Unescape query parameter name (#33401)

Author: campersau

src/Http/Http/src/Features/QueryFeature.cs

@@ -143,7 +143,9 @@ public IQueryCollection Query
                 {
                     if (!querySegment.IsEmpty)
                     {
-                        accumulator.Append(querySegment);
+                        var name = SpanHelper.ReplacePlusWithSpace(querySegment);
+
+                        accumulator.Append(Uri.UnescapeDataString(name));
                     }
                 }
 

src/Http/Http/test/Features/QueryFeatureTests.cs

@@ -150,5 +150,75 @@ public void ParseEmptyOrNullQueryWorks(string queryString)
 
             Assert.Empty(queryCollection);
         }
+
+        [Fact]
+        public void ParseQueryWithEncodedKeyWorks()
+        {
+            var features = new FeatureCollection();
+            features[typeof(IHttpRequestFeature)] = new HttpRequestFeature { QueryString = "?fields+%5BtodoItems%5D" };
+
+            var provider = new QueryFeature(features);
+
+            var queryCollection = provider.Query;
+
+            Assert.Single(queryCollection);
+            Assert.Equal("", queryCollection["fields [todoItems]"].FirstOrDefault());
+        }
+
+        [Fact]
+        public void ParseQueryWithEncodedValueWorks()
+        {
+            var features = new FeatureCollection();
+            features[typeof(IHttpRequestFeature)] = new HttpRequestFeature { QueryString = "?=fields+%5BtodoItems%5D" };
+
+            var provider = new QueryFeature(features);
+
+            var queryCollection = provider.Query;
+
+            Assert.Single(queryCollection);
+            Assert.Equal("fields [todoItems]", queryCollection[""].FirstOrDefault());
+        }
+
+        [Fact]
+        public void ParseQueryWithEncodedKeyEmptyValueWorks()
+        {
+            var features = new FeatureCollection();
+            features[typeof(IHttpRequestFeature)] = new HttpRequestFeature { QueryString = "?fields+%5BtodoItems%5D=" };
+
+            var provider = new QueryFeature(features);
+
+            var queryCollection = provider.Query;
+
+            Assert.Single(queryCollection);
+            Assert.Equal("", queryCollection["fields [todoItems]"].FirstOrDefault());
+        }
+
+        [Fact]
+        public void ParseQueryWithEncodedKeyEncodedValueWorks()
+        {
+            var features = new FeatureCollection();
+            features[typeof(IHttpRequestFeature)] = new HttpRequestFeature { QueryString = "?fields+%5BtodoItems%5D=%5B+1+%5D" };
+
+            var provider = new QueryFeature(features);
+
+            var queryCollection = provider.Query;
+
+            Assert.Single(queryCollection);
+            Assert.Equal("[ 1 ]", queryCollection["fields [todoItems]"].FirstOrDefault());
+        }
+
+        [Fact]
+        public void ParseQueryWithEncodedKeyEncodedValuesWorks()
+        {
+            var features = new FeatureCollection();
+            features[typeof(IHttpRequestFeature)] = new HttpRequestFeature { QueryString = "?fields+%5BtodoItems%5D=%5B+1+%5D&fields+%5BtodoItems%5D=%5B+2+%5D" };
+
+            var provider = new QueryFeature(features);
+
+            var queryCollection = provider.Query;
+
+            Assert.Single(queryCollection);
+            Assert.Equal(new[] { "[ 1 ]", "[ 2 ]" }, queryCollection["fields [todoItems]"]);
+        }
     }
 }

src/Http/WebUtilities/src/QueryHelpers.cs

@@ -218,7 +218,10 @@ public static Dictionary<string, StringValues> ParseQuery(string? queryString)
                 {
                     if (delimiterIndex > scanIndex)
                     {
-                        accumulator.Append(queryString.Substring(scanIndex, delimiterIndex - scanIndex), string.Empty);
+                        string name = queryString.Substring(scanIndex, delimiterIndex - scanIndex);
+                        accumulator.Append(
+                            Uri.UnescapeDataString(name.Replace('+', ' ')),
+                            string.Empty);
                     }
                 }
                 scanIndex = delimiterIndex + 1;

src/Http/WebUtilities/test/QueryHelpersTests.cs

@@ -55,6 +55,46 @@ public void ParseQueryWithEmptyKeyWorks()
             Assert.Equal(new[] { "value1", "" }, collection[""]);
         }
 
+        [Fact]
+        public void ParseQueryWithEncodedKeyWorks()
+        {
+            var collection = QueryHelpers.ParseQuery("?fields+%5BtodoItems%5D");
+            Assert.Single(collection);
+            Assert.Equal("", collection["fields [todoItems]"].FirstOrDefault());
+        }
+
+        [Fact]
+        public void ParseQueryWithEncodedValueWorks()
+        {
+            var collection = QueryHelpers.ParseQuery("?=fields+%5BtodoItems%5D");
+            Assert.Single(collection);
+            Assert.Equal("fields [todoItems]", collection[""].FirstOrDefault());
+        }
+
+        [Fact]
+        public void ParseQueryWithEncodedKeyEmptyValueWorks()
+        {
+            var collection = QueryHelpers.ParseQuery("?fields+%5BtodoItems%5D=");
+            Assert.Single(collection);
+            Assert.Equal("", collection["fields [todoItems]"].FirstOrDefault());
+        }
+
+        [Fact]
+        public void ParseQueryWithEncodedKeyEncodedValueWorks()
+        {
+            var collection = QueryHelpers.ParseQuery("?fields+%5BtodoItems%5D=%5B+1+%5D");
+            Assert.Single(collection);
+            Assert.Equal("[ 1 ]", collection["fields [todoItems]"].FirstOrDefault());
+        }
+
+        [Fact]
+        public void ParseQueryWithEncodedKeyEncodedValuesWorks()
+        {
+            var collection = QueryHelpers.ParseQuery("?fields+%5BtodoItems%5D=%5B+1+%5D&fields+%5BtodoItems%5D=%5B+2+%5D");
+            Assert.Single(collection);
+            Assert.Equal(new[] { "[ 1 ]", "[ 2 ]" }, collection["fields [todoItems]"]);
+        }
+
         [Theory]
         [InlineData("?")]
         [InlineData("")]