Revert "Make function parameters and refutable patterns always
immutable"
This reverts commit 8f2fbdc93a.
Once we have finally merged master into the Swift 2.2 branch to be, we
should revert this commit to turn the errors back on for Swift 3.0.
All refutable patterns and function parameters marked with 'var'
is now an error.
- Using explicit 'let' keyword on function parameters causes a warning.
- Don't suggest making function parameters mutable
- Remove uses in the standard library
- Update tests
rdar://problem/23378003
- Produce more specific diagnostics relating to different kinds of invalid
- add a testcase, nfc
- Reimplement FailureDiagnosis::diagnoseGeneralMemberFailure in terms of
Not including r30787 means that we still generate bogus diagnostics like:
[1, 2, 3].doesntExist(0) // expected-error {{type 'Int2048' does not conform to protocol 'IntegerLiteralConvertible'}}
But it is an existing and separable problem from the issues addressed here.
Swift SVN r30819
r30787 causes our tests to time out; the other commits depend on r30787.
Revert "revert part of my previous patch."
Revert "Produce more specific diagnostics relating to different kinds of invalid"
Revert "add a testcase, nfc"
Revert "- Reimplement FailureDiagnosis::diagnoseGeneralMemberFailure in terms of"
Revert "Fix places in the constraint solver where it would give up once a single "
Swift SVN r30805
member references:
- Use of instance members from types
- Use of type members from instances
- Use of mutating getters.
This surely resolves some radars, but I'll have to dig them out later.
Swift SVN r30796
"unavoidable failure" path, along with Failure::DoesNotHaveNonMutatingMember and
just doing some basic disambiguation in CSDiags.
This provides some benefits:
- Allows us to plug in much more specific diagnostics for the existing "only has
mutating members" diagnostic, including producing notes for why the base expr
isn't mutable (see e.g. test/Sema/immutability.swift diffs).
- Corrects issues where we'd drop full decl name info for selector references.
- Wordsmiths diagnostics to not complain about "values of type Foo.Type" instead
complaining about "type Foo"
- Where before we would diagnose all failures with "has no member named", we now
distinguish between when there is no member, and when you can't use it. When you
can't use it, you get a vauge "cannot use it" diagnostic, but...
- This provides an infrastructure for diagnosing other kinds of problems (e.g.
trying to use a private member or a static member from an instance).
- Improves a number of cases where failed type member constraints would produce uglier
diagnostics than a different constraint failure would.
- Resolves a number of rdars, e.g. (and probably others):
<rdar://problem/20294245> QoI: Error message mentions value rather than key for subscript
Swift SVN r30715
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
done, the rest of the infrastructure is all common and can be simplified. This
leaves us with a quite small and maintainable subsystem for diagnosing these
kinds of problems.
include/swift/AST/DiagnosticsSema.def | 28 ++-----
lib/Sema/CSDiag.cpp | 132 ++++++++++------------------------
2 files changed, 48 insertions(+), 112 deletions(-)
Swift SVN r28957
this is neutral w.r.t. diagnostics quality, but deletes a ton
of code:
include/swift/AST/DiagnosticsSema.def | 21 ++---------
lib/Sema/CSDiag.cpp | 64 ++--------------------------------
2 files changed, 9 insertions(+), 76 deletions(-)
Swift SVN r28956
that make vardecls and subscripts immutable. This makes the indirect cases
a lot more specific ("this is a get-only property" instead of "this is
immutable") and allows us to consolidate a bunch of code:
2 files changed, 45 insertions(+), 119 deletions(-)
Swift SVN r28954
which tell you what the problem is, not just that you have one.
- Enhance diagnostics to be more specific about function calls producing
rvalues.
Swift SVN r28939
As far as I know, the compiler now only produces the useless "cannot
assign to the result of this expression" diagnostic in cases that don't
make sense to be an lvalue, like "4 = x".
Swift SVN r28935
a 'var' modifier on the parameter, e.g.:
x.swift:44:5: error: cannot assign to 'let' value 'a'
a = 1
~ ^
x.swift:43:8: note: change 'let' parameter to 'var' to make it mutable
func f(let a : Int) {
^~~
var
x.swift:48:5: error: cannot assign to 'let' value 'b'
b = 2
~ ^
x.swift:47:8: note: mark parameter with 'var' to make it mutable
func g(b : Int) {
^
var
Also fix a bug where we'd incorrectly suggesting adding 'mutating' to a class
method when assigning to self in some cases.
Swift SVN r28926
into account accesibility, assignments to self in a non-mutating
method (consistently), recursive components of an lvalue that makes it
non-settable, etc. Now we tell you what the *problem* was, instead of
just whining.
This fixes:
<rdar://problem/19370429> QoI: fixit to add "mutating" when assigning to a member of self in a struct
<rdar://problem/17632908> QoI: Modifying struct member in non-mutating function produces difficult to understand error message
in their full generality.
Swift SVN r28867
if it has already resolved a member binding of an UnresolvedDotExpr. This allows
us to give tailored diagnostics to indicate whether the destination is not an lvalue
because the property itself was immutable or when the base is immutable.
In addition to improved diagnostics, this allows us to fixit hint "let" to "var" on
property definitions, and we can even go so far as to fixit hint insert 'mutating' on
the enclosing func decl when self is the problem.
This fixes the non-subscript cases of:
<rdar://problem/17632908> QoI: Modifying struct member in non-mutating function produces difficult to understand error message
<rdar://problem/19370429> QoI: fixit to add "mutating" when assigning to a member of self in a struct
<rdar://problem/20234955> QoI: Error message for assigning to 'let' fields should say that the error is due to a 'let' binding
Subscript cases to follow.
Swift SVN r28854
When in an initializer, we allow setting into immutable properties
provided that the type of base in `base.member` matches that of that
initializer's containing type. This was an approximation for allowing
full access into `self` during initialization but this doesn't work when
passing in a different struct of the same type because that struct
should be still be immutable.
Check whether the base of the member access is the implicit self
parameter of the initializer before allowing mutation.
rdar://problem/19814302
Swift SVN r28634
We now produce tailored diagnostics for assignment operators that are passed a non-mutable LHS,
e.g.:
t.swift:14:3: error: cannot pass 'let' value 'x' to mutating binary operator '/='
x /= 19
~ ^
t.swift:13:1: note: change 'let' to 'var' to make it mutable
let x = 42
^~~
var
Swift SVN r27780
- <rdar://problem/16306600> QoI: passing a 'let' value as an inout results in an unfriendly diagnostic
- <rdar://problem/16927246> provide a fixit to change "let" to "var" if needing to mutate a variable
We now refer to an inout argument as such, e.g.:
t.swift:7:9: error: cannot pass 'let' value 'a' as inout argument
swap(&a, &b)
^
we also produce a note with a fixit to rewrite let->var in trivial cases where mutation is
being assed for, e.g.:
t.swift:3:3: note: change 'let' to 'var' to make it mutable
let a = 42
^~~
var
The note is produced by both Sema and DI.
Swift SVN r27774
We now produce diagnostics like:
- cannot pass 'let' value 'a' to mutating unary operator '++'
- cannot pass get-only property 'b' to mutating unary operator '++'
- cannot pass immutable value of type 'Int64' to mutating unary operator '++'
Swift SVN r27772
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
The previous patch to allow static class stored properties
inadvertently allowed 'class final' spellings for static
stored properties in classes. This patch only allows 'static'
spellings to create the global storage.
Swift SVN r24323
rdar://problem/17198298
- Allow 'static' in protocol property and func requirements, but not 'class'.
- Allow 'static' methods in classes - they are 'class final'.
- Only allow 'class' methods in classes (or extensions of classes)
- Remove now unneeded diagnostics related to finding 'static' in previously banned places.
- Update relevant diagnostics to make the new rules clear.
Swift SVN r24260
... now that we have an exquisitely shaved yak.
This provides a simple and uniform model for "let" constants: they are always either
immediately initialized in their declaration, or they are initialized dynamically
exactly once before any use.
This is a simple generalization of our current model for initializers, but enables
the use of let constants in more cases in local context, e.g. patterns like this:
let x : SomeThing
if condition {
x = foo()
} else {
x = bar()
}
use(x)
Previously this would have to be declared a "var" for no good reason: the value is
only ever initialized, never actually mutated.
The implementation of this is reasonably straight-forward now that the infrastructure
is in place: Sema treats 'let' constants as "settable" if they lack an initializer
(either in the declaration or in a non-PBD binding). This exposes them as an lvalue
at the AST level. SILGen then lowers these things to an alloc_stack, and DI enforces
the "initialization only" requirement that it already enforces for uninitialized 'let'
properties in structs/classes.
Swift SVN r23916
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
