From b4ba327eddeb1d7312d1fd1778c807fb84b912e5 Mon Sep 17 00:00:00 2001
From: I Ketut Sandiarsa <ktutnik@gmail.com>
Date: Wed, 28 Dec 2022 08:00:47 +0800
Subject: [PATCH] fix(reflect): Fix issue when reflect function inside object

---
 packages/reflect/src/parser.ts                | 37 ++++++++++++-------
 .../__snapshots__/function.spec.ts.snap       | 19 ++++++++++
 tests/behavior/reflect/function.spec.ts       |  9 +++++
 3 files changed, 51 insertions(+), 14 deletions(-)

diff --git a/packages/reflect/src/parser.ts b/packages/reflect/src/parser.ts
index 5a9df8fa..53b9a903 100644
--- a/packages/reflect/src/parser.ts
+++ b/packages/reflect/src/parser.ts
@@ -58,29 +58,38 @@ function getNamesFromAst(nodes: any[]) {
     return nodes.map(x => getName(x)).filter((x): x is RootNode => !!x)
 }
 
-function getCode(fn: Class | Function) {
-    const syntaxReplacement = [
-        { pattern: /^class(\s*)extends\s*BaseClass\s*{\s*}/gm, replacement: "class DynamicClass extends Parent {}" },
-        { pattern: /^class(\s*){\s*}/gm, replacement: "class DynamicClass {}" },
-    ]
+function refineCode(fn: Class | Function, functionOnly = false) {
+    // some code may detected as invalid code, so its need to be fixed before parsed by acorn
     const code = fn.toString()
-    const exclude = syntaxReplacement.find(x => code.search(x.pattern) > -1)
-    if (exclude) {
-        return exclude.replacement
-    }
-    else
-        return code.replace("[native code]", "")
+
+    // for class created dynamically using reflect.create()
+    if(code.search(/^class(\s*)extends\s*BaseClass\s*{\s*}/gm) > -1) 
+        return "class DynamicClass extends Parent {}"
+
+    // for class created using reflect.class() but without base class 
+    if(code.search(/^class(\s*){\s*}/gm) > -1)
+        return "class DynamicClass {}"
+
+    // in case function inside object, it will cause error 
+    // example
+    // const obj = { fn(par1) {} }
+    // reflect(obj.fn)
+    if(functionOnly && code.search(/^([A-z0-9]+)\s*\((?:[^)(]+|\((?:[^)(]+|\([^)(]*\))*\))*\)/gm) > -1)
+        return `function ${code}`;
+    
+    // for the rest code, sometime its contain [native code], just remove it
+    return code.replace("[native code]", "")
 }
 
 function getMethodParameters(fn: Class, method: string) {
-    const body = getCode(fn)
+    const body = refineCode(fn)
     const ast = parse(body, { ecmaVersion: 2020 })
     const ctor = getNode(ast, x => x.type === "MethodDefinition" && x.kind === "method" && x.key.name === method)
     return getNamesFromAst(ctor ? (ctor as any).value.params : [])
 }
 
 function getConstructorParameters(fn: Class) {
-    const body = getCode(fn)
+    const body = refineCode(fn)
     const ast = parse(body, { ecmaVersion: 2020 })
     const ctor = getNode(ast, x => x.type === "MethodDefinition" && x.kind === "constructor")
     return getNamesFromAst(ctor ? (ctor as any).value.params : [])
@@ -88,7 +97,7 @@ function getConstructorParameters(fn: Class) {
 
 function getFunctionParameters(fn: Function) {
     try {
-        const body = getCode(fn)
+        const body = refineCode(fn, true)
         const ast: any = parse(body, { ecmaVersion: 2020 })
         const expBody = ast.body[0]
         if (expBody.type === "FunctionDeclaration")
diff --git a/tests/behavior/reflect/__snapshots__/function.spec.ts.snap b/tests/behavior/reflect/__snapshots__/function.spec.ts.snap
index 5f08945e..041ad3de 100644
--- a/tests/behavior/reflect/__snapshots__/function.spec.ts.snap
+++ b/tests/behavior/reflect/__snapshots__/function.spec.ts.snap
@@ -22,6 +22,25 @@ Object {
 }
 `;
 
+exports[`Reflect function Should able to reflect function inside object 1`] = `
+Object {
+  "kind": "Function",
+  "name": "fn",
+  "parameters": Array [
+    Object {
+      "decorators": Array [],
+      "fields": "par1",
+      "index": 0,
+      "kind": "Parameter",
+      "name": "par1",
+      "type": undefined,
+      "typeClassification": undefined,
+    },
+  ],
+  "returnType": undefined,
+}
+`;
+
 exports[`Reflect function Should able to reflect function parameter names 1`] = `
 Object {
   "kind": "Function",
diff --git a/tests/behavior/reflect/function.spec.ts b/tests/behavior/reflect/function.spec.ts
index eb9618dd..82eff236 100644
--- a/tests/behavior/reflect/function.spec.ts
+++ b/tests/behavior/reflect/function.spec.ts
@@ -26,6 +26,14 @@ describe("Reflect function", () => {
         const meta = reflect(myFunction)
         expect(meta).toMatchSnapshot()
     })
+
+    it("Should able to reflect function inside object", () => {
+        const obj = {
+            fn(par1:string) {}
+        }
+        const meta = reflect(obj.fn)
+        expect(meta).toMatchSnapshot()
+    })
 })
 
 describe("Reflect lambda function", () => {
@@ -53,4 +61,5 @@ describe("Reflect lambda function", () => {
         const meta = reflect(myFunction)
         expect(meta).toMatchSnapshot()
     })
+
 })
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