[pull] main from fern-api:main

generators/csharp/base/src/asIs/test/Utils/JsonElementComparer.Template.cs

@@ -92,8 +92,14 @@ private bool CompareJsonElements(JsonElement x, JsonElement y, string path)
             case JsonValueKind.Number:
                 if (x.GetDecimal() != y.GetDecimal())
                 {
-                    _failurePath = $"{path}: Expected {x.GetDecimal()} but got {y.GetDecimal()}";
-                    return false;
+                    if (x.GetDouble() != y.GetDouble())
+                    {
+                        if (x.GetSingle() != y.GetSingle())
+                        {
+                            _failurePath = $"{path}: Expected {x.GetDecimal()} but got {y.GetDecimal()}";
+                            return false;
+                        }
+                    }
                 }
 
                 return true;

generators/csharp/base/src/context/GeneratorContext.ts

@@ -668,6 +668,10 @@ export abstract class GeneratorContext extends AbstractGeneratorContext {
         return undefined;
     }
 
+    public isLiteralValue(typeReference: TypeReference): boolean {
+        return this.getLiteralValue(typeReference) != null;
+    }
+
     public getLiteralValue(typeReference: TypeReference): string | boolean | undefined {
         if (typeReference.type === "container" && typeReference.container.type === "literal") {
             const literal = typeReference.container.literal;

generators/csharp/dynamic-snippets/src/EndpointSnippetGenerator.ts

@@ -79,11 +79,13 @@ export class EndpointSnippetGenerator extends WithGeneration {
         snippet: FernIr.dynamic.EndpointSnippetRequest;
         options: Options;
     }): ast.AstNode {
-        // if we're actually passed the examples, we need to
-        // check that the endpoint that we're generating has an example that matches the snippet
+        // If we're passed endpoint examples and the snippet includes an id (i.e. it's an
+        // EndpointExample, not just an EndpointSnippetRequest), verify the id matches one of
+        // the examples. Snippets without an id are user-provided requests and skip this check.
         if (
             endpoint.examples &&
-            !endpoint.examples?.find((each) => is.DynamicIR.EndpointExample(snippet) && each.id === snippet.id)
+            is.DynamicIR.EndpointExample(snippet) &&
+            !endpoint.examples.find((each) => each.id === snippet.id)
         ) {
             // the dsg expects us to just throw when there is nothing to generate.
             throw new Error("Endpoint does not have an example that matches the snippet");

generators/csharp/dynamic-snippets/src/__test__/DynamicSnippetsGenerator.test.ts

@@ -1,6 +1,9 @@
-import { DynamicSnippetsTestRunner } from "@fern-api/browser-compatible-base-generator";
+import { DynamicSnippetsTestRunner, Style } from "@fern-api/browser-compatible-base-generator";
+import { FernIr } from "@fern-api/dynamic-ir-sdk";
 import { AbsoluteFilePath, join } from "@fern-api/path-utils";
+import { readFileSync } from "fs";
 
+import { DynamicSnippetsGenerator } from "../DynamicSnippetsGenerator.js";
 import { buildDynamicSnippetsGenerator } from "./utils/buildDynamicSnippetsGenerator.js";
 import { buildGeneratorConfig } from "./utils/buildGeneratorConfig.js";
 
@@ -16,6 +19,71 @@ const DYNAMIC_IR_TEST_DEFINITIONS_DIRECTORY = AbsoluteFilePath.of(
     `${__dirname}/../../../../../packages/cli/generation/ir-generator-tests/src/dynamic-snippets/__test__/test-definitions`
 );
 
+describe("snippets (endpoint with examples)", () => {
+    test("generates snippet for EndpointSnippetRequest when endpoint has examples", async () => {
+        const irFilepath = AbsoluteFilePath.of(join(DYNAMIC_IR_TEST_DEFINITIONS_DIRECTORY, "imdb.json"));
+        const ir: FernIr.dynamic.DynamicIntermediateRepresentation = JSON.parse(readFileSync(irFilepath, "utf-8"));
+
+        // Inject examples onto the POST /movies/create-movie endpoint so the guard is exercised.
+        for (const endpoint of Object.values(ir.endpoints)) {
+            if (endpoint.location.path === "/movies/create-movie" && endpoint.location.method === "POST") {
+                endpoint.examples = [
+                    {
+                        id: "example-1",
+                        name: undefined,
+                        endpoint: endpoint.location,
+                        baseURL: undefined,
+                        environment: undefined,
+                        auth: {
+                            type: "bearer",
+                            token: "<token>"
+                        },
+                        pathParameters: undefined,
+                        queryParameters: undefined,
+                        headers: undefined,
+                        requestBody: {
+                            title: "Example Movie",
+                            rating: 7.5
+                        }
+                    }
+                ];
+            }
+        }
+
+        const generator = new DynamicSnippetsGenerator({
+            ir,
+            config: buildGeneratorConfig(),
+            options: { style: Style.Concise }
+        });
+
+        // Call generate with a plain EndpointSnippetRequest (no id).
+        // Before the fix, this threw "Endpoint does not have an example that matches the snippet".
+        const response = await generator.generate({
+            endpoint: {
+                method: "POST",
+                path: "/movies/create-movie"
+            },
+            baseURL: undefined,
+            environment: undefined,
+            auth: {
+                type: "bearer",
+                token: "<YOUR_API_KEY>"
+            },
+            pathParameters: undefined,
+            queryParameters: undefined,
+            headers: undefined,
+            requestBody: {
+                title: "The Matrix",
+                rating: 8.2
+            }
+        });
+
+        expect(response.errors).toBeUndefined();
+        expect(response.snippet).toBeTruthy();
+        expect(response.snippet).toMatchSnapshot();
+    });
+});
+
 describe("snippets (use-undiscriminated-unions)", () => {
     const generator = buildDynamicSnippetsGenerator({
         irFilepath: AbsoluteFilePath.of(join(DYNAMIC_IR_TEST_DEFINITIONS_DIRECTORY, "exhaustive.json")),

generators/csharp/dynamic-snippets/src/__test__/__snapshots__/DynamicSnippetsGenerator.test.ts.snap

@@ -276,32 +276,29 @@ await client.Endpoints.Container.GetAndReturnListOfPrimitivesAsync(
 `;
 
 exports[`snippets (default) > exhaustive > 'POST /container/map-prim-to-union (mi…' 1`] = `
-"[
-  {
-    "severity": "CRITICAL",
-    "path": [
-      "requestBody",
-      "test2"
-    ],
-    "message": "Expected number, got boolean"
-  },
-  {
-    "severity": "CRITICAL",
-    "path": [
-      "requestBody",
-      "test3"
-    ],
-    "message": "Expected number, got string"
-  },
-  {
-    "severity": "CRITICAL",
-    "path": [
-      "requestBody",
-      "test4"
-    ],
-    "message": "Expected number, got object"
-  }
-]"
+"using Acme;
+using System.Collections.Generic;
+using OneOf;
+
+var client = new AcmeClient(
+    token: "<YOUR_API_KEY>"
+);
+
+await client.Endpoints.Container.GetAndReturnMapOfPrimToUndiscriminatedUnionAsync(
+    new Dictionary<string, OneOf<double, bool, string, IEnumerable<string>>>(){
+        ["test"] = 0,
+        ["test2"] = true,
+        ["test3"] = "Test",
+        ["test4"] = new List<string>(){
+            "1",
+            "1",
+            "1",
+            "1",
+        }
+        ,
+    }
+);
+"
 `;
 
 exports[`snippets (default) > file-upload > 'POST /' 1`] = `
@@ -706,6 +703,23 @@ exports[`snippets (default) > single-url-environment-default > 'invalid environm
 ]"
 `;
 
+exports[`snippets (endpoint with examples) > generates snippet for EndpointSnippetRequest when endpoint has examples 1`] = `
+"using Acme;
+using Acme.Imdb;
+
+var client = new AcmeClient(
+    token: "<YOUR_API_KEY>"
+);
+
+await client.Imdb.CreateMovieAsync(
+    new CreateMovieRequest {
+        Title = "The Matrix",
+        Rating = 8.2
+    }
+);
+"
+`;
+
 exports[`snippets (use-undiscriminated-unions) > POST /container/map-prim-to-union (mixed values) 1`] = `
 "using Acme;
 using System.Collections.Generic;
@@ -718,6 +732,15 @@ var client = new AcmeClient(
 await client.Endpoints.Container.GetAndReturnMapOfPrimToUndiscriminatedUnionAsync(
     new Dictionary<string, MixedType>(){
         ["test"] = 0,
+        ["test2"] = true,
+        ["test3"] = "Test",
+        ["test4"] = new List<string>(){
+            "1",
+            "1",
+            "1",
+            "1",
+        }
+        ,
     }
 );
 "

generators/csharp/dynamic-snippets/src/context/DynamicLiteralMapper.ts

@@ -657,10 +657,16 @@ export class DynamicLiteralMapper extends WithGeneration {
         value: unknown;
     }): { valueTypeReference: FernIr.dynamic.TypeReference; typeLiteral: ast.Literal } | undefined {
         for (const typeReference of undiscriminatedUnion.types) {
+            const errorsBefore = this.context.errors.size();
             try {
                 const typeLiteral = this.convert({ typeReference, value });
+                if (is.Literal.nop(typeLiteral) || this.context.errors.size() > errorsBefore) {
+                    this.context.errors.truncate(errorsBefore);
+                    continue;
+                }
                 return { valueTypeReference: typeReference, typeLiteral };
             } catch (e) {
+                this.context.errors.truncate(errorsBefore);
                 continue;
             }
         }

generators/csharp/model/src/object/ObjectGenerator.ts

@@ -173,19 +173,37 @@ export class ObjectGenerator extends FileGenerator<CSharpFile, ModelGeneratorCon
         exampleObject: ExampleObjectType;
         parseDatetimes: boolean;
     }): ast.CodeBlock {
-        const args = exampleObject.properties.map((exampleProperty) => {
-            const propertyName = this.getPropertyName({
-                className: this.classReference.name,
-                objectProperty: exampleProperty.name
-            });
-            const assignment = this.exampleGenerator.getSnippetForTypeReference({
-                exampleTypeReference: exampleProperty.value,
-                parseDatetimes
+        // When generateLiterals is enabled, collect wire values of literal properties so we
+        // can skip them in the object initializer. Their default `= new()` already sets the
+        // correct value and assigning a plain string would cause a CS0029 compilation error.
+        const literalPropertyWireValues = new Set<string>();
+        if (this.generation.settings.generateLiterals) {
+            const allProps = [
+                ...this.objectDeclaration.properties,
+                ...(this.objectDeclaration.extendedProperties ?? [])
+            ];
+            for (const prop of allProps) {
+                if (this.context.isLiteralValue(prop.valueType)) {
+                    literalPropertyWireValues.add(getWireValue(prop.name));
+                }
+            }
+        }
+
+        const args = exampleObject.properties
+            .filter((exampleProperty) => !literalPropertyWireValues.has(getWireValue(exampleProperty.name)))
+            .map((exampleProperty) => {
+                const propertyName = this.getPropertyName({
+                    className: this.classReference.name,
+                    objectProperty: exampleProperty.name
+                });
+                const assignment = this.exampleGenerator.getSnippetForTypeReference({
+                    exampleTypeReference: exampleProperty.value,
+                    parseDatetimes
+                });
+                // todo: considering filtering out "assignments" are are actually just null so that null properties
+                // are completely excluded from object initializers
+                return { name: propertyName, assignment };
             });
-            // todo: considering filtering out "assignments" are are actually just null so that null properties
-            // are completely excluded from object initializers
-            return { name: propertyName, assignment };
-        });
 
         // Include default values for required properties missing from the example
         // so the generated object initializer compiles without CS9035 errors.
@@ -198,6 +216,10 @@ export class ObjectGenerator extends FileGenerator<CSharpFile, ModelGeneratorCon
             if (providedWireValues.has(getWireValue(property.name))) {
                 continue;
             }
+            // Skip literal properties when generateLiterals is enabled; they have correct defaults.
+            if (literalPropertyWireValues.has(getWireValue(property.name))) {
+                continue;
+            }
             if (this.isRequiredProperty(property.valueType)) {
                 const propertyName = this.getPropertyName({
                     className: this.classReference.name,

generators/csharp/model/versions.yml

@@ -1,4 +1,16 @@
 # yaml-language-server: $schema=../../../fern-versions-yml.schema.json
+- version: 0.9.1-rc.0
+  changelogEntry:
+    - summary: |
+        Fix snippet generation to skip literal properties in object initializers
+        when `generate-literals` is enabled. Previously, the generator emitted
+        plain string/boolean assignments for `TypeLiteral` properties, causing
+        CS0029 compilation errors. Literal properties now rely on their `= new()`
+        default initializer.
+      type: fix
+  createdAt: "2026-04-09"
+  irVersion: 66
+
 - version: 0.9.0-rc.0
   changelogEntry:
     - summary: |

generators/csharp/sdk/src/wrapped-request/WrappedRequestGenerator.ts

@@ -345,6 +345,22 @@ export class WrappedRequestGenerator extends FileGenerator<CSharpFile, SdkGenera
             });
         }
 
+        // When generateLiterals is enabled, collect wire values of literal properties from
+        // the endpoint's inlined request body so we can skip them in the object initializer.
+        // Their default `= new()` already sets the correct value and assigning a plain string
+        // would cause a CS0029 compilation error.
+        const literalBodyPropertyWireValues = new Set<string>();
+        if (this.generation.settings.generateLiterals && this.endpoint.requestBody?.type === "inlinedRequestBody") {
+            for (const prop of [
+                ...this.endpoint.requestBody.properties,
+                ...(this.endpoint.requestBody.extendedProperties ?? [])
+            ]) {
+                if (this.context.isLiteralValue(prop.valueType)) {
+                    literalBodyPropertyWireValues.add(getWireValue(prop.name));
+                }
+            }
+        }
+
         example.request?._visit({
             reference: (reference) => {
                 orderedFields.push({
@@ -357,6 +373,9 @@ export class WrappedRequestGenerator extends FileGenerator<CSharpFile, SdkGenera
             },
             inlinedRequestBody: (inlinedRequestBody) => {
                 for (const property of inlinedRequestBody.properties) {
+                    if (literalBodyPropertyWireValues.has(getWireValue(property.name))) {
+                        continue;
+                    }
                     orderedFields.push({
                         name: property.name,
                         value: this.exampleGenerator.getSnippetForTypeReference({