From 502d61dc9fb9bc72edbb56be848e92d4ad17a506 Mon Sep 17 00:00:00 2001
From: Cameron <cameron.clark@hey.com>
Date: Sat, 2 Dec 2023 07:44:25 +0000
Subject: [PATCH] fix(prettier) fix use chain formatting (#1605)

---
 crates/oxc_prettier/src/format/assignment.rs | 21 ++++++++++----------
 crates/oxc_prettier/src/lib.rs               |  1 +
 tasks/prettier_conformance/prettier.snap.md  |  3 +--
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/crates/oxc_prettier/src/format/assignment.rs b/crates/oxc_prettier/src/format/assignment.rs
index fe938878a..850f5bbec 100644
--- a/crates/oxc_prettier/src/format/assignment.rs
+++ b/crates/oxc_prettier/src/format/assignment.rs
@@ -146,16 +146,17 @@ fn choose_layout<'a>(
 
     let is_tail = !is_assignment(right_expr);
 
-    let should_use_chain_formatting = matches!(p.parent_kind(), AstKind::AssignmentExpression(_))
-        && matches!(
-            p.parent_parent_kind(),
-            Some(AstKind::AssignmentExpression(_) | AstKind::VariableDeclarator(_))
-        )
-        && (!is_tail
-            || !matches!(
-                p.nth_parent_kind(3),
-                Some(AstKind::ExpressionStatement(_) | AstKind::VariableDeclaration(_))
-            ));
+    let should_use_chain_formatting =
+        matches!(assignment_like_node, AssignmentLikeNode::AssignmentExpression(_))
+            && matches!(
+                p.parent_kind(),
+                AstKind::AssignmentExpression(_) | AstKind::VariableDeclarator(_)
+            )
+            && (!is_tail
+                || !matches!(
+                    p.parent_parent_kind(),
+                    Some(AstKind::ExpressionStatement(_) | AstKind::VariableDeclaration(_))
+                ));
 
     if should_use_chain_formatting {
         if !is_tail {
diff --git a/crates/oxc_prettier/src/lib.rs b/crates/oxc_prettier/src/lib.rs
index fb81ad34a..e851eeda7 100644
--- a/crates/oxc_prettier/src/lib.rs
+++ b/crates/oxc_prettier/src/lib.rs
@@ -108,6 +108,7 @@ impl<'a> Prettier<'a> {
         (len >= 3).then(|| self.nodes[len - 3])
     }
 
+    #[allow(unused)]
     fn nth_parent_kind(&self, n: usize) -> Option<AstKind<'a>> {
         let len = self.nodes.len();
         (len > n).then(|| self.nodes[len - n - 1])
diff --git a/tasks/prettier_conformance/prettier.snap.md b/tasks/prettier_conformance/prettier.snap.md
index 2f44845eb..7ebd6df1c 100644
--- a/tasks/prettier_conformance/prettier.snap.md
+++ b/tasks/prettier_conformance/prettier.snap.md
@@ -1,4 +1,4 @@
-Compatibility: 216/561 (38.50%)
+Compatibility: 217/561 (38.68%)
 
 # Failed
 
@@ -48,7 +48,6 @@ Compatibility: 216/561 (38.50%)
 * assignment/issue-15534.js
 * assignment/issue-2482-2.js
 * assignment/issue-2540.js
-* assignment/issue-3819.js
 * assignment/issue-6922.js
 * assignment/issue-7572.js
 * assignment/lone-arg.js