fix(47582): skip extraction if the type node is in the range of the type parameter declaration

Author: a-tarasyuk

src/services/refactors/extractType.ts

@@ -145,8 +145,13 @@ namespace ts.refactor {
             if (isTypeReferenceNode(node)) {
                 if (isIdentifier(node.typeName)) {
                     const symbol = checker.resolveName(node.typeName.text, node.typeName, SymbolFlags.TypeParameter, /* excludeGlobals */ true);
-                    const declaration = tryCast(symbol?.declarations?.[0], isTypeParameterDeclaration);
+                    const declaration = firstDefined(symbol?.declarations, d => isTypeParameterDeclaration(d) && d.getSourceFile() === file ? d : undefined);
                     if (declaration) {
+                        if (declaration.name.escapedText === node.typeName.escapedText && rangeContainsSkipTrivia(declaration, selection, file)) {
+                            // skip extraction if the type node is in the range of the type parameter declaration.
+                            // function foo<T extends { a?: /**/T }>(): void;
+                            return true;
+                        }
                         if (rangeContainsSkipTrivia(statement, declaration, file) && !rangeContainsSkipTrivia(selection, declaration, file)) {
                             pushIfUnique(result, declaration);
                         }

tests/cases/fourslash/refactorExtractType72.ts

@@ -0,0 +1,6 @@
+/// <reference path='fourslash.ts' />
+
+////export declare function foo<T extends { a?: /*a*/T/*b*/ }>(): void;
+
+goTo.select("a", "b");
+verify.not.refactorAvailable("Extract type", "Extract to type alias");

tests/cases/fourslash/refactorExtractType73.ts

@@ -0,0 +1,11 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: a.ts
+////interface Foo<T extends { prop: T }> {}
+
+// @Filename: b.ts
+////interface Foo<T extends { prop: /*a*/T/*b*/ }> {}
+
+goTo.file("b.ts");
+goTo.select("a", "b");
+verify.not.refactorAvailable("Extract type", "Extract to type alias");

tests/cases/fourslash/refactorExtractType74.ts

@@ -0,0 +1,15 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: a.ts
+//// interface Foo<T extends { prop: [|T|] }> {}
+
+// @Filename: b.ts
+//// // Some initial comments.
+//// // We need to ensure these files have different contents,
+//// // so their ranges differ, so we'll start a few lines below in this file.
+//// interface Foo<T extends { prop: [|T|] }> {}
+
+for (const range of test.ranges()) {
+    goTo.selectRange(range);
+    verify.not.refactorAvailable("Extract type", "Extract to type alias");
+}