If a generic parameter is not referred to from a function signature, it can never be inferred and thus such a function can never be invoked.
We now produce the following error:
generic parameter 'T' is not used in function signature
func f8<T> (x: Int) {}
This commit takes Jordan't comments on r28181 into account:
- it produces a shorter error message
- it does not change the compiler_crashers_fixed test and add a new expected error instead
Swift SVN r28194
If a generic parameter is not referred to from a function signature, it can never be inferred and thus such a function can never be invoked.
We now produce the following error:
There is no way to infer the generic parameter 'T' if it is not used in function signature
func f8<T> (x: Int) {}
^
Swift SVN r28181
Having semantic checking in type validation introduces the potential for more recursion, triggering crashes. By moving this semantic restriction out to a later stage, we make it more robust. Fixes 6 compiler crashers, although it regressed one compiler crasher that hits a different known issue (assertions in addGenericParameters when we have multiple parameters at the same depth).
Swift SVN r26226
This was because the ambiguity between c-style and foreach loops wasn't being
properly handled. Use the canParsePattern() logic to handle this in full
generality.
Since that logic was unused, dust it off and clean it up a bit. Similarly,
remove some old vestigates of default argument parsing in tuples and
old-syntax array handling.
Swift SVN r26164
type checking any of the members of the type being analyzed, which leads to the
really exciting task of generating (e.g.) a memberwise initializer when you don't
know what the types of the members are.
Instead, synthesize these after the members are checked, which makes the code flow
much more like the other code synthesis stuff we do, and paves the way for future
improvements. NFC except one diagnostic in an error case (due to an order-of-checking
change).
This resolves <rdar://problem/16921173> implicit constructor synthesization works without validating the members of the type
Swift SVN r25545
These haven't ever been safe in Swift's development because they require
generating thunks, and we currently don't do that. However, we were letting
existential conversions slip through the cracks because we consider them
subtypes, so that /metatype/ conversions work correctly. To be concrete:
"let _: Any.Type = Int.self" is okay.
"let _: (Int) -> Void = { (_: Any) -> Void in return }" is not.
We should implement this some day; that's rdar://problem/19517003.
This produces some lousy error messages, which I intend to fix soon.
Part of rdar://problem/19600325
Swift SVN r24915
Before:
error: use of module 'Foo' as a type
After:
error: use of undeclared type 'Foo'
note: cannot use module 'Foo' as a type
Improves on rdar://problem/17763309 a little.
Swift SVN r24564
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
everything the type attribute does (notably, doesn't work on parameters),
but this includes the infrastructure to apply it in all the sordid places
that need to be touched for type-adjusting declattributes on variables.
Swift SVN r24044
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
Use the same token-splitting technique we use to interpret '>>>' as a series of closing angle brackets to also extract '?' and '!' IUO sigils. Tweak it so that we properly reset the lexer state instead of just peeking the next token, because otherwise, when we chop a token like '>?>>', we'll see only the '?' (because '?' by itself is a question_postfix) and drop the '>>' on the floor. Remove the lexer hacks that pattern-matched specific >?>? sequences.
Swift SVN r22669
This prevents us from going through a redundant code path for handling '?' and '!' in types which didn't account for a following '->', causing us to fail to parse [T]? -> U. rdar://problem/18604887
Swift SVN r22650
To limit user confusion when using conditional expressions of type Bool?, we've decided to remove the BooleanType (aka "LogicValue") conformance from optional types. (If users would like to use an expression of type Bool? as a conditional, they'll need to check against nil.)
Note: This change effectively regresses the "case is" pattern over types, since it currently demands a BooleanType conformance. I've filed rdar://problem/17791533 to track reinstating it if necessary.
Swift SVN r20637
Mechanically add "Type" to the end of any protocol names that don't end
in "Type," "ible," or "able." Also, drop "Type" from the end of any
associated type names, except for those of the *LiteralConvertible
protocols.
There are obvious improvements to make in some of these names, which can
be handled with separate commits.
Fixes <rdar://problem/17165920> Protocols `Integer` etc should get
uglier names.
Swift SVN r19883
We haven't been advertising this syntax much, and it's closure form
was completely broken anyway, so don't jump through hoops to provide
great Fix-Its here.
Swift SVN r19277
We were ending up with double optionals because we were transforming
both the BindOptionalExpr and the OptionalEvaluationExpr;
BindOptionalExpr is the one where the ? is actually written, so
transform that one and skip the OptionalEvaluationExpr.
Swift SVN r19273
Handle parsing of dictionary type sugar into its own type
representation, including both type and expression contexts.
This is the first part of <rdar://problem/17460972>; we still need a
sugared Type node.
Swift SVN r19239
Better to describe how the protocol can be used than how it can't. Also include a mention of Self type requirements as a source of non-existentiability.
Swift SVN r19207
These types are often useless and confusing to users who expect to be able to use Sequence or Generator as types in their own right like in C# or Java. While we're here, relax the rules for self-conformance to admit methods returning 'Self'. Covariant return types should not actually prevent a protocol type from conforming to itself, and the stdlib makes particular use of protocols with 'init' requirements which implicitly return Self.
Swift SVN r18989
