Increase namespace/type-name shortening threshold from 64 to 200

.github/workflows/surface-area-tests.yml

@@ -68,14 +68,18 @@ jobs:
         shell: pwsh
         timeout-minutes: 30
         run: |
-          $patchPath = Join-Path -Path (Get-Location) -ChildPath "${{ matrix.language }}-dom-export.patch"
+          $patchFileName = "${{ matrix.language }}-dom-export.patch"
+          $patchPath = Join-Path -Path (Get-Location) -ChildPath $patchFileName
           ./it/compare-dom-export.ps1 `
             -descriptionUrl "${{ matrix.description }}" `
             -language "${{ matrix.language }}" `
             -patchPath $patchPath `
             -baselineVersion "${{ github.event.inputs.baselineVersion }}"
           $hasPatch = (Test-Path $patchPath) -and ((Get-Item $patchPath).Length -gt 0)
-          Write-Output "patchFilePath=$patchPath" >> $Env:GITHUB_OUTPUT
+          # The diff tool runs as a Docker container action with the repository mounted at
+          # /github/workspace, so it must receive a workspace-relative path. Passing the
+          # absolute host path fails inside the container with a DirectoryNotFoundException.
+          Write-Output "patchFilePath=$patchFileName" >> $Env:GITHUB_OUTPUT
           Write-Output "hasPatch=$($hasPatch.ToString().ToLowerInvariant())" >> $Env:GITHUB_OUTPUT
 
       - name: Analyze DOM export diff for breaking changes

CHANGELOG.md

@@ -13,6 +13,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- Reduced the aggressiveness of namespace segment and type name shortening by raising the length threshold to 200 characters, so only names longer than 200 characters are truncated (to a 191-character prefix plus an underscore and 8-character hash). The threshold stays well below the 255 file-system per-component limit to leave room for extensions and language-specific suffixes appended by path segmenters and compilers (e.g. Java nested-class `.class` files and the extra underscores Python adds when converting names to snake_case).
+
 ## [1.34.0] - 2026-07-08
 
 ### Added

src/Kiota.Builder/Extensions/StringExtensions.cs

@@ -75,14 +75,18 @@ public static string ShortenFileName(this string name, int length = 251) =>
         (!string.IsNullOrEmpty(name) && name.Length > length) ? HashString(name).ToLowerInvariant() : name;
 #pragma warning restore CA1308
 
-    private const int DefaultMaxNameSegmentLength = 64;
+    // 200 keeps the shortened name well below the 255 file-system per-component limit (NAME_MAX),
+    // leaving room for extensions and language-specific suffixes that path segmenters and compilers
+    // append (e.g. ".java" plus nested-class suffixes like "$GetQueryParameters.class", or the extra
+    // underscores Python introduces when converting names to snake_case file names).
+    private const int DefaultMaxNameSegmentLength = 200;
     private const int HashSuffixLength = 8;
     /// <summary>
     /// Shortens a name segment to the specified maximum length by truncating and appending a short hash suffix.
     /// Preserves human readability by keeping the first part of the original name.
     /// </summary>
     /// <param name="name">The name to potentially shorten</param>
-    /// <param name="maxLength">The maximum allowed length. Default is 64.</param>
+    /// <param name="maxLength">The maximum allowed length. Default is 200.</param>
     /// <returns>The original name if within limits, or a truncated name with hash suffix for uniqueness</returns>
     public static string ShortenNameSegment(this string name, int maxLength = DefaultMaxNameSegmentLength)
     {

src/Kiota.Builder/Refiners/CommonLanguageRefiner.cs

@@ -1635,7 +1635,7 @@ protected static void DeduplicateErrorMappings(CodeElement codeElement)
     /// that map only namespaces to directories and group types into barrel files, where renaming types would
     /// break downstream name-based generation without any file-system benefit.
     /// </param>
-    protected static void ShortenOversizedNamespaceSegments(CodeElement currentElement, int maxSegmentLength = 64, bool shortenTypeNames = true)
+    protected static void ShortenOversizedNamespaceSegments(CodeElement currentElement, int maxSegmentLength = 200, bool shortenTypeNames = true)
     {
         if (currentElement is CodeNamespace codeNamespace && !string.IsNullOrEmpty(codeNamespace.Name))
         {

tests/Kiota.Builder.Tests/Extensions/StringExtensionsTests.cs

@@ -1,4 +1,6 @@
-using Kiota.Builder.Extensions;
+using System.Linq;
+
+using Kiota.Builder.Extensions;
 
 using Xunit;
 
@@ -140,32 +142,32 @@ public void ShortenNameSegmentReturnsOriginalWhenUnderLimit()
     [Fact]
     public void ShortenNameSegmentReturnsOriginalAtExactLimit()
     {
-        var name = new string('a', 64);
+        var name = new string('a', 200);
         Assert.Equal(name, name.ShortenNameSegment());
     }
     [Fact]
     public void ShortenNameSegmentTruncatesAndAppendsHashWhenOverLimit()
     {
-        var longName = "MicrosoftGraphNetworkaccessDeviceReportWithStartDateTimeWithEndDateTimeWithDiscoveredApplicationSegmentId";
+        var longName = string.Concat(Enumerable.Repeat("MicrosoftGraphNetworkaccessDeviceReportSegment", 8)); // 368 chars > 200
         var result = longName.ShortenNameSegment();
-        Assert.Equal(64, result.Length);
-        // First 55 chars are preserved (64 - 8 hash - 1 underscore)
-        Assert.StartsWith("MicrosoftGraphNetworkaccessDeviceReportWithStartDateTim", result);
-        Assert.Contains("_", result);
+        Assert.Equal(200, result.Length);
+        // First 191 chars are preserved (200 - 8 hash - 1 underscore)
+        Assert.StartsWith(longName[..191], result);
+        Assert.Equal('_', result[191]);
     }
     [Fact]
     public void ShortenNameSegmentIsDeterministic()
     {
-        var longName = "MicrosoftGraphNetworkaccessDeviceReportWithStartDateTimeWithEndDateTimeWithDiscoveredApplicationSegmentId";
+        var longName = string.Concat(Enumerable.Repeat("MicrosoftGraphNetworkaccessDeviceReportSegment", 8)); // 368 chars > 255
         var result1 = longName.ShortenNameSegment();
         var result2 = longName.ShortenNameSegment();
         Assert.Equal(result1, result2);
     }
     [Fact]
     public void ShortenNameSegmentProducesDifferentResultsForDifferentInputs()
     {
-        var name1 = "MicrosoftGraphNetworkaccessDeviceReportWithStartDateTimeWithEndDateTimeWithDiscoveredApplicationSegmentId";
-        var name2 = "MicrosoftGraphNetworkaccessDeviceReportWithStartDateTimeWithEndDateTimeWithApplicationId";
+        var name1 = string.Concat(Enumerable.Repeat("MicrosoftGraphNetworkaccessDeviceReportSegment", 8)) + "One"; // > 255
+        var name2 = string.Concat(Enumerable.Repeat("MicrosoftGraphNetworkaccessDeviceReportSegment", 8)) + "Two"; // > 255
         var result1 = name1.ShortenNameSegment();
         var result2 = name2.ShortenNameSegment();
         Assert.NotEqual(result1, result2);

tests/Kiota.Builder.Tests/Refiners/JavaLanguageRefinerTests.cs

@@ -774,7 +774,7 @@ public async Task AddsUsingForUntypedNodeInMethodParameterAsync()
     public async Task ShortensOversizedNamespaceSegmentsAsync()
     {
         // Simulate the problematic long namespace segment from OData functions with many parameters
-        var longSegment = "microsoftgraphnetworkaccessdevicereportwithstartdatetimewithenddatetimediscoveredapplicationsegmentiddiscoveredapplicationsegmentidapplicationidapplicationidaiagentidaiagentidaiagentnameaiagentnamecloudapplicationnamecloudapplicationname";
+        var longSegment = string.Concat(Enumerable.Repeat("microsoftgraphnetworkaccessdevicereportsegment", 6)); // 276 chars > 255
         var childNs = root.AddNamespace($"com.microsoft.graph.beta.networkaccess.reports.{longSegment}");
         var requestBuilderClass = childNs.AddClass(new CodeClass
         {
@@ -791,11 +791,11 @@ public async Task ShortensOversizedNamespaceSegmentsAsync()
         var nameSegments = childNs.Name.Split('.');
         foreach (var segment in nameSegments)
         {
-            Assert.True(segment.Length <= 64, $"Segment '{segment}' exceeds 64 chars (length: {segment.Length})");
+            Assert.True(segment.Length <= 200, $"Segment '{segment}' exceeds 200 chars (length: {segment.Length})");
         }
 
         // Class name should be shortened
-        Assert.True(requestBuilderClass.Name.Length <= 64, $"Class name '{requestBuilderClass.Name}' exceeds 64 chars (length: {requestBuilderClass.Name.Length})");
+        Assert.True(requestBuilderClass.Name.Length <= 200, $"Class name '{requestBuilderClass.Name}' exceeds 200 chars (length: {requestBuilderClass.Name.Length})");
 
         // Doc comment should contain original name for disambiguation
         Assert.Contains("Original name:", requestBuilderClass.Documentation.DescriptionTemplate);
@@ -816,7 +816,7 @@ public async Task DoesNotShortenNormalLengthNamespacesAsync()
     [Fact]
     public async Task ShorteningIsDeterministicAsync()
     {
-        var longSegment = "microsoftgraphnetworkaccessdevicereportwithstartdatetimewithenddatetimediscoveredapplicationsegmentiddiscoveredapplicationsegmentid";
+        var longSegment = string.Concat(Enumerable.Repeat("microsoftgraphnetworkaccessdevicereportsegment", 6)); // 276 chars > 255
         var root2 = CodeNamespace.InitRootNamespace();
         var childNs1 = root.AddNamespace($"com.microsoft.graph.beta.{longSegment}");
         var childNs2 = root2.AddNamespace($"com.microsoft.graph.beta.{longSegment}");
@@ -830,7 +830,7 @@ public async Task ShorteningIsDeterministicAsync()
     public async Task ShortenedClassNameIsReflectedInMethodReturnTypeAsync()
     {
         // Simulate: parent request builder has a method returning a child request builder with a long name
-        var longClassName = "MicrosoftGraphNetworkaccessDeviceReportWithStartDateTimeWithEndDateTimeRequestBuilder";
+        var longClassName = string.Concat(Enumerable.Repeat("MicrosoftGraphNetworkAccessDeviceReportSegment", 6)) + "RequestBuilder"; // > 255
         var parentNs = root.AddNamespace("com.microsoft.graph.beta.networkaccess.reports");
         var longSegment = "microsoftgraphnetworkaccessdevicereportwithstartdatetimewithenddatetime";
         var childNs = root.AddNamespace($"com.microsoft.graph.beta.networkaccess.reports.{longSegment}");
@@ -861,16 +861,16 @@ public async Task ShortenedClassNameIsReflectedInMethodReturnTypeAsync()
         await ILanguageRefiner.RefineAsync(new GenerationConfiguration { Language = GenerationLanguage.Java }, root, cancellationToken: TestContext.Current.CancellationToken);
 
         // The class should be shortened
-        Assert.True(targetClass.Name.Length <= 64, $"Class name '{targetClass.Name}' exceeds 64 chars");
+        Assert.True(targetClass.Name.Length <= 200, $"Class name '{targetClass.Name}' exceeds 200 chars");
 
         // The method's return type should automatically reflect the shortened name via TypeDefinition
         Assert.Equal(targetClass.Name, returnType.Name);
-        Assert.True(returnType.Name.Length <= 64, $"Return type name '{returnType.Name}' exceeds 64 chars");
+        Assert.True(returnType.Name.Length <= 200, $"Return type name '{returnType.Name}' exceeds 200 chars");
     }
     [Fact]
     public async Task ShorteningWorksWhenDocumentationIsNullAsync()
     {
-        var longSegment = "microsoftgraphnetworkaccessdevicereportwithstartdatetimewithenddatetimediscoveredapplicationsegmentiddiscoveredapplicationsegmentid";
+        var longSegment = string.Concat(Enumerable.Repeat("microsoftgraphnetworkaccessdevicereportsegment", 6)); // 276 chars > 255
         var childNs = root.AddNamespace($"com.microsoft.graph.beta.{longSegment}");
         var requestBuilderClass = childNs.AddClass(new CodeClass
         {
@@ -883,7 +883,7 @@ public async Task ShorteningWorksWhenDocumentationIsNullAsync()
         await ILanguageRefiner.RefineAsync(new GenerationConfiguration { Language = GenerationLanguage.Java }, root, cancellationToken: TestContext.Current.CancellationToken);
 
         // Should shorten without throwing
-        Assert.True(requestBuilderClass.Name.Length <= 64);
+        Assert.True(requestBuilderClass.Name.Length <= 200);
     }
     #endregion
 }

tests/Kiota.Builder.Tests/Refiners/PhpLanguageRefinerTests.cs

@@ -303,7 +303,7 @@ public async Task DoesNotCreateDuplicateComposedTypeWrapperIfOneAlreadyExistsAsy
     [Fact]
     public async Task ShortensOversizedNamespaceSegmentsAsync()
     {
-        var longSegment = "MicrosoftGraphNetworkaccessDeviceReportWithStartDateTimeWithEndDateTimeDiscoveredApplicationSegmentIdDiscoveredApplicationSegmentIdApplicationIdApplicationId";
+        var longSegment = string.Concat(Enumerable.Repeat("MicrosoftGraphNetworkAccessDeviceReportSegment", 6)); // 276 chars > 255
         var childNs = root.AddNamespace($"ApiSdk.NetworkAccess.Reports.{longSegment}");
         var requestBuilderClass = childNs.AddClass(new CodeClass
         {
@@ -319,18 +319,18 @@ public async Task ShortensOversizedNamespaceSegmentsAsync()
         // Namespace segment should be shortened
         foreach (var segment in childNs.Name.Split('.'))
         {
-            Assert.True(segment.Length <= 64, $"Segment '{segment}' exceeds 64 chars (length: {segment.Length})");
+            Assert.True(segment.Length <= 200, $"Segment '{segment}' exceeds 200 chars (length: {segment.Length})");
         }
 
         // Class name should be shortened
-        Assert.True(requestBuilderClass.Name.Length <= 64, $"Class name '{requestBuilderClass.Name}' exceeds 64 chars");
+        Assert.True(requestBuilderClass.Name.Length <= 200, $"Class name '{requestBuilderClass.Name}' exceeds 200 chars");
     }
     [Fact]
     public async Task ShortenedClassImportsAreConsistentAsync()
     {
         // Parent request builder references a child with a long name via method return type
         var parentNs = root.AddNamespace("ApiSdk.NetworkAccess.Reports");
-        var longSegment = "MicrosoftGraphNetworkaccessDeviceReportWithStartDateTimeWithEndDateTimeDiscoveredApplicationSegmentId";
+        var longSegment = string.Concat(Enumerable.Repeat("MicrosoftGraphNetworkAccessDeviceReportSegment", 6)); // 276 chars > 255
         var childNs = root.AddNamespace($"ApiSdk.NetworkAccess.Reports.{longSegment}");
 
         var targetClass = childNs.AddClass(new CodeClass
@@ -363,7 +363,7 @@ public async Task ShortenedClassImportsAreConsistentAsync()
             var nsSegments = u.Name.Split('.');
             foreach (var seg in nsSegments)
             {
-                Assert.True(seg.Length <= 64, $"Using namespace segment '{seg}' exceeds 64 chars — stale pre-shortened name");
+                Assert.True(seg.Length <= 200, $"Using namespace segment '{seg}' exceeds 200 chars — stale pre-shortened name");
             }
         }
     }

tests/Kiota.Builder.Tests/Refiners/PythonLanguageRefinerTests.cs

@@ -652,4 +652,85 @@ public async Task ReplacesUntypedNodeInMethodParameterAndReturnTypeAsync()
         Assert.Equal("bytes", method.ReturnType.Name);// return type is renamed to use the stream type
     }
     #endregion
+    #region NameShortening
+    [Fact]
+    public async Task ShortensOversizedNamespaceSegmentsAsync()
+    {
+        // Simulate the problematic long namespace segment from OData functions with many parameters
+        var longSegment = string.Concat(Enumerable.Repeat("microsoftgraphnetworkaccessdevicereportsegment", 6)); // 276 chars > 255
+        var childNs = root.AddNamespace($"graph.networkaccess.reports.{longSegment}");
+        var requestBuilderClass = childNs.AddClass(new CodeClass
+        {
+            Name = $"{longSegment}RequestBuilder",
+            Kind = CodeClassKind.RequestBuilder,
+            Documentation = new()
+            {
+                DescriptionTemplate = "Builds and executes requests for operations under /networkAccess/reports/...",
+            },
+        }).First();
+        await ILanguageRefiner.RefineAsync(new GenerationConfiguration { Language = GenerationLanguage.Python }, root, cancellationToken: TestContext.Current.CancellationToken);
+
+        // Namespace segment should be shortened
+        foreach (var segment in childNs.Name.Split('.'))
+        {
+            Assert.True(segment.Length <= 200, $"Segment '{segment}' exceeds 200 chars (length: {segment.Length})");
+        }
+
+        // Class name should be shortened
+        Assert.True(requestBuilderClass.Name.Length <= 200, $"Class name '{requestBuilderClass.Name}' exceeds 200 chars (length: {requestBuilderClass.Name.Length})");
+
+        // Doc comment should contain original name for disambiguation
+        Assert.Contains("Original name:", requestBuilderClass.Documentation.DescriptionTemplate);
+    }
+    [Fact]
+    public async Task DoesNotShortenNormalLengthNamespacesAsync()
+    {
+        var childNs = root.AddNamespace("graph.networkaccess.users");
+        childNs.AddClass(new CodeClass
+        {
+            Name = "UsersRequestBuilder",
+            Kind = CodeClassKind.RequestBuilder,
+        });
+        await ILanguageRefiner.RefineAsync(new GenerationConfiguration { Language = GenerationLanguage.Python }, root, cancellationToken: TestContext.Current.CancellationToken);
+
+        Assert.Equal("graph.networkaccess.users", childNs.Name);
+    }
+    [Fact]
+    public async Task DoesNotShortenSegmentsWithinThresholdAsync()
+    {
+        // 150 characters: above the previous 64/128 thresholds but within the current 200 threshold,
+        // so it must be preserved verbatim (both namespace segment and type name).
+        var mediumSegment = new string('a', 150);
+        var childNs = root.AddNamespace($"graph.networkaccess.{mediumSegment}");
+        var requestBuilderClass = childNs.AddClass(new CodeClass
+        {
+            Name = mediumSegment,
+            Kind = CodeClassKind.RequestBuilder,
+        }).First();
+        await ILanguageRefiner.RefineAsync(new GenerationConfiguration { Language = GenerationLanguage.Python }, root, cancellationToken: TestContext.Current.CancellationToken);
+
+        Assert.EndsWith($".{mediumSegment}", childNs.Name);
+        // The type name is left intact (case normalization aside) — not hash-shortened.
+        Assert.Equal(mediumSegment.Length, requestBuilderClass.Name.Length);
+        Assert.Equal(mediumSegment, requestBuilderClass.Name, ignoreCase: true);
+    }
+    [Fact]
+    public async Task ShorteningWorksWhenDocumentationIsNullAsync()
+    {
+        var longSegment = string.Concat(Enumerable.Repeat("microsoftgraphnetworkaccessdevicereportsegment", 6)); // 276 chars > 255
+        var childNs = root.AddNamespace($"graph.networkaccess.{longSegment}");
+        var requestBuilderClass = childNs.AddClass(new CodeClass
+        {
+            Name = $"{longSegment}RequestBuilder",
+            Kind = CodeClassKind.RequestBuilder,
+        }).First();
+        // Explicitly set Documentation to null to test the defensive null guard
+        requestBuilderClass.Documentation = null!;
+
+        await ILanguageRefiner.RefineAsync(new GenerationConfiguration { Language = GenerationLanguage.Python }, root, cancellationToken: TestContext.Current.CancellationToken);
+
+        // Should shorten without throwing
+        Assert.True(requestBuilderClass.Name.Length <= 200);
+    }
+    #endregion
 }

tests/Kiota.Builder.Tests/Refiners/TypeScriptLanguageRefinerTests.cs

@@ -93,7 +93,7 @@ public async Task AddStaticMethodsUsingsForDeserializerAsync()
     [Fact]
     public async Task ShortensOversizedNamespaceSegmentsAsync()
     {
-        var longSegment = "MicrosoftGraphNetworkaccessDeviceReportWithStartDateTimeWithEndDateTimeDiscoveredApplicationSegmentIdDiscoveredApplicationSegmentIdApplicationIdApplicationId";
+        var longSegment = string.Concat(Enumerable.Repeat("MicrosoftGraphNetworkAccessDeviceReportSegment", 6)); // 276 chars > 255
         var childNs = root.AddNamespace($"ApiSdk.NetworkAccess.Reports.{longSegment}");
         var requestBuilderClass = childNs.AddClass(new CodeClass
         {
@@ -120,7 +120,7 @@ public async Task ShortensOversizedNamespaceSegmentsAsync()
         // TypeScript maps namespaces (not type names) to directories, so only segments are shortened.
         foreach (var segment in childNs.Name.Split('.'))
         {
-            Assert.True(segment.Length <= 64, $"Segment '{segment}' exceeds 64 chars (length: {segment.Length})");
+            Assert.True(segment.Length <= 200, $"Segment '{segment}' exceeds 200 chars (length: {segment.Length})");
         }
 
         // Type names must be left intact: TypeScript groups types into index.ts barrels and relies on