feat(formatter): implement formatting for TSTypeAssertion (#13911)

Author: Dunqing

crates/oxc_formatter/src/write/mod.rs

@@ -45,7 +45,7 @@ use oxc_ast::{AstKind, ast::*};
 use oxc_span::GetSpan;
 
 use crate::{
-    format_args,
+    best_fitting, format_args,
     formatter::{
         Buffer, Format, FormatResult, Formatter,
         prelude::*,
@@ -1968,13 +1968,37 @@ impl<'a> FormatWrite<'a> for AstNode<'a, TSMappedType<'a>> {
 
 impl<'a> FormatWrite<'a> for AstNode<'a, TSTypeAssertion<'a>> {
     fn write(&self, f: &mut Formatter<'_, 'a>) -> FormatResult<()> {
-        write!(f, "<")?;
-        // var r = < <T>(x: T) => T > ((x) => { return null; });
-        //          ^ make sure space is printed here.
-        if matches!(**self.type_annotation(), TSType::TSFunctionType(_)) {
-            write!(f, space())?;
+        let break_after_cast = !matches!(
+            self.expression,
+            Expression::ArrayExpression(_) | Expression::ObjectExpression(_)
+        );
+
+        let format_cast = format_with(|f| {
+            write!(f, ["<", group(&soft_block_indent(&self.type_annotation())), ">",])
+        });
+
+        if break_after_cast {
+            let format_cast = format_cast.memoized();
+            let format_expression = self.expression().memoized();
+
+            write!(
+                f,
+                [best_fitting![
+                    format_args!(format_cast, format_expression),
+                    format_args!(
+                        format_cast,
+                        group(&format_args!(
+                            text("("),
+                            block_indent(&format_expression),
+                            text(")")
+                        ))
+                    ),
+                    format_args!(format_cast, format_expression)
+                ]]
+            )
+        } else {
+            write!(f, [format_cast, self.expression()])
         }
-        write!(f, [self.type_annotation(), ">", self.expression()])
     }
 }
 

tasks/coverage/snapshots/formatter_typescript.snap

@@ -2,7 +2,7 @@ commit: 261630d6
 
 formatter_typescript Summary:
 AST Parsed     : 8816/8816 (100.00%)
-Positive Passed: 8789/8816 (99.69%)
+Positive Passed: 8788/8816 (99.68%)
 Mismatch: tasks/coverage/typescript/tests/cases/compiler/amdLikeInputDeclarationEmit.ts
 
 Expect to Parse: tasks/coverage/typescript/tests/cases/compiler/arrayFromAsync.ts
@@ -17,6 +17,8 @@ Mismatch: tasks/coverage/typescript/tests/cases/compiler/declarationEmitCastReus
 
 Mismatch: tasks/coverage/typescript/tests/cases/compiler/declarationEmitShadowingInferNotRenamed.ts
 
+Expect to Parse: tasks/coverage/typescript/tests/cases/compiler/genericTypeAssertions3.ts
+Unexpected token
 Mismatch: tasks/coverage/typescript/tests/cases/compiler/jsxNamespaceGlobalReexport.tsx
 
 Mismatch: tasks/coverage/typescript/tests/cases/compiler/jsxNamespaceGlobalReexportMissingAliasTarget.tsx

tasks/prettier_conformance/snapshots/prettier.ts.snap.md

@@ -1,4 +1,4 @@
-ts compatibility: 417/573 (72.77%)
+ts compatibility: 419/573 (73.12%)
 
 # Failed
 
@@ -21,7 +21,7 @@ ts compatibility: 417/573 (72.77%)
 | typescript/assignment/issue-10846.ts | 💥 | 57.14% |
 | typescript/assignment/issue-10848.tsx | 💥 | 52.12% |
 | typescript/assignment/issue-10850.ts | 💥 | 50.00% |
-| typescript/cast/generic-cast.ts | 💥 | 39.24% |
+| typescript/cast/generic-cast.ts | 💥 | 81.48% |
 | typescript/cast/tuple-and-record.ts | 💥 | 0.00% |
 | typescript/chain-expression/call-expression.ts | 💥 | 68.75% |
 | typescript/chain-expression/member-expression.ts | 💥 | 65.67% |
@@ -42,7 +42,6 @@ ts compatibility: 417/573 (72.77%)
 | typescript/comments/type_literals.ts | 💥 | 68.97% |
 | typescript/comments/union.ts | 💥 | 75.00% |
 | typescript/compiler/anyIsAssignableToObject.ts | 💥 | 75.00% |
-| typescript/compiler/castTest.ts | 💥 | 96.67% |
 | typescript/compiler/contextualSignatureInstantiation2.ts | 💥 | 88.89% |
 | typescript/compiler/indexSignatureWithInitializer.ts | 💥 | 75.00% |
 | typescript/compiler/mappedTypeWithCombinedTypeMappers.ts | 💥 | 91.89% |
@@ -147,7 +146,6 @@ ts compatibility: 417/573 (72.77%)
 | typescript/type-arguments-bit-shift-left-like/3.ts | 💥 | 0.00% |
 | typescript/type-arguments-bit-shift-left-like/5.tsx | 💥 | 0.00% |
 | typescript/typeof/typeof.ts | 💥 | 25.00% |
-| typescript/typeparams/class-method.ts | 💥 | 96.61% |
 | typescript/typeparams/const.ts | 💥 | 86.15% |
 | typescript/typeparams/line-breaking-after-extends-2.ts | 💥 | 20.00% |
 | typescript/typeparams/line-breaking-after-extends.ts | 💥 | 17.14% |