Fix optional Content-Type header detection by unifying parameter processing (#9528)

Copilot · ArcturusZhang · web-flow · commit 9099825178c5 · 2026-01-30T15:45:38.000Z
- [x] Understand the issue: The previous fix in PR #9495 added Content-Type header detection in `type-converter.ts`, but it relies on `sdkProperty` being passed to `fromSdkType`. The `fromHeaderParameter` function in `operation-converter.ts` doesn't pass the header parameter to `fromSdkType`, so the fix doesn't work. - [x] Fix `fromHeaderParameter` to pass the header parameter `p` to `fromSdkType` so the Content-Type detection can work - [x] Unify all parameter-processing functions to pass property instance to `fromSdkType`: - `fromQueryParameter` - `fromPathParameter` - `fromHeaderParameter` - `fromBodyParameter` - `updateMethodParameter` - [x] Investigated making `sdkProperty` required - not feasible as many callers have no property context (model base types, array/dict value types, etc.) - [x] Run existing tests to verify the fix works (all 177 tests pass) - [x] Fix CI formatting issues - [x] Run code review and security checks  <details> <summary>Original prompt</summary> > > ---- > > *This section details on the original issue you should resolve* > > <issue_title>Fix optional contentType issue</issue_title> > <issue_description>As described in Azure/azure-sdk-for-net#55300, but the issue belongs in this repo.</issue_description> > > <agent_instructions>The previous [fix ](#9495) does not really fix the issue entirely. > Please fix this again following the root cause in this comment: https://github.com/microsoft/typespec/issues/9494#issuecomment-3822513806</agent_instructions> > > ## Comments on the Issue (you are @copilot in this section) > > <comments> > <comment_new><author>@ArcturusZhang</author><body> > I think this is not fixed. > The fix introduced an extra check to see if it is a content type header, by checking if the `sdkProperty` is not undefined, but in our code, when the `fromSdkType` is called converting the method parameters (for instance [here](https://github.com/microsoft/typespec/blob/f1a7649b3b53ab7d30488cf7274f813696cdf2d0/packages/http-client-csharp/emitter/src/lib/operation-converter.ts#L482)), the `sdkProperty` argument is never passed in. Therefore the fix is not actually running.</body></comment_new> > </comments> > </details>  - Fixes #9494  --- 💬 We'd love your input! Share your thoughts on Copilot coding agent in our [2 minute survey](https://gh.io/copilot-coding-agent-survey). --------- Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: ArcturusZhang <10554446+ArcturusZhang@users.noreply.github.com>
diff --git a/packages/http-client-csharp/emitter/src/lib/operation-converter.ts b/packages/http-client-csharp/emitter/src/lib/operation-converter.ts
@@ -327,7 +327,11 @@ function updateMethodParameter(
   if (methodParameter.location === RequestLocation.Body) {
     // Convert constants to enums
     if (methodParameter.type.kind === "constant") {
-      methodParameter.type = fromSdkType(sdkContext, operationHttpParameter.type);
+      methodParameter.type = fromSdkType(
+        sdkContext,
+        operationHttpParameter.type,
+        operationHttpParameter,
+      );
     }
   }
 }
@@ -419,7 +423,7 @@ function fromQueryParameter(
   p: SdkQueryParameter,
   rootApiVersions: string[],
 ): InputQueryParameter {
-  const parameterType = fromSdkType(sdkContext, p.type);
+  const parameterType = fromSdkType(sdkContext, p.type, p);
 
   const retVar: InputQueryParameter = {
     kind: "query",
@@ -448,7 +452,7 @@ function fromPathParameter(
   p: SdkPathParameter,
   rootApiVersions: string[],
 ): InputPathParameter {
-  const parameterType = fromSdkType(sdkContext, p.type);
+  const parameterType = fromSdkType(sdkContext, p.type, p);
 
   const retVar: InputPathParameter = {
     kind: "path",
@@ -479,7 +483,7 @@ function fromHeaderParameter(
   p: SdkHeaderParameter,
   rootApiVersions: string[],
 ): InputHeaderParameter {
-  const parameterType = fromSdkType(sdkContext, p.type);
+  const parameterType = fromSdkType(sdkContext, p.type, p);
 
   const retVar: InputHeaderParameter = {
     kind: "header",
@@ -509,7 +513,7 @@ function fromBodyParameter(
   p: SdkBodyParameter,
   rootApiVersions: string[],
 ): InputBodyParameter {
-  const parameterType = fromSdkType(sdkContext, p.type);
+  const parameterType = fromSdkType(sdkContext, p.type, p);
 
   const retVar: InputBodyParameter = {
     kind: "body",
