Previously, ternary expressions were emitted as:
condExpr ? trueCase : falseCase
However, this causes problems when ternary operations are nested. In
particular, a template expression of the form:
a?.b ? c : d
would have compiled to:
a == null ? null : a.b ? c : d
The ternary operator is right-associative, so that expression is interpreted
as:
a == null ? null : (a.b ? c : d)
when in reality left-associativity is desired in this particular instance:
(a == null ? null : a.b) ? c : d
This commit adds a check in the expression translator to detect such
left-associative usages of ternaries and to enforce such associativity with
parentheses when necessary.
A test is also added for the template type-checking expression translator,
to ensure it correctly produces right-associative expressions for ternaries
in the user's template.
Fixes#34087
PR Close#34221
718d7fe5fe