[tcgc] add disableUsageAccessPropagationToBase flag and separate exception usage from output usage

.chronus/changes/add_usage_helper-2024-10-11-17-1-36.md

@@ -0,0 +1,7 @@
+---
+changeKind: feature
+packages:
+  - "@azure-tools/typespec-client-generator-core"
+---
+
+add `disableUsageAccessPropagationToBase` to support language that does not generate base model

packages/typespec-client-generator-core/src/decorators.ts

@@ -615,6 +615,7 @@ export function createTCGCContext(program: Program, emitterName: string): TCGCCo
     __tspTypeToApiVersions: new Map(),
     __clientToApiVersionClientDefaultValue: new Map(),
     previewStringRegex: /-preview$/,
+    disableUsageAccessPropagationToBase: false,
   };
 }
 
@@ -626,6 +627,7 @@ interface VersioningStrategy {
 export interface CreateSdkContextOptions {
   readonly versioning?: VersioningStrategy;
   additionalDecorators?: string[];
+  disableUsageAccessPropagationToBase?: boolean; // this flag is for some languages that has no need to generate base model, but generate model with composition
 }
 
 export async function createSdkContext<
@@ -658,6 +660,7 @@ export async function createSdkContext<
     examplesDir: context.options["examples-dir"] ?? context.options["examples-directory"],
     decoratorsAllowList: [...defaultDecoratorsAllowList, ...(options?.additionalDecorators ?? [])],
     previewStringRegex: options?.versioning?.previewStringRegex || tcgcContext.previewStringRegex,
+    disableUsageAccessPropagationToBase: options?.disableUsageAccessPropagationToBase ?? false,
   };
   sdkContext.sdkPackage = diagnostics.pipe(getSdkPackage(sdkContext));
   for (const client of sdkContext.sdkPackage.clients) {

packages/typespec-client-generator-core/src/interfaces.ts

@@ -53,6 +53,7 @@ export interface TCGCContext {
   examplesDir?: string;
   decoratorsAllowList?: string[];
   previewStringRegex: RegExp;
+  disableUsageAccessPropagationToBase: boolean;
 }
 
 export interface SdkContext<

packages/typespec-client-generator-core/src/types.ts

@@ -1446,7 +1446,6 @@ function updateUsageOrAccess(
   }
 
   if (type.kind === "enum") return diagnostics.wrap(undefined);
-  if (!options.propagation) return diagnostics.wrap(undefined);
   if (type.kind === "union") {
     for (const unionType of type.variantTypes) {
       diagnostics.pipe(updateUsageOrAccess(context, value, unionType, options));
@@ -1457,7 +1456,9 @@ function updateUsageOrAccess(
     diagnostics.pipe(updateUsageOrAccess(context, value, type.type, options));
     return diagnostics.wrap(undefined);
   }
-  if (type.baseModel) {
+
+  if (!options.propagation) return diagnostics.wrap(undefined);
+  if (type.baseModel && !context.disableUsageAccessPropagationToBase) {
     options.ignoreSubTypeStack.push(true);
     diagnostics.pipe(updateUsageOrAccess(context, value, type.baseModel, options));
     options.ignoreSubTypeStack.pop();

packages/typespec-client-generator-core/test/decorators/access.test.ts

@@ -730,4 +730,62 @@ describe("typespec-client-generator-core: @access", () => {
       code: "@azure-tools/typespec-client-generator-core/conflict-access-override",
     });
   });
+
+  it("disableUsageAccessPropagationToBase true with override", async () => {
+    runner = await createSdkTestRunner(
+      { emitterName: "@azure-tools/typespec-python" },
+      { disableUsageAccessPropagationToBase: true },
+    );
+    await runner.compileWithBuiltInService(
+      `
+        model BaseClassThatsPruned {
+          id: int32;
+        }
+        model DerivedOne extends BaseClassThatsPruned {
+          name: string;
+          prop: UsedByProperty;
+        }
+        model UsedByProperty {
+          prop: string;
+        }
+        @@usage(DerivedOne, Usage.output);
+        @@access(DerivedOne, Access.public);
+      `,
+    );
+    const models = runner.context.sdkPackage.models;
+    strictEqual(models.length, 2);
+    strictEqual(models[0].access, "public");
+    strictEqual(models[0].name, "DerivedOne");
+    strictEqual(models[1].access, "public");
+    strictEqual(models[1].name, "UsedByProperty");
+  });
+
+  it("disableUsageAccessPropagationToBase true", async () => {
+    runner = await createSdkTestRunner(
+      { emitterName: "@azure-tools/typespec-python" },
+      { disableUsageAccessPropagationToBase: true },
+    );
+    await runner.compileWithBuiltInService(
+      `
+        model BaseClassThatsPruned {
+          id: int32;
+        }
+        model DerivedOne extends BaseClassThatsPruned {
+          name: string;
+          prop: UsedByProperty;
+        }
+        model UsedByProperty {
+          prop: string;
+        }
+
+        op test(): DerivedOne;
+      `,
+    );
+    const models = runner.context.sdkPackage.models;
+    strictEqual(models.length, 2);
+    strictEqual(models[0].access, "public");
+    strictEqual(models[0].name, "DerivedOne");
+    strictEqual(models[1].access, "public");
+    strictEqual(models[1].name, "UsedByProperty");
+  });
 });

packages/typespec-client-generator-core/test/decorators/usage.test.ts

@@ -459,4 +459,61 @@ describe("typespec-client-generator-core: @usage", () => {
     strictEqual(models[1].usage, UsageFlags.Output);
     strictEqual(models[1].access, "public");
   });
+
+  it("disableUsageAccessPropagationToBase true with override", async () => {
+    runner = await createSdkTestRunner(
+      { emitterName: "@azure-tools/typespec-python" },
+      { disableUsageAccessPropagationToBase: true },
+    );
+    await runner.compileWithBuiltInService(
+      `
+        model BaseClassThatsPruned {
+          id: int32;
+        }
+        model DerivedOne extends BaseClassThatsPruned {
+          name: string;
+          prop: UsedByProperty;
+        }
+        model UsedByProperty {
+          prop: string;
+        }
+        @@usage(DerivedOne, Usage.output);
+      `,
+    );
+    const models = runner.context.sdkPackage.models;
+    strictEqual(models.length, 2);
+    strictEqual(models[0].usage, UsageFlags.Output);
+    strictEqual(models[0].name, "DerivedOne");
+    strictEqual(models[1].usage, UsageFlags.Output);
+    strictEqual(models[1].name, "UsedByProperty");
+  });
+
+  it("disableUsageAccessPropagationToBase true", async () => {
+    runner = await createSdkTestRunner(
+      { emitterName: "@azure-tools/typespec-python" },
+      { disableUsageAccessPropagationToBase: true },
+    );
+    await runner.compileWithBuiltInService(
+      `
+        model BaseClassThatsPruned {
+          id: int32;
+        }
+        model DerivedOne extends BaseClassThatsPruned {
+          name: string;
+          prop: UsedByProperty;
+        }
+        model UsedByProperty {
+          prop: string;
+        }
+
+        op test(): DerivedOne;
+      `,
+    );
+    const models = runner.context.sdkPackage.models;
+    strictEqual(models.length, 2);
+    strictEqual(models[0].usage, UsageFlags.Output | UsageFlags.Json);
+    strictEqual(models[0].name, "DerivedOne");
+    strictEqual(models[1].usage, UsageFlags.Output | UsageFlags.Json);
+    strictEqual(models[1].name, "UsedByProperty");
+  });
 });