[cfe] Report cyclic typedef use in bounds of type parameters
Closes #43975.
Bug: https://github.com/dart-lang/sdk/issues/43975
Change-Id: Ia7e7b6c46d3c0d2eaa2e809008847d3f47897d2e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/182780
Reviewed-by: Johnni Winther <johnniwinther@google.com>
Commit-Queue: Dmitry Stefantsov <dmitryas@google.com>
diff --git a/pkg/front_end/lib/src/fasta/builder/function_type_builder.dart b/pkg/front_end/lib/src/fasta/builder/function_type_builder.dart
index 1f5bbe7..26f56fc 100644
--- a/pkg/front_end/lib/src/fasta/builder/function_type_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/function_type_builder.dart
@@ -107,6 +107,8 @@
typeParameters = <TypeParameter>[];
for (TypeVariableBuilder t in typeVariables) {
typeParameters.add(t.parameter);
+ // Build the bound to detect cycles in typedefs.
+ t.bound?.build(library, origin);
}
}
return new FunctionType(positionalParameters, builtReturnType,
diff --git a/pkg/front_end/lib/src/fasta/builder/type_alias_builder.dart b/pkg/front_end/lib/src/fasta/builder/type_alias_builder.dart
index c4c5502..2f94d08 100644
--- a/pkg/front_end/lib/src/fasta/builder/type_alias_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/type_alias_builder.dart
@@ -426,4 +426,18 @@
}
}
+/// Used to detect cycles in the declaration of a typedef
+///
+/// When a typedef is built, [pendingTypeAliasMarker] is used as a placeholder
+/// value to indicated that the process has started. If somewhere in the
+/// process of building the typedef this value is encountered, it's replaced
+/// with [cyclicTypeAliasMarker] as the result of the build process.
+final InvalidType pendingTypeAliasMarker = new InvalidType();
+
+/// Used to detect cycles in the declaration of a typedef
+///
+/// When a typedef is built, [pendingTypeAliasMarker] is used as a placeholder
+/// value to indicated that the process has started. If somewhere in the
+/// process of building the typedef this value is encountered, it's replaced
+/// with [cyclicTypeAliasMarker] as the result of the build process.
final InvalidType cyclicTypeAliasMarker = new InvalidType();
diff --git a/pkg/front_end/lib/src/fasta/source/source_type_alias_builder.dart b/pkg/front_end/lib/src/fasta/source/source_type_alias_builder.dart
index 5f1a2d2..b84b276 100644
--- a/pkg/front_end/lib/src/fasta/source/source_type_alias_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_type_alias_builder.dart
@@ -128,17 +128,20 @@
DartType buildThisType() {
if (thisType != null) {
- if (identical(thisType, cyclicTypeAliasMarker)) {
+ if (identical(thisType, pendingTypeAliasMarker)) {
+ thisType = cyclicTypeAliasMarker;
library.addProblem(templateCyclicTypedef.withArguments(name),
charOffset, noLength, fileUri);
return const InvalidType();
+ } else if (identical(thisType, cyclicTypeAliasMarker)) {
+ return const InvalidType();
}
return thisType;
}
// It is a compile-time error for an alias (typedef) to refer to itself. We
// detect cycles by detecting recursive calls to this method using an
// instance of InvalidType that isn't identical to `const InvalidType()`.
- thisType = cyclicTypeAliasMarker;
+ thisType = pendingTypeAliasMarker;
TypeBuilder type = this.type;
if (type != null) {
DartType builtType =
@@ -150,7 +153,11 @@
tv.bound?.build(library);
}
}
- return thisType = builtType;
+ if (identical(thisType, cyclicTypeAliasMarker)) {
+ return thisType = const InvalidType();
+ } else {
+ return thisType = builtType;
+ }
} else {
return thisType = const InvalidType();
}
diff --git a/pkg/front_end/testcases/general/issue43975.dart b/pkg/front_end/testcases/general/issue43975.dart
new file mode 100644
index 0000000..929affa
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43975.dart
@@ -0,0 +1,6 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+typedef F = void Function<X extends F>() Function();
+void main() {}
diff --git a/pkg/front_end/testcases/general/issue43975.dart.outline.expect b/pkg/front_end/testcases/general/issue43975.dart.outline.expect
new file mode 100644
index 0000000..a61aa23
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43975.dart.outline.expect
@@ -0,0 +1,13 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue43975.dart:5:9: Error: The typedef 'F' has a reference to itself.
+// typedef F = void Function<X extends F>() Function();
+// ^
+//
+import self as self;
+
+typedef F = invalid-type;
+static method main() → void
+ ;
diff --git a/pkg/front_end/testcases/general/issue43975.dart.strong.expect b/pkg/front_end/testcases/general/issue43975.dart.strong.expect
new file mode 100644
index 0000000..a1da936
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43975.dart.strong.expect
@@ -0,0 +1,12 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue43975.dart:5:9: Error: The typedef 'F' has a reference to itself.
+// typedef F = void Function<X extends F>() Function();
+// ^
+//
+import self as self;
+
+typedef F = invalid-type;
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/issue43975.dart.strong.transformed.expect b/pkg/front_end/testcases/general/issue43975.dart.strong.transformed.expect
new file mode 100644
index 0000000..a1da936
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43975.dart.strong.transformed.expect
@@ -0,0 +1,12 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue43975.dart:5:9: Error: The typedef 'F' has a reference to itself.
+// typedef F = void Function<X extends F>() Function();
+// ^
+//
+import self as self;
+
+typedef F = invalid-type;
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/issue43975.dart.textual_outline.expect b/pkg/front_end/testcases/general/issue43975.dart.textual_outline.expect
new file mode 100644
index 0000000..ccb87d9
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43975.dart.textual_outline.expect
@@ -0,0 +1,2 @@
+typedef F = void Function<X extends F>() Function();
+void main() {}
diff --git a/pkg/front_end/testcases/general/issue43975.dart.textual_outline_modelled.expect b/pkg/front_end/testcases/general/issue43975.dart.textual_outline_modelled.expect
new file mode 100644
index 0000000..ccb87d9
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43975.dart.textual_outline_modelled.expect
@@ -0,0 +1,2 @@
+typedef F = void Function<X extends F>() Function();
+void main() {}
diff --git a/pkg/front_end/testcases/general/three_typedefs_loop.dart.outline.expect b/pkg/front_end/testcases/general/three_typedefs_loop.dart.outline.expect
index 12b78a9..f030616 100644
--- a/pkg/front_end/testcases/general/three_typedefs_loop.dart.outline.expect
+++ b/pkg/front_end/testcases/general/three_typedefs_loop.dart.outline.expect
@@ -13,7 +13,7 @@
import self as self;
import "dart:core" as core;
-typedef Foo<unrelated T extends core::Object* = dynamic> = (((invalid-type) →* void) →* void) →* void;
+typedef Foo<unrelated T extends core::Object* = dynamic> = invalid-type;
typedef Bar<unrelated T extends core::Object* = dynamic> = ((invalid-type) →* void) →* void;
typedef Baz<unrelated T extends core::Object* = dynamic> = (invalid-type) →* void;
static method main() → dynamic
diff --git a/pkg/front_end/testcases/general/three_typedefs_loop.dart.strong.expect b/pkg/front_end/testcases/general/three_typedefs_loop.dart.strong.expect
index 3773b6f..bd2fff9 100644
--- a/pkg/front_end/testcases/general/three_typedefs_loop.dart.strong.expect
+++ b/pkg/front_end/testcases/general/three_typedefs_loop.dart.strong.expect
@@ -13,7 +13,7 @@
import self as self;
import "dart:core" as core;
-typedef Foo<unrelated T extends core::Object* = dynamic> = (((invalid-type) →* void) →* void) →* void;
+typedef Foo<unrelated T extends core::Object* = dynamic> = invalid-type;
typedef Bar<unrelated T extends core::Object* = dynamic> = ((invalid-type) →* void) →* void;
typedef Baz<unrelated T extends core::Object* = dynamic> = (invalid-type) →* void;
static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/three_typedefs_loop.dart.strong.transformed.expect b/pkg/front_end/testcases/general/three_typedefs_loop.dart.strong.transformed.expect
index 3773b6f..bd2fff9 100644
--- a/pkg/front_end/testcases/general/three_typedefs_loop.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/general/three_typedefs_loop.dart.strong.transformed.expect
@@ -13,7 +13,7 @@
import self as self;
import "dart:core" as core;
-typedef Foo<unrelated T extends core::Object* = dynamic> = (((invalid-type) →* void) →* void) →* void;
+typedef Foo<unrelated T extends core::Object* = dynamic> = invalid-type;
typedef Bar<unrelated T extends core::Object* = dynamic> = ((invalid-type) →* void) →* void;
typedef Baz<unrelated T extends core::Object* = dynamic> = (invalid-type) →* void;
static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general_nnbd_opt_out/three_typedefs_loop.dart.weak.expect b/pkg/front_end/testcases/general_nnbd_opt_out/three_typedefs_loop.dart.weak.expect
index de06f6f..d648775a 100644
--- a/pkg/front_end/testcases/general_nnbd_opt_out/three_typedefs_loop.dart.weak.expect
+++ b/pkg/front_end/testcases/general_nnbd_opt_out/three_typedefs_loop.dart.weak.expect
@@ -13,7 +13,7 @@
import self as self;
import "dart:core" as core;
-typedef Foo<unrelated T extends core::Object* = dynamic> = (((invalid-type) →* void) →* void) →* void;
+typedef Foo<unrelated T extends core::Object* = dynamic> = invalid-type;
typedef Bar<unrelated T extends core::Object* = dynamic> = ((invalid-type) →* void) →* void;
typedef Baz<unrelated T extends core::Object* = dynamic> = (invalid-type) →* void;
static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general_nnbd_opt_out/three_typedefs_loop.dart.weak.transformed.expect b/pkg/front_end/testcases/general_nnbd_opt_out/three_typedefs_loop.dart.weak.transformed.expect
index de06f6f..d648775a 100644
--- a/pkg/front_end/testcases/general_nnbd_opt_out/three_typedefs_loop.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general_nnbd_opt_out/three_typedefs_loop.dart.weak.transformed.expect
@@ -13,7 +13,7 @@
import self as self;
import "dart:core" as core;
-typedef Foo<unrelated T extends core::Object* = dynamic> = (((invalid-type) →* void) →* void) →* void;
+typedef Foo<unrelated T extends core::Object* = dynamic> = invalid-type;
typedef Bar<unrelated T extends core::Object* = dynamic> = ((invalid-type) →* void) →* void;
typedef Baz<unrelated T extends core::Object* = dynamic> = (invalid-type) →* void;
static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/rasta/malformed_function_type.dart.outline.expect b/pkg/front_end/testcases/rasta/malformed_function_type.dart.outline.expect
index 6c35ab9..dc3f69b 100644
--- a/pkg/front_end/testcases/rasta/malformed_function_type.dart.outline.expect
+++ b/pkg/front_end/testcases/rasta/malformed_function_type.dart.outline.expect
@@ -7,8 +7,7 @@
// ^
//
import self as self;
-import "dart:core" as core;
-typedef Handle = (core::String*) →* invalid-type;
+typedef Handle = invalid-type;
static method main() → dynamic
;
diff --git a/pkg/front_end/testcases/rasta/malformed_function_type.dart.strong.expect b/pkg/front_end/testcases/rasta/malformed_function_type.dart.strong.expect
index 1cb9f39..3444c42 100644
--- a/pkg/front_end/testcases/rasta/malformed_function_type.dart.strong.expect
+++ b/pkg/front_end/testcases/rasta/malformed_function_type.dart.strong.expect
@@ -7,9 +7,8 @@
// ^
//
import self as self;
-import "dart:core" as core;
-typedef Handle = (core::String*) →* invalid-type;
+typedef Handle = invalid-type;
static method main() → dynamic {
- (core::String*) →* invalid-type h;
+ invalid-type h;
}
diff --git a/pkg/front_end/testcases/rasta/malformed_function_type.dart.strong.transformed.expect b/pkg/front_end/testcases/rasta/malformed_function_type.dart.strong.transformed.expect
index 1cb9f39..3444c42 100644
--- a/pkg/front_end/testcases/rasta/malformed_function_type.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/rasta/malformed_function_type.dart.strong.transformed.expect
@@ -7,9 +7,8 @@
// ^
//
import self as self;
-import "dart:core" as core;
-typedef Handle = (core::String*) →* invalid-type;
+typedef Handle = invalid-type;
static method main() → dynamic {
- (core::String*) →* invalid-type h;
+ invalid-type h;
}
