[TSP APIView] Support constant statements

tools/apiview/emitters/typespec-apiview/CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Version 0.4.9 (07-09-2024)
 Fix issue where "unknown" was rendered as "any".
 Support value syntax for objects and arrays.
+Support const statements in namespaces.
 
 ## Version 0.4.8 (04-18-2024)
 Display suppressions in APIView.

tools/apiview/emitters/typespec-apiview/src/apiview.ts

@@ -5,6 +5,7 @@ import {
   AugmentDecoratorStatementNode,
   BaseNode,
   BooleanLiteralNode,
+  ConstStatementNode,
   DecoratorExpressionNode,
   DirectiveExpressionNode,
   EnumMemberNode,
@@ -446,6 +447,15 @@ export class ApiView {
         throw new Error(`Case "BlockComment" not implemented`);
       case SyntaxKind.TypeSpecScript:
         throw new Error(`Case "TypeSpecScript" not implemented`);
+      case SyntaxKind.ConstStatement:
+        obj = node as ConstStatementNode;
+        this.namespaceStack.push(obj.id.sv);
+        this.keyword("const", false, true);
+        this.tokenizeIdentifier(obj.id, "declaration");
+        this.punctuation("=", true, true);
+        this.tokenize(obj.value);
+        this.namespaceStack.pop();
+        break;
       case SyntaxKind.DecoratorExpression:
         obj = node as DecoratorExpressionNode;
         this.punctuation("@", false, false);
@@ -1053,6 +1063,11 @@ export class ApiView {
       this.punctuation(";");
       this.blankLines(1);
     }
+    for (const node of model.constants.values()) {
+        this.tokenize(node);
+        this.punctuation(";");
+        this.blankLines(1);
+    }
     this.endGroup();
     this.blankLines(1);
     this.namespaceStack.pop();

tools/apiview/emitters/typespec-apiview/src/namespace-model.ts

@@ -32,6 +32,7 @@ import {
   DirectiveExpressionNode,
   StringLiteralNode,
   ObjectLiteralNode,
+  ConstStatementNode,
 } from "@typespec/compiler";
 
 export class NamespaceModel {
@@ -66,6 +67,7 @@ export class NamespaceModel {
   >();
   aliases = new Map<string, AliasStatementNode>();
   augmentDecorators = new Array<AugmentDecoratorStatementNode>();
+  constants = new Array<ConstStatementNode>();
 
   constructor(name: string, ns: Namespace, program: Program) {
     this.name = name;
@@ -118,6 +120,11 @@ export class NamespaceModel {
       this.augmentDecorators.push(augment);
     }
 
+    // collect contants
+    for (const constant of findNodes(SyntaxKind.ConstStatement, program, ns)) {
+      this.constants.push(constant);
+    }
+
     // sort operations and models
     this.operations = new Map([...this.operations].sort(caseInsensitiveSort));
     this.resources = new Map([...this.resources].sort(caseInsensitiveSort));

tools/apiview/emitters/typespec-apiview/test/apiview.test.ts

@@ -932,4 +932,29 @@ describe("apiview: tests", () => {
       validateDefinitionIds(apiview);
     });
   });
+
+  describe("constants", () => {
+    it("renders constants", async () => {
+      const input = `
+      #suppress "deprecated"
+      @TypeSpec.service( { title: "Test", version: "1" } )
+      namespace Azure.Test {
+        const a = 123;
+        const b = #{name: "abc"};
+        const c = a;
+      }
+      `;
+      const expect = `
+        namespace Azure.Test {
+          const a = 123;
+          const b = #{name: "abc"};
+          const c = a;
+        }
+        `;
+      const apiview = await apiViewFor(input, {});
+      const actual = apiViewText(apiview);
+      compare(expect, actual, 10);
+      validateDefinitionIds(apiview);    
+    });
+  });
 });