多维表格
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

163 lines
5.6 KiB

// this is derived from https://github.com/pacocoursey/cmdk
// The scores are arranged so that a continuous match of characters will
// result in a total score of 1.
//
// The best case, this character is a match, and either this is the start
// of the string, or the previous character was also a match.
const SCORE_CONTINUE_MATCH = 1.9
// A new match at the start of a word scores better than a new match
// elsewhere as it's more likely that the user will type the starts
// of fragments.
// NOTE: We score word jumps between spaces slightly higher than slashes, brackets
// hyphens, etc.
const SCORE_SPACE_WORD_JUMP = 1.0
const SCORE_NON_SPACE_WORD_JUMP = 0.8
// Any other match isn't ideal, but we include it for completeness.
const SCORE_CHARACTER_JUMP = 0.2
// If the user transposed two letters, it should be significantly penalized.
//
// i.e. "ouch" is more likely than "curtain" when "uc" is typed.
const SCORE_TRANSPOSITION = 0.3
// The goodness of a match should decay slightly with each missing
// character.
//
// i.e. "bad" is more likely than "bard" when "bd" is typed.
//
// This will not change the order of suggestions based on SCORE_* until
// 100 characters are inserted between matches.
const PENALTY_SKIPPED = 0.999
// The goodness of an exact-case match should be higher than a
// case-insensitive match by a small amount.
//
// i.e. "HTML" is more likely than "haml" when "HM" is typed.
//
// This will not change the order of suggestions based on SCORE_* until
// 1000 characters are inserted between matches.
const PENALTY_CASE_MISMATCH = 0.999999
// Match higher for letters closer to the beginning of the word
// const PENALTY_DISTANCE_FROM_START = 0.9
// If the word has more characters than the user typed, it should
// be penalised slightly.
//
// i.e. "html" is more likely than "html5" if I type "html".
//
// However, it may well be the case that there's a sensible secondary
// ordering (like alphabetical) that it makes sense to rely on when
// there are many prefix matches, so we don't make the penalty increase
// with the number of tokens.
const PENALTY_NOT_COMPLETE = 0.98
const IS_GAP_REGEXP = /[\\\/_+.#"@\[\(\{&]/
const COUNT_GAPS_REGEXP = /[\\\/_+.#"@\[\(\{&]/g
const IS_SPACE_REGEXP = /[\s-]/
const COUNT_SPACE_REGEXP = /[\s-]/g
function commandScoreInner(
string: string,
abbreviation: string,
lowerString: string,
lowerAbbreviation: string,
stringIndex: number,
abbreviationIndex: number,
memoizedResults: { [x: string]: number },
) {
if (abbreviationIndex === abbreviation.length) {
if (stringIndex === string.length) {
return SCORE_CONTINUE_MATCH
}
return PENALTY_NOT_COMPLETE
}
const memoizeKey = `${stringIndex},${abbreviationIndex}`
if (memoizedResults[memoizeKey] !== undefined) {
return memoizedResults[memoizeKey]
}
const abbreviationChar = lowerAbbreviation.charAt(abbreviationIndex)
let index = lowerString.indexOf(abbreviationChar, stringIndex)
let highScore = 0
let score, transposedScore, wordBreaks, spaceBreaks
while (index >= 0) {
score = commandScoreInner(
string,
abbreviation,
lowerString,
lowerAbbreviation,
index + 1,
abbreviationIndex + 1,
memoizedResults,
)
if (score > highScore) {
if (index === stringIndex) {
score *= SCORE_CONTINUE_MATCH
} else if (IS_GAP_REGEXP.test(string.charAt(index - 1))) {
score *= SCORE_NON_SPACE_WORD_JUMP
wordBreaks = string.slice(stringIndex, index - 1).match(COUNT_GAPS_REGEXP)
if (wordBreaks && stringIndex > 0) {
score *= PENALTY_SKIPPED ** wordBreaks.length
}
} else if (IS_SPACE_REGEXP.test(string.charAt(index - 1))) {
score *= SCORE_SPACE_WORD_JUMP
spaceBreaks = string.slice(stringIndex, index - 1).match(COUNT_SPACE_REGEXP)
if (spaceBreaks && stringIndex > 0) {
score *= PENALTY_SKIPPED ** spaceBreaks.length
}
} else {
score *= SCORE_CHARACTER_JUMP
if (stringIndex > 0) {
score *= PENALTY_SKIPPED ** (index - stringIndex)
}
}
if (string.charAt(index) !== abbreviation.charAt(abbreviationIndex)) {
score *= PENALTY_CASE_MISMATCH
}
}
if (
(score < SCORE_TRANSPOSITION && lowerString.charAt(index - 1) === lowerAbbreviation.charAt(abbreviationIndex + 1)) ||
(lowerAbbreviation.charAt(abbreviationIndex + 1) === lowerAbbreviation.charAt(abbreviationIndex) && // allow duplicate letters. Ref #7428
lowerString.charAt(index - 1) !== lowerAbbreviation.charAt(abbreviationIndex))
) {
transposedScore = commandScoreInner(
string,
abbreviation,
lowerString,
lowerAbbreviation,
index + 1,
abbreviationIndex + 2,
memoizedResults,
)
if (transposedScore * SCORE_TRANSPOSITION > score) {
score = transposedScore * SCORE_TRANSPOSITION
}
}
if (score > highScore) {
highScore = score
}
index = lowerString.indexOf(abbreviationChar, index + 1)
}
memoizedResults[memoizeKey] = highScore
return highScore
}
function formatInput(string: string) {
// convert all valid space characters to space so they match each other
return string.toLowerCase().replace(COUNT_SPACE_REGEXP, ' ')
}
export function commandScore(string: string, abbreviation: string): number {
/* NOTE:
* in the original, we used to do the lower-casing on each recursive call, but this meant that toLowerCase()
* was the dominating cost in the algorithm, passing both is a little ugly, but considerably faster.
*/
return commandScoreInner(string, abbreviation, formatInput(string), formatInput(abbreviation), 0, 0, {})
}