Fix bug in code that processes API properties

Author: zelliott

apps/api-extractor/src/generators/ApiModelGenerator.ts

@@ -824,13 +824,20 @@ export class ApiModelGenerator {
       const nodesToCapture: IExcerptBuilderNodeToCapture[] = [];
 
       const propertyTypeTokenRange: IExcerptTokenRange = ExcerptBuilder.createEmptyTokenRange();
+      let propertyTypeNode: ts.TypeNode | undefined;
+
+      if (
+        ts.isPropertyDeclaration(astDeclaration.declaration) ||
+        ts.isGetAccessorDeclaration(astDeclaration.declaration)
+      ) {
+        propertyTypeNode = astDeclaration.declaration.type;
+      }
+
+      if (ts.isSetAccessorDeclaration(astDeclaration.declaration)) {
+        // Note that TypeScript always reports an error if a setter does not have exactly one parameter.
+        propertyTypeNode = astDeclaration.declaration.parameters[0].type;
+      }
 
-      // If the property declaration's type is `undefined`, then we're processing a setter with no corresponding
-      // getter. Use the parameter type instead (note that TypeScript always reports an error if a setter
-      // does not have exactly one parameter).
-      const propertyTypeNode: ts.TypeNode | undefined =
-        (astDeclaration.declaration as ts.PropertyDeclaration | ts.GetAccessorDeclaration).type ||
-        (astDeclaration.declaration as ts.SetAccessorDeclaration).parameters[0].type;
       nodesToCapture.push({ node: propertyTypeNode, tokenRange: propertyTypeTokenRange });
 
       const excerptTokens: IExcerptToken[] = this._buildExcerptTokens(astDeclaration, nodesToCapture);

build-tests/api-extractor-scenarios/etc/test-outputs/apiItemKinds/api-extractor-scenarios.api.json

@@ -685,6 +685,52 @@
               },
               "isStatic": false
             },
+            {
+              "kind": "Property",
+              "canonicalReference": "api-extractor-scenarios!SimpleClass#someReadonlyProp:member",
+              "docComment": "",
+              "excerptTokens": [
+                {
+                  "kind": "Content",
+                  "text": "readonly someReadonlyProp = 5;"
+                }
+              ],
+              "isOptional": false,
+              "releaseTag": "Public",
+              "name": "someReadonlyProp",
+              "propertyTypeTokenRange": {
+                "startIndex": 0,
+                "endIndex": 0
+              },
+              "isStatic": false
+            },
+            {
+              "kind": "Property",
+              "canonicalReference": "api-extractor-scenarios!SimpleClass#someReadonlyPropWithType:member",
+              "docComment": "",
+              "excerptTokens": [
+                {
+                  "kind": "Content",
+                  "text": "readonly someReadonlyPropWithType: "
+                },
+                {
+                  "kind": "Content",
+                  "text": "number"
+                },
+                {
+                  "kind": "Content",
+                  "text": ";"
+                }
+              ],
+              "isOptional": false,
+              "releaseTag": "Public",
+              "name": "someReadonlyPropWithType",
+              "propertyTypeTokenRange": {
+                "startIndex": 1,
+                "endIndex": 2
+              },
+              "isStatic": false
+            },
             {
               "kind": "Property",
               "canonicalReference": "api-extractor-scenarios!SimpleClass#writeableProperty:member",

build-tests/api-extractor-scenarios/etc/test-outputs/apiItemKinds/api-extractor-scenarios.api.md

@@ -62,6 +62,10 @@ export class SimpleClass {
     // (undocumented)
     get readonlyProperty(): string;
     // (undocumented)
+    readonly someReadonlyProp = 5;
+    // (undocumented)
+    readonly someReadonlyPropWithType: number;
+    // (undocumented)
     get writeableProperty(): string;
     set writeableProperty(value: string);
 }

build-tests/api-extractor-scenarios/etc/test-outputs/apiItemKinds/rollup.d.ts

@@ -58,6 +58,8 @@ export declare class SimpleClass {
     get readonlyProperty(): string;
     get writeableProperty(): string;
     set writeableProperty(value: string);
+    readonly someReadonlyProp = 5;
+    readonly someReadonlyPropWithType: number;
 }
 
 /** @public */

build-tests/api-extractor-scenarios/src/apiItemKinds/classes.ts

@@ -20,4 +20,7 @@ export class SimpleClass {
     return 'hello';
   }
   public set writeableProperty(value: string) {}
+
+  readonly someReadonlyProp = 5;
+  readonly someReadonlyPropWithType: number = 5;
 }