[ddc] Erase extension types in string concats

nshahan · Commit Queue · commit 8d24f7ebd418 · 2023-12-18T20:56:54.000Z
Ensures the same optimizations to expressions statically typed as extension types. Issue: #49735 Change-Id: I981859562bdd81cf34bd5ed4160a270e6fdff9f3 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/342105 Reviewed-by: Mark Zhou <markzipan@google.com>
diff --git a/pkg/dev_compiler/lib/src/kernel/compiler.dart b/pkg/dev_compiler/lib/src/kernel/compiler.dart
@@ -7173,7 +7173,7 @@ class ProgramCompiler extends ComputeOnceConstantVisitor<js_ast.Expression>
       if (jsExpr is js_ast.LiteralString && jsExpr.valueWithoutQuotes.isEmpty) {
         continue;
       }
-      var type = e.getStaticType(_staticTypeContext);
+      var type = e.getStaticType(_staticTypeContext).extensionTypeErasure;
       if (DartTypeEquivalence(_coreTypes, ignoreTopLevelNullability: true)
               .areEqual(type, _coreTypes.stringNonNullableRawType) &&
           !isNullable(e)) {

Original file line number	Diff line number	Diff line change
`@@ -7173,7 +7173,7 @@ class ProgramCompiler extends ComputeOnceConstantVisitor<js_ast.Expression>`
`7173`	`7173`	`if (jsExpr is js_ast.LiteralString && jsExpr.valueWithoutQuotes.isEmpty) {`
`7174`	`7174`	`continue;`
`7175`	`7175`	`}`
`7176`		`- var type = e.getStaticType(_staticTypeContext);`
	`7176`	`+ var type = e.getStaticType(_staticTypeContext).extensionTypeErasure;`
`7177`	`7177`	`if (DartTypeEquivalence(_coreTypes, ignoreTopLevelNullability: true)`
`7178`	`7178`	`.areEqual(type, _coreTypes.stringNonNullableRawType) &&`
`7179`	`7179`	`!isNullable(e)) {`