eclipse-aascw / aas-core-codegen / 41430932088

90%

Build Type

push

github

Committed by web-flow

Commit Message

Resolve negative indices at run time (#877)

In C++, C#, Java and Go, a negative list index known only at run time
was not counted from the back as in Python, and C++ ``xs[-1]`` on an
empty list was undefined behavior via ``.back()``. We now route all
list and JSON-array indices, literals included, through a per-target
helper which resolves a negative index and throws when out of range
so that the behavior in all targets is equal to that of Python:

* C++: ``common::At(xs, i)``,
* C#: ``Common.ListHelpers.At(xs, i)`` and ``SetAt(xs, i, v)``,
* Java: ``ListHelpers.at(xs, i)`` and ``ListHelpers.setAt(xs, i, v)``,
* Go: ``ourcommon.At(xs, i)`` and ``*ourcommon.PointerAt(xs, i) = v``.

Go writes go through a pointer since Go can not infer ``T`` in
``SetAt[T]([]T, int64, T)`` for a ``*Class`` written into an
``[]IClass``. TypeScript ``OurCommon.at`` now throws a ``RangeError``
instead of returning ``undefined``. The helpers are generated only if
the meta-model indexes a list.

We test reads and writes at negative run-time indices in the common
meta-model ``int_length_interplay``.

Coverage Stats

102 of 113 new or added lines in 9 files covered. (90.27%)

3 existing lines in 2 files now uncovered.

47028 of 52056 relevant lines covered (90.34%)

2.71 hits per line