Details
Bug
Major
Description
As a compatibility and convenience measure, ICEfaces extends the prototypes of native JS types with a variety of helper functions and shims for advanced ECMAscript features.
However the extend ends up overwriting functions that have existing native implementations. This is generally discouraged for a few of reasons, primarily that this has a global effect, and that the overwriting implementation may not provide the expected functionality to 3rd party scripts, or that the overwriting implementation is slower due to being evaluated JS versus native C JSVM code.
I encountered this issue when attempting to use Array.prototype.filter to filter a NodeList as recommended by MDN documentation and it broke due to our implementations assumptions. As higher-order JS techniques like this become more popular we run greater risk of being incompatible.
A naive change, if possible would be to make extend not overwrite. If extend is used with the expectation of overwriting throughout or code this may not be possible however. In that case we may need to alter the calls to extend prototypes to indicate explicitly not to overwrite.
However the extend ends up overwriting functions that have existing native implementations. This is generally discouraged for a few of reasons, primarily that this has a global effect, and that the overwriting implementation may not provide the expected functionality to 3rd party scripts, or that the overwriting implementation is slower due to being evaluated JS versus native C JSVM code.
I encountered this issue when attempting to use Array.prototype.filter to filter a NodeList as recommended by MDN documentation and it broke due to our implementations assumptions. As higher-order JS techniques like this become more popular we run greater risk of being incompatible.
A naive change, if possible would be to make extend not overwrite. If extend is used with the expectation of overwriting throughout or code this may not be possible however. In that case we may need to alter the calls to extend prototypes to indicate explicitly not to overwrite.
Issue Links
Activity
| Field | Original Value | New Value |
|---|---|---|
| Assignee | Nils Lundquist [ nils.lundquist ] |
| Repository | Revision | Date | User | Message |
| ICEsoft Public SVN Repository | #35644 | Wed May 29 14:43:01 MDT 2013 | nils.lundquist | Revert: |
| Files Changed | ||||
MODIFY
/icefaces3/trunk/icefaces/compat/core/src/main/javascript/prototype/prototype.js
|
| Assignee Priority | P1 [ 10010 ] |
| Repository | Revision | Date | User | Message |
| ICEsoft Public SVN Repository | #36971 | Tue Jul 16 12:14:11 MDT 2013 | nils.lundquist | |
| Files Changed | ||||
|
MODIFY
/icefaces3/trunk/icefaces/compat/core/src/main/javascript/prototype/prototype.js
|
| Repository | Revision | Date | User | Message |
| ICEsoft Public SVN Repository | #36972 | Tue Jul 16 12:16:28 MDT 2013 | nils.lundquist | Revert: Incompatibility with Prototype resolved with resolution of |
| Files Changed | ||||
|
MODIFY
/icemobile/trunk/icemobile/jsf/components/component/resources/org.icefaces.component.util/component.js
|
Revision #36971
Committed by nils.lundquist
5 minutes ago
ICE-9303 - Prevent Prototype from overwriting native implementations.
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Nils Lundquist
added a comment - Revision #36971
Committed by nils.lundquist
5 minutes ago
ICE-9303 - Prevent Prototype from overwriting native implementations.
| Status | Open [ 1 ] | Resolved [ 5 ] |
| Resolution | Fixed [ 1 ] |
| Repository | Revision | Date | User | Message |
| ICEsoft Public SVN Repository | #37009 | Wed Jul 17 17:44:32 MDT 2013 | nils.lundquist | |
| Files Changed | ||||
|
MODIFY
/icefaces3/trunk/icefaces/compat/core/src/main/javascript/prototype/prototype.js
|
| Fix Version/s | 4.0 [ 11382 ] |
| Status | Resolved [ 5 ] | Closed [ 6 ] |
I went on with modifying all occurrences of calls to Object.extend() in all compat scripts, adding a flag at the end to overwrite the properties in the destination object, and the regressions reported by QA seem to be solved. At least, when testing the component-showcase app, everything seems to work fine, including the issues with D&D and ice:selectInputText. Actually, only four files in the compat project make use of Object.extend(); they are extras.js, dragdrop,js, effect.js, and prototype.js. They are quite big, though. It seems like throughout the codebase, including the prototype library itself, the expected behaviour of Object.extend() is to overwrite properties with the same name. The online documentation hints at that idea:
http://prototypejs.org/doc/latest/language/Object/extend/index.html
This is not committed yet, but I'll keep it in a separate copy of the repository on my machine. I'll commit it after the 3.3-EE code freeze for further testing, unless otherwise instructed.