1 files changed, 63 insertions, 0 deletions
diff --git a/bench/get-cjs-deps.js b/bench/get-cjs-deps.js
new file mode 100644
index 000000000..b999a1c16
--- /dev/null
+++ b/bench/get-cjs-deps.js
@@ -0,0 +1,63 @@
+var fs = require('fs');
+
+// require('...') || exports[''] = ... || exports.asd = ... || module.exports = ...
+var cjsExportsRegEx = /(?:^\uFEFF?|[^$_a-zA-Z\xA0-\uFFFF.])(exports\s*(\[['"]|\.)|module(\.exports|\['exports'\]|\["exports"\])\s*(\[['"]|[=,\.]))/;
+// RegEx adjusted from https://github.com/jbrantly/yabble/blob/master/lib/yabble.js#L339
+var cjsRequireRegEx = /(?:^\uFEFF?|[^$_a-zA-Z\xA0-\uFFFF."'])require\s*\(\s*("[^"\\]*(?:\\.[^"\\]*)*"|'[^'\\]*(?:\\.[^'\\]*)*')\s*\)/g;
+var commentRegEx = /(^|[^\\])(\/\*([\s\S]*?)\*\/|([^:]|^)\/\/(.*)$)/mg;
+
+var stringRegEx = /("[^"\\\n\r]*(\\.[^"\\\n\r]*)*"|'[^'\\\n\r]*(\\.[^'\\\n\r]*)*')/g;
+function getCJSDeps(source) {
+  cjsRequireRegEx.lastIndex = commentRegEx.lastIndex = stringRegEx.lastIndex = 0;
+
+  var deps = [];
+
+  var match;
+
+  // track string and comment locations for unminified source    
+  var stringLocations = [], commentLocations = [];
+
+  function inLocation(locations, match) {
+    for (var i = 0; i < locations.length; i++)
+      if (locations[i][0] < match.index && locations[i][1] > match.index)
+        return true;
+    return false;
+  }
+
+  if (source.length / source.split('\n').length < 200) {
+    while (match = stringRegEx.exec(source))
+      stringLocations.push([match.index, match.index + match[0].length]);
+
+    // TODO: track template literals here before comments
+    
+    while (match = commentRegEx.exec(source)) {
+      // only track comments not starting in strings
+      if (!inLocation(stringLocations, match))
+        commentLocations.push([match.index + match[1].length, match.index + match[0].length - 1]);
+    }
+  }
+
+  while (match = cjsRequireRegEx.exec(source)) {
+    // ensure we're not within a string or comment location
+    if (!inLocation(stringLocations, match) && !inLocation(commentLocations, match)) {
+      var dep = match[1].substr(1, match[1].length - 2);
+      // skip cases like require('" + file + "')
+      if (dep.match(/"|'/))
+        continue;
+      // trailing slash requires are removed as they don't map mains in SystemJS
+      if (dep[dep.length - 1] == '/')
+        dep = dep.substr(0, dep.length - 1);
+      deps.push(dep);
+    }
+  }
+
+  return deps;
+}
+
+var cjs = fs.readFileSync('./cjs-sample/cjs.js').toString();
+
+var startTime = Date.now();
+for (var i = 0; i < 1000; i++)
+  getCJSDeps(cjs);
+console.log(Date.now() - startTime);
+