No warning given when self-assigment occurs

[DartBot]

This issue was originally filed by [email protected]

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What steps will reproduce the problem?

1. create a class with a member variable: int a
2. create a member method with a parameter: method_x(int a)
3. make an invalid (useless) assignment "a = a;" in that method

What is the expected output? What do you see instead?

I expect to get at least a warning because the code has no effect.
The code that should have been written would be "this.a = a;"

What version of the product are you using? On what operating system?
Dart Editor version 1.0.0_r30187 (DEV)
Dart SDK version 1.0.0.3_r30187
java version "1.7.0_45"
Linux 3.2.0-56-generic #­86-Ubuntu SMP x86_64 GNU/Linux

Please provide any additional information below.

[DartBot]

This comment was originally written by [email protected]

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A setter might have side-effects.

For example, if you do this in JavaScript:

    window.location = window.location;

It will reload the page.

Or if you do something like canvas.width = canvas.width, you'll clear the canvas.

Well, generally speaking, this is bad style, but it isn't necessarily a no-op.

[bwilkerson]

We can certainly add a hint for cases where no getter or setter is being invoked, which is probably the most common occurrence of the problem.

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Added this to the Later milestone.
Removed Type-Defect, Priority-Unassigned labels.
Added Type-Enhancement, Priority-Medium, Area-Analyzer, Triaged labels.

[DartBot]

This comment was originally written by [email protected]

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Ok, didn't consider side effects of setters.
As pointed out, maybe assignments that don't use getters/setters can be checked.
Will still be of use for avoiding a few bugs.

Thanks for the feedback.

[bwilkerson]

Added Analyzer-Hint label.

[kasperl]

Removed this from the Later milestone.
Added Oldschool-Milestone-Later label.

[kasperl]

Removed Oldschool-Milestone-Later label.

[srawlins]

I think the linter might already have a self-assignment lint? Maybe just for getters/setters?

[srawlins]

no_self_assignments