === swap2) {
return undefined;
}
return pattern.slice(0, patternPos)
+ swap2
+ swap1
+ pattern.slice(patternPos + 2);
}
//#endregion