Integer shift operators are not documented

[DartBot]

This issue was originally filed by ief...@unipro.ru

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What steps will reproduce the problem?
consider the following test:

main() {
  int val = 1 << 2147483647;
}

What is the expected output? What do you see instead?
Expected: not sure what, since behavior is not documented
Actual:
Unhandled exception:
NoSuchMethodException - receiver: '2147483647' function name: 'shlFromInt' arguments: [1]]
 0. Function: 'Object.noSuchMethod' url: 'bootstrap' line:356 col:3
 1. Function: 'IntegerImplementation.<<' url: 'bootstrap_impl' line:1505 col:28
 2. Function: '::main' url: '/home/iefremov/dart/co19/trunk/co19/tests/co19/src/LibTest/core/int/operator_lshift/int_operator_lshift_A01_t02.dart' line:17 col:15

The same works for operator >>

What version of the product are you using? On what operating system?
DartVM 3171

Please provide any additional information below.
co19 tests (see rev. 87):
LibTest/core/int/operator_lshift/int_operator_lshift_A01_t02.dart
LibTest/core/int/operator_rshift/int_operator_rshift_A01_t02.dart

[dgrove]

Assigning to Area=language to get the actual behavior specified.

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Added Area-Language label.

[dgrove]

Issue #1137 has been merged into this issue.

[dgrove]

From issue #1137, co19 tests that depend on this issue:
LibTest/core/int/operator_lshift/int_operator_lshift_A01_t02.dart
LibTest/core/int/operator_rshift/int_operator_rshift_A01_t02.dart
LibTest/core/int/operator_lshift/int_operator_lshift_A01_t03.dart
LibTest/core/int/operator_rshift/int_operator_rshift_A01_t03.dart

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Added Triaged label.
Changed the title to: "Integer shift operators are not documented".

[DartBot]

This comment was originally written by ief...@unipro.ru

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Actually, the spec says the following:

A shift expression of the form e1 op e2 is equivalent to the method invocation
e1.op(e2). A shift expression of the form super op e2 is equivalent to the method
invocation super.op(e2).

So it is probably a library issue: corresponding operators should be properly documented.

[floitschG]

I agree that this could be a library issue too.
Afaik we agreed on making 1 << X (for X big) throw an out of memory exception.
However 1 >> X should always work.

[gbracha]

Moving to libraries and assigning to Josh.

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Set owner to jjb@google.com.
Removed Area-Language label.
Added Area-Library, Accepted labels.

[lrhn]

I believe the implementation is working correctly now. The VM does throw an out-of-memory error when shifting by too much (when the representation would be too big to fit in the heap, or probably a little before).

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Set owner to @lrhn.
Added AssumedStale label.

[ghost]

Has the documentation be updated? See also co19 issue #129.

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cc @floitschG.

[lrhn]

The documentation doesn't mention memory overflows (nor should it, it's just another way to run out of memory, just as creating extremely large lists).
It does document what shifting does.
But there is a typo in it: the parameter is 'shiftAmount', but the example code uses 'shiftIndex'.