fix: address PR feedback

Author: Brendan McKee

src/api.ts

@@ -1,5 +1,6 @@
 import { aws_apigateway } from "aws-cdk-lib";
 import { Construct } from "constructs";
+import { isParameterDecl } from ".";
 import { FunctionDecl, isFunctionDecl } from "./declaration";
 import { isErr } from "./error";
 import {
@@ -100,6 +101,11 @@ export abstract class BaseApiIntegration {
  * inference.
  */
 export class ApiIntegrations {
+  /**
+   * Identify subclasses as API integrations to the Functionless plugin
+   */
+  public static readonly FunctionlessType = "ApiIntegrations";
+
   /**
    * Create a {@link MockApiIntegration}.
    */
@@ -309,7 +315,7 @@ export class AwsApiIntegration<
     // TODO: resource is not the right scope, prevents adding 2 methods to the resource
     // because of the IAM roles created
     // should `this` be a Method?
-    const apiGwIntegration = integration!.apiGWVtl.makeIntegration(
+    const apiGwIntegration = integration!.apiGWVtl.createIntegration(
       resource,
       requestTemplate,
       integrationResponses
@@ -415,12 +421,12 @@ export function toVTL(
           }
         })
       );
-    } else if (isArgument(node)) {
-      return inner(node);
+    } else if (isArgument(node) && node.expr) {
+      return inner(node.expr);
     } else if (isPropAccessExpr(node)) {
       // ignore the function param name, we'll replace it with the VTL
       // mapping template inputs
-      const path = pathFromFunctionParameter(node)?.slice(1);
+      const [_, ...path] = pathFromFunctionParameter(node) ?? [];
 
       if (path) {
         if (location === "response") {
@@ -516,7 +522,7 @@ function validateFunctionDecl(a: any): FunctionDecl {
 function isFunctionParameter(node: FunctionlessNode): node is Identifier {
   if (!isIdentifier(node)) return false;
   const ref = node.lookup();
-  return ref?.kind === "ParameterDecl" && ref.parent?.kind === "FunctionDecl";
+  return isParameterDecl(ref) && isFunctionDecl(ref.parent);
 }
 
 /**
@@ -551,7 +557,7 @@ export interface ApiGatewayVtlIntegration {
   /**
    * Construct an API GW integration.
    */
-  makeIntegration: (
+  createIntegration: (
     scope: Construct,
     requestTemplate: string,
     responses: aws_apigateway.IntegrationResponse[]

src/checker.ts

@@ -1,6 +1,6 @@
 import * as ts from "typescript";
 import * as tsserver from "typescript/lib/tsserverlibrary";
-import { BaseApiIntegration } from "./api";
+import { ApiIntegrations, BaseApiIntegration } from "./api";
 import { AppsyncResolver } from "./appsync";
 import { EventBus, EventBusRule } from "./event-bridge";
 import { EventBusTransform } from "./event-bridge/transform";
@@ -225,16 +225,17 @@ export function makeFunctionlessChecker(
   function isApiIntegrationsStaticMethod(
     node: ts.Node
   ): node is ApiIntegrationsStaticMethodInterface {
-    const x =
+    return (
       ts.isCallExpression(node) &&
       ts.isPropertyAccessExpression(node.expression) &&
       (node.expression.name.text === "mock" ||
         node.expression.name.text == "aws") &&
       ts.isIdentifier(node.expression.expression) &&
-      // TODO: is this enough? should we grab the type and make sure it
-      // has FunctionlessKind?
-      node.expression.expression.text === "ApiIntegrations";
-    return x;
+      isFunctionlessClassOfKind(
+        node.expression.expression,
+        ApiIntegrations.FunctionlessType
+      )
+    );
   }
 
   function isApiIntegration(node: ts.Node): node is ApiIntegrationInterface {

src/compile.ts

@@ -582,26 +582,6 @@ export function compile(
         );
       }
 
-      function visitApiIntegrationMapperProp(
-        prop: ts.PropertyAssignment
-      ): ts.PropertyAssignment {
-        const { initializer } = prop;
-        if (
-          !ts.isFunctionExpression(initializer) &&
-          !ts.isArrowFunction(initializer)
-        ) {
-          throw new Error(
-            `Expected mapping property of an ApiIntegration to be a function. Found ${initializer.getText()}.`
-          );
-        }
-
-        return ts.factory.updatePropertyAssignment(
-          prop,
-          prop.name,
-          errorBoundary(() => toFunction("FunctionDecl", initializer))
-        );
-      }
-
       function visitApiIntegrationResponsesProp(
         prop: ts.PropertyAssignment
       ): ts.PropertyAssignment {
@@ -622,6 +602,25 @@ export function compile(
         );
       }
 
+      function visitApiIntegrationMapperProp(
+        prop: ts.PropertyAssignment
+      ): ts.PropertyAssignment {
+        const { initializer } = prop;
+        const toFunc = errorBoundary(() => {
+          if (
+            !ts.isFunctionExpression(initializer) &&
+            !ts.isArrowFunction(initializer)
+          ) {
+            throw new Error(
+              `Expected mapping property of an ApiIntegration to be a function. Found ${initializer.getText()}.`
+            );
+          }
+          return toFunction("FunctionDecl", initializer);
+        });
+
+        return ts.factory.updatePropertyAssignment(prop, prop.name, toFunc);
+      }
+
       function toExpr(
         node: ts.Node | undefined,
         scope: ts.Node

src/function.ts

@@ -131,7 +131,7 @@ abstract class FunctionBase<P, O>
     this.apiGWVtl = {
       prepareRequest: (obj) => obj,
 
-      makeIntegration: (_scope, requestTemplate, integrationResponses) => {
+      createIntegration: (_scope, requestTemplate, integrationResponses) => {
         return new aws_apigateway.LambdaIntegration(this.resource, {
           proxy: false,
           passthroughBehavior: aws_apigateway.PassthroughBehavior.NEVER,

src/step-function.ts

@@ -519,7 +519,7 @@ abstract class BaseStepFunction<
         };
       },
 
-      makeIntegration: (scope, requestTemplate, integrationResponses) => {
+      createIntegration: (scope, requestTemplate, integrationResponses) => {
         const credentialsRole = new aws_iam.Role(
           scope,
           "ApiGatewayIntegrationRole",

src/table.ts

@@ -316,7 +316,7 @@ export class Table<
           };
         },
 
-        makeIntegration: (api, template, integrationResponses) => {
+        createIntegration: (api, template, integrationResponses) => {
           const credentialsRole = new aws_iam.Role(
             api,
             "ApiGatewayIntegrationRole",