From 3a7077de4da997739f2617eac607a96e64c9a6c9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9e=20Kooi?= <renee@kooi.me>
Date: Mon, 12 Feb 2018 20:31:12 +0100
Subject: [PATCH 1/2] ignore require() calls inside already browserified
 bundles

If a function expression declares a `require` parameter, its body is not
analyzed for `require()` calls. This is mostly helpful for bundles that
were already browserified, `detective` will ignore the calls to
browser-pack's require runtime.
---
 index.js            | 13 +++++++++++++
 test/files/scope.js |  8 ++++++++
 test/scope.js       |  9 +++++++++
 3 files changed, 30 insertions(+)
 create mode 100644 test/files/scope.js
 create mode 100644 test/scope.js

diff --git a/index.js b/index.js
index 382d701a9..7313a348e 100644
--- a/index.js
+++ b/index.js
@@ -49,6 +49,7 @@ exports.find = function (src, opts) {
     function visit(node, st, c) {
         var hasRequire = wordRe.test(src.slice(node.start, node.end));
         if (!hasRequire) return;
+        if (redefinesRequire(node)) return;
         walk.base[node.type](node, st, c);
         if (node.type !== 'CallExpression') return;
         if (isRequire(node)) {
@@ -75,6 +76,18 @@ exports.find = function (src, opts) {
         Statement: visit,
         Expression: visit
     });
+
+    // Detect `require` redefinitions in function parameter lists, like
+    // in `[function(require,module,exports){` generated by browser-pack.
+    // This is a simple way to address the 99% case without doing full scope analysis
+    function redefinesRequire(node) {
+        if (node.type === 'FunctionExpression') {
+            return node.params.some(function (param) {
+                return param.type === 'Identifier' && param.name === word;
+            });
+        }
+        return false;
+    }
     
     return modules;
 };
diff --git a/test/files/scope.js b/test/files/scope.js
new file mode 100644
index 000000000..66ca0aed5
--- /dev/null
+++ b/test/files/scope.js
@@ -0,0 +1,8 @@
+(function(modules){
+    modules[1](function(i){return modules[i]()})
+})({1:[function (require,module,exports) {
+    require('./y')
+},{'./y':2}],2:function(require,module,exports){
+    console.log("abc")
+}})
+require('./z')
diff --git a/test/scope.js b/test/scope.js
new file mode 100644
index 000000000..e6b29bbb9
--- /dev/null
+++ b/test/scope.js
@@ -0,0 +1,9 @@
+var test = require('tap').test;
+var detective = require('../');
+var fs = require('fs');
+var src = fs.readFileSync(__dirname + '/files/scope.js');
+
+test('scope', function (t) {
+    t.plan(1);
+    t.deepEqual(detective(src), [ './z' ]);
+});

From c9bfb246119b76119e39ce7a5e43ece033eca079 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9e=20Kooi?= <renee@kooi.me>
Date: Fri, 13 Apr 2018 11:01:22 +0200
Subject: [PATCH 2/2] Be really strict about the kind of redefinition we expect

---
 index.js            | 20 +++++++++++---------
 test/files/scope.js |  6 +++++-
 test/scope.js       |  2 +-
 3 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/index.js b/index.js
index 7313a348e..70cfc704a 100644
--- a/index.js
+++ b/index.js
@@ -49,7 +49,7 @@ exports.find = function (src, opts) {
     function visit(node, st, c) {
         var hasRequire = wordRe.test(src.slice(node.start, node.end));
         if (!hasRequire) return;
-        if (redefinesRequire(node)) return;
+        if (isBundledDefinition(node)) return;
         walk.base[node.type](node, st, c);
         if (node.type !== 'CallExpression') return;
         if (isRequire(node)) {
@@ -78,15 +78,17 @@ exports.find = function (src, opts) {
     });
 
     // Detect `require` redefinitions in function parameter lists, like
-    // in `[function(require,module,exports){` generated by browser-pack.
+    // in `{0:[function(require,module,exports){` generated by browser-pack.
     // This is a simple way to address the 99% case without doing full scope analysis
-    function redefinesRequire(node) {
-        if (node.type === 'FunctionExpression') {
-            return node.params.some(function (param) {
-                return param.type === 'Identifier' && param.name === word;
-            });
-        }
-        return false;
+    function isBundledDefinition(node) {
+        if (node.type !== 'ObjectExpression') return false;
+        if (node.properties.length < 1) return false;
+        var arr = node.properties[0].value;
+        if (arr.type !== 'ArrayExpression') return false;
+        if (arr.elements.length < 2) return false;
+        if (arr.elements[0].type !== 'FunctionExpression') return false;
+        var fn = arr.elements[0];
+        return fn.params.length > 0 && fn.params[0].type === 'Identifier' && fn.params[0].name === word;
     }
     
     return modules;
diff --git a/test/files/scope.js b/test/files/scope.js
index 66ca0aed5..b94d787ac 100644
--- a/test/files/scope.js
+++ b/test/files/scope.js
@@ -1,8 +1,12 @@
 (function(modules){
     modules[1](function(i){return modules[i]()})
 })({1:[function (require,module,exports) {
-    require('./y')
+    require('./y') // inside a bundle; should not be detected
 },{'./y':2}],2:function(require,module,exports){
     console.log("abc")
 }})
+
+(function (require) {
+    require('./x'); // not inside a bundle; should be detected
+}(require)); // (because someone might do this)
 require('./z')
diff --git a/test/scope.js b/test/scope.js
index e6b29bbb9..3ffebca02 100644
--- a/test/scope.js
+++ b/test/scope.js
@@ -5,5 +5,5 @@ var src = fs.readFileSync(__dirname + '/files/scope.js');
 
 test('scope', function (t) {
     t.plan(1);
-    t.deepEqual(detective(src), [ './z' ]);
+    t.deepEqual(detective(src), [ './x', './z' ]);
 });