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
