This reverts commit dc24c2bd34.
Turns out Chris fixed the build but when I was looking at the bots, his fix had
not been tested yet, so I thought the tree was still red and was trying to
revert to green.
This removes conformance of DarwinBool and ObjCBool to the Boolean protocol,
and makes the &&/||/! operators be concrete w.r.t. Bool instead of abstract
on Boolean.
This fixes some outstanding bugs w.r.t diagnostics, but exposes some cases
where an existing diagnostic is not great. I'll fix that in a later patch
(tracked by rdar://27391581).
change includes both the necessary protocol updates and the deprecation
warnings
suitable for migration. A future patch will remove the renamings and
make this
a hard error.
along with recent policy changes:
- For expression types that are not specifically handled, make sure to
produce a general "unused value" warning, catching a bunch of unused
values in the testsuite.
- For unused operator results, diagnose them as uses of the operator
instead of "calls".
- For calls, mutter the type of the result for greater specificity.
- For initializers, mutter the type of the initialized value.
- Look through OpenExistentialExpr's so we can handle protocol member
references propertly.
- Look through several other expressions so we handle @discardableResult
better.
as a failure to convert the individual operand, since the operator
is likely conceptually generic in some way and the choice of any
specific overload is probably arbitrary.
Since we now fall back to a better-informed diagnostics point, take
advantage of this to generate a specialized diagnostic when trying to
compare values of function type with ===.
Fixes rdar://25666129.
This reverts commit 073f427942,
i.e. it reapplies 35ba809fd0 with a
test fix to expect an extra note in one place.
as a failure to convert the individual operand, since the operator
is likely conceptually generic in some way and the choice of any
specific overload is probably arbitrary.
Since we now fall back to a better-informed diagnostics point, take
advantage of this to generate a specialized diagnostic when trying to
compare values of function type with ===.
Fixes rdar://25666129.
immediately discard as non-viable any declarations that cannot be
called due to argument-label mismatch.
This heuristic already existed, but it was badly out-of-date vs.
the current language rules on argument-passing. Change it to use
the standard argument matching algorithm.
This greatly reduces the number of overloads we consider for certain
kinds of expression, most importantly explicit initialization syntax
('T(x)'). Ordinary type-matching will quickly reject such calls,
but backtracking will discard this rejection. Thus this heuristic
can greatly decrease the total work done by the type-checker when
something else in the system is causing a combinatorial explosion.
The diagnostic changes in the test-suite seem acceptable to me.
Shout-out to Doug for pointing out multiple places where I didn't
need to reinvent the wheel.
immediately discard as non-viable any declarations that cannot be
called due to argument-label mismatch.
This heuristic already existed, but it was badly out-of-date vs.
the current language rules on argument-passing. Change it to use
the standard argument matching algorithm.
This greatly reduces the number of overloads we consider for certain
kinds of expression, most importantly explicit initialization syntax
('T(x)'). Ordinary type-matching will quickly reject such calls,
but backtracking will discard this rejection. Thus this heuristic
can greatly decrease the total work done by the type-checker when
something else in the system is causing a combinatorial explosion.
The diagnostic changes in the test-suite seem acceptable to me.
Shout-out to Doug for pointing out multiple places where I didn't
need to reinvent the wheel.
set where all members of the set produce the same type, produce a more
specific error.
Before:
t.swift:4:17: error: no '&&' candidates produce the expected contextual result type 'Int'
return a == b && 1 == 2
^
t.swift:4:17: note: produces result of type 'Bool'
return a == b && 1 == 2
^
after:
t.swift:4:17: error: '&&' produces 'Bool', not the expected contextual result type 'Int'
return a == b && 1 == 2
^
This improves the situation reported in https://twitter.com/_jlfischer/status/712337382175952896
In member ref expressions, if the base is optional, and the expected
expression result is either optional or unknown, suggest a fixit that
makes it into an optional chain expr rather than force unwrapping.
Since in many cases the actual fixit is emitted during diagnosis, and
thus, while type checking sub exprs with no contextual type specified
(so nothing to check for preferring optionality), we also need an
additional flag to pass down from FailureDiagnosis for whether we
prefer to fix as force unwrapping or optional chaining.
I attempted to do this same job via providing a convert type but
setting the ConvertTypeIsOnlyAHint flag on the type checker, but
unfortunately there are a lot of other moving parts that look at that
type, even if it is only supposed to be a hint, so an additional flag
to the CS ended up being cleaner.
Previously we would produce:
t.swift:3:3: error: binary operator '+=' cannot be applied to operands of type 'Int' and '_'
a += a + b
~ ^ ~~~~~
with a candidate set to follow. Now we properly match up the inout/lvalue type and produce
the following more specific diagnostic:
t.swift:3:10: error: cannot convert value of type 'UInt32' to expected argument type 'Int'
a += a + b
^
pointing the the "b".
