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authorAdam Mathes <adam@adammathes.com>2026-02-13 21:34:48 -0800
committerAdam Mathes <adam@adammathes.com>2026-02-13 21:34:48 -0800
commit76cb9c2a39d477a64824a985ade40507e3bbade1 (patch)
tree41e997aa9c6f538d3a136af61dae9424db2005a9 /vanilla/node_modules/bidi-js/src/mirroring.js
parent819a39a21ac992b1393244a4c283bbb125208c69 (diff)
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feat(vanilla): add testing infrastructure and tests (NK-wjnczv)
Diffstat (limited to 'vanilla/node_modules/bidi-js/src/mirroring.js')
-rw-r--r--vanilla/node_modules/bidi-js/src/mirroring.js48
1 files changed, 48 insertions, 0 deletions
diff --git a/vanilla/node_modules/bidi-js/src/mirroring.js b/vanilla/node_modules/bidi-js/src/mirroring.js
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+++ b/vanilla/node_modules/bidi-js/src/mirroring.js
@@ -0,0 +1,48 @@
+import data from './data/bidiMirroring.data.js'
+import { parseCharacterMap } from './util/parseCharacterMap.js'
+
+let mirrorMap
+
+function parse () {
+ if (!mirrorMap) {
+ //const start = performance.now()
+ const { map, reverseMap } = parseCharacterMap(data, true)
+ // Combine both maps into one
+ reverseMap.forEach((value, key) => {
+ map.set(key, value)
+ })
+ mirrorMap = map
+ //console.log(`mirrored chars parsed in ${performance.now() - start}ms`)
+ }
+}
+
+export function getMirroredCharacter (char) {
+ parse()
+ return mirrorMap.get(char) || null
+}
+
+/**
+ * Given a string and its resolved embedding levels, build a map of indices to replacement chars
+ * for any characters in right-to-left segments that have defined mirrored characters.
+ * @param string
+ * @param embeddingLevels
+ * @param [start]
+ * @param [end]
+ * @return {Map<number, string>}
+ */
+export function getMirroredCharactersMap(string, embeddingLevels, start, end) {
+ let strLen = string.length
+ start = Math.max(0, start == null ? 0 : +start)
+ end = Math.min(strLen - 1, end == null ? strLen - 1 : +end)
+
+ const map = new Map()
+ for (let i = start; i <= end; i++) {
+ if (embeddingLevels[i] & 1) { //only odd (rtl) levels
+ const mirror = getMirroredCharacter(string[i])
+ if (mirror !== null) {
+ map.set(i, mirror)
+ }
+ }
+ }
+ return map
+}