require() should work with `node --eval`.

with tests

Fix module path resolve bug.  Normally the module path is taken from
realpath(__filename) but with eval there is (of course) no filename

src/node.js

@@ -111,6 +111,7 @@ var module = (function () {
     this.children = [];
   };
 
+
   // Modules
 
   var debugLevel = parseInt(process.env["NODE_DEBUG"], 16);
@@ -186,6 +187,13 @@ var module = (function () {
       return [request, modulePaths];
     }
 
+    // with --eval, parent.id is not set and parent.filename is null
+    if (!parent || !parent.id || !parent.filename) {
+      // make require('./path/to/foo') work - normally the path is taken
+      // from realpath(__filename) but with eval there is no filename
+      return [request, ['.'].concat(modulePaths)];
+    }
+
     // Is the parent an index module?
     // We can assume the parent has a valid extension,
     // as it already has been accepted as a module.
@@ -302,8 +310,7 @@ var module = (function () {
         sandbox.global      = sandbox;
         sandbox.root        = root;
 
-        evals.Script.runInNewContext(content, sandbox, filename);
-
+        return evals.Script.runInNewContext(content, sandbox, filename);
       } else {
         debug('load root module');
         // root module
@@ -312,7 +319,8 @@ var module = (function () {
         global.__filename = filename;
         global.__dirname  = dirname;
         global.module     = self;
-        evals.Script.runInThisContext(content, filename);
+
+        return evals.Script.runInThisContext(content, filename);
       }
 
     } else {
@@ -325,7 +333,7 @@ var module = (function () {
       if (filename === process.argv[1] && global.v8debug) {
         global.v8debug.Debug.setBreakPoint(compiledWrapper, 0, 0);
       }
-      compiledWrapper.apply(self.exports, [self.exports, require, self, filename, dirname]);
+      return compiledWrapper.apply(self.exports, [self.exports, require, self, filename, dirname]);
     }
   };
 
@@ -362,6 +370,9 @@ var module = (function () {
   // bootstrap repl
   exports.requireRepl = function () { return loadModule("repl", "."); };
 
+  // export for --eval
+  exports.Module = Module;
+
   return exports;
 })();
 
@@ -588,8 +599,8 @@ if (process.argv[1]) {
 
 } else if (process._eval) {
   // -e, --eval
-    var indirectEval= eval; // so the eval happens in global scope.
-    if (process._eval) console.log(indirectEval(process._eval));
+  var rv = new module.Module()._compile('return eval(process._eval)', 'eval');
+  console.log(rv);
 } else {
   // REPL
   module.requireRepl().start();

test/simple/test-cli-eval.js

@@ -0,0 +1,28 @@
+assert = require('assert');
+child = require('child_process');
+
+nodejs = process.execPath;
+
+if (module.parent) {
+  // signal we've been loaded as a module
+  console.log('Loaded as a module, exiting with status code 42.');
+  process.exit(42);
+}
+
+// assert that the result of the final expression is written to stdout
+child.exec(nodejs + ' --eval \'1337; 42\'',
+  function(err, stdout, stderr) {
+    assert.equal(parseInt(stdout), 42);
+  });
+
+// assert that module loading works
+child.exec(nodejs + ' --eval \'require("' + __filename + '")\'',
+  function(status, stdout, stderr) {
+    assert.equal(status.code, 42);
+  });
+
+// module path resolve bug, regression test
+child.exec(nodejs + ' --eval \'require("./test/simple/test-cli-eval.js")\'',
+  function(status, stdout, stderr) {
+    assert.equal(status.code, 42);
+  });