Commit Graph

4105 Commits

Author SHA1 Message Date
Chris Lattner
8853d19c2b Dramatically improve the diagnostics when a store is invalid, by taking
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
2015-05-21 05:53:36 +00:00
Chris Lattner
df19d03eb7 When diagnosing invalid assignment errors, dig into the constraint system to see
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
2015-05-20 22:18:52 +00:00
Jordan Rose
2ad796627a Revert "Prefer compiler-provided conformances to those required by other protocols."
This may not be the right solution. Even if it is, there are SourceKit tests
that need updating.

This reverts commit r28849 / rdar://problem/21007417.

Swift SVN r28852
2015-05-20 21:32:56 +00:00
Jordan Rose
1ad7651e19 Prefer compiler-provided conformances to those required by other protocols.
Previously, we'd warn on this code:

  enum Suit { case Spades, Hearts, Clubs, Diamonds }
  extension Suit : Comparable {}
  func <(...) {...}

because both Comparable and the synthesized conformance to Hashable imply
a conformance to Equatable. However, that's silly: Suit already has a
synthesized conformance to Equatable associated with the main 'enum'
declaration, not the extension. These compiler-provided conformances are
part of the language and something people rely on, so rank them higher than
conformances implied by conforming to a refined protocol.

rdar://problem/21007417

Swift SVN r28849
2015-05-20 20:48:04 +00:00
Argyrios Kyrtzidis
4bcb2d0b97 [Sema] Add a compiler fixit for erroneously returning an unnecessary cast of a raw value of a RawOptionSet.
The primary motivation is to address SDK change of a common API.
The diagnostic checks return statements per advice from JoeP to simplify implementation.

rdar://21034343

Swift SVN r28826
2015-05-20 07:53:35 +00:00
Chris Willmore
278d342c22 Remove "materializable" language from diagnostic for 20807269.
Swift SVN r28798
2015-05-19 23:02:22 +00:00
Chris Willmore
5905d07a08 Don't bind generic type parameters to non-materializable types.
Add a new option, TVO_MustBeMaterializable, to
TypeVariableType::Implementation, and set it for type variables
resulting from opening a generic type. This solution isn't complete (we
don't yet copy the non-materializable bit on unification of type
variables, and it's possible to bind a must-be-materializable type
variable to a type with type variables that later get bound to
non-materializable types) but it addresses all reported crashes for this
issue.

<rdar://problem/20807269> Crash in non-materializable type

Swift SVN r28792
2015-05-19 21:50:26 +00:00
Chris Lattner
4b4f909d1a Several tangled up changes:
- Enable 'catch is NSError' and 'catch let e as NSError {' patterns to
   a) work, and b) be considered to be exhaustive catches.  This enables
   people to catch an error and *use* it as an NSError directly, instead
   of having to do boiler-platey cases.  This is particularly important
   for the migrator.

 - Do not warn about non-noop coersion casts (like "_ as NSError" when
   matching an ErrorType), since they provide useful type adjustment to
   the subpattern.  Still warn on noop ones.

 - Simplify CatchStmt::isSyntacticallyExhaustive to use 
   Pattern::isRefutablePattern.  Add a FIXME, because the parser is guiding
   closure "throws" inference before the pattern is type checked, which means
   that it is incorrect (but only in subtle cases).

 - When diagnosing pointless 'as' patterns like:

  switch 4 {
  case _ as Int: break 

say "'as' test is always true" instead of "'is' test is always true".




Swift SVN r28774
2015-05-19 17:32:32 +00:00
Chris Lattner
678b99f347 Fix <rdar://problem/20985280> QoI: improve diagnostic on improper pattern match on type
Where before we would diagnose something like "catch MyType {" with two errors (one of
which complaining about a ~= the user didn't write) and two notes, we now produce:

 error: 'is' keyword required to pattern match against type name

with a fixit hint to insert the 'is'.



Swift SVN r28761
2015-05-19 06:25:50 +00:00
Devin Coughlin
9f4233bdc1 Move validation of #available() from Sema to Parse
In anticipation of adding short-form @available() annotations, move validation
of #available() platform/version lists out of Sema and into the parser. This
also enables slightly more graceful recovery from errors.

Swift SVN r28637
2015-05-15 20:08:25 +00:00
Chris Lattner
8a7b3f414e Revise the parser and AST representation of #available to be part of StmtCondition
instead of being an expression.

To the user, this has a couple of behavior changes, stemming from its non-expression-likeness.
 - #available cannot be parenthesized anymore
 - #available is in its own clause, not used in a 'where' clause of if/let.

Also, the implementation in the compiler is simpler and fits the model better.  This
fixes:
<rdar://problem/20904820> Following a "let" condition with #available is incorrectly rejected



Swift SVN r28521
2015-05-13 19:00:40 +00:00
John McCall
7a5ffeddf4 Implement 'rethrows' checking in Sema.
Now with amazing new fixes and tests for methods and generics!

Swift SVN r28499
2015-05-13 00:03:09 +00:00
Ted Kremenek
07251be929 Revert "Implement 'rethrows' checking in Sema."
This was asserting in the performance suite.

Swift SVN r28491
2015-05-12 22:37:20 +00:00
John McCall
3e4bcab7fb Implement 'rethrows' checking in Sema.
Swift SVN r28488
2015-05-12 22:10:41 +00:00
Ted Kremenek
62feb5c949 Change @availability to @available.
This came out of today's language review meeting.
The intent is to match #available with the attribute
that describes availability.

This is a divergence from Objective-C.

Swift SVN r28484
2015-05-12 20:06:13 +00:00
Slava Pestov
8eabf84450 Sema: diagnose capturing type declarations for now
Properly implementing a class whose methods capture variables
defined in the outer scope requires adding the captures as
hidden vars in the class and initializers, and seems
non-trivial.

Just diagnose this case for now instead of crashing.

Fixes <rdar://problem/20853958>.

Swift SVN r28481
2015-05-12 18:19:37 +00:00
Doug Gregor
340e4d8f8a Simplify parsing and representation of extension declarations.
Now that we don't have generic parameter lists at arbitrary positions
within the extended type of an extension declaration, simplify the
representation of the extended type down to a TypeLoc along with a
(compiler-synthesized) generic parameter list.

On the parsing side, just parse a type for the extended type, rather
than having a special grammar. We still reject anything that is not a
nominal type (of course), but it's simpler just to call it a type.

As a drive-by, fix the crasher when extending a type with module
qualification, rdar://problem/20900870.

Swift SVN r28469
2015-05-12 16:26:13 +00:00
Doug Gregor
985896905e Ban generic parameters on extensions.
We no longer allow extensions to provide generic parameters, and the
ability to parse the syntax

  extension Array<String> { ... }

is causing confusion. Fixes rdar://problem/20873336.

Swift SVN r28468
2015-05-12 16:26:04 +00:00
Chris Lattner
ddd6192094 Implement 3 prominent feature requests:
<rdar://problem/15975935> warning that you can use 'let' not 'var'
<rdar://problem/18876585> Compiler should warn me if I set a parameter as 'var' but never modify it
<rdar://problem/17224539> QoI: warn about unused variables

This uses a simple pass in MiscDiagnostics that walks the body of an
AbstractFunctionDecl.  This means that it doesn't warn about unused properties (etc),
but it captures a vast majority of the cases.

It also does not warn about unused parameters (as a policy decision) because it is too noisy,
there are a variety of other refinements that could be done as well, thoughts welcome.



Swift SVN r28412
2015-05-11 06:26:05 +00:00
Joe Groff
91ade9444d Sema: Allow mutual recursion of local functions.
Local functions may reference each other as long as they don't transitively capture any vars or other non-function local decls before their declaration.

Swift SVN r28394
2015-05-10 16:53:39 +00:00
Chris Lattner
37f5452d15 require -> guard.
Swift SVN r28223
2015-05-06 22:53:38 +00:00
Joe Groff
ab09922966 Runtime/IRGen: Replace the _SwiftNativeNS*Base +load hack with a compiler hack.
Rather than swizzle the superclass of these bridging classes at +load time, have the compiler set their ObjC runtime base classes, using a "@_swift_native_objc_runtime_base" attribute that tells the compiler to use a different implicit base class from SwiftObject. This lets the runtime shed its last lingering +loads, and should overall be more robust, since it doesn't rely on static initialization order or deprecated ObjC runtime calls.

Swift SVN r28219
2015-05-06 22:00:59 +00:00
Roman Levenstein
984fcef576 Produce an error for generic parameters of functions if those parameters are not used in function signature.
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
2015-05-06 02:20:39 +00:00
Roman Levenstein
a3a25000ff Revert "Produce an error for generic parameters of functions if those parameters are not used in function signature."
This reverts commit r28181. I'll change it according to Jordan's comments and re-commit.

Swift SVN r28193
2015-05-06 02:20:36 +00:00
Roman Levenstein
ebe3fddbe6 Produce an error for generic parameters of functions if those parameters are not used in function signature.
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
2015-05-05 21:02:11 +00:00
Chris Lattner
90385937f2 remove some dead code, change the text of a theoretically dead diagnostic in case it ever comes up.
Swift SVN r28152
2015-05-05 05:20:40 +00:00
Slava Pestov
43c96de2b0 Sema: slightly better diagnostics for @objc
If we inferred @objc, say so instead of telling the user they
"marked" the declaration @objc.

Swift SVN r28128
2015-05-04 19:26:25 +00:00
Slava Pestov
58f0b46335 Implement @nonobjc attribute
The following declaration kinds can be marked with this attribute:
- method
- property
- property accessor
- subscript
- constructor

Use cases include resolving circularity for bridging methods in an @objc
class, and allowing overloading methods and constructors in an @objc class
by signature by marking some of them @nonobjc.

It is an error to override an @objc method with a @nonobjc method. The
converse, where we override a @nonobjc method with a @objc method, is
explicitly supported.

It is also an error to put a @nonobjc attribute on a method which is
inferred as @objc due to being part of an @objc protocol conformance.

Fixes <rdar://problem/16763754>.

Swift SVN r28126
2015-05-04 19:26:23 +00:00
Slava Pestov
12d835c1d1 Sema: clean up @objc attribute handling a bit
There was a fair amount of code duplication in handling the various
places where @objc could either be explictly specified or be inferred;
centralize these in a new shouldMarkAsObjC() function. NFC

Swift SVN r28125
2015-05-04 19:26:21 +00:00
Doug Gregor
11b820dbcc Ban extension of the 'AnyObject' protocol.
AnyObject won't always be a protocol, and it may be de-protocol'ified
well before we get the ability to extend an arbitrary type (if that
ever happens), so ban this for now.

Swift SVN r28120
2015-05-04 16:37:26 +00:00
Chris Lattner
e31b915f54 fix <rdar://problem/20800015> Fix error message for invalid if-let
Emitting an error message about a pattern the user didn't write isn't awesome,
complain about the type requirements of an if/let binding specifically.


Swift SVN r28119
2015-05-04 16:36:13 +00:00
Chris Lattner
7927a230ae remove compiler support for let/else. This simplifies PBD back to being
an unconditional binding, yay.


Swift SVN r28101
2015-05-03 22:13:02 +00:00
Devin Coughlin
d04cc58c6c Sema: Refine availability context in IfStmt guard conditions following #available()
Loosen restrictions on where #available() can appear in IfStmt guards and refine the
context for guard StmtConditionElements following an availability check.

This enables #available() to be combined with if let optional binding:

if #available(iOS 8.0, *),
   let x = someIOS8API() {
  // Do more iOS 8 stuff
}

and

if let x = someIOS7API() where #available(iOS 8.0, *),
   let y = someIOS8API() {
  // Do more iOS 8 stuff
}

Swift SVN r28096
2015-05-03 20:27:29 +00:00
John McCall
5c171fd448 Parsing, type-checking, SILGen, and IRGen for try!.
Swift SVN r28085
2015-05-02 08:03:15 +00:00
Chris Lattner
0011b3ae21 rename "unless" to "require" and give it an 'else' keyword.
Swift SVN r28059
2015-05-02 00:16:44 +00:00
Doug Gregor
5cfe5b3383 Diagnose attempts to extend a protocol via a typealias.
Fixes rdar://problem/20756244.

Swift SVN r28026
2015-05-01 05:34:29 +00:00
Doug Gregor
de635a8cd9 Implement the 'warn_unused_result' attribute.
@warn_unused_result can be attached to function declarations to
produce a warning if the function is called but its result is not
used. It has two optional parameters that can be placed in
parentheses:

  message="some message": a message to include with the warning.

  mutable_variant="somedecl": the name of the mutable variant of the
  method that should be suggested when the subject method is called on
  a mutable value.

The specific use we're implementing this for now is for the mutating
and in-place operations. For example:

  @warn_unused_result(mutable_variant="sortInPlace") func sort() -> [Generator.Element] { ... }
  mutating func sortInPlace() { ... }

Translate Clang's __attribute__((warn_unused_result)) into
@warn_unused_result.

Implements rdar://problem/18165189.

Swift SVN r28019
2015-05-01 04:10:40 +00:00
Chris Lattner
2ffb5bb23c diagnose always-true conditions.
Swift SVN r28017
2015-05-01 03:55:08 +00:00
Chris Lattner
c6aa041fb9 Add parser/ast/sema/sourcekit/etc support for 'unless' statement.
SILGen support still missing.



Swift SVN r27961
2015-04-30 05:55:11 +00:00
Chris Lattner
31c01eab73 Change the meaning of "if let x = foo()" back to Xcode 6.4 semantics. The compiler
includes a number of QoI things to help people write the correct code.  I will commit
the testcase for it as the next patch.

The bulk of this patch is moving the stdlib, testsuite and validation testsuite to
the new syntax.  I moved a few uses of "as" patterns back to as? expressions in the 
stdlib as well.



Swift SVN r27959
2015-04-30 04:38:13 +00:00
John McCall
fdcecfcfb7 Move error-handling diagnostics to Sema and check try coverage.
Needs better test-case coverage.

Swift SVN r27898
2015-04-29 00:49:40 +00:00
Chris Lattner
23b713abed fix typo in diagnostic.
Swift SVN r27873
2015-04-28 17:04:00 +00:00
Chris Lattner
88e50659f7 fix <rdar://problem/17564699> QoI: Structs should get convenience initializers
The diagnostic we were producing was confusing the user into thinking that
you couldn't have a delegating init on a struct.  Improve the diagnostic and
add a fixit hint.



Swift SVN r27872
2015-04-28 17:01:48 +00:00
Doug Gregor
8322b06ce6 Revert "Suggest '==' when trying to constraint a generic type by a concrete type."
This reverts r27834, which toggled some compiler crashers.

Swift SVN r27847
2015-04-28 00:03:16 +00:00
Doug Gregor
95fe505b89 Suggest '==' when trying to constraint a generic type by a concrete type.
Fixes rdar://problem/20636279.

Swift SVN r27834
2015-04-27 23:15:33 +00:00
Chris Lattner
0b5c1125e4 improve and consistify diagnostics for non-lvalue inout arguments.
Swift SVN r27795
2015-04-27 01:05:29 +00:00
Chris Lattner
227e676b4b clean up diagnoseFailureForAssignExpr, no significant win though.
Swift SVN r27793
2015-04-27 00:45:10 +00:00
Chris Lattner
9f36074698 fix <rdar://problem/19711233> QoI: poor diagnostic for operator-assignment involving immutable operand
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
2015-04-27 00:20:57 +00:00
Chris Lattner
43c7334abc fix two QoI issues:
- <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
2015-04-26 21:51:50 +00:00
Chris Lattner
bebbdfe001 fix <rdar://problem/17691565> attempt to modify a 'let' variable with ++ results in typecheck error not being able to apply ++ to Float
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
2015-04-26 20:42:19 +00:00