From a31734014d6c58f1b8f68708689c7453356f6c7c Mon Sep 17 00:00:00 2001
From: Andrew H <369769+andrew-from-toronto@users.noreply.github.com>
Date: Mon, 29 Apr 2024 20:06:24 -0400
Subject: [PATCH] Fix #2693 PageCount doesn't work if the query gets
 constructed with page number as the first query parameter  (#2911)

Fix #2693

Co-authored-by: Keegan Campbell <me@kfcampbell.com>
---
 Octokit.Tests/Http/PaginationTests.cs | 46 +++++++++++++++++++++++++++
 Octokit/Helpers/Pagination.cs         | 11 +++++--
 2 files changed, 54 insertions(+), 3 deletions(-)
 create mode 100644 Octokit.Tests/Http/PaginationTests.cs

diff --git a/Octokit.Tests/Http/PaginationTests.cs b/Octokit.Tests/Http/PaginationTests.cs
new file mode 100644
index 00000000..94657d2b
--- /dev/null
+++ b/Octokit.Tests/Http/PaginationTests.cs
@@ -0,0 +1,46 @@
+using System;
+using Octokit.Models.Request.Enterprise;
+using Xunit;
+
+namespace Octokit.Tests.Http
+{
+    public class PaginationTests
+    {
+        public class TheShouldContinueMethod
+        {
+            [Fact]
+            public void HandlesMissingUri()
+            {
+                var result = Pagination.ShouldContinue(null, null);
+                Assert.False(result);
+            }
+            
+            [Fact]
+            public void HandlesIsDone()
+            {
+                var uri = new Uri("http://example.com");
+                var options = new ApiOptionsExtended { IsDone = true };
+                var result = Pagination.ShouldContinue(uri, options);
+                Assert.False(result);
+            }
+            
+            [Fact]
+            public void HandlesPageCountPageFirstParam()
+            {
+                var uri = new Uri("http://example.com?page=2");
+                var options = new ApiOptions { StartPage = 1, PageCount = 1 };
+                var result = Pagination.ShouldContinue(uri, options);
+                Assert.False(result);
+            }
+            
+            [Fact]
+            public void HandlesPageCountPageNotFirstParam()
+            {
+                var uri = new Uri("http://example.com?page_size=100&page=2");
+                var options = new ApiOptions { StartPage = 1, PageCount = 1 };
+                var result = Pagination.ShouldContinue(uri, options);
+                Assert.False(result);
+            }
+        }
+    }
+}
diff --git a/Octokit/Helpers/Pagination.cs b/Octokit/Helpers/Pagination.cs
index fbd6bfe5..01b1196f 100644
--- a/Octokit/Helpers/Pagination.cs
+++ b/Octokit/Helpers/Pagination.cs
@@ -41,8 +41,7 @@ namespace Octokit
             {
                 var allValues = ToQueryStringDictionary(uri);
 
-                string pageValue;
-                if (allValues.TryGetValue("page", out pageValue))
+                if (allValues.TryGetValue("page", out var pageValue))
                 {
                     var startPage = options.StartPage ?? 1;
                     var pageCount = options.PageCount.Value;
@@ -61,8 +60,14 @@ namespace Octokit
         static Dictionary<string, string> ToQueryStringDictionary(Uri uri)
         {
             return uri.Query.Split('&')
-                .Select(keyValue =>
+                .Select((keyValue, i) =>
                 {
+                    if (i == 0)
+                    {
+                        // Trim the leading '?' character from the first key-value pair
+                        keyValue = keyValue.Substring(1);
+                    }
+                    
                     var indexOf = keyValue.IndexOf('=');
                     if (indexOf > 0)
                     {