Parameters (to methods, initializers, accessors, subscripts, etc) have always been represented
as Pattern's (of a particular sort), stemming from an early design direction that was abandoned.
Being built on top of patterns leads to patterns being overly complicated (e.g. tuple patterns
have to have varargs and default parameters) and make working on parameter lists complicated
and error prone. This might have been ok in 2015, but there is no way we can live like this in
2016.
Instead of using Patterns, carve out a new ParameterList and Parameter type to represent all the
parameter specific stuff. This simplifies many things and allows a lot of simplifications.
Unfortunately, I wasn't able to do this very incrementally, so this is a huge patch. The good
news is that it erases a ton of code, and the technical debt that went with it. Ignoring test
suite changes, we have:
77 files changed, 2359 insertions(+), 3221 deletions(-)
This patch also makes a bunch of wierd things dead, but I'll sweep those out in follow-on
patches.
Fixes <rdar://problem/22846558> No code completions in Foo( when Foo has error type
Fixes <rdar://problem/24026538> Slight regression in generated header, which I filed to go with 3a23d75.
Fixes an overloading bug involving default arguments and curried functions (see the diff to
Constraints/diagnostics.swift, which we now correctly accept).
Fixes cases where problems with parameters would get emitted multiple times, e.g. in the
test/Parse/subscripting.swift testcase.
The source range for ParamDecl now includes its type, which permutes some of the IDE / SourceModel tests
(for the better, I think).
Eliminates the bogus "type annotation missing in pattern" error message when a type isn't
specified for a parameter (see test/decl/func/functions.swift).
This now consistently parenthesizes argument lists in function types, which leads to many diffs in the
SILGen tests among others.
This does break the "sibling indentation" test in SourceKit/CodeFormat/indent-sibling.swift, and
I haven't been able to figure it out. Given that this is experimental functionality anyway,
I'm just XFAILing the test for now. i'll look at it separately from this mongo diff.
mode (take 2)
Allow untyped placeholder to take arbitrary type, but default to Void.
Add _undefined<T>() function, which is like fatalError() but has
arbitrary return type. In playground mode, merely warn about outstanding
placeholders instead of erroring out, and transform placeholders into
calls to _undefined(). This way, code with outstanding placeholders will
only crash when it attempts to evaluate such placeholders.
When generating constraints for an iterated sequence of type T, emit
T convertible to $T1
$T1 conforms to SequenceType
instead of
T convertible to SequenceType
This ensures that an untyped placeholder in for-each sequence position
doesn't get inferred to have type SequenceType. (The conversion is still
necessary because the sequence may have IUO type.) The new constraint
system precipitates changes in CSSimplify and CSDiag, and ends up fixing
18741539 along the way.
(NOTE: There is a small regression in diagnosis of issues like the
following:
class C {}
class D: C {}
func f(a: [C]!) { for _: D in a {} }
It complains that [C]! doesn't conform to SequenceType when it should be
complaining that C is not convertible to D.)
<rdar://problem/21167372>
(Originally Swift SVN r31481)
This fixes the crash in sr-114. Adding constraints for the invalid operator decl means constraining to the error type, which fails an
assertion later on while binding an overload choice. In all the normal function/method overload choice cases, if the decl is invalid
that choice gets skipped (never generated), so this is just another case of the existing way of doing things
Constraint generator likes the input AST to be not type-checked yet. However,
in code completion, we usually feed CSGen a (at least partially)
type-checked AST to infer the types of unresolved members, which
may lead to assertion failures. So we override the asserted method in
the code completion part to avoid explosions.
Swift SVN r32732
This allows us to start code-completing infix operators in postfix
expressions. As a first step, this patch only handles completing
against the immediate LHS (so for example 1 == 1 <here> doesn't suggest
boolean operators yet).
The next step is to feed the leading sequence expression from the parser
in so we can consider how the operator being completed fits into the
whole sequence expression.
For rdar://problem/22460167
Swift SVN r32465
When completing type members, teach the code completion engine to
transform the archetypes appearing in code completion results to the
actual types. NFC
Swift SVN r31628
When users invoke code completion at an argument position, we suggest argument names,
if required however not specified, or a list of argument values. These values are annotated
with their type relation to the expected argument types, so that
Xcode can prioritize those values that apply over those that do not.
This also fixes: rdar://21727063
Swift SVN r31505
Allow untyped placeholder to take arbitrary type, but default to Void.
Add _undefined<T>() function, which is like fatalError() but has
arbitrary return type. In playground mode, merely warn about outstanding
placeholders instead of erroring out, and transform placeholders into
calls to _undefined(). This way, code with outstanding placeholders will
only crash when it attempts to evaluate such placeholders.
<rdar://problem/21167372> transform EditorPlaceholderExpr into fatalError()
Swift SVN r31481
This allows tools, like code completion or jumping to definition, to be able to resolve
function names even though the argument is wrong.
Swift SVN r31387
When users complete the right-hand side of an assignment expression, we only
show the results whose types are convertible to those of the left-hand side.
Swift SVN r31357
Before this commit, for unresolved members, code completion suggests all visible enum elements
and option set types. To refine the results, this commit uses constraint solver to infer
the type of unresolved members by analyzing parental expressions. If the solver has solutions,
we complete the unresolved member, otherwise abort.
rdar://16659653
Swift SVN r31195
the regressions that r31105 introduced in the validation tests, as well as fixing a number
of other validation tests as well.
Introduce a new UnresolvedType to the type system, and have CSDiags start to use it
as a way to get more type information out of incorrect subexpressions. UnresolvedType
generally just propagates around the type system like a type variable:
- it magically conforms to all protocols
- it CSGens as an unconstrained type variable.
- it ASTPrints as _, just like a type variable.
The major difference is that UnresolvedType can be used outside the context of a
ConstraintSystem, which is useful for CSGen since it sets up several of them to
diagnose subexpressions w.r.t. their types.
For now, our use of this is extremely limited: when a closureexpr has no contextual
type available and its parameters are invalid, we wipe them out with UnresolvedType
(instead of the previous nulltype dance) to get ambiguities later on.
We also introduce a new FreeTypeVariableBinding::UnresolvedType approach for
constraint solving (and use this only in one place in CSDiags so far, to resolve
the callee of a CallExpr) which solves a system and rewrites any leftover type
variables as UnresolvedTypes. This allows us to get more precise information out,
for example, diagnosing:
func r22162441(lines: [String]) {
lines.map { line in line.fooBar() }
}
with: value of type 'String' has no member 'fooBar'
instead of: type of expression is ambiguous without more context
This improves a number of other diagnostics as well, but is just the infrastructural
stepping stone for greater things.
Swift SVN r31130
as a way to get more type information out of incorrect subexpressions. UnresolvedType
generally just propagates around the type system like a type variable:
- it magically conforms to all protocols
- it CSGens as an unconstrained type variable.
- it ASTPrints as _, just like a type variable.
The major difference is that UnresolvedType can be used outside the context of a
ConstraintSystem, which is useful for CSGen since it sets up several of them to
diagnose subexpressions w.r.t. their types.
For now, our use of this is extremely limited: when a closureexpr has no contextual
type available and its parameters are invalid, we wipe them out with UnresolvedType
(instead of the previous nulltype dance) to get ambiguities later on.
We also introduce a new FreeTypeVariableBinding::UnresolvedType approach for
constraint solving (and use this only in one place in CSDiags so far, to resolve
the callee of a CallExpr) which solves a system and rewrites any leftover type
variables as UnresolvedTypes. This allows us to get more precise information out,
for example, diagnosing:
func r22162441(lines: [String]) {
lines.map { line in line.fooBar() }
}
with: value of type 'String' has no member 'fooBar'
instead of: type of expression is ambiguous without more context
This improves a number of other diagnostics as well, but is just the infrastructural
stepping stone for greater things.
Swift SVN r31105
When CSGen was analyzing a DeclRefExpr reference, it was accidentally
applying some magic only to anonymous closure parameters, not named ones,
leading to a silent CSGen failure. Fix this by handling all closure parameters
the same way.
Swift SVN r31098
This bug triggered when three pre-conditions held:
- A protocol requirement method signature involves archetypes built
from associated types
- A protocol extension provides a default implementation of this method
- The method is called from another method in the same extension,
with a parameter of the associated type
In this case, the archetypes in the signature would match exactly
and we would end up picking the extension method over the protocol
method, which would not even be considered. As a result, the
extension method would be dispatch statically instead of using
witness method dispatch, which is wrong.
Hopefully one day we can model default implementations as real
overrides and not overloads.
Note that the test is a SILGen test even though the bug is in Sema,
since its easier to detect the problem at the SIL level.
Fixes <rdar://problem/21995666>.
Swift SVN r30847
to decide whether they're exhaustive.
Unfortunately, we can't actually just type-check the pattern
because it might be dependent on other local type-checking state,
like the types of arguments or variables defined within the closure.
So instead we try to recognize a very specific pattern shape that
should be safe to coerce.
Also, this potentially introduces redundant diagnostics because
of the double-check, but it's tricky to do anything about it.
I think it's better to have these potential redundancies than
to infer a throwing closure type with 'catch let e as NSError',
though.
rdar://21715350
Swift SVN r30701
