Merge pull request #85188 from hamishknight/tuple-trouble

[CS] Upgrade a couple of tuple warnings to error for future lang mode

Author: hamishknight

include/swift/AST/DiagnosticsSema.def

@@ -1586,9 +1586,9 @@ WARNING(coercion_may_fail_warning,none,
         "coercion from %0 to %1 may fail; use 'as?' or 'as!' instead",
         (Type, Type))
 
-WARNING(tuple_label_mismatch_warning,none,
-        "tuple conversion from %0 to %1 mismatches labels",
-        (Type, Type))
+ERROR(tuple_label_mismatch,none,
+      "tuple conversion from %0 to %1 mismatches labels",
+      (Type, Type))
 
 ERROR(missing_explicit_conversion,none,
       "%0 is not implicitly convertible to %1; "
@@ -7833,9 +7833,14 @@ ERROR(result_builder_buildpartialblock_accumulated_not_accessible,none,
 // MARK: Tuple Shuffle Diagnostics
 //------------------------------------------------------------------------------
 
- WARNING(warn_reordering_tuple_shuffle_deprecated,Deprecation,
-        "expression shuffles the elements of this tuple; "
-        "this behavior is deprecated", ())
+ERROR(reordering_tuple_shuffle,none,
+      "cannot implicitly reorder tuple elements from '%0' to '%1'",
+      (StringRef, StringRef))
+
+WARNING(warn_reordering_tuple_shuffle_deprecated,Deprecation,
+        "implicit reordering of tuple elements from '%0' to '%1' is deprecated"
+        "; this will be an error in a future Swift language mode",
+        (StringRef, StringRef))
 
 //------------------------------------------------------------------------------
 // MARK: Implicit conversion diagnostics

include/swift/Sema/CSFix.h

@@ -3458,7 +3458,8 @@ class AllowInvalidStaticMemberRefOnProtocolMetatype final
   }
 };
 
-/// Emit a warning for mismatched tuple labels.
+/// Emit a warning for mismatched tuple labels, which is upgraded to an error
+/// for a future language mode.
 class AllowTupleLabelMismatch final : public ContextualMismatch {
   AllowTupleLabelMismatch(ConstraintSystem &cs, Type fromType, Type toType,
                           ConstraintLocator *locator)

lib/Sema/CSApply.cpp

@@ -5822,22 +5822,23 @@ Expr *ExprRewriter::coerceTupleToTuple(Expr *expr,
 
   // Convert each OpaqueValueExpr to the correct type.
   SmallVector<Expr *, 4> converted;
+  SmallVector<Identifier, 4> origLabels;
   SmallVector<Identifier, 4> labels;
   SmallVector<TupleTypeElt, 4> convertedElts;
 
   bool anythingShuffled = false;
   for (unsigned i = 0, e = sources.size(); i != e; ++i) {
     unsigned source = sources[i];
     auto *fromElt = destructured[source];
+    auto fromLabel = fromTuple->getElement(i).getName();
 
     // Actually convert the source element.
     auto toEltType = toTuple->getElementType(i);
     auto toLabel = toTuple->getElement(i).getName();
 
     // If we're shuffling positions and labels, we have to warn about this
     // conversion.
-    if (i != sources[i] &&
-        fromTuple->getElement(i).getName() != toLabel)
+    if (i != sources[i] && fromLabel != toLabel)
       anythingShuffled = true;
 
     auto *toElt
@@ -5849,15 +5850,36 @@ Expr *ExprRewriter::coerceTupleToTuple(Expr *expr,
 
     converted.push_back(toElt);
     labels.push_back(toLabel);
+    origLabels.push_back(fromLabel);
     convertedElts.emplace_back(toEltType, toLabel);
   }
 
   // Shuffling tuple elements is an anti-pattern worthy of a diagnostic.  We
   // will form the shuffle for now, but a future compiler should decline to
   // do so and begin the process of removing them altogether.
   if (anythingShuffled) {
-    ctx.Diags.diagnose(
-        expr->getLoc(), diag::warn_reordering_tuple_shuffle_deprecated);
+    auto concatLabels = [](SmallVectorImpl<Identifier> &labels,
+                           SmallVectorImpl<char> &out) {
+      llvm::raw_svector_ostream OS(out);
+      for (auto label : labels) {
+        DeclName(label).print(OS, /*skipEmpty*/ false, /*escapeIfNeeded*/ true);
+        OS << ':';
+      }
+    };
+    SmallString<16> fromLabelStr;
+    concatLabels(origLabels, fromLabelStr);
+    SmallString<16> toLabelStr;
+    concatLabels(labels, toLabelStr);
+
+    using namespace version;
+    if (ctx.isSwiftVersionAtLeast(Version::getFutureMajorLanguageVersion())) {
+      ctx.Diags.diagnose(expr->getLoc(), diag::reordering_tuple_shuffle,
+                         fromLabelStr, toLabelStr);
+    } else {
+      ctx.Diags.diagnose(expr->getLoc(),
+                         diag::warn_reordering_tuple_shuffle_deprecated,
+                         fromLabelStr, toLabelStr);
+    }
   }
 
   // Create the result tuple, written in terms of the destructured

lib/Sema/CSDiagnostics.cpp

@@ -9419,8 +9419,9 @@ bool InvalidWeakAttributeUse::diagnoseAsError() {
 }
 
 bool TupleLabelMismatchWarning::diagnoseAsError() {
-  emitDiagnostic(diag::tuple_label_mismatch_warning, getFromType(), getToType())
-      .highlight(getSourceRange());
+  emitDiagnostic(diag::tuple_label_mismatch, getFromType(), getToType())
+      .highlight(getSourceRange())
+      .warnUntilFutureSwiftVersion();
   return true;
 }
 

lib/Sema/CSDiagnostics.h

@@ -3009,7 +3009,8 @@ class InvalidWeakAttributeUse final : public FailureDiagnostic {
   bool diagnoseAsError() override;
 };
 
-/// Emit a warning for mismatched tuple labels.
+/// Emit a warning for mismatched tuple labels, which is upgraded to an error
+/// for a future language mode.
 class TupleLabelMismatchWarning final : public ContextualFailure {
 public:
   TupleLabelMismatchWarning(const Solution &solution, Type fromType,

test/Constraints/tuple.swift

@@ -342,27 +342,6 @@ optionalTuple = (bignum, 1) // expected-error {{cannot assign value of type '(In
 optionalTuple = optionalTuple2 // expected-error {{cannot assign value of type '(Int64, Int)?' to type '(Int, Int)?'}}
 // expected-note@-1 {{arguments to generic parameter 'Wrapped' ('(Int64, Int)' and '(Int, Int)') are expected to be equal}}
 
-func testTupleLabelMismatchFuncConversion(fn1: @escaping ((x: Int, y: Int)) -> Void,
-                                          fn2: @escaping () -> (x: Int, Int)) {
-  // Warn on mismatches
-  let _: ((a: Int, b: Int)) -> Void = fn1 // expected-warning {{tuple conversion from '(a: Int, b: Int)' to '(x: Int, y: Int)' mismatches labels}}
-  let _: ((x: Int, b: Int)) -> Void = fn1 // expected-warning {{tuple conversion from '(x: Int, b: Int)' to '(x: Int, y: Int)' mismatches labels}}
-
-  let _: () -> (y: Int, Int) = fn2 // expected-warning {{tuple conversion from '(x: Int, Int)' to '(y: Int, Int)' mismatches labels}}
-  let _: () -> (y: Int, k: Int) = fn2 // expected-warning {{tuple conversion from '(x: Int, Int)' to '(y: Int, k: Int)' mismatches labels}}
-
-  // Attempting to shuffle has always been illegal here
-  let _: () -> (y: Int, x: Int) = fn2 // expected-error {{cannot convert value of type '() -> (x: Int, Int)' to specified type '() -> (y: Int, x: Int)'}}
-
-  // Losing labels is okay though.
-  let _: () -> (Int, Int) = fn2
-
-  // Gaining labels also okay.
-  let _: ((x: Int, Int)) -> Void = fn1
-  let _: () -> (x: Int, y: Int) = fn2
-  let _: () -> (Int, y: Int) = fn2
-}
-
 func testTupleLabelMismatchKeyPath() {
   // FIXME: The warning should be upgraded to an error for key paths.
   let _: KeyPath<(x: Int, y: Int), Int> = \(a: Int, b: Int).x

test/Constraints/tuple_shuffle.swift

@@ -1,31 +1,50 @@
-// RUN: %target-typecheck-verify-swift -swift-version 5
-
- func consume<T>(_ x: T) {} // Suppress unused variable warnings
-
- func shuffle_through_initialization() {
-   let a = (x: 1, y: 2)
-   let b: (y: Int, x: Int)
-   b = a // expected-warning {{expression shuffles the elements of this tuple}}
-   consume(b)
- }
-
-  func shuffle_through_destructuring() {
-   let a = (x: 1, y: 2)
-   let (y: b, x: c) = a // expected-warning {{expression shuffles the elements of this tuple}}
-   consume((b, c))
- }
-
-  func shuffle_through_call() {
-   func foo(_ : (x: Int, y: Int)) {}
-   foo((y: 5, x: 10)) // expected-warning {{expression shuffles the elements of this tuple}}
- }
-
-  func shuffle_through_cast() {
-   let x = ((a: Int(), b: Int()) as (b: Int, a: Int)).0 // expected-warning {{expression shuffles the elements of this tuple}}
-
-   // Ah, the famous double-shuffle
-   let (c1, (c2, c3)): (c: Int, (b: Int, a: Int)) = ((a: Int(), b: Int()), c: Int())
-   // expected-warning@-1 {{expression shuffles the elements of this tuple}}
-   // expected-warning@-2 {{expression shuffles the elements of this tuple}}
-   consume((x, c1, c2, c3))
- }
+// RUN: %target-typecheck-verify-swift -swift-version 6 -verify-additional-prefix swift6-
+// RUN: %target-typecheck-verify-swift -swift-version 7 -verify-additional-prefix swift7-
+
+// REQUIRES: swift7
+
+func consume<T>(_ x: T) {} // Suppress unused variable warnings
+
+func shuffle_through_initialization() {
+  let a = (x: 1, y: 2)
+  let b: (y: Int, x: Int)
+  b = a
+  // expected-swift6-warning@-1 {{implicit reordering of tuple elements from 'x:y:' to 'y:x:' is deprecated; this will be an error in a future Swift language mode}}
+  // expected-swift7-error@-2 {{cannot implicitly reorder tuple elements from 'x:y:' to 'y:x:'}}
+  consume(b)
+}
+
+func shuffle_raw_label(_ t: (`a b`: Int, `c d`: Int)) {
+  let _: (`c d`: Int, `a b`: Int) = t
+  // expected-swift6-warning@-1 {{implicit reordering of tuple elements from '`a b`:`c d`:' to '`c d`:`a b`:' is deprecated; this will be an error in a future Swift language mode}}
+  // expected-swift7-error@-2 {{cannot implicitly reorder tuple elements from '`a b`:`c d`:' to '`c d`:`a b`:'}}
+}
+
+func shuffle_through_destructuring() {
+  let a = (x: 1, y: 2)
+  let (y: b, x: c) = a
+  // expected-swift6-warning@-1 {{implicit reordering of tuple elements from 'x:y:' to 'y:x:' is deprecated; this will be an error in a future Swift language mode}}
+  // expected-swift7-error@-2 {{cannot implicitly reorder tuple elements from 'x:y:' to 'y:x:'}}
+  consume((b, c))
+}
+
+func shuffle_through_call() {
+  func foo(_ : (x: Int, y: Int)) {}
+  foo((y: 5, x: 10))
+  // expected-swift6-warning@-1 {{implicit reordering of tuple elements from 'y:x:' to 'x:y:' is deprecated; this will be an error in a future Swift language mode}}
+  // expected-swift7-error@-2 {{cannot implicitly reorder tuple elements from 'y:x:' to 'x:y:'}}
+}
+
+func shuffle_through_cast() {
+  let x = ((a: Int(), b: Int()) as (b: Int, a: Int)).0
+  // expected-swift6-warning@-1 {{implicit reordering of tuple elements from 'a:b:' to 'b:a:' is deprecated; this will be an error in a future Swift language mode}}
+  // expected-swift7-error@-2 {{cannot implicitly reorder tuple elements from 'a:b:' to 'b:a:'}}
+
+  // Ah, the famous double-shuffle
+  let (c1, (c2, c3)): (c: Int, (b: Int, a: Int)) = ((a: Int(), b: Int()), c: Int())
+  // expected-swift6-warning@-1 {{implicit reordering of tuple elements from 'a:b:' to 'b:a:' is deprecated; this will be an error in a future Swift language mode}}
+  // expected-swift6-warning@-2 {{implicit reordering of tuple elements from '_:c:' to 'c:_:' is deprecated; this will be an error in a future Swift language mode}}
+  // expected-swift7-error@-3 {{cannot implicitly reorder tuple elements from 'a:b:' to 'b:a:'}}
+  // expected-swift7-error@-4 {{cannot implicitly reorder tuple elements from '_:c:' to 'c:_:'}}
+  consume((x, c1, c2, c3))
+}

test/Constraints/tuple_subtype_label_mismatch.swift

@@ -0,0 +1,33 @@
+// RUN: %target-typecheck-verify-swift -language-mode 6 -verify-additional-prefix swift6-
+// RUN: %target-typecheck-verify-swift -language-mode 7 -verify-additional-prefix swift7-
+// REQUIRES: swift7
+
+func testTupleLabelMismatchFuncConversion(fn1: @escaping ((x: Int, y: Int)) -> Void,
+                                          fn2: @escaping () -> (x: Int, Int)) {
+  // Warn on mismatches in Swift 6, upgrading to an error for Swift 7
+  let _: ((a: Int, b: Int)) -> Void = fn1
+  // expected-swift6-warning@-1 {{tuple conversion from '(a: Int, b: Int)' to '(x: Int, y: Int)' mismatches labels}}
+  // expected-swift7-error@-2 {{tuple conversion from '(a: Int, b: Int)' to '(x: Int, y: Int)' mismatches labels}}
+  let _: ((x: Int, b: Int)) -> Void = fn1
+  // expected-swift6-warning@-1 {{tuple conversion from '(x: Int, b: Int)' to '(x: Int, y: Int)' mismatches labels}}
+  // expected-swift7-error@-2 {{tuple conversion from '(x: Int, b: Int)' to '(x: Int, y: Int)' mismatches labels}}
+
+  let _: () -> (y: Int, Int) = fn2
+  // expected-swift6-warning@-1 {{tuple conversion from '(x: Int, Int)' to '(y: Int, Int)' mismatches labels}}
+  // expected-swift7-error@-2 {{tuple conversion from '(x: Int, Int)' to '(y: Int, Int)' mismatches labels}}
+  let _: () -> (y: Int, k: Int) = fn2
+  // expected-swift6-warning@-1 {{tuple conversion from '(x: Int, Int)' to '(y: Int, k: Int)' mismatches labels}}
+  // expected-swift7-error@-2 {{tuple conversion from '(x: Int, Int)' to '(y: Int, k: Int)' mismatches labels}}
+
+  // Attempting to shuffle has always been illegal here
+  let _: () -> (y: Int, x: Int) = fn2
+  // expected-error@-1 {{cannot convert value of type '() -> (x: Int, Int)' to specified type '() -> (y: Int, x: Int)'}}
+
+  // Losing labels is okay though.
+  let _: () -> (Int, Int) = fn2
+
+  // Gaining labels also okay.
+  let _: ((x: Int, Int)) -> Void = fn1
+  let _: () -> (x: Int, y: Int) = fn2
+  let _: () -> (Int, y: Int) = fn2
+}

test/Parse/omit_return.swift

@@ -474,7 +474,7 @@ func ff_implicitInjectIntoOptionalExpr(_ int: Int) -> Int? {
 }
 
 func ff_implicitTupleShuffle(_ input: (one: Int, two: Int)) -> (two: Int, one: Int) {
-    input // expected-warning {{expression shuffles the elements of this tuple; this behavior is deprecated}}
+    input // expected-warning {{implicit reordering of tuple elements from 'one:two:' to 'two:one:' is deprecated; this will be an error in a future Swift language mode}}
 }
 
 func ff_implicitCollectionUpcast(_ derived: [Derived]) -> [Base] {

test/Parse/omit_return_ifdecl.swift

@@ -676,7 +676,7 @@ func ff_implicitInjectIntoOptionalExpr(_ int: Int) -> Int? {
 
 func ff_implicitTupleShuffle(_ input: (one: Int, two: Int)) -> (two: Int, one: Int) {
     #if true
-    input // expected-warning {{expression shuffles the elements of this tuple; this behavior is deprecated}}
+    input // expected-warning {{implicit reordering of tuple elements from 'one:two:' to 'two:one:' is deprecated; this will be an error in a future Swift language mode}}
     #endif
 }