147438 2015-07-29 22:18:18 -0700 Web Inspector: hard to find callers that cause ES6 TypeErrors thrown during inspector initialization 2016-12-13 15:34:29 -0800 1 1 1 Unclassified WebKit Web Inspector 528+ (Nightly build) All All NEW InRadar P2 Normal --- 147066 1 burg webkit-unassigned ggaren inspector-bugzilla-changes jonowells saam webkit-bug-importer ysuzuki oldest_to_newest 1113298 0 burg 2015-07-29 22:18:18 -0700 I have run into the following situation: a code refactoring I made introduced a TypeError, thrown by a caller that erroneously invokes an ES6 class constructor during inspector initialization. Unfortunately, the only error shown (with logging to console by stderr) is: file:///Users/burg/repos/webkit-dev/WebKitBuild/Release/WebInspectorUI.framework/Resources/Views/DataGrid.js:28:16: CONSOLE ERROR TypeError: Cannot call a class constructor Currently, ConsoleClient only captures a call stack for console messages with the "trace" type. So, the console only displays the first frame from the uncaught exception. The check that throws a TypeError is directly emitted into the constructor bytecode stream, which is what's seen here. But it's really the caller (next call frame) that we care about. So this seems to mostly be a problem associated with new ES6 errors with mysterious source locations. I propose two possible fixes, which are not mutually exclusive: * omit the call frame that's currently reported, since it is misleading to a user who is trying to debug the invalid call. * always capture/log multiple stack frames for uncaught exceptions, just like ConsoleClient does for "trace" messages. I welcome your thoughts on this issue prior to writing code. 1113299 1 webkit-bug-importer 2015-07-29 22:18:33 -0700 <rdar://problem/22066390> 1113420 2 joepeck 2015-07-30 11:22:34 -0700 What I would probably do is remote debug the failed inspector with a known good inspector and then reload the failed inspector page. 1124260 3 260764 bburg 2015-09-08 09:41:09 -0700 Created attachment 260764 reduced test case 260764 2015-09-08 09:41:09 -0700 2015-09-08 09:41:09 -0700 reduced test case class-constructor-exception-first-call-frame.html text/html 516 bburg PCFkb2N0eXBlIGh0bWw+CjxodG1sPgo8Ym9keSBvbmxvYWQ9InJ1blRlc3QoKSI+CjxzY3JpcHQ+ CgpmdW5jdGlvbiBydW5UZXN0KCkKewogICAgY2xhc3MgRm9vIHsKICAgICAgICBjb25zdHJ1Y3Rv cigpIHsKICAgICAgICAgICAgCiAgICAgICAgfQogICAgfQoKICAgIGNsYXNzIEJhciBleHRlbmRz IEZvbyB7CiAgICAgICAgY29uc3RydWN0b3IoKSB7CiAgICAgICAgICAgIEZvby5jYWxsKG51bGwp OwogICAgICAgIH0KICAgIH0KCiAgICBmdW5jdGlvbiBsZXZlbF8xKCkgewogICAgICAgIGxldmVs XzIoKTsKICAgIH0KCiAgICBmdW5jdGlvbiBsZXZlbF8yKCkgewogICAgICAgIGxldmVsXzMoKTsK ICAgIH0KCiAgICBmdW5jdGlvbiBsZXZlbF8zKCkgewogICAgICAgIG5ldyBCYXI7CiAgICB9Cgog ICAgbGV2ZWxfMSgpOwp9Cgo8L3NjcmlwdD4KCjxwPlRvIHJlcHJvZHVjZSB0aGUgYnVnLCBvcGVu IHRoZSBXZWIgSW5zcGVjdG9yIGFuZCByZWxvYWQgdGhlIHBhZ2UuPC9wPgoKPC9ib2R5Pgo8L2h0 bWw+