Parser now accepts multiple patterns in switch cases that contain variables.
Every pattern must contain the same variable names, but can be in arbitrary
positions. New error for variable that doesn't exist in all patterns.
Sema now checks cases with multiple patterns that each occurence of a variable
name is bound to the same type. New error for unexpected types.
SILGen now shares basic blocks for switch cases that contain multiple
patterns. That BB takes incoming arguments from each applicable pattern match
emission with the specific var decls for the pattern that matched.
Added tests for all three of these, and some simple IDE completion
sanity tests.
This tweet: https://twitter.com/radexp/status/694561060230184960 pointed out
the sad truth that most people don't know that stmt-condition can contain
(including a fixit) when they try to use && instead of commas between clauses.
Before:
t.swift:4:16: error: #available may only be used as condition of an 'if', 'guard' or 'while' statement
if x == y && #available(iOS 9, *) { }
^
t.swift:5:27: error: expected '{' after 'if' condition
if #available(iOS 9, *) && x == y {}
^
t.swift:5:37: error: braced block of statements is an unused closure
if #available(iOS 9, *) && x == y {}
^
t.swift:5:37: error: expression resolves to an unused function
if #available(iOS 9, *) && x == y {}
^~
After:
t.swift:4:13: error: expected ',' joining parts of a multi-clause condition
if x == y && #available(iOS 9, *) { }
^~
,
t.swift:5:27: error: expected ',' joining parts of a multi-clause condition
if #available(iOS 9, *) && x == y {}
^~
,
People will keep typing try/catch either due to muscle memory from other languages or
when they are first learning swift. We now produce a nice error message + fixit of:
t.swift:14:3: error: the 'do' keyword is used to specify a 'catch' region
try {
^~~
do
instead of spewing out:
t.swift:15:4: error: consecutive statements on a line must be separated by ';'
} catch { }
^
;
t.swift:15:5: error: expected expression
} catch { }
^
t.swift:15:11: error: braced block of statements is an unused closure
} catch { }
^
t.swift:14:7: error: expression resolves to an unused function
try {
~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
t.swift:15:11: error: expression resolves to an unused function
} catch { }
^~~
t.swift:14:3: warning: no calls to throwing functions occur within 'try' expression
try {
^
Also cleaned up unnecessary body.isNonNull() check here. The code just
above already constructs a synthetic empty brace stmt for the body if
it didn’t have a real one.
Generally speaking, it's necessary to typecheck all parts of a
statement regardless of whether earlier parts failed to typecheck. For
example, even if the condition of an if-statement fails to typecheck, we
should still check its branches. This way all expressions in the AST are
processed (i.e. SequenceExprs translated to trees) and we get more
diagnostics.
The big thing left to fix is for-each statement checking. If there are
any type errors in the pattern or sequence of a for-each statement, the
body doesn't get type-checked.
<rdar://problem/23684220>
Warns of deprecation, checks all the appropriate bits to see if we can
do an automatic fix, and generates fix-its if that is valid.
Also adds a note if the loop looks like it ought to be a simple
for-each, but really isn’t because the loop var is modified inside the
loop.
An invalid `case` construct would incorrectly return a successful status, causing `parseDecl` to crash later when it assumed there were valid decls in the `Entries` vector.
This time, the issue is that TypeNullifier skips bodies of
multi-statement closures. However, ExprRewriter will type
happily pass them on to typeCheckClosureBody(). This could
trigger assertions. Fix this by skipping type checking of
multi-statement closures when diagnosing.
There seems to be a minor QoI regression in some test cases
that already looked pretty dodgy and/or had FIXMEs. However
I think its worth fixing a crash.
Make the following illegal:
switch thing {
case .A(var x):
modify(x0
}
And provide a replacement 'var' -> 'let' fix-it.
rdar://problem/23172698
Swift SVN r32883
fixit hint in CSDiags instead of being a FixKind. This resolves a number of issues with
it, particularly that it didn't actually check to see if the function in question takes
a () argument or not.
This fixes:
<rdar://problem/21692808> QoI: Incorrect 'add ()' fixit with trailing closure
among other issues.
Swift SVN r31728
with no returns *must* be (), add a defaulting constraint
so that it will be inferred as () in the absence of
other possibilities.
The chief benefit here is that it allows better QoI when
the user simply hasn't yet written the return statement.
Doing this does regress a corner case where an attempt
to recover from an uncalled function leads to the
type-checker inferring a result for a closure that
doesn't make any sense at all.
Swift SVN r30476
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
Enhance fixItRemove() to be a bit more careful about what whitespace it leaves around: if the thing it is removing has leading and trailing whitespace already, this nukes an extra space to avoid leaving double spaces or incorrectly indented results.
This includes an extra fix for looking off the start of a buffer, which extractText doesn't and can't handle.
This fixes <rdar://problem/21045509> Fixit deletes 'let' from non-binding 'if case let' statements, but leaves an extra space
Swift SVN r29449
if the thing it is removing has leading and trailing whitespace already, this nukes
an extra space to avoid leaving double spaces or incorrectly indented results. This
fixes <rdar://problem/21045509> Fixit deletes 'let' from non-binding 'if case let' statements, but leaves an extra space
Swift SVN r29419
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
