show at locations in errors

lib/render.js

@@ -81,6 +81,9 @@ function encodeResult (res, count) {
             output += inner + 'expected: ' + ex + '\n';
             output += inner + 'actual:   ' + ac + '\n';
         }
+        if (res.at) {
+            output += inner + 'at: ' + res.at + '\n';
+        }
         if (res.operator === 'error' && res.actual && res.actual.stack) {
             var lines = String(res.actual.stack).split('\n');
             output += inner + 'stack:\n';

lib/test.js

@@ -1,6 +1,7 @@
 var EventEmitter = require('events').EventEmitter;
 var deepEqual = require('deep-equal');
 var defined = require('defined');
+var path = require('path');
 
 module.exports = Test;
 
@@ -102,14 +103,37 @@ Test.prototype._assert = function assert (ok, opts) {
         name : defined(extra.message, opts.message, '(unnamed assert)'),
         operator : defined(extra.operator, opts.operator),
         actual : defined(extra.actual, opts.actual),
-        expected : defined(extra.expected, opts.expected)
+        expected : defined(extra.expected, opts.expected),
     };
     this._ok = Boolean(this._ok && ok);
 
     if (!ok) {
         res.error = defined(extra.error, opts.error, new Error(res.name));
     }
 
+    var e = new Error('exception');
+    var err = (e.stack || '').split('\n');
+    var dir = path.dirname(__dirname) + '/';
+
+    for (var i = 0; i < err.length; i++) {
+        var m = /^\s*\bat\s+(.+)/.exec(err[i]);
+        if (!m) continue;
+
+        var s = m[1].split(/\s+/);
+        var filem = /(\/[^:\s]+:(\d+)(?::(\d+))?)/.exec(s[1]);
+        if (!filem) continue;
+
+        if (filem[1].slice(0, dir.length) === dir) continue;
+
+        res.functionName = s[0];
+        res.file = filem[1];
+        res.line = Number(filem[2]);
+        if (filem[3]) res.column = filem[3];
+
+        res.at = m[1];
+        break;
+    }
+
     self.emit('result', res);
 
     if (self._plan === self.assertCount) {

package.json

@@ -1,6 +1,6 @@
 {
     "name" : "tape",
-    "version" : "0.1.5",
+    "version" : "0.2.0",
     "description" : "tap-producing test harness for node and browsers",
     "main" : "index.js",
     "bin" : {},