From c2f07ca4e230ac62828655fc4199d570910fe035 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Murias?= <pawelmurias@gmail.com>
Date: Fri, 12 Oct 2018 15:06:48 +0200
Subject: [PATCH] [js] Code evaluation changes to prevent context polution

---
 src/vm/js/Compiler.nqp        |  2 +-
 src/vm/js/nqp-runtime/core.js | 18 +++++++++++-------
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/src/vm/js/Compiler.nqp b/src/vm/js/Compiler.nqp
index 7d26517830..57f425bed1 100644
--- a/src/vm/js/Compiler.nqp
+++ b/src/vm/js/Compiler.nqp
@@ -1748,7 +1748,7 @@ class QAST::CompilerJS does DWIMYNameMangling does SerializeOnce {
             @setup.push("new nqp.EvalResult({$body.expr}, nqp.createArray(cuids))");
         }
 
-        @setup.unshift((!$instant ?? '' !! "module.exports = ") ~ "nqp.run({self.async}function() \{\n");
+        @setup.unshift((!$instant ?? '/* return */' !! "module.exports = ") ~ "nqp.run({self.async}function() \{\n");
         @setup.push("\});\n");
         Chunk.new($T_VOID, "", @setup);
     }
diff --git a/src/vm/js/nqp-runtime/core.js b/src/vm/js/nqp-runtime/core.js
index 8faf43edbf..16b44e41e4 100644
--- a/src/vm/js/nqp-runtime/core.js
+++ b/src/vm/js/nqp-runtime/core.js
@@ -661,7 +661,7 @@ function toJS(obj) {
 
 const nqp = require('./runtime.js');
 
-const Script = process.browser ? null : require('vm').Script;
+const vm = process.browser ? null : require('vm');
 
 const sourceMaps = {};
 const evaledP6Sources = {};
@@ -789,6 +789,11 @@ exports.buildSourceMap = new BuildSourceMap();
 
 
 class JavaScriptCompiler extends NQPObject {
+  $$fixupRun(code) {
+    const fixedUp = code.replace(/\/\*\s*return\s\*\/\s*nqp\.run/, 'return nqp.run');
+    return fixedUp;
+  }
+
   eval(ctx, _NAMED, self, code) {
     if (!(_NAMED !== null && _NAMED.hasOwnProperty('mapping'))) {
       return fromJS(eval(nqp.arg_s(ctx, code)));
@@ -824,7 +829,7 @@ class JavaScriptCompiler extends NQPObject {
       evaledP6Filenames[fakeFilename] = nqp.toStr(_NAMED.file, ctx);
     }
 
-    const script = new Script(preamble + codeStr, {filename: fakeFilename});
+    const compiled = vm.compileFunction(preamble + this.$$fixupRun(codeStr), [], {filename: fakeFilename});
 
     global.nqpModule = module;
 
@@ -835,19 +840,18 @@ class JavaScriptCompiler extends NQPObject {
       return require(path);
     };
 
-
-    const ret = fromJS(script.runInThisContext());
+    const ret = fromJS(compiled());
     global.nqpRequire = oldNqpRequire;
 
     return ret;
   }
 
   compile(ctx, _NAMED, self, code) {
-    const script = new Script(code);
+    const compiled = vm.compileFunction(this.$$fixupRun(code));
 
     const codeRef = new CodeRef();
     codeRef.$$call = function(ctx, _NAMED) {
-      return fromJS(script.runInThisContext());
+      return fromJS(compiled());
     };
     return codeRef;
   }
@@ -1613,7 +1617,7 @@ op.ctxouterskipthunks = function(ctx) {
   let outer = ctx.$$skipHandlers().$$outer;
 
   // FIXME - ctxs that don't have a codeRef
-  while (outer && outer.codeRef().staticCode.isThunk) {
+  while (outer && (outer.codeRef() && outer.codeRef().staticCode.isThunk)) {
     outer = outer.$$outer;
     if (outer) outer = outer.$$skipHandlers();
   }