From 647ecefd71f0608cb80ad8bb7068da2c4d85151e Mon Sep 17 00:00:00 2001
From: Ayan Khan <khanayan_123@hotmail.com>
Date: Mon, 6 Nov 2023 23:52:30 -0500
Subject: [PATCH] fixes loader cyclical dependency bug by forgoing module
 wrapping of file and embedding file contents within the patch instead

---
 hook.js                                       |  46 +++-
 lib/ast-parse.js                              |   9 +
 lib/get-esm-exports.js                        | 203 +++++++++++++-----
 package.json                                  |   5 +-
 test/fixtures/a.mjs                           |   7 +
 test/fixtures/b.mjs                           |   6 +
 test/fixtures/export-types/declarations.mjs   |  11 +
 .../export-types/default-class-anon.mjs       |   1 +
 test/fixtures/export-types/default-class.mjs  |   1 +
 .../export-types/default-expression-array.mjs |   1 +
 .../export-types/default-expression-num.mjs   |   1 +
 .../default-expression-string.mjs             |   1 +
 .../export-types/default-function-anon.mjs    |   1 +
 .../export-types/default-function.mjs         |   1 +
 .../export-types/default-generator-anon.mjs   |   1 +
 .../export-types/default-generator.mjs        |   1 +
 test/fixtures/export-types/list.mjs           |  12 ++
 test/hook/declaration-exports.mjs             |  54 +++++
 test/hook/default-exports.mjs                 |  71 ++++++
 test/hook/list-exports.mjs                    |  33 +++
 test/other/cyclical-dependency.mjs            |  24 +++
 21 files changed, 429 insertions(+), 61 deletions(-)
 create mode 100644 lib/ast-parse.js
 create mode 100644 test/fixtures/a.mjs
 create mode 100644 test/fixtures/b.mjs
 create mode 100644 test/fixtures/export-types/declarations.mjs
 create mode 100644 test/fixtures/export-types/default-class-anon.mjs
 create mode 100644 test/fixtures/export-types/default-class.mjs
 create mode 100644 test/fixtures/export-types/default-expression-array.mjs
 create mode 100644 test/fixtures/export-types/default-expression-num.mjs
 create mode 100644 test/fixtures/export-types/default-expression-string.mjs
 create mode 100644 test/fixtures/export-types/default-function-anon.mjs
 create mode 100644 test/fixtures/export-types/default-function.mjs
 create mode 100644 test/fixtures/export-types/default-generator-anon.mjs
 create mode 100644 test/fixtures/export-types/default-generator.mjs
 create mode 100644 test/fixtures/export-types/list.mjs
 create mode 100644 test/hook/declaration-exports.mjs
 create mode 100644 test/hook/default-exports.mjs
 create mode 100644 test/hook/list-exports.mjs
 create mode 100644 test/other/cyclical-dependency.mjs

diff --git a/hook.js b/hook.js
index 3639fbf..d5ad87e 100644
--- a/hook.js
+++ b/hook.js
@@ -2,6 +2,9 @@
 //
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
 
+const fs = require('fs');
+const { fileURLToPath } = require('url')
+const astParse = require('./lib/ast-parse.js')
 const specifiers = new Map()
 const isWin = process.platform === "win32"
 
@@ -106,9 +109,9 @@ function createHook (meta) {
 
 
     specifiers.set(url.url, specifier)
-
+    
     return {
-      url: addIitm(url.url),
+      url: url.format !== 'module' ? addIitm(url.url) : url.url,
       shortCircuit: true,
       format: url.format
     }
@@ -119,7 +122,7 @@ function createHook (meta) {
     if (hasIitm(url)) {
       const realUrl = deleteIitm(url)
       const exportNames = await getExports(realUrl, context, parentGetSource)
-      return {
+      return { 
         source: `
 import { register } from '${iitmURL}'
 import * as namespace from ${JSON.stringify(url)}
@@ -134,6 +137,39 @@ set.${n} = (v) => {
 `).join('\n')}
 register(${JSON.stringify(realUrl)}, namespace, set, ${JSON.stringify(specifiers.get(realUrl))})
 `
+      } 
+    }
+    else if (context.format === 'module') {
+      let fileContents
+      try {
+        fileContents = fs.readFileSync(fileURLToPath(url), 'utf8')
+      } catch (parseError) {
+        console.error(`Had trouble reading file: ${fileContents}, got error: ${parseError}`);
+        return parentGetSource(url, context, parentGetSource)
+      }      
+      try {
+        const outPut = astParse(fileContents)
+        fileContents = outPut.code
+        exportAlias = outPut.exportAlias
+      } catch (parseError) {
+        console.error(`Tried AST parsing ${realPath}, got error: ${parseError}`);
+        return parentGetSource(url, context, parentGetSource)
+      }
+      const src = `${fileContents}
+import { register } from '${iitmURL}'
+const set = {}
+const namespace = {}
+${Object.entries(exportAlias).map(([key, value]) => `
+set.${key} = (v) => {
+  ${value} = v;
+  return true;
+};
+namespace.${key} = ${value}
+`).join('\n')}
+register(${JSON.stringify(url)}, namespace, set, ${JSON.stringify(specifiers.get(url))})
+`
+      return { 
+        source: src
       }
     }
 
@@ -142,7 +178,7 @@ register(${JSON.stringify(realUrl)}, namespace, set, ${JSON.stringify(specifiers
 
   // For Node.js 16.12.0 and higher.
   async function load (url, context, parentLoad) {
-    if (hasIitm(url)) {
+    if (hasIitm(url) || context.format === 'module') {
       const { source } = await getSource(url, context, parentLoad)
       return {
         source,
@@ -162,7 +198,7 @@ register(${JSON.stringify(realUrl)}, namespace, set, ${JSON.stringify(specifiers
       resolve,
       getSource,
       getFormat (url, context, parentGetFormat) {
-        if (hasIitm(url)) {
+        if (hasIitm(url) || context.format === 'module') {
           return {
             format: 'module'
           }
diff --git a/lib/ast-parse.js b/lib/ast-parse.js
new file mode 100644
index 0000000..0d50761
--- /dev/null
+++ b/lib/ast-parse.js
@@ -0,0 +1,9 @@
+'use strict'
+
+const getEsmExports = require('./get-esm-exports.js')
+
+function astParse(fileContents) {
+  return getEsmExports(fileContents, true)
+}
+
+module.exports = astParse
\ No newline at end of file
diff --git a/lib/get-esm-exports.js b/lib/get-esm-exports.js
index 3b4fa30..aa928b2 100644
--- a/lib/get-esm-exports.js
+++ b/lib/get-esm-exports.js
@@ -1,5 +1,6 @@
 'use strict'
 
+const recast = require('recast');
 const { Parser } = require('acorn')
 const { importAssertions } = require('acorn-import-assertions');
 
@@ -14,82 +15,176 @@ function warn (txt) {
   process.emitWarning(txt, 'get-esm-exports')
 }
 
-function getEsmExports (moduleStr) {
-  const exportedNames = new Set()
-  const tree = parser.parse(moduleStr, acornOpts)
-  for (const node of tree.body) {
-    if (!node.type.startsWith('Export')) continue
-    switch (node.type) {
-      case 'ExportNamedDeclaration':
-        if (node.declaration) {
-          parseDeclaration(node, exportedNames)
-        } else {
-          parseSpecifiers(node, exportedNames)
-        }
-        break
-      case 'ExportDefaultDeclaration':
-        exportedNames.add('default')
-        break
-      case 'ExportAllDeclaration':
-        if (node.exported) {
-          exportedNames.add(node.exported.name)
-        } else {
-          exportedNames.add('*')
-        }
-        break
-      default:
-        warn('unrecognized export type: ' + node.type)
+function getEsmExports(moduleStr, generate=false) {
+  const exportSpecifierNames = new Set();
+  const exportAlias = {}
+  const ast = recast.parse(moduleStr, {parser: {
+    parse(source) {
+      return parser.parse(source, acornOpts);
+    }
+  }})
+
+  recast.visit(ast, {
+    visitNode(path) {
+      const node = path.node;
+
+      if (!node.type.startsWith('Export')) {
+        this.traverse(path);
+        return;
+      }
+
+      switch (node.type) {
+        case 'ExportNamedDeclaration':
+          if (node.declaration) {
+            parseDeclaration(node.declaration, exportAlias);
+          } else {
+            parseSpecifiers(node.specifiers, exportAlias, exportSpecifierNames);
+          }
+          break;
+        case 'ExportDefaultDeclaration':
+          const iitmRenamedExport = 'iitmRenamedExport';
+          if (node.declaration.type === 'ObjectExpression' || node.declaration.type === 'ArrayExpression' || node.declaration.type === 'Literal') {
+            const variableDeclaration = {
+              type: 'VariableDeclaration',
+              kind: 'let',
+              declarations: [
+                {
+                  type: 'VariableDeclarator',
+                  id: {
+                    type: 'Identifier',
+                    name: iitmRenamedExport,
+                  },
+                  init: node.declaration,
+                },
+              ],
+            };
+            path.replace(variableDeclaration);
+            const newExportDefaultDeclaration = {
+              type: 'ExportDefaultDeclaration',
+              declaration: {
+                type: 'Identifier',
+                name: iitmRenamedExport,
+              },
+            };
+            path.insertAfter(newExportDefaultDeclaration);
+          } else {
+            node.declaration.id = { type: 'Identifier', name: iitmRenamedExport };
+          }
+          exportAlias['default'] = iitmRenamedExport;
+          break;
+        case 'ExportAllDeclaration':
+          const exportedName = node.exported ? node.exported.name : '*';
+          exportAlias[exportedName] = exportedName;
+          break;
+        case 'ExportSpecifier':
+          exportSpecifierNames.add(node.local.name)
+          if (node.exported?.name) {
+            exportAlias[node.exported.name] = node.local.name;
+          } else if (node.exported?.value) {
+            exportAlias[node.exported.value] = node.local.name;
+          } else {
+            warn('unrecognized specifier export: ' + node.exported);
+          }
+          break;
+        default:
+          warn('unrecognized export type: ' + node.type);
+      }
+      this.traverse(path);
+    },
+  });
+  if (exportSpecifierNames.size !== 0) {
+    convertExportSpecifierToLet(exportSpecifierNames, ast)
+  }
+
+  if (generate) {
+    return {
+      exportAlias: exportAlias,
+      code: recast.print(ast).code
     }
   }
-  return Array.from(exportedNames)
+
+  return Object.keys(exportAlias)
+}
+
+function convertExportSpecifierToLet(exportSpecifierNames, ast) {
+  recast.visit(ast, {
+    visitVariableDeclaration(path) {
+      const declaration = path.node;
+      if (declaration.kind === 'const') {
+        for (const declarator of declaration.declarations) {
+          const variableName = declarator.id.name;
+          if (exportSpecifierNames.has(variableName)) {
+            declaration.kind = 'let'; // Change 'const' to 'let'
+          }
+        }
+      }
+      this.traverse(path);
+    },
+  });
 }
 
-function parseDeclaration (node, exportedNames) {
-  switch (node.declaration.type) {
+function parseDeclaration(declaration, exportAlias) {
+  switch (declaration.type) {
     case 'FunctionDeclaration':
-      exportedNames.add(node.declaration.id.name)
-      break
+      exportAlias[declaration.id.name] = declaration.id.name
+      break;
     case 'VariableDeclaration':
-      for (const varDecl of node.declaration.declarations) {
-        parseVariableDeclaration(varDecl, exportedNames)
+      for (const varDecl of declaration.declarations) {
+        if (declaration.kind === 'const') {
+          declaration.kind = 'let';
+        }
+        parseVariableDeclaration(varDecl, exportAlias);
       }
-      break
+      break;
     case 'ClassDeclaration':
-      exportedNames.add(node.declaration.id.name)
-      break
+      exportAlias[declaration.id.name] = declaration.id.name
+      break;
     default:
-      warn('unknown declaration type: ' + node.delcaration.type)
+      warn('unknown declaration type: ' + declaration.type);
   }
 }
 
-function parseVariableDeclaration (node, exportedNames) {
-  switch (node.id.type) {
+function parseVariableDeclaration(varDecl, exportAlias) {
+  switch (varDecl.id.type) {
     case 'Identifier':
-      exportedNames.add(node.id.name)
-      break
+      exportAlias[varDecl.id.name] = varDecl.id.name
+      break;
     case 'ObjectPattern':
-      for (const prop of node.id.properties) {
-        exportedNames.add(prop.value.name)
+      for (const prop of varDecl.id.properties) {
+        exportAlias[prop.value.name] = prop.value.name
       }
-      break
+      break;
     case 'ArrayPattern':
-      for (const elem of node.id.elements) {
-        exportedNames.add(elem.name)
+      for (const elem of varDecl.id.elements) {
+        if (elem) {
+          exportAlias[elem.name] = elem.name
+        }
       }
-      break
+      break;
     default:
-      warn('unknown variable declaration type: ' + node.id.type)
+      warn('unknown variable declaration type: ' + varDecl.id.type);
   }
 }
 
-function parseSpecifiers (node, exportedNames) {
-  for (const specifier of node.specifiers) {
-    if (specifier.exported.type === 'Identifier') {
-      exportedNames.add(specifier.exported.name)
+function parseSpecifiers(specifiers, exportAlias, exportSpecifierNames) {
+  for (const specifier of specifiers) {
+    if (specifier.type === 'ExportSpecifier') {
+      exportSpecifierNames.add(specifier.local.name)
+      if (specifier.exported?.name) {
+        exportAlias[specifier.exported.name] = specifier.local.name;
+      } else if (specifier.exported?.value) {
+        exportAlias[specifier.exported.value] = specifier.local.name;
+      } else {
+        warn('unrecognized specifier export: ' + specifier);
+      }
+    }
+    else if (specifier.exported.type === 'Identifier') {
+      exportAlias[specifier.exported.name] = specifier.exported.name
     } else if (specifier.exported.type === 'Literal') {
-      exportedNames.add(specifier.exported.value)
-    } else {
-      warn('unrecognized specifier type: ' + specifier.exported.type)
+      exportAlias[specifier.exported.value] = specifier.exported.value
+    } 
+    else {
+      warn('unrecognized specifier type: ' + specifier.exported.type);
     }
   }
 }
diff --git a/package.json b/package.json
index 9af84f6..3b24d51 100644
--- a/package.json
+++ b/package.json
@@ -34,9 +34,10 @@
     "typescript": "^4.7.4"
   },
   "dependencies": {
-    "acorn": "^8.8.2",
+    "acorn": "^8.11.2",
     "acorn-import-assertions": "^1.9.0",
     "cjs-module-lexer": "^1.2.2",
-    "module-details-from-path": "^1.0.3"
+    "module-details-from-path": "^1.0.3",
+    "recast": "^0.23.4"
   }
 }
diff --git a/test/fixtures/a.mjs b/test/fixtures/a.mjs
new file mode 100644
index 0000000..c816a96
--- /dev/null
+++ b/test/fixtures/a.mjs
@@ -0,0 +1,7 @@
+import { testB } from './b.mjs';
+
+export function testA() {
+  console.log("testA");
+}
+
+testB();
\ No newline at end of file
diff --git a/test/fixtures/b.mjs b/test/fixtures/b.mjs
new file mode 100644
index 0000000..72b78e6
--- /dev/null
+++ b/test/fixtures/b.mjs
@@ -0,0 +1,6 @@
+import { testA } from './a.mjs';
+
+export function testB() {
+  console.log("testB");
+  testA();
+}
\ No newline at end of file
diff --git a/test/fixtures/export-types/declarations.mjs b/test/fixtures/export-types/declarations.mjs
new file mode 100644
index 0000000..bc92ca3
--- /dev/null
+++ b/test/fixtures/export-types/declarations.mjs
@@ -0,0 +1,11 @@
+const o = { name5: 1, name6: 1 };
+const array = [1, 1]
+
+// Exporting declarations
+export let name1 = 1, name2 = 1/*, … */; // also var
+export const name3 = 1, name4 = 1/*, … */; // also var, let
+export function functionName() { return 1 }
+export class ClassName { getFoo() { return 1 } }
+export function* generatorFunctionName() { return 1 }
+export const { name5, name6: bar } = o;
+export const [ name7, name8 ] = array;
diff --git a/test/fixtures/export-types/default-class-anon.mjs b/test/fixtures/export-types/default-class-anon.mjs
new file mode 100644
index 0000000..41984b3
--- /dev/null
+++ b/test/fixtures/export-types/default-class-anon.mjs
@@ -0,0 +1 @@
+export default class { getFoo() { return 1 } }
diff --git a/test/fixtures/export-types/default-class.mjs b/test/fixtures/export-types/default-class.mjs
new file mode 100644
index 0000000..207974b
--- /dev/null
+++ b/test/fixtures/export-types/default-class.mjs
@@ -0,0 +1 @@
+export default class ClassName { getFoo() { return 1 } }
diff --git a/test/fixtures/export-types/default-expression-array.mjs b/test/fixtures/export-types/default-expression-array.mjs
new file mode 100644
index 0000000..289d4e6
--- /dev/null
+++ b/test/fixtures/export-types/default-expression-array.mjs
@@ -0,0 +1 @@
+export default [1]
\ No newline at end of file
diff --git a/test/fixtures/export-types/default-expression-num.mjs b/test/fixtures/export-types/default-expression-num.mjs
new file mode 100644
index 0000000..55bb209
--- /dev/null
+++ b/test/fixtures/export-types/default-expression-num.mjs
@@ -0,0 +1 @@
+export default 1
\ No newline at end of file
diff --git a/test/fixtures/export-types/default-expression-string.mjs b/test/fixtures/export-types/default-expression-string.mjs
new file mode 100644
index 0000000..a7117c1
--- /dev/null
+++ b/test/fixtures/export-types/default-expression-string.mjs
@@ -0,0 +1 @@
+export default 'dog'
\ No newline at end of file
diff --git a/test/fixtures/export-types/default-function-anon.mjs b/test/fixtures/export-types/default-function-anon.mjs
new file mode 100644
index 0000000..86d3b3e
--- /dev/null
+++ b/test/fixtures/export-types/default-function-anon.mjs
@@ -0,0 +1 @@
+export default function () { return 1 }
\ No newline at end of file
diff --git a/test/fixtures/export-types/default-function.mjs b/test/fixtures/export-types/default-function.mjs
new file mode 100644
index 0000000..2e15809
--- /dev/null
+++ b/test/fixtures/export-types/default-function.mjs
@@ -0,0 +1 @@
+export default function functionName() { return 1 }
\ No newline at end of file
diff --git a/test/fixtures/export-types/default-generator-anon.mjs b/test/fixtures/export-types/default-generator-anon.mjs
new file mode 100644
index 0000000..417fbcc
--- /dev/null
+++ b/test/fixtures/export-types/default-generator-anon.mjs
@@ -0,0 +1 @@
+export default function* () { return 1 }
\ No newline at end of file
diff --git a/test/fixtures/export-types/default-generator.mjs b/test/fixtures/export-types/default-generator.mjs
new file mode 100644
index 0000000..1a4f33b
--- /dev/null
+++ b/test/fixtures/export-types/default-generator.mjs
@@ -0,0 +1 @@
+export default function* generatorFunctionName() { return 1 }
\ No newline at end of file
diff --git a/test/fixtures/export-types/list.mjs b/test/fixtures/export-types/list.mjs
new file mode 100644
index 0000000..512a87c
--- /dev/null
+++ b/test/fixtures/export-types/list.mjs
@@ -0,0 +1,12 @@
+// Export list
+const name1 = 1
+const name2 = 1
+const name5 = 1
+const variable1 = 1
+const variable2 = 1
+const variable3 = 1
+const name6 = 1
+export { name1, name2 };
+export { variable1 as name3, variable2 as name4, /* …, */ name5 };
+export { variable3 as "name" };
+export { name6 as default /*, … */ };
diff --git a/test/hook/declaration-exports.mjs b/test/hook/declaration-exports.mjs
new file mode 100644
index 0000000..734328e
--- /dev/null
+++ b/test/hook/declaration-exports.mjs
@@ -0,0 +1,54 @@
+// Unless explicitly stated otherwise all files in this repository are licensed under the Apache 2.0 License.
+//
+// This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
+
+import Hook from '../../index.js'
+import { name1 as n1,
+   name2 as n2, 
+   name3 as n3, 
+   name4 as n4, 
+   functionName as fn, 
+   ClassName as cn, 
+   generatorFunctionName as gfn, 
+   name5 as n5, 
+   bar as n6, 
+   name7 as n7, 
+   name8 as n8
+  } from '../fixtures/export-types/declarations.mjs'
+import { strictEqual } from 'assert'
+
+Hook((exports, name) => {
+  if (name.match(/declarations\.m?js/)) {
+    exports.name1 += 1
+    exports.name2 += 1
+    exports.name3 += 1
+    exports.name4 += 1
+    const orig = exports.functionName
+    exports.functionName = function () {
+      return orig() + 1
+    }
+    exports.ClassName.prototype.getFoo = function () {
+      return 2
+    }
+    const orig2 = exports.generatorFunctionName
+    exports.generatorFunctionName = function* () {
+      return orig2().next().value + 1
+    }
+    exports.name5 += 1
+    exports.bar += 1
+    exports.name7 += 1
+    exports.name8 += 1
+  }
+})
+
+strictEqual(n1, 2)
+strictEqual(n2, 2)
+strictEqual(n3, 2)
+strictEqual(n4, 2)
+strictEqual(fn(), 2)
+strictEqual(new cn().getFoo(), 2)
+strictEqual(gfn().next().value, 2)
+strictEqual(n5, 2)
+strictEqual(n6, 2)
+strictEqual(n7, 2)
+strictEqual(n8, 2)
diff --git a/test/hook/default-exports.mjs b/test/hook/default-exports.mjs
new file mode 100644
index 0000000..fd417fb
--- /dev/null
+++ b/test/hook/default-exports.mjs
@@ -0,0 +1,71 @@
+// Unless explicitly stated otherwise all files in this repository are licensed under the Apache 2.0 License.
+//
+// This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
+
+import Hook from '../../index.js'
+import a from '../fixtures/export-types/default-expression-array.mjs'
+import n from '../fixtures/export-types/default-expression-num.mjs'
+import s from '../fixtures/export-types/default-expression-string.mjs'
+import fn from '../fixtures/export-types/default-function.mjs'
+import cn from '../fixtures/export-types/default-class.mjs'
+import gfn from '../fixtures/export-types/default-generator.mjs'
+import afn from '../fixtures/export-types/default-function-anon.mjs'
+import acn from '../fixtures/export-types/default-class-anon.mjs'
+import agfn from '../fixtures/export-types/default-generator-anon.mjs'
+import { strictEqual } from 'assert'
+
+Hook((exports, name) => {
+  if (name.match(/default-expression-array\.m?js/)) {
+    exports.default[0] += 1
+  } else if (name.match(/default-expression-num\.m?js/)) {
+    exports.default += 1
+  }
+  else if (name.match(/default-expression-string\.m?js/)) {
+    exports.default += 'dawg'
+  }
+  else if (name.match(/default-function\.m?js/)) {
+    const orig = exports.default
+    exports.default = function () {
+      return orig() + 1
+    }
+  }
+  else if (name.match(/default-class\.m?js/)) {
+    exports.default.prototype.getFoo = function () {
+      return 2
+    }
+  }
+  else if (name.match(/default-generator\.m?js/)) {
+    const orig2 = exports.default
+    exports.default = function* () {
+      return orig2().next().value + 1
+    }
+  }
+  else if (name.match(/default-function-anon\.m?js/)) {
+    const orig = exports.default
+    exports.default = function () {
+      return orig() + 1
+    }
+  }
+  else if (name.match(/default-class-anon\.m?js/)) {
+    exports.default.prototype.getFoo = function () {
+      return 2
+    }
+  }
+  else if (name.match(/default-generator-anon\.m?js/)) {
+    const orig2 = exports.default
+    exports.default = function* () {
+      return orig2().next().value + 1
+    }
+  }
+})
+
+strictEqual(a[0], 2)
+strictEqual(fn(), 2)
+strictEqual(new cn().getFoo(), 2)
+strictEqual(gfn().next().value, 2)
+strictEqual(afn(), 2)
+strictEqual(new acn().getFoo(), 2)
+strictEqual(agfn().next().value, 2)
+// the below tests won't work because literal default exports are static
+// strictEqual(n, 2)
+// strictEqual(s, 'dogdawg')
diff --git a/test/hook/list-exports.mjs b/test/hook/list-exports.mjs
new file mode 100644
index 0000000..f181471
--- /dev/null
+++ b/test/hook/list-exports.mjs
@@ -0,0 +1,33 @@
+// Unless explicitly stated otherwise all files in this repository are licensed under the Apache 2.0 License.
+//
+// This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
+
+import Hook from '../../index.js'
+import n, { name1 as n1,
+   name2 as n2, 
+   name3 as n3, 
+   name4 as n4, 
+   name5 as n5, 
+   "name" as n6,
+  } from '../fixtures/export-types/list.mjs'
+import { strictEqual } from 'assert'
+
+Hook((exports, name) => {
+  if (name.match(/list\.m?js/)) {
+    exports.name1 += 1
+    exports.name2 += 1
+    exports.name3 += 1
+    exports.name4 += 1
+    exports.name5 += 1
+    exports.name += 1
+    exports.default += 1
+  }
+})
+
+strictEqual(n1, 2)
+strictEqual(n2, 2)
+strictEqual(n3, 2)
+strictEqual(n4, 2)
+strictEqual(n5, 2)
+strictEqual(n6, 2)
+strictEqual(n, 2)
diff --git a/test/other/cyclical-dependency.mjs b/test/other/cyclical-dependency.mjs
new file mode 100644
index 0000000..ebb163b
--- /dev/null
+++ b/test/other/cyclical-dependency.mjs
@@ -0,0 +1,24 @@
+// Unless explicitly stated otherwise all files in this repository are licensed under the Apache 2.0 License.
+//
+// This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
+
+import { spawn } from 'child_process';
+import { strictEqual } from 'assert';
+
+const nodeProcess = spawn('node', ['--loader', './hook.mjs', './test/fixtures/a.mjs']);
+const expectedOutput = 'testB\ntestA'
+let stdout = '';
+let stderr = '';
+
+nodeProcess.stdout.on('data', (data) => {
+  stdout += data.toString();
+});
+
+nodeProcess.stderr.on('data', (data) => {
+  stderr += data.toString();
+});
+
+nodeProcess.on('close', (code) => {
+  strictEqual(stderr, '', 'There should be no errors on stderr');
+  strictEqual(stdout.trim(), expectedOutput, 'The stdout should match the expected output');
+});