[ConstraintSystem] Make sure that @autoclosure argument detection works for subscripts/members
Currently logic in `matchCallArguments` could only detect argument
being an @autoclosure parameter for normal calls and operators.
This patch extends it to support subscripts and unresolved member calls.
diff --git a/lib/Sema/CSSimplify.cpp b/lib/Sema/CSSimplify.cpp
index ea8a9f2..37893bb 100644
--- a/lib/Sema/CSSimplify.cpp
+++ b/lib/Sema/CSSimplify.cpp
@@ -848,18 +848,7 @@
auto isAutoClosureArg = [&](Expr *anchor, unsigned argIdx) -> bool {
assert(anchor);
- auto *call = dyn_cast<ApplyExpr>(anchor);
- if (!call)
- return false;
-
- Expr *argExpr = nullptr;
- if (auto *PE = dyn_cast<ParenExpr>(call->getArg())) {
- assert(argsWithLabels.size() == 1);
- argExpr = PE->getSubExpr();
- } else if (auto *TE = dyn_cast<TupleExpr>(call->getArg())) {
- argExpr = TE->getElement(argIdx);
- }
-
+ auto *argExpr = getArgumentExpr(anchor, argIdx);
if (!argExpr)
return false;
diff --git a/lib/Sema/ConstraintSystem.cpp b/lib/Sema/ConstraintSystem.cpp
index 51a674e..7ec35af 100644
--- a/lib/Sema/ConstraintSystem.cpp
+++ b/lib/Sema/ConstraintSystem.cpp
@@ -2356,3 +2356,23 @@
return locator->getAnchor();
}
+
+Expr *constraints::getArgumentExpr(Expr *expr, unsigned index) {
+ Expr *argExpr = nullptr;
+ if (auto *AE = dyn_cast<ApplyExpr>(expr))
+ argExpr = AE->getArg();
+ else if (auto *UME = dyn_cast<UnresolvedMemberExpr>(expr))
+ argExpr = UME->getArgument();
+ else if (auto *SE = dyn_cast<SubscriptExpr>(expr))
+ argExpr = SE->getIndex();
+ else
+ return nullptr;
+
+ if (auto *PE = dyn_cast<ParenExpr>(argExpr)) {
+ assert(index == 0);
+ return PE->getSubExpr();
+ }
+
+ assert(isa<TupleExpr>(argExpr));
+ return cast<TupleExpr>(argExpr)->getElement(index);
+}
diff --git a/lib/Sema/ConstraintSystem.h b/lib/Sema/ConstraintSystem.h
index 93fd294..62066d7 100644
--- a/lib/Sema/ConstraintSystem.h
+++ b/lib/Sema/ConstraintSystem.h
@@ -3458,6 +3458,13 @@
/// null otherwise.
Expr *simplifyLocatorToAnchor(ConstraintSystem &cs, ConstraintLocator *locator);
+/// Retrieve argument at specified index from given expression.
+/// The expression could be "application", "subscript" or "member" call.
+///
+/// \returns argument expression or `nullptr` if given "base" expression
+/// wasn't of one of the kinds listed above.
+Expr *getArgumentExpr(Expr *expr, unsigned index);
+
class DisjunctionChoice {
unsigned Index;
Constraint *Choice;
diff --git a/test/Compatibility/attr_autoclosure.swift b/test/Compatibility/attr_autoclosure.swift
index db652de..b0ec084 100644
--- a/test/Compatibility/attr_autoclosure.swift
+++ b/test/Compatibility/attr_autoclosure.swift
@@ -36,3 +36,12 @@
foo(c)
}
}
+
+func passAutoClosureToSubscript(_ fn: @autoclosure () -> Int) {
+ struct S {
+ subscript(_ fn: @autoclosure () -> Int) -> Int { return fn() }
+ }
+
+ let s = S()
+ let _ = s[fn] // Ok
+}
