Merge pull request #4513 from bartvandenende-wm/bartvandenende-wm/api…

…-extractor-arrow-func

[api-extractor] Classify arrow functions as function kind in the doc model exports.

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

@@ -250,14 +250,28 @@ export class ApiModelGenerator {
         break;
 
       case ts.SyntaxKind.VariableDeclaration:
-        this._processApiVariable(astDeclaration, context);
+        // check for arrow functions in variable declaration
+        const functionDeclaration: ts.FunctionDeclaration | undefined =
+          this._tryFindFunctionDeclaration(astDeclaration);
+        if (functionDeclaration) {
+          this._processApiFunction(astDeclaration, context, functionDeclaration);
+        } else {
+          this._processApiVariable(astDeclaration, context);
+        }
         break;
 
       default:
       // ignore unknown types
     }
   }
 
+  private _tryFindFunctionDeclaration(astDeclaration: AstDeclaration): ts.FunctionDeclaration | undefined {
+    const children: ts.Node[] = astDeclaration.declaration.getChildren(
+      astDeclaration.declaration.getSourceFile()
+    );
+    return children.find(ts.isFunctionTypeNode) as ts.FunctionDeclaration | undefined;
+  }
+
   private _processChildDeclarations(astDeclaration: AstDeclaration, context: IProcessAstEntityContext): void {
     for (const childDeclaration of astDeclaration.children) {
       this._processDeclaration(childDeclaration, {
@@ -544,7 +558,11 @@ export class ApiModelGenerator {
     }
   }
 
-  private _processApiFunction(astDeclaration: AstDeclaration, context: IProcessAstEntityContext): void {
+  private _processApiFunction(
+    astDeclaration: AstDeclaration,
+    context: IProcessAstEntityContext,
+    altFunctionDeclaration?: ts.FunctionDeclaration
+  ): void {
     const { name, isExported, parentApiItem } = context;
 
     const overloadIndex: number = this._collector.getOverloadIndex(astDeclaration);
@@ -554,7 +572,7 @@ export class ApiModelGenerator {
 
     if (apiFunction === undefined) {
       const functionDeclaration: ts.FunctionDeclaration =
-        astDeclaration.declaration as ts.FunctionDeclaration;
+        altFunctionDeclaration ?? (astDeclaration.declaration as ts.FunctionDeclaration);
 
       const nodesToCapture: IExcerptBuilderNodeToCapture[] = [];
 

build-tests/api-extractor-scenarios/etc/defaultExportOfEntryPoint2/api-extractor-scenarios.api.json

@@ -173,27 +173,28 @@
       "preserveMemberOrder": false,
       "members": [
         {
-          "kind": "Variable",
-          "canonicalReference": "api-extractor-scenarios!defaultFunctionStatement:var",
+          "kind": "Function",
+          "canonicalReference": "api-extractor-scenarios!defaultFunctionStatement:function(1)",
           "docComment": "/**\n * @public\n */\n",
           "excerptTokens": [
             {
               "kind": "Content",
-              "text": "defaultFunctionStatement: "
+              "text": "defaultFunctionStatement: () => "
             },
             {
               "kind": "Content",
-              "text": "() => void"
+              "text": "void"
             }
           ],
           "fileUrlPath": "src/defaultExportOfEntryPoint2/index.ts",
-          "isReadonly": true,
-          "releaseTag": "Public",
-          "name": "defaultFunctionStatement",
-          "variableTypeTokenRange": {
+          "returnTypeTokenRange": {
             "startIndex": 1,
             "endIndex": 2
-          }
+          },
+          "releaseTag": "Public",
+          "overloadIndex": 1,
+          "parameters": [],
+          "name": "defaultFunctionStatement"
         }
       ]
     }

build-tests/api-extractor-scenarios/etc/spanSorting/api-extractor-scenarios.api.json

@@ -375,27 +375,45 @@
           "implementsTokenRanges": []
         },
         {
-          "kind": "Variable",
-          "canonicalReference": "api-extractor-scenarios!exampleD:var",
+          "kind": "Function",
+          "canonicalReference": "api-extractor-scenarios!exampleD:function(1)",
           "docComment": "/**\n * Outer description\n *\n * @public\n */\n",
           "excerptTokens": [
             {
               "kind": "Content",
-              "text": "exampleD: "
+              "text": "exampleD: (o: "
             },
             {
               "kind": "Content",
-              "text": "(o: {\n    a: number;\n    b(): string;\n}) => void"
+              "text": "{\n    a: number;\n    b(): string;\n}"
+            },
+            {
+              "kind": "Content",
+              "text": ") => "
+            },
+            {
+              "kind": "Content",
+              "text": "void"
             }
           ],
           "fileUrlPath": "src/spanSorting/index.ts",
-          "isReadonly": true,
+          "returnTypeTokenRange": {
+            "startIndex": 3,
+            "endIndex": 4
+          },
           "releaseTag": "Public",
-          "name": "exampleD",
-          "variableTypeTokenRange": {
-            "startIndex": 1,
-            "endIndex": 2
-          }
+          "overloadIndex": 1,
+          "parameters": [
+            {
+              "parameterName": "o",
+              "parameterTypeTokenRange": {
+                "startIndex": 1,
+                "endIndex": 2
+              },
+              "isOptional": false
+            }
+          ],
+          "name": "exampleD"
         }
       ]
     }

common/changes/@microsoft/api-extractor/bartvandenende-wm-api-extractor-arrow-func_2024-02-06-14-12.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@microsoft/api-extractor",
+      "comment": "Classify arrow functions as `function` kind in the doc model export.",
+      "type": "minor"
+    }
+  ],
+  "packageName": "@microsoft/api-extractor"
+}