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.
This adds special tuned diagnostics to handle the case when someone attempts to index
a string with an integer value, which is pretty common to do for people new to Swift.o
That said, this only handles one special case, if there are other cases that are
common, I'd love to hear about them. Subscripts are already handled with a different
approach, I'm not sure which is better, but I added a testcase for both of them.
This time, the issue is that TypeNullifier skips bodies of
multi-statement closures. However, ExprRewriter will type
happily pass them on to typeCheckClosureBody(). This could
trigger assertions. Fix this by skipping type checking of
multi-statement closures when diagnosing.
There seems to be a minor QoI regression in some test cases
that already looked pretty dodgy and/or had FIXMEs. However
I think its worth fixing a crash.
It is a somewhat common case where folks are accidentally referring to an
instance member with the Type as the base. This forms a curried member,
which then produced head scratching error messages downstream.
Now that the prep work has gone in, the first part of this is now
straight-forward to fix: simply check for this case and diagnose it
with a custom error, which makes it more clear what the mistake was.
The other half of this problem (tracked by 22108559) affects cases where
the method you're calling takes a single argument. This isn't fixed
yet, but I'm adding a testcase for it anyway.
the code to be actually readable since it unnests it greatly), and call it
both before and after argument type validation. This allows us to capture
many more structural errors than before, leading to much better diagnostics
in a lot of cases. This also fixes the specific regressions introduced by
96a1e96.
overloaded argument list mismatches. We printed them in simple cases
due to "Failure" detecting them in trivial situations. Instead of
doing that, let CSDiags do it, which allows us to pick things out of
overload sets and handle the more complex cases well.
This is a progression across the board except for a couple of cases
where we now produce "cannot convert value of type 'whatever' to
expected argument type '(arglist)'", this is a known issue that I'll
fix in a subsequent commit.
These APIs are from the Swift 1.2 => Swift 2.0 transition, and are not
relevant anymore.
Removing them reduces the surface area of the library that needs to be
reviewed.
Previously we erroneously complained:
error: cannot invoke 'contains' with an argument list of type '(String)'
now we correctly complain:
error: unexpected non-void return value in void function
This enhances CSDiags to use "getTypeOfMember" when analyzing method
candidates that are applied to a known base type. Using it allows us to
substitute information about the base, resolving archetypes that exist in
subsequent argument positions. In the testcase, this means that we use
information about Set<String> to know that the argument to "contains" is a
String.
This allows us to generate much better diagnostics in some cases, and works
around some limitations in the existing stuff for handling unresolved
archetypes. One unfortunate change is the notes in Misc/misc_diagnostics.swift.
Because we don't track argument lists very well, we are flattening an argument
list that is actually ((Int,Int)) into (Int, Int) so we get a bogus looking
diagnostic. This was possible before this patch though, it is just one
more case that triggers the issue.
The original issue has long since been fixed, but we were now producing:
error: cannot subscript a value of type 'UnsafePointer<Int8>'
which is pretty obviously wrong. The problem is that when ranking subscript
decl candidates, CSDiags was using TC.isConvertibleTo to evaluate whether the
actual base type is compatible with the base type of a subscript decl. This
was failing when the base was generic, because the logic isn't opening
archetypes. Instead of incorrectly deciding that they are incompatible, just
decide we don't know if an archetype is present. This allows us to generate
good errors in situation like this.
A crash in CSDiag that happened when we were unconditionally looking at the
getter of a subscript. This failed on UnsafeMutablePointer because it only
has addressors, not getter/setters.
and probably others.
When we're type-checking a failed ApplyExpr that has an overload set that
prevents getting a specific type to feed into the initial typechecking of
the argument list, ranking can often narrow down the list of candidates
further, to the point where there is only one candidate left or where all
candidates agree that one argument is wrong.
In this case, re-type-check the subexpr with the expected type. In the case of
rdar://problem/22243469 we now produce:
t.swift:6:11: error: invalid conversion from throwing function of type '() throws -> ()' to non-throwing function type '() -> Void'
process {
^
instead of:
t.swift:6:3: error: cannot invoke 'process' with an argument list of type '(() throws -> ())'
process {
^
t.swift:6:3: note: overloads for 'process' exist with these partially matching parameter lists: (UInt, fn: () -> Void)
process {
^
Which is a heck of a lot less specific. Similarly, in the testcase from rdar://23550816, instead
of producing:
takeTwoFuncsWithDefaults { $0 + 1 }
error: cannot invoke 'takeTwoFuncsWithDefaults' with an argument list of type '((Int -> Int)?)'
note: expected an argument list of type '(f1: (Int -> Int)?, f2: (String -> String)?)'
we now produce:
error: cannot convert value of type '_ -> Int' to expected argument type '(String -> String)?'
which is a lot closer to what we want to complain about.
This case attempts to diagnose assignment into an invalid lvalue which only had
a computable type due to a fixit that the constraint solver was assuming. In this
situation, don't diagnose the invalid lvalue at all, diagnose the required fix.
When passing a contextual type to a call, if we have a scalar element
initializing a varargs parameter list, we need to use the varargs element type
contextually. Fixing this improves some confusing diagnostics.
call expression onto a callee when it was a binary expression. Doing this
requires improving the diagnostics for when the contextual result type is
incompatible with all candidates, but that is general goodness all around.
This fixes:
<rdar://problem/22333090> QoI: Propagate contextual information in a call to operands
and improves a number of diagnostics where the problem is that an operator
is used in a context that expects a type that it cannot produce.
Swift SVN r31891
- Enhance the branch new argument label overload diagnostic to just
print the argument labels that are the problem, instead of printing
the types inferred at the argument context. This can lead to confusion
particularly when an argument label is missing. For example before:
error: argument labels '(Int)' do not match any available overloads
note: overloads for 'TestOverloadSets.init' exist with these partially matching parameter lists: (a: Z0), (value: Int), (value: Double)
after:
error: argument labels '(_:)' do not match any available overloads
note: overloads for 'TestOverloadSets.init' exist with these partially matching parameter lists: (a: Z0), (value: Int), (value: Double)
Second, fix <rdar://problem/22451001> QoI: incorrect diagnostic when argument to print has the wrong type
by specifically diagnosing the problem when you pass in an argument to a nullary function. Before:
error: cannot convert value of type 'Int' to expected argument type '()'
after:
error: argument passed to call that takes no arguments
print(r22451001(5))
^
Swift SVN r31795
OverloadedDeclRefExpr or OverloadedMemberRefExpr when there is no
contextual type information available. The problem is that CSRanking
will take a look at the various solutions formed by picking each member
of the set, and will arbitrarily rank them against each other based on
how specific the candidates are. The problem with this is that the
constraints on the candidates are being resolved by UnresolvedType, which
means that we end up accidentally pruning the overload set too early.
This can lead to incorrect diagnostics that *should* have been ambiguity
diagnostics, such as the example in TypeCoercion/overload_noncall.swift.
It also is causing me other grief as I'm trying to make the call analysis
diagnostics more specific and the lack of the proper candidates is
triggering badness.
The actual change to the testsuite here is minor, but not all good. It will
be re-won by later changes.
Swift SVN r31744
fixit hint in CSDiags instead of being a FixKind. This resolves a number of issues with
it, particularly that it didn't actually check to see if the function in question takes
a () argument or not.
This fixes:
<rdar://problem/21692808> QoI: Incorrect 'add ()' fixit with trailing closure
among other issues.
Swift SVN r31728
forced conversion to "_ -> T" if it will refine the type otherwise found by
doing a non-contextual type check. This allows us to diagnose calls to
non-function values with more specificity, e.g. adding another case were we
recommend "do" when using bare braces.
Swift SVN r31726
specifies some # of arguments but the closureexpr itself disagrees. This is
step #1 to resolving
<rdar://problem/22333281> QoI: improve diagnostic when contextual type of closure disagrees with arguments
Swift SVN r31715
Introduce a new "OpenedGeneric" locator for when openGeneric opens a generic
decl into a plethora of constraints, and use this in CSDiags to distinguish
whether a constraint refers to an Expr as a whole or an "aspect" of the constraint.
Use that information in FailureDiagnosis::diagnoseGeneralConversionFailure
to know whether (as a fallback) we can correctly re-typecheck an entire expr
to obtain a missing type. If we are talking about an aspect of the expr, then
this clearly won't work.
The upshot of this is that where we previously compiled the testcase in 22519983
to:
y.swift:31:9: error: type '(inout _) -> Bool' does not conform to protocol 'RawRepresentable'
let a = safeAssign
^
we now produce the somewhat more useful:
y.swift:31:9: error: argument for generic parameter 'T' could not be inferred
let a = safeAssign
^
y.swift:27:6: note: in call to function 'safeAssign'
func safeAssign<T: RawRepresentable>(inout lhs: T) -> Bool {
^
Swift SVN r31620
diagnostics around invalid references to unavailable declarations, resolving
<rdar://problem/22491394> References to unavailable decls sometimes diagnosed as ambiguous
and a complex case exposed working through rdar://21928143.
Swift SVN r31587
We type check expressions using a contextual purpose of CTP_CalleeResult
without a specific contextualType, because we install the contextual type
as a conversion constraint. This formerly failed the assertion expecting
that you have to have a type if you have a purpose, because parenexprs
propagated their contextual info down.
In addition to making the assertion in TypeCheckConstraints.cpp more
lenient, change visitCallExpr to just pass down the purpose directly
instead of installing it in its ExprTypeCheckListener.
Swift SVN r31575
use that contextual type to guide typechecking of the callee. This allows us to
propagate that type through generic constraints effectively, making us produce
much more useful diagnostics within closures taking methods like "map" (for
example).
This fixes:
<rdar://problem/20491794> QoI closures: Error message does not tell me what the problem is
Specifically, running the testcase:
enum Color { case Unknown(description: String) }
let xs: (Int, Color) = [1,2].map({ ($0, .Unknown("")) })
produces: error: cannot convert call result type '[_]' to expected type '(Int, Color)'
Changing that to:
let xs: [(Int, Color)] = [1,2].map({ ($0, .Unknown("")) })
produces: error: missing argument label 'description:' in call
... with a fixit to introduce the label.
This also fixes most of 22333090, but we're only using this machinery for CallExprs
so far, not for operators yet.
Swift SVN r31484