Support serialization of object examples on unions

microsoft · Nov 23, 2024 · 4cc2335 · 4cc2335
1 parent 1226640
commit 4cc2335
Show file tree

Hide file tree

Showing 2 changed files with 28 additions and 2 deletions.
diff --git a/packages/compiler/src/lib/examples.ts b/packages/compiler/src/lib/examples.ts
@@ -25,6 +25,7 @@ export function serializeValueAsJson(
   if (type.kind === "ModelProperty") {
     return serializeValueAsJson(program, value, type.type, encodeAs ?? getEncode(program, type));
   }
+  console.log({ valueKind: value.valueKind, value, type });
   switch (value.valueKind) {
     case "NullValue":
       return null;
@@ -72,11 +73,12 @@ function resolveUnions(program: Program, value: ObjectValue, type: Type): Type |
   if (type.kind !== "Union") {
     return type;
   }
+  const exactValueType = program.checker.getValueExactType(value);
   for (const variant of type.variants.values()) {
     if (
       ignoreDiagnostics(
         program.checker.isTypeAssignableTo(
-          value.type.projectionBase ?? value.type,
+          exactValueType ?? value.type.projectionBase ?? value.type,
           variant.type.projectionBase ?? variant.type,
           value,
         ),

diff --git a/packages/compiler/test/decorators/examples.test.ts b/packages/compiler/test/decorators/examples.test.ts
@@ -173,7 +173,7 @@ describe("@example", () => {
   });
 
   describe("union", () => {
-    it("valid", async () => {
+    it("valid for union member reference", async () => {
       const { program, examples, target } = await getExamplesFor(`
       @example(test.a)
       @test union test {a: "a", b: "b"}
@@ -182,6 +182,30 @@ describe("@example", () => {
       expect(serializeValueAsJson(program, examples[0].value, target)).toEqual("a");
     });
 
+    it("valid for object value", async () => {
+      const { program, examples, target } = await getExamplesFor(`
+        model A {
+          type: "a";
+          a: string;
+        }
+        model B {
+          type: "b";
+          b: numeric;
+        }
+
+        @example(#{
+          type: "a",
+          a: "a string",
+        })
+        @test union test {a: A, b: B}
+      `);
+      expect(examples).toHaveLength(1);
+      expect(serializeValueAsJson(program, examples[0].value, target)).toEqual({
+        type: "a",
+        a: "a string",
+      });
+    });
+
     it("emit diagnostic for unassignable value", async () => {
       const diagnostics = await diagnoseCode(`
         @example(1)