3 files changed, 86 insertions, 33 deletions

diff --git a/ext/mixed/js/display-generator.js b/ext/mixed/js/display-generator.js
index 326f3f54..90361328 100644
--- a/ext/mixed/js/display-generator.js
+++ b/ext/mixed/js/display-generator.js
@@ -305,7 +305,7 @@ class DisplayGenerator {
 
     createPitch(details) {
         const {expressions, reading, position, tags} = details;
-        const morae = DisplayGenerator._jpGetKanaMorae(reading);
+        const morae = jp.getKanaMorae(reading);
 
         const node = this._templateHandler.instantiate('term-pitch-accent');
 
@@ -324,8 +324,8 @@ class DisplayGenerator {
         n = node.querySelector('.term-pitch-accent-characters');
         for (let i = 0, ii = morae.length; i < ii; ++i) {
             const mora = morae[i];
-            const highPitch = DisplayGenerator._jpIsMoraPitchHigh(i, position);
-            const highPitchNext = DisplayGenerator._jpIsMoraPitchHigh(i + 1, position);
+            const highPitch = jp.isMoraPitchHigh(i, position);
+            const highPitchNext = jp.isMoraPitchHigh(i + 1, position);
 
             const n1 = this._templateHandler.instantiate('term-pitch-accent-character');
             const n2 = n1.querySelector('.term-pitch-accent-character-inner');
@@ -358,8 +358,8 @@ class DisplayGenerator {
 
         const pathPoints = [];
         for (let i = 0; i < ii; ++i) {
-            const highPitch = DisplayGenerator._jpIsMoraPitchHigh(i, position);
-            const highPitchNext = DisplayGenerator._jpIsMoraPitchHigh(i + 1, position);
+            const highPitch = jp.isMoraPitchHigh(i, position);
+            const highPitchNext = jp.isMoraPitchHigh(i + 1, position);
             const graphic = (highPitch && !highPitchNext ? '#term-pitch-accent-graph-dot-downstep' : '#term-pitch-accent-graph-dot');
             const x = `${i * 50 + 25}`;
             const y = highPitch ? '25' : '75';
@@ -376,7 +376,7 @@ class DisplayGenerator {
 
         pathPoints.splice(0, ii - 1);
         {
-            const highPitch = DisplayGenerator._jpIsMoraPitchHigh(ii, position);
+            const highPitch = jp.isMoraPitchHigh(ii, position);
             const x = `${ii * 50 + 25}`;
             const y = highPitch ? '25' : '75';
             const use = document.createElementNS(svgns, 'use');
@@ -532,30 +532,4 @@ class DisplayGenerator {
 
         return true;
     }
-
-    static _jpGetKanaMorae(text) {
-        // This function splits Japanese kana reading into its individual mora
-        // components. It is assumed that the text is well-formed.
-        const smallKanaSet = DisplayGenerator._smallKanaSet;
-        const morae = [];
-        let i;
-        for (const c of text) {
-            if (smallKanaSet.has(c) && (i = morae.length) > 0) {
-                morae[i - 1] += c;
-            } else {
-                morae.push(c);
-            }
-        }
-        return morae;
-    }
-
-    static _jpCreateSmallKanaSet() {
-        return new Set(Array.from('ぁぃぅぇぉゃゅょゎァィゥェォャュョヮ'));
-    }
-
-    static _jpIsMoraPitchHigh(moraIndex, pitchAccentPosition) {
-        return pitchAccentPosition === 0 ? (moraIndex > 0) : (moraIndex < pitchAccentPosition);
-    }
 }
-
-DisplayGenerator._smallKanaSet = DisplayGenerator._jpCreateSmallKanaSet();
diff --git a/ext/mixed/js/japanese.js b/ext/mixed/js/japanese.js
index 61a247b2..e6b9a8a0 100644
--- a/ext/mixed/js/japanese.js
+++ b/ext/mixed/js/japanese.js
@@ -64,6 +64,8 @@ const jp = (() => {
         [0xffe0, 0xffee]  // Currency markers
     ];
 
+    const SMALL_KANA_SET = new Set(Array.from('ぁぃぅぇぉゃゅょゎァィゥェォャュョヮ'));
+
 
     // Character code testing functions
 
@@ -112,6 +114,26 @@ const jp = (() => {
     }
 
 
+    // Mora functions
+
+    function isMoraPitchHigh(moraIndex, pitchAccentPosition) {
+        return pitchAccentPosition === 0 ? (moraIndex > 0) : (moraIndex < pitchAccentPosition);
+    }
+
+    function getKanaMorae(text) {
+        const morae = [];
+        let i;
+        for (const c of text) {
+            if (SMALL_KANA_SET.has(c) && (i = morae.length) > 0) {
+                morae[i - 1] += c;
+            } else {
+                morae.push(c);
+            }
+        }
+        return morae;
+    }
+
+
     // Exports
 
     return {
@@ -119,6 +141,8 @@ const jp = (() => {
         isCodePointKana,
         isCodePointJapanese,
         isStringEntirelyKana,
-        isStringPartiallyJapanese
+        isStringPartiallyJapanese,
+        isMoraPitchHigh,
+        getKanaMorae
     };
 })();
diff --git a/test/test-japanese.js b/test/test-japanese.js
index c5d220e7..eab632bf 100644
--- a/test/test-japanese.js
+++ b/test/test-japanese.js
@@ -392,6 +392,59 @@ function testDistributeFuriganaInflected() {
     }
 }
 
+function testIsMoraPitchHigh() {
+    const data = [
+        [[0, 0], false],
+        [[1, 0], true],
+        [[2, 0], true],
+        [[3, 0], true],
+
+        [[0, 1], true],
+        [[1, 1], false],
+        [[2, 1], false],
+        [[3, 1], false],
+
+        [[0, 2], true],
+        [[1, 2], true],
+        [[2, 2], false],
+        [[3, 2], false],
+
+        [[0, 3], true],
+        [[1, 3], true],
+        [[2, 3], true],
+        [[3, 3], false],
+
+        [[0, 4], true],
+        [[1, 4], true],
+        [[2, 4], true],
+        [[3, 4], true]
+    ];
+
+    for (const [[moraIndex, pitchAccentPosition], expected] of data) {
+        const actual = jp.isMoraPitchHigh(moraIndex, pitchAccentPosition);
+        assert.strictEqual(actual, expected);
+    }
+}
+
+function testGetKanaMorae() {
+    const data = [
+        ['かこ', ['か', 'こ']],
+        ['かっこ', ['か', 'っ', 'こ']],
+        ['カコ', ['カ', 'コ']],
+        ['カッコ', ['カ', 'ッ', 'コ']],
+        ['コート', ['コ', 'ー', 'ト']],
+        ['ちゃんと', ['ちゃ', 'ん', 'と']],
+        ['とうきょう', ['と', 'う', 'きょ', 'う']],
+        ['ぎゅう', ['ぎゅ', 'う']],
+        ['ディスコ', ['ディ', 'ス', 'コ']]
+    ];
+
+    for (const [text, expected] of data) {
+        const actual = jp.getKanaMorae(text);
+        vm.assert.deepStrictEqual(actual, expected);
+    }
+}
+
 
 function main() {
     testIsCodePointKanji();
@@ -408,6 +461,8 @@ function main() {
     testConvertAlphabeticToKana();
     testDistributeFurigana();
     testDistributeFuriganaInflected();
+    testIsMoraPitchHigh();
+    testGetKanaMorae();
 }