Merge branch 'master' into testing

17 files changed, 1045 insertions, 112 deletions

diff --git a/test/data/dictionaries/valid-dictionary1/image.gif b/test/data/dictionaries/valid-dictionary1/image.gif
new file mode 100644
index 00000000..f089d07c
--- /dev/null
+++ b/test/data/dictionaries/valid-dictionary1/image.gif
diff --git a/test/data/dictionaries/valid-dictionary1/term_bank_1.json b/test/data/dictionaries/valid-dictionary1/term_bank_1.json
index 755d9f6a..a62ad117 100644
--- a/test/data/dictionaries/valid-dictionary1/term_bank_1.json
+++ b/test/data/dictionaries/valid-dictionary1/term_bank_1.json
@@ -30,5 +30,6 @@
     ["打ち込む", "ぶちこむ", "tag1 tag2", "v5", 29, ["definition1a (打ち込む, ぶちこむ)", "definition1b (打ち込む, ぶちこむ)"], 6, "tag3 tag4 tag5"],
     ["打ち込む", "ぶちこむ", "tag1 tag2", "v5", 30, ["definition2a (打ち込む, ぶちこむ)", "definition2b (打ち込む, ぶちこむ)"], 6, "tag3 tag4 tag5"],
     ["打ち込む", "ぶちこむ", "tag1 tag2", "v5", 31, ["definition3a (打ち込む, ぶちこむ)", "definition3b (打ち込む, ぶちこむ)"], 6, "tag3 tag4 tag5"],
-    ["打ち込む", "ぶちこむ", "tag1 tag2", "v5", 32, ["definition4a (打ち込む, ぶちこむ)", "definition4b (打ち込む, ぶちこむ)"], 6, "tag3 tag4 tag5"]
+    ["打ち込む", "ぶちこむ", "tag1 tag2", "v5", 32, ["definition4a (打ち込む, ぶちこむ)", "definition4b (打ち込む, ぶちこむ)"], 6, "tag3 tag4 tag5"],
+    ["画像", "がぞう", "tag1 tag2", "", 33, ["definition1a (画像, がぞう)", {"type": "image", "path": "image.gif", "width": 350, "height": 350, "description": "An image", "pixelated": true}], 7, "tag3 tag4 tag5"]
 ]
\ No newline at end of file
diff --git a/test/data/dictionaries/valid-dictionary1/term_meta_bank_1.json b/test/data/dictionaries/valid-dictionary1/term_meta_bank_1.json
index 26922394..73d74e68 100644
--- a/test/data/dictionaries/valid-dictionary1/term_meta_bank_1.json
+++ b/test/data/dictionaries/valid-dictionary1/term_meta_bank_1.json
@@ -2,6 +2,12 @@
     ["打", "freq", 1],
     ["打つ", "freq", 2],
     ["打ち込む", "freq", 3],
+    ["打", "freq", {"reading": "だ", "frequency": 4}],
+    ["打", "freq", {"reading": "ダース", "frequency": 5}],
+    ["打つ", "freq", {"reading": "うつ", "frequency": 6}],
+    ["打つ", "freq", {"reading": "ぶつ", "frequency": 7}],
+    ["打ち込む", "freq", {"reading": "うちこむ", "frequency": 8}],
+    ["打ち込む", "freq", {"reading": "ぶちこむ", "frequency": 9}],
     [
         "打ち込む",
         "pitch",
diff --git a/test/data/html/test-document1.html b/test/data/html/test-document1.html
index 0754a314..98a6fb44 100644
--- a/test/data/html/test-document1.html
+++ b/test/data/html/test-document1.html
@@ -103,6 +103,7 @@
         data-end-node-selector="img"
         data-end-offset="0"
         data-result-type="TextSourceElement"
+        data-sentence-extent="100"
         data-sentence="よみちゃん"
     >
         <img src="data:image/gif;base64,R0lGODdhBwAHAIABAAAAAP///ywAAAAABwAHAAACDIRvEaC32FpCbEkKCgA7" alt="よみちゃん" title="よみちゃん" style="width: 70px; height: 70px; image-rendering: crisp-edges; image-rendering: pixelated; display: block;" />
diff --git a/test/data/html/test-document2-frame1.html b/test/data/html/test-document2-frame1.html
index 3b85cdc5..e572e3c4 100644
--- a/test/data/html/test-document2-frame1.html
+++ b/test/data/html/test-document2-frame1.html
@@ -33,10 +33,8 @@ a, a:visited {
     ありがとう
 </div>
 <div>
-    <a href="#" id="fullscreen-link">Toggle fullscreen</a>
-    <script>
-document.querySelector('#fullscreen-link').addEventListener('click', () => toggleFullscreen(document.body), false);
-    </script>
+    <a href="#" class="fullscreen-link">Toggle fullscreen</a>
+    <script>setup(document.body, document.body);</script>
 </div>
 </div></body>
 </html>
\ No newline at end of file
diff --git a/test/data/html/test-document2-script.js b/test/data/html/test-document2-script.js
index bd5a570d..ab516a4e 100644
--- a/test/data/html/test-document2-script.js
+++ b/test/data/html/test-document2-script.js
@@ -39,3 +39,27 @@ function toggleFullscreen(element) {
         requestFullscreen(element);
     }
 }
+
+function setup(container, fullscreenElement=null) {
+    const fullscreenLink = container.querySelector('.fullscreen-link');
+    if (fullscreenLink !== null) {
+        if (fullscreenElement === null) {
+            fullscreenElement = container.querySelector('.fullscreen-element');
+        }
+        fullscreenLink.addEventListener('click', (e) => {
+            toggleFullscreen(fullscreenElement);
+            e.preventDefault();
+            return false;
+        }, false);
+    }
+
+    const template = container.querySelector('template');
+    const templateContentContainer = container.querySelector('.template-content-container');
+    if (template !== null && templateContentContainer !== null) {
+        const mode = container.dataset.shadowMode;
+        const shadow = templateContentContainer.attachShadow({mode});
+        const content = document.importNode(template.content, true);
+        setup(content);
+        shadow.appendChild(content);
+    }
+}
diff --git a/test/data/html/test-document2.html b/test/data/html/test-document2.html
index 3a22a5bf..6d174571 100644
--- a/test/data/html/test-document2.html
+++ b/test/data/html/test-document2.html
@@ -11,71 +11,78 @@
 <body>
 
     <h1>Yomichan Manual Tests</h1>
-    <p class="description">Manual tests involving fullscreen elements, &lt;iframe&gt;s, and shadow DOMs.</p>
+    <y-description>Manual tests involving fullscreen elements, &lt;iframe&gt;s, and shadow DOMs.</y-description>
 
-    <div class="test">
-        <div class="description">Standard content.</div>
-        <div id="fullscreen-element1" style="width: 100%; height: 200px; border: 1px solid #d8d8d8; position: relative;"><div style="background-color: #f8f8f8; padding: 0.5em; position: absolute; left: 0; top: 0; bottom: 0; right: 0;">
+    <y-test>
+        <y-description>Standard content.</y-description>
+        <div class="fullscreen-element" style="width: 100%; height: 200px; border: 1px solid #d8d8d8; position: relative;"><div style="background-color: #f8f8f8; padding: 0.5em; position: absolute; left: 0; top: 0; bottom: 0; right: 0;">
             <div>
                 ありがとう
             </div>
             <div>
-                <a href="#" id="fullscreen-link1">Toggle fullscreen</a>
+                <a href="#" class="fullscreen-link">Toggle fullscreen</a>
             </div>
         </div></div>
-        <script>
-document.querySelector('#fullscreen-link1').addEventListener('click', () => toggleFullscreen(document.querySelector('#fullscreen-element1')), false);
-        </script>
-    </div>
+    </y-test>
 
-    <div class="test">
-        <div class="description">Content inside of a shadow DOM.</div>
-        <div id="shadow-content-container"></div>
-        <template id="shadow-content-container-content-template">
+    <y-test data-shadow-mode="open">
+        <y-description>Content inside of an open shadow DOM.</y-description>
+        <div class="template-content-container"></div>
+        <template>
             <link rel="stylesheet" href="test-stylesheet.css" />
-            <div id="fullscreen-element2" style="width: 100%; height: 200px; border: 1px solid #d8d8d8; position: relative;"><div style="background-color: #f8f8f8; padding: 0.5em; position: absolute; left: 0; top: 0; bottom: 0; right: 0;">
+            <div class="fullscreen-element" style="width: 100%; height: 200px; border: 1px solid #d8d8d8; position: relative;"><div style="background-color: #f8f8f8; padding: 0.5em; position: absolute; left: 0; top: 0; bottom: 0; right: 0;">
                 <div>
                     ありがとう
                 </div>
                 <div>
-                    <a href="#" id="fullscreen-link2">Toggle fullscreen</a>
+                    <a href="#" class="fullscreen-link">Toggle fullscreen</a>
                 </div>
             </div></div>
         </template>
-        <script>
-(() => {
-    const shadowIframeContainer = document.querySelector('#shadow-content-container');
-    const shadow = shadowIframeContainer.attachShadow({mode: 'closed'});
-    const template = document.querySelector('#shadow-content-container-content-template').content;
-    const content = document.importNode(template, true);
-    const fullscreenElement = content.querySelector('#fullscreen-element2');
-    content.querySelector('#fullscreen-link2').addEventListener('click', () => toggleFullscreen(fullscreenElement), false);
-    shadow.appendChild(content);
-})();
-        </script>
-    </div>
+    </y-test>
 
-    <div class="test">
-        <div class="description">&lt;iframe&gt; element.</div>
+    <y-test data-shadow-mode="closed">
+        <y-description>Content inside of a closed shadow DOM.</y-description>
+        <div class="template-content-container"></div>
+        <template>
+            <link rel="stylesheet" href="test-stylesheet.css" />
+            <div class="fullscreen-element" style="width: 100%; height: 200px; border: 1px solid #d8d8d8; position: relative;"><div style="background-color: #f8f8f8; padding: 0.5em; position: absolute; left: 0; top: 0; bottom: 0; right: 0;">
+                <div>
+                    ありがとう
+                </div>
+                <div>
+                    <a href="#" class="fullscreen-link">Toggle fullscreen</a>
+                </div>
+            </div></div>
+        </template>
+    </y-test>
+
+    <y-test>
+        <y-description>&lt;iframe&gt; element.</y-description>
         <iframe src="test-document2-frame1.html" allowfullscreen="true" style="width: 100%; height: 200px; border: 1px solid #d8d8d8;"></iframe>
-    </div>
+    </y-test>
+
+    <y-test data-shadow-mode="open">
+        <y-description>&lt;iframe&gt; element inside of an open shadow DOM.</y-description>
+        <div class="template-content-container"></div>
+        <template>
+            <iframe src="test-document2-frame1.html" allowfullscreen="true" style="width: 100%; height: 200px; border: 1px solid #d8d8d8;"></iframe>
+        </template>
+    </y-test>
 
-    <div class="test">
-        <div class="description">&lt;iframe&gt; element inside of a shadow DOM.</div>
-        <div id="shadow-iframe-container"></div>
-        <template id="shadow-iframe-container-content-template">
+    <y-test data-shadow-mode="closed">
+        <y-description>&lt;iframe&gt; element inside of a closed shadow DOM.</y-description>
+        <div class="template-content-container"></div>
+        <template>
             <iframe src="test-document2-frame1.html" allowfullscreen="true" style="width: 100%; height: 200px; border: 1px solid #d8d8d8;"></iframe>
         </template>
-        <script>
-(() => {
-    const shadowIframeContainer = document.querySelector('#shadow-iframe-container');
-    const shadow = shadowIframeContainer.attachShadow({mode: 'closed'});
-    const template = document.querySelector('#shadow-iframe-container-content-template').content;
-    const content = document.importNode(template, true);
-    shadow.appendChild(content);
-})();
-        </script>
-    </div>
+    </y-test>
+
+    <script>
+for (const element of document.querySelectorAll('y-test')) {
+    setup(element);
+}
+    </script>
 
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/test/data/html/test-document3-frame1.html b/test/data/html/test-document3-frame1.html
new file mode 100644
index 00000000..2ae906d2
--- /dev/null
+++ b/test/data/html/test-document3-frame1.html
@@ -0,0 +1,44 @@
+<!DOCTYPE html>
+<html>
+    <head>
+        <meta charset="UTF-8">
+        <meta name="viewport" content="width=device-width,initial-scale=1" />
+        <title>Yomichan Manual Performance Tests</title>
+        <link rel="stylesheet" href="test-stylesheet.css" />
+    </head>
+<body><div class="content">
+
+    <div class="description">Add elements</div>
+
+    <div>
+        <a href="#" id="add-elements-1000">1000</a>
+        <a href="#" id="add-elements-10000">10000</a>
+        <a href="#" id="add-elements-100000">100000</a>
+        <a href="#" id="add-elements-1000000">1000000</a>
+        <script>
+document.querySelector('#add-elements-1000').addEventListener('click',    () => addElements(1000), false);
+document.querySelector('#add-elements-10000').addEventListener('click',   () => addElements(10000), false);
+document.querySelector('#add-elements-100000').addEventListener('click',  () => addElements(100000), false);
+document.querySelector('#add-elements-1000000').addEventListener('click', () => addElements(1000000), false);
+
+let counter = 0;
+
+function addElements(amount) {
+    const container = document.querySelector('#container');
+    for (let i = 0; i < amount; i++) {
+        const element = document.createElement('div');
+        element.textContent = 'ありがとう';
+        container.appendChild(element);
+    }
+
+    counter += amount;
+    document.querySelector('#counter').textContent = counter;
+}
+        </script>
+    </div>
+
+    <div id="counter"></div>
+    <div id="container"></div>
+
+</div></body>
+</html>
diff --git a/test/data/html/test-document3-frame2.html b/test/data/html/test-document3-frame2.html
new file mode 100644
index 00000000..c486e04b
--- /dev/null
+++ b/test/data/html/test-document3-frame2.html
@@ -0,0 +1,62 @@
+<!DOCTYPE html>
+<html>
+    <head>
+        <meta charset="UTF-8">
+        <meta name="viewport" content="width=device-width,initial-scale=1" />
+        <title>Yomichan Manual Performance Tests</title>
+        <link rel="stylesheet" href="test-stylesheet.css" />
+    </head>
+<body><div class="content">
+
+    <div class="description">&lt;iframe&gt; element inside of an open shadow DOM.</div>
+
+    <div id="shadow-iframe-container-open"></div>
+    <template id="shadow-iframe-container-open-content-template">
+        <iframe src="test-document2-frame1.html" allowfullscreen="true" style="width: 100%; height: 50px; border: 1px solid #d8d8d8;"></iframe>
+    </template>
+    <script>
+(() => {
+    const shadowIframeContainer = document.querySelector('#shadow-iframe-container-open');
+    const shadow = shadowIframeContainer.attachShadow({mode: 'open'});
+    const template = document.querySelector('#shadow-iframe-container-open-content-template').content;
+    const content = document.importNode(template, true);
+    shadow.appendChild(content);
+})();
+    </script>
+
+    <div class="description">Add elements</div>
+
+    <div>
+        <a href="#" id="add-elements-1000">1000</a>
+        <a href="#" id="add-elements-10000">10000</a>
+        <a href="#" id="add-elements-100000">100000</a>
+        <a href="#" id="add-elements-1000000">1000000</a>
+    </div>
+
+    <div id="counter"></div>
+    <div id="container"></div>
+    <script>
+(() => {
+    document.querySelector('#add-elements-1000').addEventListener('click',    () => addElements(1000), false);
+    document.querySelector('#add-elements-10000').addEventListener('click',   () => addElements(10000), false);
+    document.querySelector('#add-elements-100000').addEventListener('click',  () => addElements(100000), false);
+    document.querySelector('#add-elements-1000000').addEventListener('click', () => addElements(1000000), false);
+
+    let counter = 0;
+
+    function addElements(amount) {
+        const container = document.querySelector('#container');
+        for (let i = 0; i < amount; i++) {
+            const element = document.createElement('div');
+            element.textContent = 'ありがとう';
+            container.appendChild(element);
+        }
+
+        counter += amount;
+        document.querySelector('#counter').textContent = counter;
+    }
+})();
+    </script>
+
+</div></body>
+</html>
diff --git a/test/data/html/test-document3.html b/test/data/html/test-document3.html
new file mode 100644
index 00000000..3e7d5236
--- /dev/null
+++ b/test/data/html/test-document3.html
@@ -0,0 +1,26 @@
+<!DOCTYPE html>
+<html>
+    <head>
+        <meta charset="UTF-8">
+        <meta name="viewport" content="width=device-width,initial-scale=1" />
+        <title>Yomichan Manual Performance Tests</title>
+        <link rel="icon" type="image/gif" href="data:image/gif;base64,R0lGODlhEAAQAKEBAAAAAP///////////yH5BAEKAAIALAAAAAAQABAAAAImFI6Zpt0B4YkS0TCpq07xbmEgcGVRUpLaI46ZG7ppalY0jDCwUAAAOw==" />
+        <link rel="stylesheet" href="test-stylesheet.css" />
+    </head>
+<body>
+
+    <h1>Yomichan Manual Performance Tests</h1>
+    <p class="description">Testing Yomichan performance with artificially demanding cases in a real browser</p>
+
+    <div class="test">
+        <div class="description">&lt;iframe&gt; element.</div>
+        <iframe src="test-document3-frame1.html" allowfullscreen="true" style="width: 100%; height: 200px; border: 1px solid #d8d8d8;"></iframe>
+    </div>
+
+    <div class="test">
+        <div class="description">&lt;iframe&gt; element containing an &lt;iframe&gt; element inside of an open shadow DOM.</div>
+        <iframe src="test-document3-frame2.html" allowfullscreen="true" style="width: 100%; height: 200px; border: 1px solid #d8d8d8;"></iframe>
+    </div>
+
+</body>
+</html>
diff --git a/test/data/html/test-dom-text-scanner.html b/test/data/html/test-dom-text-scanner.html
new file mode 100644
index 00000000..dc06eb64
--- /dev/null
+++ b/test/data/html/test-dom-text-scanner.html
@@ -0,0 +1,393 @@
+<!DOCTYPE html>
+<html>
+    <head>
+        <meta charset="UTF-8">
+        <meta name="viewport" content="width=device-width,initial-scale=1" />
+        <title>Yomichan DOMTextScanner Tests</title>
+        <link rel="icon" type="image/gif" href="data:image/gif;base64,R0lGODlhEAAQAKEBAAAAAP///////////yH5BAEKAAIALAAAAAAQABAAAAImFI6Zpt0B4YkS0TCpq07xbmEgcGVRUpLaI46ZG7ppalY0jDCwUAAAOw==" />
+        <link rel="stylesheet" href="test-stylesheet.css" />
+    </head>
+<body>
+
+    <h1>Yomichan DOMTextScanner Tests</h1>
+
+    <y-test
+        data-test-data='{
+            "node": "div:nth-of-type(1)",
+            "offset": 0,
+            "length": 15,
+            "expected": {
+                "node": "div:nth-of-type(2)>div::text",
+                "offset": 3,
+                "content": "小ぢん\nまり1\n小ぢん\nまり2"
+            }
+        }'
+    >
+        <y-description>Layout newlines expected due to entering and exiting display:block nodes.</y-description>
+<div><div>小ぢん</div>まり1</div>
+<div>小ぢん<div>まり2</div></div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 13,
+            "expected": {
+                "node": "div:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1\n小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>Layout newline expected due to sequential display:block elements.</y-description>
+<div>小ぢんまり1</div><div>小ぢんまり2</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 13,
+            "expected": {
+                "node": "div:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1\n小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>Layout newline expected due to sequential display:block elements separated by a newline.</y-description>
+<div>小ぢんまり1</div>
+<div>小ぢんまり2</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "span:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 12,
+            "expected": {
+                "node": "span:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>No newlines expected due to display:inline.</y-description>
+<span>小ぢんまり1</span><span>小ぢんまり2</span>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "span:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 13,
+            "expected": {
+                "node": "span:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1 小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>No newlines expected due to white-space:normal.</y-description>
+<span>小ぢんまり1</span>
+<span>小ぢんまり2</span>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "span:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 13,
+            "expected": {
+                "node": "span:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1\n小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>Newline expected due to white-space:pre.</y-description>
+<pre>
+<span>小ぢんまり1</span>
+<span>小ぢんまり2</span>
+</pre>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "span:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 12,
+            "expected": {
+                "node": "span:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>No newlines expected due to display:inline-block. Actual layout flow cannot be determined by DOM/CSS alone.</y-description>
+<span style="display: inline-block;">小ぢんまり1</span><span style="display: inline-block;">小ぢんまり2</span>
+    </y-test>
+
+    <y-test
+        style="position: relative;"
+        data-test-data='{
+            "node": "div:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 13,
+            "expected": {
+                "node": "div:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1\n小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>Single newline expected due to display:block layout.</y-description>
+<div>小ぢんまり1</div><div style="position: relative;">小ぢんまり2</div>
+    </y-test>
+
+    <y-test
+        style="position: relative; overflow: hidden;"
+        data-test-data='{
+            "node": "div:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 14,
+            "expected": {
+                "node": "div:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1\n\n小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>Two newlines expected due to position:absolute causing a significant layout change.</y-description>
+<div>小ぢんまり1</div><div style="position: absolute;">小ぢんまり2</div>
+    </y-test>
+
+    <y-test
+        style="position: relative; overflow: hidden;"
+        data-test-data='{
+            "node": "div:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 14,
+            "expected": {
+                "node": "div:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1\n\n小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>Two newlines expected due to position:fixed causing a significant layout change.</y-description>
+<div>小ぢんまり1</div><div style="position: fixed;">小ぢんまり2</div>
+    </y-test>
+
+    <y-test
+        style="position: relative;"
+        data-test-data='{
+            "node": "div:nth-of-type(1)::text",
+            "offset": 0,
+            "length": 14,
+            "expected": {
+                "node": "div:nth-of-type(2)::text",
+                "offset": 6,
+                "content": "小ぢんまり1\n\n小ぢんまり2"
+            }
+        }'
+    >
+        <y-description>Two newlines expected due to position:sticky being able to cause a significant layout change.</y-description>
+<div>小ぢんまり1</div><div style="position: sticky;">小ぢんまり2</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "rt",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::text",
+                "offset": 5,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Scanning text starting in an &lt;rt&gt; element. Should start scanning at the start of the &lt;ruby&gt; tag instead.</y-description>
+<div><ruby>小<rp>(</rp><rt>こ</rt><rp>)</rp></ruby>ぢんまり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip &lt;script&gt; content.</y-description>
+<div>小ぢん<script>/*comment*/</script>まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip &lt;style&gt; content.</y-description>
+<div>小ぢん<style>/*comment*/</style>まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip &lt;textarea&gt; content.</y-description>
+<div>小ぢん<textarea>textarea content</textarea>まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip &lt;input&gt; content.</y-description>
+<div>小ぢん<input value="content" />まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip &lt;button&gt; content.</y-description>
+<div>小ぢん<button>content</button>まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip content with font-size:0.</y-description>
+<div>小ぢん<span style="font-size: 0;">content</span>まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip content with opacity:0.</y-description>
+<div>小ぢん<span style="opacity: 0;">content</span>まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip content with visibility:hidden.</y-description>
+<div>小ぢん<span style="visibility: hidden;">content</span>まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip content with display:none.</y-description>
+<div>小ぢん<span style="display: none;">content</span>まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Don't skip content with user-select:none.</y-description>
+<div>小ぢ<span style="user-select: none;">ん</span>まり1</div>
+    </y-test>
+
+    <y-test
+        data-test-data='{
+            "node": "div",
+            "offset": 0,
+            "length": 6,
+            "expected": {
+                "node": "div::nth-text(2)",
+                "offset": 3,
+                "content": "小ぢんまり1"
+            }
+        }'
+    >
+        <y-description>Skip content with user-select:none <em>and</em> a transparent color.</y-description>
+<div>小ぢん<span style="user-select: none; color: rgba(0, 0, 0, 0);">content</span>まり1</div>
+    </y-test>
+
+</body>
+</html>
\ No newline at end of file
diff --git a/test/data/html/test-stylesheet.css b/test/data/html/test-stylesheet.css
index f63d2481..b4d2e255 100644
--- a/test/data/html/test-stylesheet.css
+++ b/test/data/html/test-stylesheet.css
@@ -19,7 +19,8 @@ p {
     margin: 0.33em 0;
 }
 
-h1+p {
+h1+p,
+h1+y-description {
     margin-top: -0.67em;
 }
 
@@ -28,7 +29,9 @@ a, a:visited {
     text-decoration: underline;
 }
 
-.test {
+.test,
+y-test {
+    display: block;
     background-color: #ffffff;
     margin: 1em 0;
     padding: 0.5em;
@@ -36,7 +39,8 @@ a, a:visited {
     border-radius: 4px;
 }
 
-.test:before {
+.test:before,
+y-test:before {
     content: "Test " counter(test-id);
     display: block;
     counter-increment: test-id;
@@ -45,7 +49,10 @@ a, a:visited {
     font-weight: bold;
 }
 
-.description {
+.description,
+y-description {
     color: #444444;
     font-style: italic;
+    display: block;
+    padding-bottom: 0.5em;
 }
diff --git a/test/test-database.js b/test/test-database.js
index d27f92e1..e8a4a343 100644
--- a/test/test-database.js
+++ b/test/test-database.js
@@ -92,13 +92,63 @@ class XMLHttpRequest {
     }
 }
 
+class Image {
+    constructor() {
+        this._src = '';
+        this._loadCallbacks = [];
+    }
+
+    get src() {
+        return this._src;
+    }
+
+    set src(value) {
+        this._src = value;
+        this._delayTriggerLoad();
+    }
+
+    get naturalWidth() {
+        return 100;
+    }
+
+    get naturalHeight() {
+        return 100;
+    }
+
+    addEventListener(eventName, callback) {
+        if (eventName === 'load') {
+            this._loadCallbacks.push(callback);
+        }
+    }
+
+    removeEventListener(eventName, callback) {
+        if (eventName === 'load') {
+            const index = this._loadCallbacks.indexOf(callback);
+            if (index >= 0) {
+                this._loadCallbacks.splice(index, 1);
+            }
+        }
+    }
+
+    async _delayTriggerLoad() {
+        await Promise.resolve();
+        for (const callback of this._loadCallbacks) {
+            callback();
+        }
+    }
+}
+
 
 const vm = new VM({
     chrome,
+    Image,
     XMLHttpRequest,
     indexedDB: global.indexedDB,
     IDBKeyRange: global.IDBKeyRange,
-    JSZip: yomichanTest.JSZip
+    JSZip: yomichanTest.JSZip,
+    addEventListener() {
+        // NOP
+    }
 });
 vm.context.window = vm.context;
 
@@ -106,6 +156,7 @@ vm.execute([
     'bg/js/json-schema.js',
     'bg/js/dictionary.js',
     'mixed/js/core.js',
+    'bg/js/media-utility.js',
     'bg/js/request.js',
     'bg/js/dictionary-importer.js',
     'bg/js/database.js'
@@ -182,10 +233,10 @@ async function testDatabase1() {
                 let progressEvent = false;
                 await database.deleteDictionary(
                     title,
+                    {rate: 1000},
                     () => {
                         progressEvent = true;
-                    },
-                    {rate: 1000}
+                    }
                 );
                 assert.ok(progressEvent);
 
@@ -216,10 +267,10 @@ async function testDatabase1() {
         const {result, errors} = await dictionaryImporter.import(
             database,
             testDictionarySource,
+            {prefixWildcardsSupported: true},
             () => {
                 progressEvent = true;
-            },
-            {prefixWildcardsSupported: true}
+            }
         );
         vm.assert.deepStrictEqual(errors, []);
         vm.assert.deepStrictEqual(result, expectedSummary);
@@ -235,8 +286,8 @@ async function testDatabase1() {
             true
         );
         vm.assert.deepStrictEqual(counts, {
-            counts: [{kanji: 2, kanjiMeta: 2, terms: 32, termMeta: 6, tagMeta: 14}],
-            total: {kanji: 2, kanjiMeta: 2, terms: 32, termMeta: 6, tagMeta: 14}
+            counts: [{kanji: 2, kanjiMeta: 2, terms: 33, termMeta: 12, tagMeta: 14}],
+            total: {kanji: 2, kanjiMeta: 2, terms: 33, termMeta: 12, tagMeta: 14}
         });
 
         // Test find* functions
@@ -626,9 +677,9 @@ async function testFindTermMetaBulk1(database, titles) {
                 }
             ],
             expectedResults: {
-                total: 1,
+                total: 3,
                 modes: [
-                    ['freq', 1]
+                    ['freq', 3]
                 ]
             }
         },
@@ -639,9 +690,9 @@ async function testFindTermMetaBulk1(database, titles) {
                 }
             ],
             expectedResults: {
-                total: 1,
+                total: 3,
                 modes: [
-                    ['freq', 1]
+                    ['freq', 3]
                 ]
             }
         },
@@ -652,9 +703,9 @@ async function testFindTermMetaBulk1(database, titles) {
                 }
             ],
             expectedResults: {
-                total: 3,
+                total: 5,
                 modes: [
-                    ['freq', 1],
+                    ['freq', 3],
                     ['pitch', 2]
                 ]
             }
@@ -857,7 +908,7 @@ async function testDatabase2() {
 
     // Error: not prepared
     await assert.rejects(async () => await database.purge());
-    await assert.rejects(async () => await database.deleteDictionary(title, () => {}, {}));
+    await assert.rejects(async () => await database.deleteDictionary(title, {}, () => {}));
     await assert.rejects(async () => await database.findTermsBulk(['?'], titles, null));
     await assert.rejects(async () => await database.findTermsExactBulk(['?'], ['?'], titles));
     await assert.rejects(async () => await database.findTermsBySequenceBulk([1], title));
@@ -868,17 +919,17 @@ async function testDatabase2() {
     await assert.rejects(async () => await database.findTagForTitle('tag', title));
     await assert.rejects(async () => await database.getDictionaryInfo());
     await assert.rejects(async () => await database.getDictionaryCounts(titles, true));
-    await assert.rejects(async () => await dictionaryImporter.import(database, testDictionarySource, () => {}, {}));
+    await assert.rejects(async () => await dictionaryImporter.import(database, testDictionarySource, {}, () => {}));
 
     await database.prepare();
 
     // Error: already prepared
     await assert.rejects(async () => await database.prepare());
 
-    await dictionaryImporter.import(database, testDictionarySource, () => {}, {});
+    await dictionaryImporter.import(database, testDictionarySource, {}, () => {});
 
     // Error: dictionary already imported
-    await assert.rejects(async () => await dictionaryImporter.import(database, testDictionarySource, () => {}, {}));
+    await assert.rejects(async () => await dictionaryImporter.import(database, testDictionarySource, {}, () => {}));
 
     await database.close();
 }
@@ -905,7 +956,7 @@ async function testDatabase3() {
 
         let error = null;
         try {
-            await dictionaryImporter.import(database, testDictionarySource, () => {}, {});
+            await dictionaryImporter.import(database, testDictionarySource, {}, () => {});
         } catch (e) {
             error = e;
         }
diff --git a/test/test-dom-text-scanner.js b/test/test-dom-text-scanner.js
new file mode 100644
index 00000000..7374ff87
--- /dev/null
+++ b/test/test-dom-text-scanner.js
@@ -0,0 +1,183 @@
+/*
+ * Copyright (C) 2020  Yomichan Authors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+const fs = require('fs');
+const path = require('path');
+const assert = require('assert');
+const {JSDOM} = require('jsdom');
+const {VM} = require('./yomichan-vm');
+
+
+function createJSDOM(fileName) {
+    const domSource = fs.readFileSync(fileName, {encoding: 'utf8'});
+    return new JSDOM(domSource);
+}
+
+function querySelectorTextNode(element, selector) {
+    let textIndex = -1;
+    const match = /::text$|::nth-text\((\d+)\)$/.exec(selector);
+    if (match !== null) {
+        textIndex = (match[1] ? parseInt(match[1], 10) - 1 : 0);
+        selector = selector.substring(0, selector.length - match[0].length);
+    }
+    const result = element.querySelector(selector);
+    if (textIndex < 0) {
+        return result;
+    }
+    for (let n = result.firstChild; n !== null; n = n.nextSibling) {
+        if (n.nodeType === n.constructor.TEXT_NODE) {
+            if (textIndex === 0) {
+                return n;
+            }
+            --textIndex;
+        }
+    }
+    return null;
+}
+
+
+function getComputedFontSizeInPixels(window, getComputedStyle, element) {
+    for (; element !== null; element = element.parentNode) {
+        if (element.nodeType === window.Node.ELEMENT_NODE) {
+            const fontSize = getComputedStyle(element).fontSize;
+            if (fontSize.endsWith('px')) {
+                const value = parseFloat(fontSize.substring(0, fontSize.length - 2));
+                return value;
+            }
+        }
+    }
+    const defaultFontSize = 14;
+    return defaultFontSize;
+}
+
+function createAbsoluteGetComputedStyle(window) {
+    // Wrapper to convert em units to px units
+    const getComputedStyleOld = window.getComputedStyle.bind(window);
+    return (element, ...args) => {
+        const style = getComputedStyleOld(element, ...args);
+        return new Proxy(style, {
+            get: (target, property) => {
+                let result = target[property];
+                if (typeof result === 'string') {
+                    result = result.replace(/([-+]?\d(?:\.\d)?(?:[eE][-+]?\d+)?)em/g, (g0, g1) => {
+                        const fontSize = getComputedFontSizeInPixels(window, getComputedStyleOld, element);
+                        return `${parseFloat(g1) * fontSize}px`;
+                    });
+                }
+                return result;
+            }
+        });
+    };
+}
+
+
+async function testDomTextScanner(dom, {DOMTextScanner}) {
+    const document = dom.window.document;
+    for (const testElement of document.querySelectorAll('y-test')) {
+        let testData = JSON.parse(testElement.dataset.testData);
+        if (!Array.isArray(testData)) {
+            testData = [testData];
+        }
+        for (const testDataItem of testData) {
+            let {
+                node,
+                offset,
+                length,
+                forcePreserveWhitespace,
+                generateLayoutContent,
+                reversible,
+                expected: {
+                    node: expectedNode,
+                    offset: expectedOffset,
+                    content: expectedContent,
+                    remainder: expectedRemainder
+                }
+            } = testDataItem;
+
+            node = querySelectorTextNode(testElement, node);
+            expectedNode = querySelectorTextNode(testElement, expectedNode);
+
+            // Standard test
+            {
+                const scanner = new DOMTextScanner(node, offset, forcePreserveWhitespace, generateLayoutContent);
+                scanner.seek(length);
+
+                const {node: actualNode1, offset: actualOffset1, content: actualContent1, remainder: actualRemainder1} = scanner;
+                assert.strictEqual(actualContent1, expectedContent);
+                assert.strictEqual(actualOffset1, expectedOffset);
+                assert.strictEqual(actualNode1, expectedNode);
+                assert.strictEqual(actualRemainder1, expectedRemainder || 0);
+            }
+
+            // Substring tests
+            for (let i = 1; i <= length; ++i) {
+                const scanner = new DOMTextScanner(node, offset, forcePreserveWhitespace, generateLayoutContent);
+                scanner.seek(length - i);
+
+                const {content: actualContent} = scanner;
+                assert.strictEqual(actualContent, expectedContent.substring(0, expectedContent.length - i));
+            }
+
+            if (reversible === false) { continue; }
+
+            // Reversed test
+            {
+                const scanner = new DOMTextScanner(expectedNode, expectedOffset, forcePreserveWhitespace, generateLayoutContent);
+                scanner.seek(-length);
+
+                const {content: actualContent} = scanner;
+                assert.strictEqual(actualContent, expectedContent);
+            }
+
+            // Reversed substring tests
+            for (let i = 1; i <= length; ++i) {
+                const scanner = new DOMTextScanner(expectedNode, expectedOffset, forcePreserveWhitespace, generateLayoutContent);
+                scanner.seek(-(length - i));
+
+                const {content: actualContent} = scanner;
+                assert.strictEqual(actualContent, expectedContent.substring(i));
+            }
+        }
+    }
+}
+
+
+async function testDocument1() {
+    const dom = createJSDOM(path.join(__dirname, 'data', 'html', 'test-dom-text-scanner.html'));
+    const window = dom.window;
+    try {
+        const {document, Node, Range} = window;
+
+        window.getComputedStyle = createAbsoluteGetComputedStyle(window);
+
+        const vm = new VM({document, window, Range, Node});
+        vm.execute('fg/js/dom-text-scanner.js');
+        const DOMTextScanner = vm.get('DOMTextScanner');
+
+        await testDomTextScanner(dom, {DOMTextScanner});
+    } finally {
+        window.close();
+    }
+}
+
+
+async function main() {
+    await testDocument1();
+}
+
+
+if (require.main === module) { main(); }
diff --git a/test/test-japanese.js b/test/test-japanese.js
index 87efdfad..39004128 100644
--- a/test/test-japanese.js
+++ b/test/test-japanese.js
@@ -22,8 +22,7 @@ const vm = new VM();
 vm.execute([
     'mixed/lib/wanakana.min.js',
     'mixed/js/japanese.js',
-    'bg/js/text-source-map.js',
-    'bg/js/japanese.js'
+    'bg/js/text-source-map.js'
 ]);
 const jp = vm.get('jp');
 const TextSourceMap = vm.get('TextSourceMap');
@@ -434,17 +433,17 @@ function testIsMoraPitchHigh() {
         [[2, 1], false],
         [[3, 1], false],
 
-        [[0, 2], true],
+        [[0, 2], false],
         [[1, 2], true],
         [[2, 2], false],
         [[3, 2], false],
 
-        [[0, 3], true],
+        [[0, 3], false],
         [[1, 3], true],
         [[2, 3], true],
         [[3, 3], false],
 
-        [[0, 4], true],
+        [[0, 4], false],
         [[1, 4], true],
         [[2, 4], true],
         [[3, 4], true]
diff --git a/test/test-object-property-accessor.js b/test/test-object-property-accessor.js
index 0773ba6e..1e694946 100644
--- a/test/test-object-property-accessor.js
+++ b/test/test-object-property-accessor.js
@@ -40,29 +40,30 @@ function createTestObject() {
 }
 
 
-function testGetProperty1() {
-    const object = createTestObject();
-    const accessor = new ObjectPropertyAccessor(object);
-
+function testGet1() {
     const data = [
-        [[], object],
-        [['0'], object['0']],
-        [['value1'], object.value1],
-        [['value1', 'value2'], object.value1.value2],
-        [['value1', 'value3'], object.value1.value3],
-        [['value1', 'value4'], object.value1.value4],
-        [['value5'], object.value5],
-        [['value5', 0], object.value5[0]],
-        [['value5', 1], object.value5[1]],
-        [['value5', 2], object.value5[2]]
+        [[], (object) => object],
+        [['0'], (object) => object['0']],
+        [['value1'], (object) => object.value1],
+        [['value1', 'value2'], (object) => object.value1.value2],
+        [['value1', 'value3'], (object) => object.value1.value3],
+        [['value1', 'value4'], (object) => object.value1.value4],
+        [['value5'], (object) => object.value5],
+        [['value5', 0], (object) => object.value5[0]],
+        [['value5', 1], (object) => object.value5[1]],
+        [['value5', 2], (object) => object.value5[2]]
     ];
 
-    for (const [pathArray, expected] of data) {
-        assert.strictEqual(accessor.getProperty(pathArray), expected);
+    for (const [pathArray, getExpected] of data) {
+        const object = createTestObject();
+        const accessor = new ObjectPropertyAccessor(object);
+        const expected = getExpected(object);
+
+        assert.strictEqual(accessor.get(pathArray), expected);
     }
 }
 
-function testGetProperty2() {
+function testGet2() {
     const object = createTestObject();
     const accessor = new ObjectPropertyAccessor(object);
 
@@ -89,15 +90,12 @@ function testGetProperty2() {
     ];
 
     for (const [pathArray, message] of data) {
-        assert.throws(() => accessor.getProperty(pathArray), {message});
+        assert.throws(() => accessor.get(pathArray), {message});
     }
 }
 
 
-function testSetProperty1() {
-    const object = createTestObject();
-    const accessor = new ObjectPropertyAccessor(object);
-
+function testSet1() {
     const testValue = {};
     const data = [
         ['0'],
@@ -112,17 +110,21 @@ function testSetProperty1() {
     ];
 
     for (const pathArray of data) {
-        accessor.setProperty(pathArray, testValue);
-        assert.strictEqual(accessor.getProperty(pathArray), testValue);
+        const object = createTestObject();
+        const accessor = new ObjectPropertyAccessor(object);
+
+        accessor.set(pathArray, testValue);
+        assert.strictEqual(accessor.get(pathArray), testValue);
     }
 }
 
-function testSetProperty2() {
+function testSet2() {
     const object = createTestObject();
     const accessor = new ObjectPropertyAccessor(object);
 
     const testValue = {};
     const data = [
+        [[], 'Invalid path'],
         [[0], 'Invalid path: [0]'],
         [['0', 'invalid'], 'Invalid path: ["0"].invalid'],
         [['value1', 'value2', 0], 'Invalid path: value1.value2[0]'],
@@ -137,7 +139,127 @@ function testSetProperty2() {
     ];
 
     for (const [pathArray, message] of data) {
-        assert.throws(() => accessor.setProperty(pathArray, testValue), {message});
+        assert.throws(() => accessor.set(pathArray, testValue), {message});
+    }
+}
+
+
+function testDelete1() {
+    const hasOwn = (object, property) => Object.prototype.hasOwnProperty.call(object, property);
+
+    const data = [
+        [['0'], (object) => !hasOwn(object, '0')],
+        [['value1', 'value2'], (object) => !hasOwn(object.value1, 'value2')],
+        [['value1', 'value3'], (object) => !hasOwn(object.value1, 'value3')],
+        [['value1', 'value4'], (object) => !hasOwn(object.value1, 'value4')],
+        [['value1'], (object) => !hasOwn(object, 'value1')],
+        [['value5'], (object) => !hasOwn(object, 'value5')]
+    ];
+
+    for (const [pathArray, validate] of data) {
+        const object = createTestObject();
+        const accessor = new ObjectPropertyAccessor(object);
+
+        accessor.delete(pathArray);
+        assert.ok(validate(object));
+    }
+}
+
+function testDelete2() {
+    const data = [
+        [[], 'Invalid path'],
+        [[0], 'Invalid path: [0]'],
+        [['0', 'invalid'], 'Invalid path: ["0"].invalid'],
+        [['value1', 'value2', 0], 'Invalid path: value1.value2[0]'],
+        [['value1', 'value3', 'invalid'], 'Invalid path: value1.value3.invalid'],
+        [['value1', 'value4', 'invalid'], 'Invalid path: value1.value4.invalid'],
+        [['value1', 'value4', 0], 'Invalid path: value1.value4[0]'],
+        [['value5', 1, 'invalid'], 'Invalid path: value5[1].invalid'],
+        [['value5', 2, 'invalid'], 'Invalid path: value5[2].invalid'],
+        [['value5', 2, 0], 'Invalid path: value5[2][0]'],
+        [['value5', 2, 0, 'invalid'], 'Invalid path: value5[2][0]'],
+        [['value5', 2.5], 'Invalid index'],
+        [['value5', 0], 'Invalid type'],
+        [['value5', 1], 'Invalid type'],
+        [['value5', 2], 'Invalid type']
+    ];
+
+    for (const [pathArray, message] of data) {
+        const object = createTestObject();
+        const accessor = new ObjectPropertyAccessor(object);
+
+        assert.throws(() => accessor.delete(pathArray), {message});
+    }
+}
+
+
+function testSwap1() {
+    const data = [
+        [['0'], true],
+        [['value1', 'value2'], true],
+        [['value1', 'value3'], true],
+        [['value1', 'value4'], true],
+        [['value1'], false],
+        [['value5', 0], true],
+        [['value5', 1], true],
+        [['value5', 2], true],
+        [['value5'], false]
+    ];
+
+    for (const [pathArray1, compareValues1] of data) {
+        for (const [pathArray2, compareValues2] of data) {
+            const object = createTestObject();
+            const accessor = new ObjectPropertyAccessor(object);
+
+            const value1a = accessor.get(pathArray1);
+            const value2a = accessor.get(pathArray2);
+
+            accessor.swap(pathArray1, pathArray2);
+
+            if (!compareValues1 || !compareValues2) { continue; }
+
+            const value1b = accessor.get(pathArray1);
+            const value2b = accessor.get(pathArray2);
+
+            assert.deepStrictEqual(value1a, value2b);
+            assert.deepStrictEqual(value2a, value1b);
+        }
+    }
+}
+
+function testSwap2() {
+    const data = [
+        [[], [], false, 'Invalid path 1'],
+        [['0'], [], false, 'Invalid path 2'],
+        [[], ['0'], false, 'Invalid path 1'],
+        [[0], ['0'], false, 'Invalid path 1: [0]'],
+        [['0'], [0], false, 'Invalid path 2: [0]']
+    ];
+
+    for (const [pathArray1, pathArray2, checkRevert, message] of data) {
+        const object = createTestObject();
+        const accessor = new ObjectPropertyAccessor(object);
+
+        let value1a;
+        let value2a;
+        if (checkRevert) {
+            try {
+                value1a = accessor.get(pathArray1);
+                value2a = accessor.get(pathArray2);
+            } catch (e) {
+                // NOP
+            }
+        }
+
+        assert.throws(() => accessor.swap(pathArray1, pathArray2), {message});
+
+        if (!checkRevert) { continue; }
+
+        const value1b = accessor.get(pathArray1);
+        const value2b = accessor.get(pathArray2);
+
+        assert.deepStrictEqual(value1a, value1b);
+        assert.deepStrictEqual(value2a, value2b);
     }
 }
 
@@ -272,10 +394,14 @@ function testIsValidPropertyType() {
 
 
 function main() {
-    testGetProperty1();
-    testGetProperty2();
-    testSetProperty1();
-    testSetProperty2();
+    testGet1();
+    testGet2();
+    testSet1();
+    testSet2();
+    testDelete1();
+    testDelete2();
+    testSwap1();
+    testSwap2();
     testGetPathString1();
     testGetPathString2();
     testGetPathArray1();
diff --git a/test/yomichan-test.js b/test/yomichan-test.js
index 3351ecdf..b4f5ac7c 100644
--- a/test/yomichan-test.js
+++ b/test/yomichan-test.js
@@ -38,12 +38,17 @@ function createTestDictionaryArchive(dictionary, dictionaryName) {
     const archive = new (getJSZip())();
 
     for (const fileName of fileNames) {
-        const source = fs.readFileSync(path.join(dictionaryDirectory, fileName), {encoding: 'utf8'});
-        const json = JSON.parse(source);
-        if (fileName === 'index.json' && typeof dictionaryName === 'string') {
-            json.title = dictionaryName;
+        if (/\.json$/.test(fileName)) {
+            const content = fs.readFileSync(path.join(dictionaryDirectory, fileName), {encoding: 'utf8'});
+            const json = JSON.parse(content);
+            if (fileName === 'index.json' && typeof dictionaryName === 'string') {
+                json.title = dictionaryName;
+            }
+            archive.file(fileName, JSON.stringify(json, null, 0));
+        } else {
+            const content = fs.readFileSync(path.join(dictionaryDirectory, fileName), {encoding: null});
+            archive.file(fileName, content);
         }
-        archive.file(fileName, JSON.stringify(json, null, 0));
     }
 
     return archive;