independently (not just if one argument is inout). This routes around issues handling tuples,
and brings more consistency to the experience. Factor this logic out and use it for operators
and subscripts as well.
This improves a small collection of diagnostics, including the infamous:
// Infer incompatible type.
- func6(fn: {a,b->Float in 4.0 }) // expected-error {{cannot convert return expression of type 'Double' to expected return type 'Float'}}
+ func6(fn: {a,b->Float in 4.0 }) // expected-error {{cannot invoke 'func6' with an argument list of type '(fn: (_, _) -> Float)'}}
+ // expected-note @-1 {{expected an argument list of type '(fn: (Int, Int) -> Int)'}}
Swift SVN r30570
diagnose problems inside of them instead of punting on them completely.
This leads to substantially better error messages in many cases, fixing:
<rdar://problem/19870975> Incorrect diagnostic for failed member lookups within closures passed as arguments ("(_) -> _")
<rdar://problem/21883806> Bogus "'_' can only appear in a pattern or on the left side of an assignment" is back
<rdar://problem/20712541> QoI: Int/UInt mismatch produces useless error inside a block
and possibly others. We are not yet capitalizing on available type information we do
have about closure exprs, so there are some cases where we produce
"error: type of expression is ambiguous without more context"
when this isn't strictly true, but this is still a huge step forward.
Swift SVN r30547
detailed analysis of callees, which give us overload sets in more cases,
producing notes more consistently, and producing much better diagnostics
for the curried cases in test/Constraints/diagnostics.swift.
This also allows us to eliminate getCalleeName, which simplifies things
in CSDiags.
Swift SVN r30491
rationalizing how it handles members and curried functions, also paving
the way for future improvements. This implements the infrastructure but
keeps the functionality the same (the only functionality change is that
it works a bit better with vardecls of function type).
Swift SVN r30464
fixing:
<rdar://problem/20789423> Unclear diagnostic for multi-statement closure with no return type
<rdar://problem/21829141> BOGUS: unexpected trailing closure
<rdar://problem/21784170> Incongruous `unexpected trailing closure` error in `init` function which is cast and called without trailing closure.
Swift SVN r30443
we can start taking advantage of ambiguously typed subexpressions in CSDiags. We
start by validating the callee function of ApplyExprs, which substantially improves
our abilities to generate precise diagnostics about malformed calls.
This is the minimal introduction of this concept to CSDiags, a lot of refactoring
is yet to come, however, this is enough to resolve:
<rdar://problem/21080030> Bad diagnostic for invalid method call in boolean expression
<rdar://problem/21784170> Incongruous `unexpected trailing closure` error in `init` function which is cast and called without trailing closure.
one of the testcases from:
<rdar://problem/20789423> Unclear diagnostic for multi-statement closure with no return type
and a bunch of other places where we got weird "unexpected trailing closure"
diagnostics that made no sense. As usual, it is two steps forward and one step back,
as this exposed some other weird latent issues like:
<rdar://problem/21900971> QoI: Bogus conversion error in generics case
Swift SVN r30429
return statements, or a return statement with no operand.
Also, fix a special-case diagnostic about converting a return
expression to (1) only apply to converting the actual return
expression, not an arbitrary sub-expression, and (2) use the
actual operand and return types, not the drilled-down types
that caused the failure.
Swift SVN r30420
DiscardAssignmentExpr's, because they require context to typecheck anyway
and doing so triggers bogus errors about _ needing to be on the LHS of an
assignment. There is a correct way to fix this, but layers of issues need
to be peeled off before that can happen.
This fixes <rdar://problem/21883806> Bogus "'_' can only appear in a pattern or on the left side of an assignment" is back
but the new diagnostic that is revealed now that this bogus one is removed is
also really bad.
Swift SVN r30369
value, and use that to rank a problem as very specific. This required indicating a difference
between singular argument mismatch vs self mismatch and single-argument mismatch (which is very
specific) as being different from the argument list in general mismatching (which matters to
differentiate argument lists that contain a single argument).
These extra mechanics combine to fix <rdar://problem/21362748> [WWDC Lab] QoI: cannot subscript a value of type '[Int]?' with an index of type 'Int'
Swift SVN r30305
- Remove all uses of CleanupIllFormedExpressionRAII from this file, which are now
unnecessary since this is handled at a higher level.
- Stop splatting ErrorType in the diagnostics stuff. This was formerly needed to
indicate that a diagnostic is emitted, but is now handled other ways. Removing
this enables the type checker to produce other follow on warnings in some cases
(e.g. var should be marked let).
- Remove an arbitrary limitation on unop and binops that didn't print an overload
candidate set with one entry, leading to better consistency in diagnostics, now
that all the pieces are in place to make this not be super annoying.
Swift SVN r30084
facilities used by operators etc. This required a bunch of changes to make
the diagnostics changes strictly an improvement:
- Teach the new path about calls to TypeExprs.
- Teach evaluateCloseness some simple things about varargs.
- Make the generic diagnosis logic produce a better error when there is
exactly one match.
Overall, the resultant diagnostics are a step forward: we now produce candidate
set notes more uniformly, and the messages about some existing ones are
more specific. This is just another stepping stone towards progress though.
Swift SVN r30057
Now for:
let req = NSURLRequest(URL: NSURL(string: "<some url>")!)?
instead of producing:
test.swift:2:58: error: could not find an overload for 'init' that accepts the supplied
we produce the correct diagnostic, with a fixit:
error: cannot use optional chaining on non-optional value of type 'NSURLRequest'
let req = NSURLRequest(URL: NSURL(string: "<some url>")!)?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
This also consolidates some existing diagnostics to improve their wording.
Swift SVN r30049
... by reimplementing the DiscardAssignmentExpr checker in MiscDiagnostics
instead of being in CSApply (which gets run on partial expression ASTs).
Also, when type checking and salvaging an expression fails, do not generate
structural diagnostics in addition to the type checker diagnostics, they are
just noise.
Swift SVN r29937
when we're diagnosing a value member constraint but have resolved the base, then the
member must not exist. Diagnose this with a specific message.
Swift SVN r29908
We used to produce:
test.swift:6:20: error: cannot subscript a value of type '[Int]?' with an index of type 'Int'
return foo.array[0]
^
with the recent subscript improvements we now produce:
error: result type 'Element' does not match expected type
which still isn't a great diagnosis, but at least is the correct problem.
Swift SVN r29867
expressions. Broadening from callexpr to apply expr (picking up operators) improves
several diagnostics in the testsuite, and is important to avoid regressions from an
upcoming patch.
Swift SVN r29821
- Enhance subscript diagnostics to chase into the constraint system to find
overload candidates that failed to match so we can rank and diagnose
subscript ambiguities using the same mechanics we have for operators.
- Implement a copy of suggestPotentialOverloads based on the new mechanics
for overload set resolution. This allows us to diagnose these in a more
detailed way, but for now we're keeping it as similar to the old system as
possible. The old version to be removed once the last client moves off it.
- Add a bunch of testcases to decl/subscript/subscripting.swift where we are
doing unfortunate things still.
Swift SVN r29810
ApplyExpr involved in the overload failure, wire it up to some of the
mechanics we have for more specific situations, including diagnosing
the last (known to me) mutation issues that weren't being specifically
diagnosed, as well as printing the candidate set in these cases.
Swift SVN r29797
This teaches overload constraint diagnosis to look at the resolved anchor
expression that fails (instead of assuming that it is the expr itself) and
walks up the AST to find the applyexpr in question. This allows us to give
much more specific diagnostics for overload resolution failures, and to give
much more specific location information.
Where before my recent patches we used to produce:
t.swift:2:3: error: cannot invoke 'assert' with an argument list of type '(Bool, String)'
assert(a != nil, "ASSERT COMPILATION ERROR")
^
t.swift:2:9: note: expected an argument list of type '(@autoclosure () -> Bool, @autoclosure () -> String, file: StaticString, line: UWord)'
assert(a != nil, "ASSERT COMPILATION ERROR")
^
with this and the other recent patches, we now produce:
t.swift:2:12: error: cannot invoke '!=' with an argument list of type '(Int, nil)'
assert(a != nil, "ASSERT COMPILATION ERROR")
~~^~~~~~
Swift SVN r29792
its diagnostics in post-order. Notably, this picks up support for if-expr, which
gives up much better diagnostics in ternary operators. For example, rdar://17224804
used to produce:
error: could not find an overload for '<=' that accepts the supplied arguments
var monthString = (monthNumber <= 9) ? ("0" + monthNumber) : String(monthNumber)
~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
now we produce:
error: binary operator '+' cannot be applied to operands of type 'String' and 'Int'
var monthString = (monthNumber <= 9) ? ("0" + monthNumber) : String(monthNumber)
~~~ ^ ~~~~~~~~~~~
note: overloads for '+' exist with these partially matching parameter lists: (Int, Int), (String, String), (UnsafeMutablePointer<Memory>, Int), (UnsafePointer<Memory>, Int)
var monthString = (monthNumber <= 9) ? ("0" + monthNumber) : String(monthNumber)
^
which is the correct diagnostic. While I'm at it, improve the location info for this
binary operator diagnostic to point to the right spot (the operator) and highlight
the LHS/RHS of the operator.
Swift SVN r29774
win from this other than simplification. Some minor wins are that we handle varargs
better and don't get extraneous ()'s in types in some cases.
Swift SVN r29729
by propagating the 'is return expr' bit more carefully in sequence folding, and by
adding another path for handling the return diagnostics better.
This probably improves a number of cases where we complain about "this argument list
is invalid" when the call is in the context of a return.
Swift SVN r29565
getTypeOfIndependentSubExpression() might replace some values in the
given expression with OpaqueValueExprs, but if the type checker
decided to insert the corresponding OpenExistentialExpr at the top
level, the AST would now be in an inconsistent state, since
getTypeOfIndependentSubExpression() does not return a new expression
to the caller.
Ideally we would separate out type checking from expression rewriting
so that the latter is only performed when we know the expression
type checks, but that is a bigger project. For now, erase open
existentials after re-typechecking a sub-expression.
Fixes <rdar://problem/20598568>.
Swift SVN r29400
result in slightly more descriptive diagnostics in some cases. (Specifically,
for diagnostics involving binary operators.)
(rdar://problem/21080030)
Swift SVN r29020
The rule changes are as follows:
* All functions (introduced with the 'func' keyword) have argument
labels for arguments beyond the first, by default. Methods are no
longer special in this regard.
* The presence of a default argument no longer implies an argument
label.
The actual changes to the parser and printer are fairly simple; the
rest of the noise is updating the standard library, overlays, tests,
etc.
With the standard library, this change is intended to be API neutral:
I've added/removed #'s and _'s as appropriate to keep the user
interface the same. If we want to separately consider using argument
labels for more free functions now that the defaults in the language
have shifted, we can tackle that separately.
Fixes rdar://problem/17218256.
Swift SVN r27704
Most tests were using %swift or similar substitutions, which did not
include the target triple and SDK. The driver was defaulting to the
host OS. Thus, we could not run the tests when the standard library was
not built for OS X.
Swift SVN r24504
These changes make the following improvements to how we generate diagnostics for expression typecheck failure:
- Customizing a diagnostic for a specific expression kind is as easy as adding a new method to the FailureDiagnosis class,
and does not require intimate knowledge of the constraint solver’s inner workings.
- As part of this patch, I’ve introduced specialized diagnostics for call, binop, unop, subscript, assignment and inout
expressions, but we can go pretty far with this.
- This also opens up the possibility to customize diagnostics not just for the expression kind, but for the specific types
involved as well.
- For the purpose of presenting accurate type info, partially-specialized subexpressions are individually re-typechecked
free of any contextual types. This allows us to:
- Properly surface subexpression errors.
- Almost completely avoid any type variables in our diagnostics. In cases where they could not be eliminated, we now
substitute in "_".
- More accurately indicate the sources of errors.
- We do a much better job of diagnosing disjunction failures. (So no more nonsensical ‘UInt8’ error messages.)
- We now present reasonable error messages for overload resolution failures, informing the user of partially-matching
parameter lists when possible.
At the very least, these changes address the following bugs:
<rdar://problem/15863738> More information needed in type-checking error messages
<rdar://problem/16306600> QoI: passing a 'let' value as an inout results in an unfriendly diagnostic
<rdar://problem/16449805> Wrong error for struct-to-protocol downcast
<rdar://problem/16699932> improve type checker diagnostic when passing Double to function taking a Float
<rdar://problem/16707914> fatal error: Can't unwrap Optional.None…Optional.swift, line 75 running Master-Detail Swift app built from template
<rdar://problem/16785829> Inout parameter fixit
<rdar://problem/16900438> We shouldn't leak the internal type placeholder
<rdar://problem/16909379> confusing type check diagnostics
<rdar://problem/16951521> Extra arguments to functions result in an unhelpful error
<rdar://problem/16971025> Two Terrible Diagnostics
<rdar://problem/17007804> $T2 in compiler error string
<rdar://problem/17027483> Terrible diagnostic
<rdar://problem/17083239> Mysterious error using find() with Foundation types
<rdar://problem/17149771> Diagnostic for closure with no inferred return value leaks type variables
<rdar://problem/17212371> Swift poorly-worded error message when overload resolution fails on return type
<rdar://problem/17236976> QoI: Swift error for incorrectly typed parameter is confusing/misleading
<rdar://problem/17304200> Wrong error for non-self-conforming protocols
<rdar://problem/17321369> better error message for inout protocols
<rdar://problem/17539380> Swift error seems wrong
<rdar://problem/17559593> Bogus locationless "treating a forced downcast to 'NSData' as optional will never produce 'nil'" warning
<rdar://problem/17567973> 32-bit error message is really far from the mark: error: missing argument for parameter 'withFont' in call
<rdar://problem/17671058> Wrong error message: "Missing argument for parameter 'completion' in call"
<rdar://problem/17704609> Float is not convertible to UInt8
<rdar://problem/17705424> Poor error reporting for passing Doubles to NSColor: extra argument 'red' in call
<rdar://problem/17743603> Swift compiler gives misleading error message in "NSLayoutConstraint.constraintsWithVisualFormat("x", options: 123, metrics: nil, views: views)"
<rdar://problem/17784167> application of operator to generic type results in odd diagnostic
<rdar://problem/17801696> Awful diagnostic trying to construct an Int when .Int is around
<rdar://problem/17863882> cannot convert the expression's type '()' to type 'Seq'
<rdar://problem/17865869> "has different argument names" diagnostic when parameter defaulted-ness differs
<rdar://problem/17937593> Unclear error message for empty array literal without type context
<rdar://problem/17943023> QoI: compiler displays wrong error when a float is provided to a Int16 parameter in init method
<rdar://problem/17951148> Improve error messages for expressions inside if statements by pre-evaluating outside the 'if'
<rdar://problem/18057815> Unhelpful Swift error message
<rdar://problem/18077468> Incorrect argument label for insertSubview(...)
<rdar://problem/18079213> 'T1' is not identical to 'T2' lacks directionality
<rdar://problem/18086470> Confusing Swift error message: error: 'T' is not convertible to 'MirrorDisposition'
<rdar://problem/18098995> QoI: Unhelpful compiler error when leaving off an & on an inout parameter
<rdar://problem/18104379> Terrible error message
<rdar://problem/18121897> unexpected low-level error on assignment to immutable value through array writeback
<rdar://problem/18123596> unexpected error on self. capture inside class method
<rdar://problem/18152074> QoI: Improve diagnostic for type mismatch in dictionary subscripting
<rdar://problem/18242160> There could be a better error message when using [] instead of [:]
<rdar://problem/18242812> 6A1021a : Type variable leaked
<rdar://problem/18331819> Unclear error message when trying to set an element of an array constant (Swift)
<rdar://problem/18414834> Bad diagnostics example
<rdar://problem/18422468> Calculation of constant value yields unexplainable error
<rdar://problem/18427217> Misleading error message makes debugging difficult
<rdar://problem/18439742> Misleading error: "cannot invoke" mentions completely unrelated types as arguments
<rdar://problem/18535804> Wrong compiler error from swift compiler
<rdar://problem/18567914> Xcode 6.1. GM, Swift, assignment from Int64 to NSNumber. Warning shown as problem with UInt8
<rdar://problem/18784027> Negating Int? Yields Float
<rdar://problem/17691565> attempt to modify a 'let' variable with ++ results in typecheck error about @lvalue Float
<rdar://problem/17164001> "++" on let value could give a better error message
Swift SVN r23782
modifiers and with the func implementations of the operators. This resolves the rest of:
<rdar://problem/17527000> change operator declarations from "operator prefix" to "prefix operator" & make operator a keyword
Swift SVN r19931
