test/javascript/couch_test_runner.js - couchdb - Git at Google

 // Licensed under the Apache License, Version 2.0 (the "License"); you may not
 // use this file except in compliance with the License. You may obtain a copy of
 // the License at
 //
 //   http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 // License for the specific language governing permissions and limitations under
 // the License.

 // *********************** Test Framework of Sorts ************************* //


 function loadScript(url) {
   // disallow loading remote URLs
   var re = /^[a-z0-9_]+(\/[a-z0-9_]+)*\.js#?$/;
   if (!re.test(url)) {
       throw "Not loading remote test scripts";
   }
   if (typeof document != "undefined") document.write('<script src="'+url+'"></script>');
 };

 function patchTest(fun) {
   var source = fun.toString();
   var output = "";
   var i = 0;
   var testMarker = "T(";
   while (i < source.length) {
     var testStart = source.indexOf(testMarker, i);
     if (testStart == -1) {
       output = output + source.substring(i, source.length);
       break;
     }
     var testEnd = source.indexOf(");", testStart);
     var testCode = source.substring(testStart + testMarker.length, testEnd);
     output += source.substring(i, testStart) + "T(" + testCode + "," + JSON.stringify(testCode);
     i = testEnd;
   }
   try {
     return eval("(" + output + ")");
   } catch (e) {
     return null;
   }
 }

 function runAllTests() {
   var rows = $("#tests tbody.content tr");
   $("td", rows).text("");
   $("td.status", rows).removeClass("error").removeClass("failure").removeClass("success").text("not run");
   var offset = 0;
   function runNext() {
     if (offset < rows.length) {
       var row = rows.get(offset);
       runTest($("th button", row).get(0), function() {
         offset += 1;
         setTimeout(runNext, 100);
       }, false, true);
     } else {
       saveTestReport();
     }
   }
   runNext();
 }

 var numFailures = 0;
 var currentRow = null;

 function runTest(button, callback, debug, noSave) {

   // offer to save admins
   if (currentRow != null) {
     alert("Can not run multiple tests simultaneously.");
     return;
   }
   var row = currentRow = $(button).parents("tr").get(0);
   $("td.status", row).removeClass("error").removeClass("failure").removeClass("success");
   $("td", row).text("");
   $("#toolbar li.current").text("Running: "+row.id);
   var testFun = couchTests[row.id];
   function run() {
     numFailures = 0;
     var start = new Date().getTime();
     try {
       if (debug == undefined || !debug) {
         testFun = patchTest(testFun) || testFun;
       }
       testFun(debug);
       var status = numFailures > 0 ? "failure" : "success";
     } catch (e) {
       var status = "error";
       if ($("td.details ol", row).length == 0) {
         $("<ol></ol>").appendTo($("td.details", row));
       }
       $("<li><b>Exception raised:</b> <code class='error'></code></li>")
         .find("code").text(JSON.stringify(e)).end()
         .appendTo($("td.details ol", row));
       if (debug) {
         currentRow = null;
         throw e;
       }
     }
     if ($("td.details ol", row).length) {
       $("<a href='#'>Run with debugger</a>").click(function() {
         runTest(this, undefined, true);
       }).prependTo($("td.details ol", row));
     }
     var duration = new Date().getTime() - start;
     $("td.status", row).removeClass("running").addClass(status).text(status);
     $("td.duration", row).text(duration + "ms");
     $("#toolbar li.current").text("Finished: "+row.id);
     updateTestsFooter();
     currentRow = null;
     if (callback) callback();
     if (!noSave) saveTestReport();
   }
   $("td.status", row).addClass("running").text("running…");
   setTimeout(run, 100);
 }

 function showSource(cell) {
   var name = $(cell).text();
   var win = window.open("", name, "width=700,height=500,resizable=yes,scrollbars=yes");
   win.document.location = "script/test/" + name + ".js";
 }

 var readyToRun;
 function setupAdminParty(fun) {
   if (readyToRun) {
     fun();
   } else {
     function removeAdmins(confs, doneFun) {
       // iterate through the config and remove current user last
       // current user is at front of list
       var remove = confs.pop();
       if (remove) {
         $.couch.config({
           success : function() {
             removeAdmins(confs, doneFun);
           }
         }, "admins", remove[0], null);
       } else {
         doneFun();
       }
     };
     $.couch.session({
       success : function(resp) {
         var userCtx = resp.userCtx;
         if (userCtx.name && userCtx.roles.indexOf("_admin") != -1) {
           // admin but not admin party. dialog offering to make admin party
           $.showDialog("dialog/_admin_party.html", {
             submit: function(data, callback) {
               $.couch.config({
                 success : function(conf) {
                   var meAdmin, adminConfs = [];
                   for (var name in conf) {
                     if (name == userCtx.name) {
                       meAdmin = [name, conf[name]];
                     } else {
                       adminConfs.push([name, conf[name]]);
                     }
                   }
                   adminConfs.unshift(meAdmin);
                   removeAdmins(adminConfs, function() {
                     callback();
                     $.futon.session.sidebar();
                     readyToRun = true;
                     setTimeout(fun, 500);
                   });
                 }
               }, "admins");
             }
           });
         } else if (userCtx.roles.indexOf("_admin") != -1) {
           // admin party!
           readyToRun = true;
           fun();
         } else {
           // not an admin
           alert("Error: You need to be an admin to run the tests.");
         };
       }
     });
   }
 };

 function updateTestsListing() {
   for (var name in couchTests) {
     var testFunction = couchTests[name];
     var row = $("<tr><th></th><td></td><td></td><td></td></tr>")
       .find("th").text(name).attr("title", "Show source").click(function() {
         showSource(this);
       }).end()
       .find("td:nth(0)").addClass("status").text("not run").end()
       .find("td:nth(1)").addClass("duration").end()
       .find("td:nth(2)").addClass("details").end();
     $("<button type='button' class='run' title='Run test'></button>").click(function() {
       this.blur();
       var self = this;
       // check for admin party
       setupAdminParty(function() {
         runTest(self);
       });
       return false;
     }).prependTo(row.find("th"));
     row.attr("id", name).appendTo("#tests tbody.content");
   }
   $("#tests tr").removeClass("odd").filter(":odd").addClass("odd");
   updateTestsFooter();
 }

 function updateTestsFooter() {
   var tests = $("#tests tbody.content tr td.status");
   var testsRun = tests.filter(".success, .error, .failure");
   var testsFailed = testsRun.not(".success");
   var totalDuration = 0;
   $("#tests tbody.content tr td.duration:contains('ms')").each(function() {
     var text = $(this).text();
     totalDuration += parseInt(text.substr(0, text.length - 2), 10);
   });
   $("#tests tbody.footer td").html("<span>"+testsRun.length + " of " + tests.length +
     " test(s) run, " + testsFailed.length + " failures (" +
     totalDuration + " ms)</span> ");
 }

 // make report and save to local db
 // display how many reports need replicating to the mothership
 // have button to replicate them

 function saveTestReport(report) {
   var report = makeTestReport();
   if (report) {
     var db = $.couch.db("test_suite_reports");
     var saveReport = function(db_info) {
       report.db = db_info;
       $.couch.info({success : function(node_info) {
         report.node = node_info;
         db.saveDoc(report);
       }});
     };
     var createDb = function() {
       db.create({success: function() {
         db.info({success:saveReport});
       }});
     };
     db.info({error: createDb, success:saveReport});
   }
 };

 function makeTestReport() {
   var report = {};
   report.summary = $("#tests tbody.footer td").text();
   report.platform = testPlatform();
   var date = new Date();
   report.timestamp = date.getTime();
   report.timezone = date.getTimezoneOffset();
   report.tests = [];
   $("#tests tbody.content tr").each(function() {
     var status = $("td.status", this).text();
     if (status != "not run") {
       var test = {};
       test.name = this.id;
       test.status = status;
       test.duration = parseInt($("td.duration", this).text());
       test.details = [];
       $("td.details li", this).each(function() {
         test.details.push($(this).text());
       });
       if (test.details.length == 0) {
         delete test.details;
       }
       report.tests.push(test);
     }
   });
   if (report.tests.length > 0) return report;
 };

 function testPlatform() {
   var b = $.browser;
   var bs = ["mozilla", "msie", "opera", "safari"];
   for (var i=0; i < bs.length; i++) {
     if (b[bs[i]]) {
       return {"browser" : bs[i], "version" : b.version};
     }
   };
   return {"browser" : "undetected"};
 }


 function reportTests() {
   // replicate the database to couchdb.couchdb.org
 }

 // Use T to perform a test that returns false on failure and if the test fails,
 // display the line that failed.
 // Example:
 // T(MyValue==1);
 function T(arg1, arg2, testName) {
   if (!arg1) {
     if (currentRow) {
       if ($("td.details ol", currentRow).length == 0) {
         $("<ol></ol>").appendTo($("td.details", currentRow));
       }
       var message = (arg2 != null ? arg2 : arg1).toString();
       $("<li><b>Assertion " + (testName ? "'" + testName + "'" : "") + " failed:</b> <code class='failure'></code></li>")
         .find("code").text(message).end()
         .appendTo($("td.details ol", currentRow));
     }
     numFailures += 1;
   }
 }

 function TIsnull(actual, testName) {
   T(actual === null, "expected 'null', got '"
     + repr(actual) + "'", testName);
 }

 function TEquals(expected, actual, testName) {
   T(equals(expected, actual), "expected '" + repr(expected) +
     "', got '" + repr(actual) + "'", testName);
 }

 function TNotEquals(expected, actual, testName) {
   T(notEquals(expected, actual), "expected != '" + repr(expected) +
     "', got '" + repr(actual) + "'", testName);
 }

 function TEqualsIgnoreCase(expected, actual, testName) {
   T(equals(expected.toUpperCase(), actual.toUpperCase()), "expected '" + repr(expected) +
     "', got '" + repr(actual) + "'", testName);
 }

 function equals(a,b) {
   if (a === b) return true;
   try {
     return repr(a) === repr(b);
   } catch (e) {
     return false;
   }
 }

 function notEquals(a,b) {
   if (a != b) return true;
   return false;
 }

 function repr(val) {
   if (val === undefined) {
     return null;
   } else if (val === null) {
     return "null";
   } else {
     return JSON.stringify(val);
   }
 }

 function makeDocs(start, end, templateDoc) {
   var templateDocSrc = templateDoc ? JSON.stringify(templateDoc) : "{}";
   if (end === undefined) {
     end = start;
     start = 0;
   }
   var docs = [];
   for (var i = start; i < end; i++) {
     var newDoc = eval("(" + templateDocSrc + ")");
     newDoc._id = (i).toString();
     newDoc.integer = i;
     newDoc.string = (i).toString();
     docs.push(newDoc);
   }
   return docs;
 }

 function run_on_modified_server(settings, fun) {
   var xhr = CouchDB.request("GET", "/_membership");
   var nodes = JSON.parse(xhr.responseText).all_nodes;
   try {
     // set the settings
     for(var i=0; i < settings.length; i++) {
       var s = settings[i];
       for (var n in nodes) {
         xhr = CouchDB.request("PUT", "/_node/" + nodes[n] + "/_config/" + s.section + "/" + s.key, {
           body: JSON.stringify(s.value),
           headers: {"X-Couch-Persist": "false"}
         });
         CouchDB.maybeThrowError(xhr);
         if (typeof s[nodes[n]] === 'undefined') {
           s[nodes[n]] = {};
         }
         s[nodes[n]] = xhr.responseText;
       }
     }
     // run the thing
     fun();
   } finally {
     // unset the settings
     for(var j=0; j < i; j++) {
       for (var n in nodes) {
         var s = settings[j];
         if(s[nodes[n]] == "\"\"\n") { // unset value
           CouchDB.request("DELETE", "/_node/" + nodes[n] + "/_config/" + s.section + "/" + s.key, {
             headers: {"X-Couch-Persist": "false"}
           });
         } else {
           CouchDB.request("PUT", "/_node/" + nodes[n] + "/_config/" + s.section + "/" + s.key, {
             body: s[nodes[n]],
             headers: {"X-Couch-Persist": "false"}
           });
         }
       }
     }
   }
 }

 function stringFun(fun) {
   var string = fun.toSource ? fun.toSource() : "(" + fun.toString() + ")";
   return string;
 }

 function waitForSuccess(fun, tag) {
   var start = new Date();
   while(true) {
     if (new Date() - start > 5000) {
       throw("timeout: "+tag);
     } else {
       try {
         fun();
         break;
       } catch (e) {}
       // sync http req allow async req to happen
       try {
         CouchDB.request("GET", "/test_suite_db/?tag="+encodeURIComponent(tag));
       } catch (e) {}
     }
   }
 }

 // legacy functions for CouchDB < 1.2.0
 // we keep them to make sure we keep BC
 CouchDB.user_prefix = "org.couchdb.user:";

 CouchDB.prepareUserDoc = function(user_doc, new_password) {
   user_doc._id = user_doc._id || CouchDB.user_prefix + user_doc.name;
   if (new_password) {
     user_doc.password = new_password;
   }
   user_doc.type = "user";
   if (!user_doc.roles) {
     user_doc.roles = [];
   }
   return user_doc;
 };

 function get_random_string() {
   return Math.random()
     .toString(36)
     .replace(/[^a-z]+/g, '')
     .substr(0, 8);
 }

 function get_random_db_name() {
   return "test_suite_db_" + get_random_string()
 }

 // for Heisenbug-prone spots: retry n times (e.g. quora not met immediately)
 // if the problem still persists afterwards, we need sth else (similar to e.g. webdriver)
 function retry_part(fct, n, duration) {
   n = n || 3;
   duration = (duration == undefined ? 100 : duration);
   for(var i=1; i<=n; i++){
     try {
       return fct();
     }catch(e){
       if(i<n){
         // wait
         sleep(duration);
       }else{
         throw e;
       }
     }
   }
 }

 function wait(ms) {
   sleep(ms);
 }
	// Licensed under the Apache License, Version 2.0 (the "License"); you may not
	// use this file except in compliance with the License. You may obtain a copy of
	// the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
	// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
	// License for the specific language governing permissions and limitations under
	// the License.

	// ********************* Test Framework of Sorts *********************** //


	function loadScript(url) {
	// disallow loading remote URLs
	var re = /^[a-z0-9_]+(\/[a-z0-9_]+)*\.js#?$/;
	if (!re.test(url)) {
	throw "Not loading remote test scripts";
	}
	if (typeof document != "undefined") document.write('<script src="'+url+'"></script>');
	};

	function patchTest(fun) {
	var source = fun.toString();
	var output = "";
	var i = 0;
	var testMarker = "T(";
	while (i < source.length) {
	var testStart = source.indexOf(testMarker, i);
	if (testStart == -1) {
	output = output + source.substring(i, source.length);
	break;
	}
	var testEnd = source.indexOf(");", testStart);
	var testCode = source.substring(testStart + testMarker.length, testEnd);
	output += source.substring(i, testStart) + "T(" + testCode + "," + JSON.stringify(testCode);
	i = testEnd;
	}
	try {
	return eval("(" + output + ")");
	} catch (e) {
	return null;
	}
	}

	function runAllTests() {
	var rows = $("#tests tbody.content tr");
	$("td", rows).text("");
	$("td.status", rows).removeClass("error").removeClass("failure").removeClass("success").text("not run");
	var offset = 0;
	function runNext() {
	if (offset < rows.length) {
	var row = rows.get(offset);
	runTest($("th button", row).get(0), function() {
	offset += 1;
	setTimeout(runNext, 100);
	}, false, true);
	} else {
	saveTestReport();
	}
	}
	runNext();
	}

	var numFailures = 0;
	var currentRow = null;

	function runTest(button, callback, debug, noSave) {

	// offer to save admins
	if (currentRow != null) {
	alert("Can not run multiple tests simultaneously.");
	return;
	}
	var row = currentRow = $(button).parents("tr").get(0);
	$("td.status", row).removeClass("error").removeClass("failure").removeClass("success");
	$("td", row).text("");
	$("#toolbar li.current").text("Running: "+row.id);
	var testFun = couchTests[row.id];
	function run() {
	numFailures = 0;
	var start = new Date().getTime();
	try {
	if (debug == undefined \|\| !debug) {
	testFun = patchTest(testFun) \|\| testFun;
	}
	testFun(debug);
	var status = numFailures > 0 ? "failure" : "success";
	} catch (e) {
	var status = "error";
	if ($("td.details ol", row).length == 0) {
	$("<ol></ol>").appendTo($("td.details", row));
	}
	$("<li><b>Exception raised:</b> <code class='error'></code></li>")
	.find("code").text(JSON.stringify(e)).end()
	.appendTo($("td.details ol", row));
	if (debug) {
	currentRow = null;
	throw e;
	}
	}
	if ($("td.details ol", row).length) {
	$("<a href='#'>Run with debugger</a>").click(function() {
	runTest(this, undefined, true);
	}).prependTo($("td.details ol", row));
	}
	var duration = new Date().getTime() - start;
	$("td.status", row).removeClass("running").addClass(status).text(status);
	$("td.duration", row).text(duration + "ms");
	$("#toolbar li.current").text("Finished: "+row.id);
	updateTestsFooter();
	currentRow = null;
	if (callback) callback();
	if (!noSave) saveTestReport();
	}
	$("td.status", row).addClass("running").text("running…");
	setTimeout(run, 100);
	}

	function showSource(cell) {
	var name = $(cell).text();
	var win = window.open("", name, "width=700,height=500,resizable=yes,scrollbars=yes");
	win.document.location = "script/test/" + name + ".js";
	}

	var readyToRun;
	function setupAdminParty(fun) {
	if (readyToRun) {
	fun();
	} else {
	function removeAdmins(confs, doneFun) {
	// iterate through the config and remove current user last
	// current user is at front of list
	var remove = confs.pop();
	if (remove) {
	$.couch.config({
	success : function() {
	removeAdmins(confs, doneFun);
	}
	}, "admins", remove[0], null);
	} else {
	doneFun();
	}
	};
	$.couch.session({
	success : function(resp) {
	var userCtx = resp.userCtx;
	if (userCtx.name && userCtx.roles.indexOf("_admin") != -1) {
	// admin but not admin party. dialog offering to make admin party
	$.showDialog("dialog/_admin_party.html", {
	submit: function(data, callback) {
	$.couch.config({
	success : function(conf) {
	var meAdmin, adminConfs = [];
	for (var name in conf) {
	if (name == userCtx.name) {
	meAdmin = [name, conf[name]];
	} else {
	adminConfs.push([name, conf[name]]);
	}
	}
	adminConfs.unshift(meAdmin);
	removeAdmins(adminConfs, function() {
	callback();
	$.futon.session.sidebar();
	readyToRun = true;
	setTimeout(fun, 500);
	});
	}
	}, "admins");
	}
	});
	} else if (userCtx.roles.indexOf("_admin") != -1) {
	// admin party!
	readyToRun = true;
	fun();
	} else {
	// not an admin
	alert("Error: You need to be an admin to run the tests.");
	};
	}
	});
	}
	};

	function updateTestsListing() {
	for (var name in couchTests) {
	var testFunction = couchTests[name];
	var row = $("<tr><th></th><td></td><td></td><td></td></tr>")
	.find("th").text(name).attr("title", "Show source").click(function() {
	showSource(this);
	}).end()
	.find("td:nth(0)").addClass("status").text("not run").end()
	.find("td:nth(1)").addClass("duration").end()
	.find("td:nth(2)").addClass("details").end();
	$("<button type='button' class='run' title='Run test'></button>").click(function() {
	this.blur();
	var self = this;
	// check for admin party
	setupAdminParty(function() {
	runTest(self);
	});
	return false;
	}).prependTo(row.find("th"));
	row.attr("id", name).appendTo("#tests tbody.content");
	}
	$("#tests tr").removeClass("odd").filter(":odd").addClass("odd");
	updateTestsFooter();
	}

	function updateTestsFooter() {
	var tests = $("#tests tbody.content tr td.status");
	var testsRun = tests.filter(".success, .error, .failure");
	var testsFailed = testsRun.not(".success");
	var totalDuration = 0;
	$("#tests tbody.content tr td.duration:contains('ms')").each(function() {
	var text = $(this).text();
	totalDuration += parseInt(text.substr(0, text.length - 2), 10);
	});
	$("#tests tbody.footer td").html("<span>"+testsRun.length + " of " + tests.length +
	" test(s) run, " + testsFailed.length + " failures (" +
	totalDuration + " ms)</span> ");
	}

	// make report and save to local db
	// display how many reports need replicating to the mothership
	// have button to replicate them

	function saveTestReport(report) {
	var report = makeTestReport();
	if (report) {
	var db = $.couch.db("test_suite_reports");
	var saveReport = function(db_info) {
	report.db = db_info;
	$.couch.info({success : function(node_info) {
	report.node = node_info;
	db.saveDoc(report);
	}});
	};
	var createDb = function() {
	db.create({success: function() {
	db.info({success:saveReport});
	}});
	};
	db.info({error: createDb, success:saveReport});
	}
	};

	function makeTestReport() {
	var report = {};
	report.summary = $("#tests tbody.footer td").text();
	report.platform = testPlatform();
	var date = new Date();
	report.timestamp = date.getTime();
	report.timezone = date.getTimezoneOffset();
	report.tests = [];
	$("#tests tbody.content tr").each(function() {
	var status = $("td.status", this).text();
	if (status != "not run") {
	var test = {};
	test.name = this.id;
	test.status = status;
	test.duration = parseInt($("td.duration", this).text());
	test.details = [];
	$("td.details li", this).each(function() {
	test.details.push($(this).text());
	});
	if (test.details.length == 0) {
	delete test.details;
	}
	report.tests.push(test);
	}
	});
	if (report.tests.length > 0) return report;
	};

	function testPlatform() {
	var b = $.browser;
	var bs = ["mozilla", "msie", "opera", "safari"];
	for (var i=0; i < bs.length; i++) {
	if (b[bs[i]]) {
	return {"browser" : bs[i], "version" : b.version};
	}
	};
	return {"browser" : "undetected"};
	}


	function reportTests() {
	// replicate the database to couchdb.couchdb.org
	}

	// Use T to perform a test that returns false on failure and if the test fails,
	// display the line that failed.
	// Example:
	// T(MyValue==1);
	function T(arg1, arg2, testName) {
	if (!arg1) {
	if (currentRow) {
	if ($("td.details ol", currentRow).length == 0) {
	$("<ol></ol>").appendTo($("td.details", currentRow));
	}
	var message = (arg2 != null ? arg2 : arg1).toString();
	$("<li><b>Assertion " + (testName ? "'" + testName + "'" : "") + " failed:</b> <code class='failure'></code></li>")
	.find("code").text(message).end()
	.appendTo($("td.details ol", currentRow));
	}
	numFailures += 1;
	}
	}

	function TIsnull(actual, testName) {
	T(actual === null, "expected 'null', got '"
	+ repr(actual) + "'", testName);
	}

	function TEquals(expected, actual, testName) {
	T(equals(expected, actual), "expected '" + repr(expected) +
	"', got '" + repr(actual) + "'", testName);
	}

	function TNotEquals(expected, actual, testName) {
	T(notEquals(expected, actual), "expected != '" + repr(expected) +
	"', got '" + repr(actual) + "'", testName);
	}

	function TEqualsIgnoreCase(expected, actual, testName) {
	T(equals(expected.toUpperCase(), actual.toUpperCase()), "expected '" + repr(expected) +
	"', got '" + repr(actual) + "'", testName);
	}

	function equals(a,b) {
	if (a === b) return true;
	try {
	return repr(a) === repr(b);
	} catch (e) {
	return false;
	}
	}

	function notEquals(a,b) {
	if (a != b) return true;
	return false;
	}

	function repr(val) {
	if (val === undefined) {
	return null;
	} else if (val === null) {
	return "null";
	} else {
	return JSON.stringify(val);
	}
	}

	function makeDocs(start, end, templateDoc) {
	var templateDocSrc = templateDoc ? JSON.stringify(templateDoc) : "{}";
	if (end === undefined) {
	end = start;
	start = 0;
	}
	var docs = [];
	for (var i = start; i < end; i++) {
	var newDoc = eval("(" + templateDocSrc + ")");
	newDoc._id = (i).toString();
	newDoc.integer = i;
	newDoc.string = (i).toString();
	docs.push(newDoc);
	}
	return docs;
	}

	function run_on_modified_server(settings, fun) {
	var xhr = CouchDB.request("GET", "/_membership");
	var nodes = JSON.parse(xhr.responseText).all_nodes;
	try {
	// set the settings
	for(var i=0; i < settings.length; i++) {
	var s = settings[i];
	for (var n in nodes) {
	xhr = CouchDB.request("PUT", "/_node/" + nodes[n] + "/_config/" + s.section + "/" + s.key, {
	body: JSON.stringify(s.value),
	headers: {"X-Couch-Persist": "false"}
	});
	CouchDB.maybeThrowError(xhr);
	if (typeof s[nodes[n]] === 'undefined') {
	s[nodes[n]] = {};
	}
	s[nodes[n]] = xhr.responseText;
	}
	}
	// run the thing
	fun();
	} finally {
	// unset the settings
	for(var j=0; j < i; j++) {
	for (var n in nodes) {
	var s = settings[j];
	if(s[nodes[n]] == "\"\"\n") { // unset value
	CouchDB.request("DELETE", "/_node/" + nodes[n] + "/_config/" + s.section + "/" + s.key, {
	headers: {"X-Couch-Persist": "false"}
	});
	} else {
	CouchDB.request("PUT", "/_node/" + nodes[n] + "/_config/" + s.section + "/" + s.key, {
	body: s[nodes[n]],
	headers: {"X-Couch-Persist": "false"}
	});
	}
	}
	}
	}
	}

	function stringFun(fun) {
	var string = fun.toSource ? fun.toSource() : "(" + fun.toString() + ")";
	return string;
	}

	function waitForSuccess(fun, tag) {
	var start = new Date();
	while(true) {
	if (new Date() - start > 5000) {
	throw("timeout: "+tag);
	} else {
	try {
	fun();
	break;
	} catch (e) {}
	// sync http req allow async req to happen
	try {
	CouchDB.request("GET", "/test_suite_db/?tag="+encodeURIComponent(tag));
	} catch (e) {}
	}
	}
	}

	// legacy functions for CouchDB < 1.2.0
	// we keep them to make sure we keep BC
	CouchDB.user_prefix = "org.couchdb.user:";

	CouchDB.prepareUserDoc = function(user_doc, new_password) {
	user_doc._id = user_doc._id \|\| CouchDB.user_prefix + user_doc.name;
	if (new_password) {
	user_doc.password = new_password;
	}
	user_doc.type = "user";
	if (!user_doc.roles) {
	user_doc.roles = [];
	}
	return user_doc;
	};

	function get_random_string() {
	return Math.random()
	.toString(36)
	.replace(/[^a-z]+/g, '')
	.substr(0, 8);
	}

	function get_random_db_name() {
	return "test_suite_db_" + get_random_string()
	}

	// for Heisenbug-prone spots: retry n times (e.g. quora not met immediately)
	// if the problem still persists afterwards, we need sth else (similar to e.g. webdriver)
	function retry_part(fct, n, duration) {
	n = n \|\| 3;
	duration = (duration == undefined ? 100 : duration);
	for(var i=1; i<=n; i++){
	try {
	return fct();
	}catch(e){
	if(i<n){
	// wait
	sleep(duration);
	}else{
	throw e;
	}
	}
	}
	}

	function wait(ms) {
	sleep(ms);
	}