hardkoded · kblok · Nov 3, 2025 · Oct 31, 2025
diff --git a/lib/CLAUDE.md b/lib/CLAUDE.md
@@ -392,15 +392,20 @@ Test directory structure demonstrates comprehensive coverage:
 When running tests, always build first and then use the `--no-build` flag to avoid rebuilding during test execution. This provides faster and more reliable test runs:
 Always be explicit with the browser and protocol you want to test using ENV variables BROWSER=FIREFOX|CHROME and PROTOCOL=bidi|cdp
 
+**IMPORTANT: Chrome should ALWAYS use CDP protocol. Firefox can use either CDP or BiDi.**
+
 ```bash
-# Build the test project first
+# Build the test project first with Firefox and BiDi
 BROWSER=FIREFOX PROTOCOL=bidi dotnet build PuppeteerSharp.Tests/PuppeteerSharp.Tests.csproj
 
 # Then run tests with --no-build flag
-BROWSER=CHROME PROTOCOL=bidi dotnet test PuppeteerSharp.Tests/PuppeteerSharp.Tests.csproj --filter "FullyQualifiedName~TestName" --no-build -- NUnit.TestOutputXml=TestResults
+BROWSER=FIREFOX PROTOCOL=bidi dotnet test PuppeteerSharp.Tests/PuppeteerSharp.Tests.csproj --filter "FullyQualifiedName~TestName" --no-build -- NUnit.TestOutputXml=TestResults
+
+# Chrome should ALWAYS use CDP protocol
+BROWSER=CHROME PROTOCOL=cdp dotnet build PuppeteerSharp.Tests/PuppeteerSharp.Tests.csproj && BROWSER=CHROME PROTOCOL=cdp dotnet test PuppeteerSharp.Tests/PuppeteerSharp.Tests.csproj --filter "FullyQualifiedName~TestName" --no-build -- NUnit.TestOutputXml=TestResults
 
-# Can also chain them together
-BROWSER=CHROME PROTOCOL=cdp dotnet build PuppeteerSharp.Tests/PuppeteerSharp.Tests.csproj && dotnet test PuppeteerSharp.Tests/PuppeteerSharp.Tests.csproj --filter "FullyQualifiedName~TestName" --no-build -- NUnit.TestOutputXml=TestResults
+# Firefox should ALWAYS use bidi protocol
+BROWSER=FIREFOX PROTOCOL=bidi dotnet build PuppeteerSharp.Tests/PuppeteerSharp.Tests.csproj && BROWSER=FIREFOX PROTOCOL=cdp dotnet test PuppeteerSharp.Tests/PuppeteerSharp.Tests.csproj --filter "FullyQualifiedName~TestName" --no-build -- NUnit.TestOutputXml=TestResults
 ```
 
 You can switch between CDP and Bidi by changing the PuppeteerTestAttribute.IsCdp property.

diff --git a/lib/PuppeteerSharp.Nunit/TestExpectations/TestExpectations.local.json b/lib/PuppeteerSharp.Nunit/TestExpectations/TestExpectations.local.json
@@ -1035,21 +1035,6 @@
       "FAIL"
     ]
   },
-  {
-    "comment": "This is part of organizing the webdriver bidi implementation, We will remove it one by one",
-    "testIdPattern": "[page.spec] *Page.select*",
-    "platforms": [
-      "darwin",
-      "linux",
-      "win32"
-    ],
-    "parameters": [
-      "webDriverBiDi"
-    ],
-    "expectations": [
-      "FAIL"
-    ]
-  },
   {
     "comment": "This is part of organizing the webdriver bidi implementation, We will remove it one by one",
     "testIdPattern": "[page.spec] *Page.setBypassCSP*",

diff --git a/lib/PuppeteerSharp.TestServer/wwwroot/input/select.html b/lib/PuppeteerSharp.TestServer/wwwroot/input/select.html
@@ -5,6 +5,7 @@
   </head>
   <body>
     <select>
+      <option value="">Empty</option>
       <option value="black">Black</option>
       <option value="blue">Blue</option>
       <option value="brown">Brown</option>

diff --git a/lib/PuppeteerSharp.Tests/PageTests/SelectTests.cs b/lib/PuppeteerSharp.Tests/PageTests/SelectTests.cs
@@ -117,8 +117,8 @@ public async Task ShouldDeselectAllOptionsWhenPassedNoValuesForASelectWithoutMul
             await Page.GoToAsync(TestConstants.ServerUrl + "/input/select.html");
             await Page.SelectAsync("select", "blue", "black", "magenta");
             await Page.SelectAsync("select");
-            Assert.That(await Page.QuerySelectorAsync("select").EvaluateFunctionAsync<bool>(
-                "select => Array.from(select.options).every(option => !option.selected)"), Is.True);
+            Assert.That(await Page.QuerySelectorAsync("select").EvaluateFunctionAsync<string>(
+                "select => Array.from(select.options).filter(option => option.selected)[0].value"), Is.EqualTo(""));
         }
     }
 }
diff --git a/lib/PuppeteerSharp/Bidi/BidiRealm.cs b/lib/PuppeteerSharp/Bidi/BidiRealm.cs
@@ -23,7 +23,6 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
-using System.Data;
 using System.Globalization;
 using System.Linq;
 using System.Numerics;
@@ -214,7 +213,7 @@ private async Task<EvaluateResultSuccess> EvaluateAsync(bool returnByValue, bool
         if (result.ResultType == EvaluateResultType.Exception)
         {
             // TODO: Improve text details
-            throw new EvaluateException(((EvaluateResultException)result).ExceptionDetails.Text);
+            throw new EvaluationFailedException(((EvaluateResultException)result).ExceptionDetails.Text);
         }
 
         return result as EvaluateResultSuccess;

diff --git a/lib/PuppeteerSharp/ElementHandle.cs b/lib/PuppeteerSharp/ElementHandle.cs
@@ -472,24 +472,53 @@ public Task<bool> IsIntersectingViewportAsync(decimal threshold)
 
         /// <inheritdoc/>
         public Task<string[]> SelectAsync(params string[] values)
-            => BindIsolatedHandleAsync<string[], ElementHandle>(handle => handle.EvaluateFunctionAsync<string[]>(
-                @"(element, values) =>
-                    {
-                        if (element.nodeName.toLowerCase() !== 'select')
-                            throw new Error('Element is not a <select> element.');
-
-                        const options = Array.from(element.options);
-                        element.value = undefined;
-                        for (const option of options) {
-                            option.selected = values.includes(option.value);
-                            if (option.selected && !element.multiple)
+        {
+            if (values == null)
+            {
+                throw new ArgumentNullException(nameof(values));
+            }
+
+            foreach (var value in values)
+            {
+                if (value == null)
+                {
+                    throw new ArgumentException($"Values must be strings. Found value \"null\" of type \"null\"");
+                }
+            }
+
+            return BindIsolatedHandleAsync<string[], ElementHandle>(handle => handle.EvaluateFunctionAsync<string[]>(
+                @"(element, vals) => {
+                    const values = new Set(vals);
+                    if (!(element instanceof HTMLSelectElement)) {
+                        throw new Error('Element is not a <select> element.');
+                    }
+
+                    const selectedValues = new Set();
+                    if (!element.multiple) {
+                        for (const option of element.options) {
+                            option.selected = false;
+                        }
+                        for (const option of element.options) {
+                            if (values.has(option.value)) {
+                                option.selected = true;
+                                selectedValues.add(option.value);
                                 break;
+                            }
                         }
-                        element.dispatchEvent(new Event('input', { 'bubbles': true }));
-                        element.dispatchEvent(new Event('change', { 'bubbles': true }));
-                        return options.filter(option => option.selected).map(option => option.value);
-                    }",
+                    } else {
+                        for (const option of element.options) {
+                            option.selected = values.has(option.value);
+                            if (option.selected) {
+                                selectedValues.add(option.value);
+                            }
+                        }
+                    }
+                    element.dispatchEvent(new Event('input', { bubbles: true }));
+                    element.dispatchEvent(new Event('change', { bubbles: true }));
+                    return [...selectedValues.values()];
+                }",
                 new object[] { values }));
+        }
 
         /// <inheritdoc/>
         public Task<DragData> DragAsync(decimal x, decimal y)