Fix PHP numeric deserializer keys

CHANGELOG.md

@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- PHP: generated deserializers with numeric property names now satisfy static return-type analysis. [#7830](https://github.com/microsoft/kiota/issues/7830)
 - golang: generated code now always uses LF line endings, so `gofmt` no longer reports formatting differences when generating on Windows.
 - golang: make sure all generated code adheres to golangs coding standards
 - Fixed non-deterministic model class descriptions when a component schema is referenced from multiple properties with differing reference-level descriptions. [#7927](https://github.com/microsoft/kiota/issues/7927)

src/Kiota.Builder/Writers/Php/CodeMethodWriter.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Linq;
 using Kiota.Builder.CodeDOM;
 using Kiota.Builder.Extensions;
@@ -680,23 +681,31 @@ private void WriteDeserializerBody(CodeClass parentClass, LanguageWriter writer,
     }
     private void WriteDeserializerBodyForInheritedModel(CodeMethod method, CodeClass parentClass, LanguageWriter writer, bool extendsModelClass = false)
     {
-        var codeProperties = parentClass.GetPropertiesOfKind(CodePropertyKind.Custom).ToArray();
+        var codeProperties = parentClass.GetPropertiesOfKind(CodePropertyKind.Custom)
+            .Where(static x => !x.ExistsInBaseType && x.Setter != null)
+            .OrderBy(static x => x.Name)
+            .ToArray();
+        var hasNumericPropertyName = codeProperties.Any(static x => IsNumericArrayKey(x.WireName));
         writer.WriteLine("$o = $this;");
+        if (hasNumericPropertyName)
+            writer.WriteLine("/** @var array<string, callable(ParseNode): void> $deserializers */");
         writer.WriteLines(
-            $"return {((extendsModelClass) ? $"array_merge(parent::{method.Name.ToFirstCharacterLowerCase()}(), [" : " [")}");
+            $"{(hasNumericPropertyName ? "$deserializers =" : "return")} {((extendsModelClass) ? $"array_merge(parent::{method.Name.ToFirstCharacterLowerCase()}(), [" : " [")}");
         writer.IncreaseIndent();
         if (codeProperties.Length != 0)
-        {
             codeProperties
-                .Where(static x => !x.ExistsInBaseType && x.Setter != null)
-                .OrderBy(static x => x.Name)
                 .ToList()
                 .ForEach(x => WriteDeserializerPropertyCallback(x, method, writer));
-        }
         writer.DecreaseIndent();
         writer.WriteLine(extendsModelClass ? "]);" : "];");
+        if (hasNumericPropertyName)
+            writer.WriteLine("return $deserializers;");
     }
 
+    private static bool IsNumericArrayKey(string key) =>
+        long.TryParse(key, NumberStyles.Integer, CultureInfo.InvariantCulture, out var value) &&
+        value.ToString(CultureInfo.InvariantCulture).Equals(key, StringComparison.Ordinal);
+
     private void WriteDeserializerPropertyCallback(CodeProperty property, CodeMethod method, LanguageWriter writer)
     {
         if (property.Type.CollectionKind != CodeTypeBase.CodeTypeCollectionKind.None

tests/Kiota.Builder.Tests/Writers/Php/CodeMethodWriterTests.cs

@@ -962,6 +962,14 @@ public async Task EscapesIndexerPathParameterNameAsync()
             "'dOB' => fn(ParseNode $n) => $o->setDOB($n->getDateTimeValue()),"
         },
         new object[]
+        {
+            new CodeProperty { Name = "fiveHundred", Type = new CodeType { Name = "int32" }, Access = AccessModifier.Private, Kind = CodePropertyKind.Custom, SerializationName = "500" },
+            "/** @var array<string, callable(ParseNode): void> $deserializers */",
+            "$deserializers =",
+            "'500' => fn(ParseNode $n) => $o->setFiveHundred($n->getIntegerValue()),",
+            "return $deserializers;"
+        },
+        new object[]
         {
             new CodeProperty { Name = "story", Type = new CodeType { Name = "binary" }, Access = AccessModifier.Private, Kind = CodePropertyKind.Custom },
             "'story' => fn(ParseNode $n) => $o->setStory($n->getBinaryContent()),"