Suppress compiler warnings in dart:// code - the user is unable to take any action wrt these erro...

Suppress compiler warnings in dart:// code - the user is unable to take any action wrt these errors. They currently show up as exceptions in the editor's log.
Committed: https://code.google.com/p/dart/source/detail?r=3055

[devoncarew, 2012-01-04 18:14:24]

This CL addresses these exceptions in the log:

Could not find file for source
"dart://htmlimpl/src/DocumentFragmentWrappingImplementation.dart" (6): Local
variable 'last' is hiding 'METHOD last' at
DocumentFragmentWrappingImplementation.dart:FilteredElementList:110:11

[danrubel, 2012-01-04 18:32:28]

Before we suppress errors, perhaps we could pull together a CL that fixed the
problem in the libraries themselves? Or at least open an issue? If the CL is
denied or issue is marked wont-fix, then we can make this change.

On 2012/01/04 18:14:24, devoncarew wrote:
> This CL addresses these exceptions in the log:
> 
> Could not find file for source
> "dart://htmlimpl/src/DocumentFragmentWrappingImplementation.dart" (6): Local
> variable 'last' is hiding 'METHOD last' at
> DocumentFragmentWrappingImplementation.dart:FilteredElementList:110:11

[devoncarew, 2012-01-04 18:51:40]

Interestingly enough, while I see the source not found exceptions in people's
logs, I can't get the exceptions to reproduce on my machine. I'll open an issue
if I'm able to reproduce the exceptions.

[Brian Wilkerson, 2012-01-04 20:21:59]

> Before we suppress errors, perhaps we could pull together a CL that fixed the
> problem in the libraries themselves? Or at least open an issue? If the CL is
> denied or issue is marked wont-fix, then we can make this change.

I agree with Dan that we need to be careful about hiding these errors/warnings.
Before we can open an issue we need to understand whether the problem is in the
core library code or in the compiler(s). But I still like the idea of hiding
these from the user.

Note too that missing files are not the only source of core library errors. As
of this morning I am getting lots of warnings about type parameters (which I
think is a compiler bug and might be fixed by this point).

As I said yesterday, my only concern with hiding these errors from users is that
if user code fails to work because the core libraries are broken our users won't
have any way of discovering that that's the source of their problem.

> ...I can't get the exceptions to reproduce on my machine. I'll open an issue
> if I'm able to reproduce the exceptions.

I can reliably reproduce the problem on my machine if you want to take a look at
it. (Not the missing file error, but other compilation errors.)

http://codereview.chromium.org/9030024/diff/1/editor/tools/plugins/com.google...
File
editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/internal/builder/CompilerListener.java
(right):

http://codereview.chromium.org/9030024/diff/1/editor/tools/plugins/com.google...
editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/internal/builder/CompilerListener.java:137:
if (source != null && source.getUri().toString().startsWith("dart://")) {
If we do add this code I would at least like to add a debug option to turn the
logging back on. Perhaps something like

  if (source != nul && ... && !DartCoreDebug.SHOW_CORE_ERRORS) {

[devoncarew, 2012-01-05 18:49:17]

I filed a bug w/ the compiler warnings at:
http://code.google.com/p/dart/issues/detail?id=1060

I also added a DartCoreDebug.VERBOSE options flag, and log the core lib warnings
if that flag is set.

The main motivation for this change is that we're showing errors and warnings in
the Problems view that the user can't do anything about. It's probably pretty
frustrating for them, and I imagine causes them to think that they've done
something wrong. I totally agree that we should fix the underlying issue, and
log these core lib warnings ourselves so that we don't loose visibility of them.

[devoncarew, 2012-01-05 18:50:21]

http://codereview.chromium.org/9030024/diff/1/editor/tools/plugins/com.google...
File
editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/internal/builder/CompilerListener.java
(right):

http://codereview.chromium.org/9030024/diff/1/editor/tools/plugins/com.google...
editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/internal/builder/CompilerListener.java:137:
if (source != null && source.getUri().toString().startsWith("dart://")) {
On 2012/01/04 20:22:00, Brian Wilkerson wrote:
> If we do add this code I would at least like to add a debug option to turn the
> logging back on. Perhaps something like
> 
>   if (source != nul && ... && !DartCoreDebug.SHOW_CORE_ERRORS) {

Done.

[danrubel, 2012-01-06 03:54:51]

lgtm

[Brian Wilkerson, 2012-01-06 19:23:47]

LGTM