[cfe] Use StateError as the pattern matching error in assignments

Part of #49749

Change-Id: I9c4fb121526ca40e5809be8f4a8a5770d551cfb1
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/291063
Commit-Queue: Chloe Stefantsova <[email protected]>
Reviewed-by: Johnni Winther <[email protected]>

Author: chloestefantsova

pkg/front_end/lib/src/fasta/kernel/constant_evaluator.dart

@@ -1666,7 +1666,7 @@ class ConstantsTransformer extends RemovingTransformer {
 
     List<Statement> replacementStatements = [
       ...matchingCache.declarations,
-      // TODO(cstefantsova): Figure out the right exception to throw.
+      // TODO(cstefantsova): Provide a better diagnostic message.
       createIfStatement(
           createNot(readMatchingExpression),
           createExpressionStatement(createThrow(createConstructorInvocation(
@@ -1726,12 +1726,15 @@ class ConstantsTransformer extends RemovingTransformer {
     List<Statement> replacementStatements = [
       ...node.pattern.declaredVariables,
       ...matchingCache.declarations,
-      // TODO(cstefantsova): Figure out the right exception to throw.
+      // TODO(cstefantsova): Provide a better diagnostic message.
       createIfStatement(
           createNot(readMatchingExpression),
           createExpressionStatement(createThrow(createConstructorInvocation(
-              typeEnvironment.coreTypes.reachabilityErrorConstructor,
-              createArguments([], fileOffset: node.fileOffset),
+              typeEnvironment.coreTypes.stateErrorConstructor,
+              createArguments([
+                createStringLiteral(messagePatternMatchingError.problemMessage,
+                    fileOffset: node.fileOffset)
+              ], fileOffset: node.fileOffset),
               fileOffset: node.fileOffset))),
           fileOffset: node.fileOffset),
     ];

pkg/front_end/testcases/dartdevc/issue51449.dart.strong.expect

@@ -25,7 +25,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t3 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/dartdevc/issue51449.dart.strong.transformed.expect

@@ -25,7 +25,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t3 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/dartdevc/issue51449.dart.weak.expect

@@ -31,7 +31,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t1 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/dartdevc/issue51449.dart.weak.modular.expect

@@ -31,7 +31,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t1 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/dartdevc/issue51449.dart.weak.transformed.expect

@@ -31,7 +31,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t1 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/extensions/explicit_invalid_access.dart.strong.expect

@@ -30,7 +30,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class Class extends core::Object {
   synthetic constructor •() → self::Class
@@ -46,7 +45,7 @@ static method errors(self::Class c) → dynamic {
   block {
     final synthesized dynamic #0#0 = 42;
     if(!true)
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:12:3: Error: Explicit extension application cannot be used as an expression.
   Extension(c) += 42;

pkg/front_end/testcases/extensions/explicit_invalid_access.dart.strong.transformed.expect

@@ -30,7 +30,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class Class extends core::Object {
   synthetic constructor •() → self::Class
@@ -46,7 +45,7 @@ static method errors(self::Class c) → dynamic {
   block {
     final synthesized dynamic #0#0 = 42;
     if(!true)
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:12:3: Error: Explicit extension application cannot be used as an expression.
   Extension(c) += 42;

pkg/front_end/testcases/extensions/explicit_invalid_access.dart.weak.expect

@@ -30,7 +30,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class Class extends core::Object {
   synthetic constructor •() → self::Class
@@ -46,7 +45,7 @@ static method errors(self::Class c) → dynamic {
   block {
     final synthesized dynamic #0#0 = 42;
     if(!true)
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:12:3: Error: Explicit extension application cannot be used as an expression.
   Extension(c) += 42;

pkg/front_end/testcases/extensions/explicit_invalid_access.dart.weak.modular.expect

@@ -30,7 +30,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class Class extends core::Object {
   synthetic constructor •() → self::Class
@@ -46,7 +45,7 @@ static method errors(self::Class c) → dynamic {
   block {
     final synthesized dynamic #0#0 = 42;
     if(!true)
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:12:3: Error: Explicit extension application cannot be used as an expression.
   Extension(c) += 42;

pkg/front_end/testcases/extensions/explicit_invalid_access.dart.weak.transformed.expect

@@ -30,7 +30,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class Class extends core::Object {
   synthetic constructor •() → self::Class
@@ -46,7 +45,7 @@ static method errors(self::Class c) → dynamic {
   block {
     final synthesized dynamic #0#0 = 42;
     if(!true)
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:12:3: Error: Explicit extension application cannot be used as an expression.
   Extension(c) += 42;

pkg/front_end/testcases/general/issue40242.dart.strong.expect

@@ -20,7 +20,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class C extends core::Object {
   synthetic constructor •() → self::C
@@ -50,7 +49,7 @@ static method errors() → dynamic {
   block {
     final synthesized dynamic #0#0 = new self::C::•();
     if(!(let final dynamic #t1 = c2 = #0#0{self::C} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/general/issue40242.dart:20:3: Error: Can't assign to the const variable 'c3'.
   c3 = null;

pkg/front_end/testcases/general/issue40242.dart.strong.transformed.expect

@@ -20,7 +20,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class C extends core::Object {
   synthetic constructor •() → self::C
@@ -50,7 +49,7 @@ static method errors() → dynamic {
   block {
     final synthesized dynamic #0#0 = new self::C::•();
     if(!(let final self::C #t1 = c2 = #0#0{self::C} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/general/issue40242.dart:20:3: Error: Can't assign to the const variable 'c3'.
   c3 = null;

pkg/front_end/testcases/general/issue40242.dart.weak.expect

@@ -20,7 +20,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class C extends core::Object {
   synthetic constructor •() → self::C
@@ -50,7 +49,7 @@ static method errors() → dynamic {
   block {
     final synthesized dynamic #0#0 = new self::C::•();
     if(!(let final dynamic #t1 = c2 = #0#0{self::C} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/general/issue40242.dart:20:3: Error: Can't assign to the const variable 'c3'.
   c3 = null;

pkg/front_end/testcases/general/issue40242.dart.weak.modular.expect

@@ -20,7 +20,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class C extends core::Object {
   synthetic constructor •() → self::C
@@ -50,7 +49,7 @@ static method errors() → dynamic {
   block {
     final synthesized dynamic #0#0 = new self::C::•();
     if(!(let final dynamic #t1 = c2 = #0#0{self::C} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/general/issue40242.dart:20:3: Error: Can't assign to the const variable 'c3'.
   c3 = null;

pkg/front_end/testcases/general/issue40242.dart.weak.transformed.expect

@@ -20,7 +20,6 @@ library /*isNonNullableByDefault*/;
 //
 import self as self;
 import "dart:core" as core;
-import "dart:_internal" as _in;
 
 class C extends core::Object {
   synthetic constructor •() → self::C
@@ -50,7 +49,7 @@ static method errors() → dynamic {
   block {
     final synthesized dynamic #0#0 = new self::C::•();
     if(!(let final self::C #t1 = c2 = #0#0{self::C} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   invalid-expression "pkg/front_end/testcases/general/issue40242.dart:20:3: Error: Can't assign to the const variable 'c3'.
   c3 = null;

pkg/front_end/testcases/late_lowering/issue51449.dart.strong.expect

@@ -25,7 +25,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t3 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/late_lowering/issue51449.dart.strong.transformed.expect

@@ -25,7 +25,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t3 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/late_lowering/issue51449.dart.weak.expect

@@ -31,7 +31,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t1 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/late_lowering/issue51449.dart.weak.modular.expect

@@ -31,7 +31,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t1 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/late_lowering/issue51449.dart.weak.transformed.expect

@@ -31,7 +31,7 @@ static method main() → dynamic {
   block {
     final synthesized dynamic #0#0 = (2, "Hello");
     if(!(let final dynamic #t1 = #j#set(#0#0{(core::int, core::String)}.$1{core::int}){(core::int) → dynamic} in true))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   core::print(#j#get(){() → core::int});
 }

pkg/front_end/testcases/late_lowering/pattern_assignment_final.dart.strong.expect

@@ -81,14 +81,14 @@ static method method(dynamic x, dynamic y, dynamic z) → dynamic {
    ^^^^^^^^^^^^^^^^" && invalid-expression "pkg/front_end/testcases/late_lowering/pattern_assignment_final.dart:32:7: Error: Can't assign to the final variable '#initializedLateFinal'.
       initializedLateFinal, // Error
       ^^^^^^^^^^^^^^^^^^^^^" && (let final dynamic #t5 = definitelyUnassignedFinal = #0#0{(core::Object?, core::Object?, core::Object?)}.$3{core::Object?} in true)))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   block {
     final synthesized dynamic #1#0 = y;
     if(!(#1#0 is{ForNonNullableByDefault} core::List<dynamic> && #1#0{core::List<dynamic>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (let final dynamic #t6 = #definitelyUnassignedLateFinal#set(#1#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} as{ForNonNullableByDefault} core::int?){(core::int) → dynamic} in true) && invalid-expression "pkg/front_end/testcases/late_lowering/pattern_assignment_final.dart:35:5: Error: Final variable 'definitelyAssignedFinal' might already be assigned at this point.
     definitelyAssignedFinal] = y; // Error
     ^^^^^^^^^^^^^^^^^^^^^^^"))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#1#0;
   block {
     final synthesized dynamic #2#0 = z;
@@ -109,7 +109,7 @@ static method method(dynamic x, dynamic y, dynamic z) → dynamic {
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^") && (#2#3#func(){() → dynamic} is{ForNonNullableByDefault} core::List<dynamic> && (#2#3#func(){() → dynamic} as{ForNonNullableByDefault} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (#2#9#func(){() → dynamic} is{ForNonNullableByDefault} core::List<dynamic> && (#2#9#func(){() → dynamic} as{ForNonNullableByDefault} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && invalid-expression "pkg/front_end/testcases/late_lowering/pattern_assignment_final.dart:37:17: Error: Final variable 'notDefinitelyAssignedFinal' might already be assigned at this point.
       field2: [[notDefinitelyAssignedFinal, _], // Error
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^") && (#2#16#func(){() → dynamic} is{ForNonNullableByDefault} core::List<dynamic> && (#2#16#func(){() → dynamic} as{ForNonNullableByDefault} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (let final dynamic #t11 = #notDefinitelyAssignedLateFinal#set((#2#16#func(){() → dynamic} as{ForNonNullableByDefault} core::List<dynamic>).{core::List::[]}(1){(core::int) → dynamic} as{ForNonNullableByDefault} core::int?){(core::int) → dynamic} in true)))))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#2#0;
 }
 

pkg/front_end/testcases/late_lowering/pattern_assignment_final.dart.strong.transformed.expect

@@ -81,14 +81,14 @@ static method method(dynamic x, dynamic y, dynamic z) → dynamic {
    ^^^^^^^^^^^^^^^^" && invalid-expression "pkg/front_end/testcases/late_lowering/pattern_assignment_final.dart:32:7: Error: Can't assign to the final variable '#initializedLateFinal'.
       initializedLateFinal, // Error
       ^^^^^^^^^^^^^^^^^^^^^" && (let final core::Object? #t5 = definitelyUnassignedFinal = #0#0{(core::Object?, core::Object?, core::Object?)}.$3{core::Object?} in true)))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#0#0;
   block {
     final synthesized dynamic #1#0 = y;
     if(!(#1#0 is{ForNonNullableByDefault} core::List<dynamic> && #1#0{core::List<dynamic>}.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (let final dynamic #t6 = #definitelyUnassignedLateFinal#set(#1#0{core::List<dynamic>}.{core::List::[]}(0){(core::int) → dynamic} as{ForNonNullableByDefault} core::int?){(core::int) → dynamic} in true) && invalid-expression "pkg/front_end/testcases/late_lowering/pattern_assignment_final.dart:35:5: Error: Final variable 'definitelyAssignedFinal' might already be assigned at this point.
     definitelyAssignedFinal] = y; // Error
     ^^^^^^^^^^^^^^^^^^^^^^^"))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#1#0;
   block {
     final synthesized dynamic #2#0 = z;
@@ -109,7 +109,7 @@ static method method(dynamic x, dynamic y, dynamic z) → dynamic {
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^") && (#2#3#func(){() → dynamic} is{ForNonNullableByDefault} core::List<dynamic> && (#2#3#func(){() → dynamic} as{ForNonNullableByDefault} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (#2#9#func(){() → dynamic} is{ForNonNullableByDefault} core::List<dynamic> && (#2#9#func(){() → dynamic} as{ForNonNullableByDefault} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && invalid-expression "pkg/front_end/testcases/late_lowering/pattern_assignment_final.dart:37:17: Error: Final variable 'notDefinitelyAssignedFinal' might already be assigned at this point.
       field2: [[notDefinitelyAssignedFinal, _], // Error
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^") && (#2#16#func(){() → dynamic} is{ForNonNullableByDefault} core::List<dynamic> && (#2#16#func(){() → dynamic} as{ForNonNullableByDefault} core::List<dynamic>).{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} #C1 && (let final dynamic #t11 = #notDefinitelyAssignedLateFinal#set((#2#16#func(){() → dynamic} as{ForNonNullableByDefault} core::List<dynamic>).{core::List::[]}(1){(core::int) → dynamic} as{ForNonNullableByDefault} core::int?){(core::int) → dynamic} in true)))))
-      throw new _in::ReachabilityError::•();
+      throw new core::StateError::•("Pattern matching error");
   } =>#2#0;
 }