super-graph/internal/serv/web/build/static/media/autocompleteUtils.js.4ce7ba...

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2020-04-11 08:45:06 +02:00
/**
* Copyright (c) Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the license found in the
* LICENSE file in the root directory of this source tree.
*
* @flow
*/
import type {GraphQLField, GraphQLSchema, GraphQLType} from 'graphql';
import {isCompositeType} from 'graphql';
import {
SchemaMetaFieldDef,
TypeMetaFieldDef,
TypeNameMetaFieldDef,
} from 'graphql/type/introspection';
import type {
CompletionItem,
ContextToken,
State,
TypeInfo,
} from 'graphql-language-service-types';
// Utility for returning the state representing the Definition this token state
// is within, if any.
export function getDefinitionState(tokenState: State): ?State {
let definitionState;
forEachState(tokenState, state => {
switch (state.kind) {
case 'Query':
case 'ShortQuery':
case 'Mutation':
case 'Subscription':
case 'FragmentDefinition':
definitionState = state;
break;
}
});
return definitionState;
}
// Gets the field definition given a type and field name
export function getFieldDef(
schema: GraphQLSchema,
type: GraphQLType,
fieldName: string,
): ?GraphQLField<*, *> {
if (fieldName === SchemaMetaFieldDef.name && schema.getQueryType() === type) {
return SchemaMetaFieldDef;
}
if (fieldName === TypeMetaFieldDef.name && schema.getQueryType() === type) {
return TypeMetaFieldDef;
}
if (fieldName === TypeNameMetaFieldDef.name && isCompositeType(type)) {
return TypeNameMetaFieldDef;
}
if (type.getFields && typeof type.getFields === 'function') {
return (type.getFields()[fieldName]: any);
}
return null;
}
// Utility for iterating through a CodeMirror parse state stack bottom-up.
export function forEachState(
stack: State,
fn: (state: State) => ?TypeInfo,
): void {
const reverseStateStack = [];
let state = stack;
while (state && state.kind) {
reverseStateStack.push(state);
state = state.prevState;
}
for (let i = reverseStateStack.length - 1; i >= 0; i--) {
fn(reverseStateStack[i]);
}
}
export function objectValues(object: Object): Array<any> {
const keys = Object.keys(object);
const len = keys.length;
const values = new Array(len);
for (let i = 0; i < len; ++i) {
values[i] = object[keys[i]];
}
return values;
}
// Create the expected hint response given a possible list and a token
export function hintList(
token: ContextToken,
list: Array<CompletionItem>,
): Array<CompletionItem> {
return filterAndSortList(list, normalizeText(token.string));
}
// Given a list of hint entries and currently typed text, sort and filter to
// provide a concise list.
function filterAndSortList(
list: Array<CompletionItem>,
text: string,
): Array<CompletionItem> {
if (!text) {
return filterNonEmpty(list, entry => !entry.isDeprecated);
}
const byProximity = list.map(entry => ({
proximity: getProximity(normalizeText(entry.label), text),
entry,
}));
const conciseMatches = filterNonEmpty(
filterNonEmpty(byProximity, pair => pair.proximity <= 2),
pair => !pair.entry.isDeprecated,
);
const sortedMatches = conciseMatches.sort(
(a, b) =>
(a.entry.isDeprecated ? 1 : 0) - (b.entry.isDeprecated ? 1 : 0) ||
a.proximity - b.proximity ||
a.entry.label.length - b.entry.label.length,
);
return sortedMatches.map(pair => pair.entry);
}
// Filters the array by the predicate, unless it results in an empty array,
// in which case return the original array.
function filterNonEmpty(
array: Array<Object>,
predicate: (entry: Object) => boolean,
): Array<Object> {
const filtered = array.filter(predicate);
return filtered.length === 0 ? array : filtered;
}
function normalizeText(text: string): string {
return text.toLowerCase().replace(/\W/g, '');
}
// Determine a numeric proximity for a suggestion based on current text.
function getProximity(suggestion: string, text: string): number {
// start with lexical distance
let proximity = lexicalDistance(text, suggestion);
if (suggestion.length > text.length) {
// do not penalize long suggestions.
proximity -= suggestion.length - text.length - 1;
// penalize suggestions not starting with this phrase
proximity += suggestion.indexOf(text) === 0 ? 0 : 0.5;
}
return proximity;
}
/**
* Computes the lexical distance between strings A and B.
*
* The "distance" between two strings is given by counting the minimum number
* of edits needed to transform string A into string B. An edit can be an
* insertion, deletion, or substitution of a single character, or a swap of two
* adjacent characters.
*
* This distance can be useful for detecting typos in input or sorting
*
* @param {string} a
* @param {string} b
* @return {int} distance in number of edits
*/
function lexicalDistance(a: string, b: string): number {
let i;
let j;
const d = [];
const aLength = a.length;
const bLength = b.length;
for (i = 0; i <= aLength; i++) {
d[i] = [i];
}
for (j = 1; j <= bLength; j++) {
d[0][j] = j;
}
for (i = 1; i <= aLength; i++) {
for (j = 1; j <= bLength; j++) {
const cost = a[i - 1] === b[j - 1] ? 0 : 1;
d[i][j] = Math.min(
d[i - 1][j] + 1,
d[i][j - 1] + 1,
d[i - 1][j - 1] + cost,
);
if (i > 1 && j > 1 && a[i - 1] === b[j - 2] && a[i - 2] === b[j - 1]) {
d[i][j] = Math.min(d[i][j], d[i - 2][j - 2] + cost);
}
}
}
return d[aLength][bLength];
}