Revert incorrect commit character change; make test 21 manual

Reverts the change in computeCommitCharactersAndIsNewIdentifier that
incorrectly switched TupleType and IndexSignature to emptyCommitCharacters.
The original TypeScript code uses allCommitCharacters for all four kinds
(ArrayLiteralExpression, IndexSignature, TupleType, ComputedPropertyName).

The test expectation mismatch was caused by the Go test generator mapping
isNewIdentifierLocation:true to empty commit characters, which is incorrect
for this context. Made test 21 manual with the correct DefaultCommitCharacters.

Co-authored-by: jakebailey <5341706+jakebailey@users.noreply.github.com>

Author: Copilot

internal/fourslash/_scripts/manualTests.txt

@@ -21,6 +21,7 @@ completionImportModuleSpecifierEndingTsxPreserve
 completionImportModuleSpecifierEndingTsxReact
 completionListInClosedFunction05
 completionListInImportClause05
+completionListInTypeLiteralInTypeParameter21
 completionListWithLabel
 completionsAtIncompleteObjectLiteralProperty
 completionsImport_defaultAndNamedConflict

…stInTypeLiteralInTypeParameter21_test.go …stInTypeLiteralInTypeParameter21_test.gointernal/fourslash/tests/gen/completionListInTypeLiteralInTypeParameter21_test.go renamed to internal/fourslash/tests/manual/completionListInTypeLiteralInTypeParameter21_test.go internal/fourslash/tests/gen/completionListInTypeLiteralInTypeParameter21_test.go renamed to internal/fourslash/tests/manual/completionListInTypeLiteralInTypeParameter21_test.go

@@ -9,7 +9,7 @@ import (
 )
 
 func TestCompletionListInTypeLiteralInTypeParameter21(t *testing.T) {
-	fourslash.SkipIfFailing(t)
+
 	t.Parallel()
 	defer testutil.RecoverAndFail(t, "Panic on fourslash test")
 	const content = `class Foo<T extends ('one' | 2)[]> {}
@@ -25,7 +25,7 @@ Foo<[/*4*/]>;`
 	f.VerifyCompletions(t, "0", &fourslash.CompletionsExpectedList{
 		IsIncomplete: false,
 		ItemDefaults: &fourslash.CompletionsExpectedItemDefaults{
-			CommitCharacters: &[]string{},
+			CommitCharacters: &DefaultCommitCharacters,
 			EditRange:        Ignored,
 		},
 		Items: &fourslash.CompletionsExpectedItems{
@@ -38,7 +38,7 @@ Foo<[/*4*/]>;`
 	f.VerifyCompletions(t, "1", &fourslash.CompletionsExpectedList{
 		IsIncomplete: false,
 		ItemDefaults: &fourslash.CompletionsExpectedItemDefaults{
-			CommitCharacters: &[]string{},
+			CommitCharacters: &DefaultCommitCharacters,
 			EditRange:        Ignored,
 		},
 		Items: &fourslash.CompletionsExpectedItems{
@@ -51,7 +51,7 @@ Foo<[/*4*/]>;`
 	f.VerifyCompletions(t, "2", &fourslash.CompletionsExpectedList{
 		IsIncomplete: false,
 		ItemDefaults: &fourslash.CompletionsExpectedItemDefaults{
-			CommitCharacters: &[]string{},
+			CommitCharacters: &DefaultCommitCharacters,
 			EditRange:        Ignored,
 		},
 		Items: &fourslash.CompletionsExpectedItems{
@@ -64,7 +64,7 @@ Foo<[/*4*/]>;`
 	f.VerifyCompletions(t, "3", &fourslash.CompletionsExpectedList{
 		IsIncomplete: false,
 		ItemDefaults: &fourslash.CompletionsExpectedItemDefaults{
-			CommitCharacters: &[]string{},
+			CommitCharacters: &DefaultCommitCharacters,
 			EditRange:        Ignored,
 		},
 		Items: &fourslash.CompletionsExpectedItems{
@@ -77,7 +77,7 @@ Foo<[/*4*/]>;`
 	f.VerifyCompletions(t, "4", &fourslash.CompletionsExpectedList{
 		IsIncomplete: false,
 		ItemDefaults: &fourslash.CompletionsExpectedItemDefaults{
-			CommitCharacters: &[]string{},
+			CommitCharacters: &DefaultCommitCharacters,
 			EditRange:        Ignored,
 		},
 		Items: &fourslash.CompletionsExpectedItems{

internal/ls/completions.go

@@ -3492,13 +3492,11 @@ func computeCommitCharactersAndIsNewIdentifier(
 	case ast.KindOpenBracketToken:
 		switch containingNodeKind {
 		// [ |
-		case ast.KindArrayLiteralExpression, ast.KindComputedPropertyName:
-			return true, allCommitCharacters
 		// [ | : string ]
 		// [ | : string ]
 		// [ |    /* this can become an index signature */
-		case ast.KindIndexSignature, ast.KindTupleType:
-			return true, emptyCommitCharacters
+		case ast.KindArrayLiteralExpression, ast.KindIndexSignature, ast.KindTupleType, ast.KindComputedPropertyName:
+			return true, allCommitCharacters
 		default:
 			return false, allCommitCharacters
 		}