--- /dev/null
+// taken from https://raw.githubusercontent.com/indexzero/npm/bd3cad01fbd3ab481d2f5da441b9eead16029123/test/tap/config-nerf-dart.js
+// originally written by Charlie Robbins, https://github.com/indexzero
+var test = require("tap").test
+var toNerfDart = require("../../lib/config/nerf-dart.js")
+
+function validNerfDart (uri, valid) {
+ if (!valid) valid = "//registry.npmjs.org/"
+ test(uri, function (t) {
+ t.equal(toNerfDart(uri), valid)
+ t.end()
+ })
+}
+
+validNerfDart("http://registry.npmjs.org")
+validNerfDart("http://registry.npmjs.org/some-package")
+validNerfDart("http://registry.npmjs.org/some-package?write=true")
+validNerfDart("http://user:pass@registry.npmjs.org/some-package?write=true")
+validNerfDart("http://registry.npmjs.org/#random-hash")
+validNerfDart("http://registry.npmjs.org/some-package#random-hash")
+
+validNerfDart(
+ "http://relative.couchapp.npm/design/-/rewrite/",
+ "//relative.couchapp.npm/design/-/rewrite/"
+)
+validNerfDart(
+ "http://relative.couchapp.npm:8080/design/-/rewrite/",
+ "//relative.couchapp.npm:8080/design/-/rewrite/"
+)
+validNerfDart(
+ "http://relative.couchapp.npm:8080/design/-/rewrite/some-package",
+ "//relative.couchapp.npm:8080/design/-/rewrite/"
+)