diff --git a/crates/oxc_ast/src/ast_impl/js.rs b/crates/oxc_ast/src/ast_impl/js.rs
index ee87813dfa52b..ca9760b525e05 100644
--- a/crates/oxc_ast/src/ast_impl/js.rs
+++ b/crates/oxc_ast/src/ast_impl/js.rs
@@ -983,6 +983,21 @@ impl<'a> AssignmentTargetMaybeDefault<'a> {
             _ => None,
         }
     }
+
+    /// Returns mut identifier bound by this assignment target.
+    pub fn identifier_mut(&mut self) -> Option<&mut IdentifierReference<'a>> {
+        match self {
+            AssignmentTargetMaybeDefault::AssignmentTargetIdentifier(id) => Some(id),
+            Self::AssignmentTargetWithDefault(target) => {
+                if let AssignmentTarget::AssignmentTargetIdentifier(id) = &mut target.binding {
+                    Some(id)
+                } else {
+                    None
+                }
+            }
+            _ => None,
+        }
+    }
 }
 
 impl Statement<'_> {
diff --git a/crates/oxc_minifier/src/ctx.rs b/crates/oxc_minifier/src/ctx.rs
index b1aa1e209d0b4..7003556d311ad 100644
--- a/crates/oxc_minifier/src/ctx.rs
+++ b/crates/oxc_minifier/src/ctx.rs
@@ -50,7 +50,9 @@ impl<'a> oxc_ecmascript::is_global_reference::IsGlobalReference<'a> for Ctx<'a,
         self.scoping()
             .get_reference(reference_id)
             .symbol_id()
-            .and_then(|symbol_id| self.state.symbol_values.get_constant_value(symbol_id))
+            .and_then(|symbol_id| self.state.symbol_values.get_symbol_value(symbol_id))
+            .filter(|sv| sv.write_references_count == 0)
+            .and_then(|sv| sv.initialized_constant.as_ref())
             .cloned()
     }
 }
@@ -164,7 +166,23 @@ impl<'a> Ctx<'a, '_> {
         false
     }
 
-    pub fn init_value(&mut self, symbol_id: SymbolId, constant: ConstantValue<'a>) {
+    pub fn init_value(&mut self, symbol_id: SymbolId, constant: Option<ConstantValue<'a>>) {
+        let mut exported = false;
+        if self.scoping.current_scope_id() == self.scoping().root_scope_id() {
+            for ancestor in self.ancestors() {
+                if ancestor.is_export_named_declaration()
+                    || ancestor.is_export_all_declaration()
+                    || ancestor.is_export_default_declaration()
+                {
+                    exported = true;
+                }
+            }
+        }
+
+        let for_statement_init = self.ancestors().nth(1).is_some_and(|ancestor| {
+            ancestor.is_parent_of_for_statement_init() || ancestor.is_parent_of_for_statement_left()
+        });
+
         let mut read_references_count = 0;
         let mut write_references_count = 0;
         for r in self.scoping().get_resolved_references(symbol_id) {
@@ -177,8 +195,14 @@ impl<'a> Ctx<'a, '_> {
         }
 
         let scope_id = self.scoping.current_scope_id();
-        let symbol_value =
-            SymbolValue { constant, read_references_count, write_references_count, scope_id };
+        let symbol_value = SymbolValue {
+            initialized_constant: constant,
+            exported,
+            for_statement_init,
+            read_references_count,
+            write_references_count,
+            scope_id,
+        };
         self.state.symbol_values.init_value(symbol_id, symbol_value);
     }
 
diff --git a/crates/oxc_minifier/src/peephole/inline.rs b/crates/oxc_minifier/src/peephole/inline.rs
index 0f35c9ae555c6..71731546cf4c0 100644
--- a/crates/oxc_minifier/src/peephole/inline.rs
+++ b/crates/oxc_minifier/src/peephole/inline.rs
@@ -1,5 +1,5 @@
 use oxc_ast::ast::*;
-use oxc_ecmascript::constant_evaluation::ConstantEvaluation;
+use oxc_ecmascript::constant_evaluation::{ConstantEvaluation, ConstantValue};
 use oxc_span::GetSpan;
 
 use crate::ctx::Ctx;
@@ -10,11 +10,12 @@ impl<'a> PeepholeOptimizations {
     pub fn init_symbol_value(&self, decl: &VariableDeclarator<'a>, ctx: &mut Ctx<'a, '_>) {
         let BindingPatternKind::BindingIdentifier(ident) = &decl.id.kind else { return };
         let Some(symbol_id) = ident.symbol_id.get() else { return };
-        // Skip if not `const` variable.
-        if !ctx.scoping().symbol_flags(symbol_id).is_const_variable() {
+        // Skip for `var` declarations, due to TDZ problems.
+        if decl.kind.is_var() {
             return;
         }
-        let Some(value) = decl.init.evaluate_value(ctx) else { return };
+        let value =
+            decl.init.as_ref().map_or(Some(ConstantValue::Undefined), |e| e.evaluate_value(ctx));
         ctx.init_value(symbol_id, value);
     }
 
@@ -33,7 +34,11 @@ impl<'a> PeepholeOptimizations {
         if symbol_value.write_references_count > 0 {
             return;
         }
-        *expr = ctx.value_to_expr(expr.span(), symbol_value.constant.clone());
+        if symbol_value.for_statement_init {
+            return;
+        }
+        let Some(cv) = &symbol_value.initialized_constant else { return };
+        *expr = ctx.value_to_expr(expr.span(), cv.clone());
         ctx.state.changed = true;
     }
 }
diff --git a/crates/oxc_minifier/src/peephole/minimize_conditions.rs b/crates/oxc_minifier/src/peephole/minimize_conditions.rs
index 44e8964b6d1b1..2c624985fbfc1 100644
--- a/crates/oxc_minifier/src/peephole/minimize_conditions.rs
+++ b/crates/oxc_minifier/src/peephole/minimize_conditions.rs
@@ -526,8 +526,9 @@ mod test {
         // In the following test case, we can't remove the duplicate "alert(x);" lines since each "x"
         // refers to a different variable.
         // We only try removing duplicate statements if the AST is normalized and names are unique.
-        test_same(
+        test(
             "if (Math.random() < 0.5) { let x = 3; alert(x); } else { let x = 5; alert(x); }",
+            "if (Math.random() < 0.5) { let x = 3; alert(3); } else { let x = 5; alert(5); }",
         );
     }
 
diff --git a/crates/oxc_minifier/src/peephole/normalize.rs b/crates/oxc_minifier/src/peephole/normalize.rs
index 7e87a3e7a88ed..1a13fe7442749 100644
--- a/crates/oxc_minifier/src/peephole/normalize.rs
+++ b/crates/oxc_minifier/src/peephole/normalize.rs
@@ -454,7 +454,8 @@ mod test {
     #[test]
     fn fold_number_nan() {
         test("foo(Number.NaN)", "foo(NaN)");
-        test_same("let Number; foo(Number.NaN)");
+        test_same("var Number; foo(Number.NaN)");
+        test_same("let Number; foo((void 0).NaN)");
     }
 
     #[test]
diff --git a/crates/oxc_minifier/src/peephole/remove_unused_variable_declaration.rs b/crates/oxc_minifier/src/peephole/remove_unused_variable_declaration.rs
index 109886bbde214..2c3ace496d767 100644
--- a/crates/oxc_minifier/src/peephole/remove_unused_variable_declaration.rs
+++ b/crates/oxc_minifier/src/peephole/remove_unused_variable_declaration.rs
@@ -1,3 +1,4 @@
+use oxc_allocator::TakeIn;
 use oxc_ast::ast::*;
 
 use crate::{CompressOptionsUnused, ctx::Ctx};
@@ -88,37 +89,47 @@ impl<'a> PeepholeOptimizations {
 
     pub fn remove_unused_assignment_expression(
         &self,
-        _e: &mut Expression<'a>,
-        _ctx: &mut Ctx<'a, '_>,
+        e: &mut Expression<'a>,
+        ctx: &mut Ctx<'a, '_>,
     ) -> bool {
-        // let Expression::AssignmentExpression(assign_expr) = e else { return false };
-        // if matches!(
-        // ctx.state.options.unused,
-        // CompressOptionsUnused::Keep | CompressOptionsUnused::KeepAssign
-        // ) {
-        // return false;
-        // }
-        // let Some(SimpleAssignmentTarget::AssignmentTargetIdentifier(ident)) =
-        // assign_expr.left.as_simple_assignment_target()
-        // else {
-        // return false;
-        // };
-        // if Self::keep_top_level_var_in_script_mode(ctx) {
-        // return false;
-        // }
-        // let Some(reference_id) = ident.reference_id.get() else { return false };
-        // let Some(symbol_id) = ctx.scoping().get_reference(reference_id).symbol_id() else {
-        // return false;
-        // };
-        // // Keep error for assigning to `const foo = 1; foo = 2`.
-        // if ctx.scoping().symbol_flags(symbol_id).is_const_variable() {
-        // return false;
-        // }
-        // if !ctx.scoping().get_resolved_references(symbol_id).all(|r| !r.flags().is_read()) {
-        // return false;
-        // }
-        // *e = assign_expr.right.take_in(ctx.ast);
-        // state.changed = true;
+        let Expression::AssignmentExpression(assign_expr) = e else { return false };
+        if matches!(
+            ctx.state.options.unused,
+            CompressOptionsUnused::Keep | CompressOptionsUnused::KeepAssign
+        ) {
+            return false;
+        }
+        let Some(SimpleAssignmentTarget::AssignmentTargetIdentifier(ident)) =
+            assign_expr.left.as_simple_assignment_target()
+        else {
+            return false;
+        };
+        if Self::keep_top_level_var_in_script_mode(ctx) {
+            return false;
+        }
+        let Some(reference_id) = ident.reference_id.get() else { return false };
+        let Some(symbol_id) = ctx.scoping().get_reference(reference_id).symbol_id() else {
+            return false;
+        };
+        // Keep error for assigning to `const foo = 1; foo = 2`.
+        if ctx.scoping().symbol_flags(symbol_id).is_const_variable() {
+            return false;
+        }
+        let Some(symbol_value) = ctx.state.symbol_values.get_symbol_value(symbol_id) else {
+            return false;
+        };
+        // Cannot remove assignment to live bindings: `export let foo; foo = 1;`.
+        if symbol_value.exported {
+            return false;
+        }
+        if symbol_value.read_references_count > 0 {
+            return false;
+        }
+        if symbol_value.for_statement_init {
+            return false;
+        }
+        *e = assign_expr.right.take_in(ctx.ast);
+        ctx.state.changed = true;
         false
     }
 
@@ -180,23 +191,39 @@ mod test {
     }
 
     #[test]
-    #[ignore]
     fn remove_unused_assignment_expression() {
         let options = CompressOptions::smallest();
-        test_options("var x = 1; x = 2;", "", &options);
-        test_options("var x = 1; x = 2;", "", &options);
-        test_options("var x = 1; x = foo();", "foo()", &options);
-        test_same_options("export let foo; foo = 0;", &options);
+        // Vars are not handled yet due to TDZ.
+        test_same_options("var x = 1; x = 2;", &options);
+        test_same_options("var x = 1; x = foo();", &options);
+        test_same_options("export var foo; foo = 0;", &options);
         test_same_options("var x = 1; x = 2, foo(x)", &options);
         test_same_options("function foo() { return t = x(); } foo();", &options);
+        test_same_options("function foo() { var t; return t = x(); } foo();", &options);
+        test_same_options("function foo(t) { return t = x(); } foo();", &options);
+
+        test_options("let x = 1; x = 2;", "", &options);
+        test_options("let x = 1; x = foo();", "foo()", &options);
+        test_same_options("export let foo; foo = 0;", &options);
+        test_same_options("let x = 1; x = 2, foo(x)", &options);
+        test_same_options("function foo() { return t = x(); } foo();", &options);
         test_options(
-            "function foo() { var t; return t = x(); } foo();",
-            "function foo() { return x(); } foo();",
+            "function foo() { let t; return t = x(); } foo();",
+            "function foo() { return x() } foo()",
             &options,
         );
-        test_options(
-            "function foo(t) { return t = x(); } foo();",
-            "function foo(t) { return x(); } foo();",
+        test_same_options("function foo(t) { return t = x(); } foo();", &options);
+
+        test_same_options("for(let i;;) foo(i)", &options);
+        test_same_options("for(let i in []) foo(i)", &options);
+
+        test_options("var a; ({ a: a } = {})", "var a; ({ a } = {})", &options);
+        test_options("var a; b = ({ a: a })", "var a; b = ({ a })", &options);
+
+        test_options("let foo = {}; foo = 1", "", &options);
+
+        test_same_options(
+            "let bracketed = !1; for(;;) bracketed = !bracketed, log(bracketed)",
             &options,
         );
 
@@ -204,9 +231,8 @@ mod test {
         let source_type = SourceType::cjs();
         test_same_options_source_type("var x = 1; x = 2;", source_type, &options);
         test_same_options_source_type("var x = 1; x = 2, foo(x)", source_type, &options);
-        test_options_source_type(
-            "function foo() { var x = 1; x = 2; bar() } foo()",
-            "function foo() { bar() } foo()",
+        test_same_options_source_type(
+            "function foo() { var x = 1; x = 2, bar() } foo()",
             source_type,
             &options,
         );
diff --git a/crates/oxc_minifier/src/peephole/substitute_alternate_syntax.rs b/crates/oxc_minifier/src/peephole/substitute_alternate_syntax.rs
index f16bfc8959a13..097b6e3ade63b 100644
--- a/crates/oxc_minifier/src/peephole/substitute_alternate_syntax.rs
+++ b/crates/oxc_minifier/src/peephole/substitute_alternate_syntax.rs
@@ -40,7 +40,6 @@ impl<'a> PeepholeOptimizations {
     pub fn substitute_assignment_target_property_property(
         &self,
         prop: &mut AssignmentTargetPropertyProperty<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         self.try_compress_property_key(&mut prop.name, &mut prop.computed, ctx);
@@ -49,7 +48,6 @@ impl<'a> PeepholeOptimizations {
     pub fn substitute_assignment_target_property(
         &self,
         prop: &mut AssignmentTargetProperty<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         self.try_compress_assignment_target_property(prop, ctx);
@@ -58,7 +56,6 @@ impl<'a> PeepholeOptimizations {
     pub fn try_compress_assignment_target_property(
         &self,
         prop: &mut AssignmentTargetProperty<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         // `a: a` -> `a`
@@ -66,16 +63,13 @@ impl<'a> PeepholeOptimizations {
             prop
         {
             let Some(prop_name) = assign_target_prop_prop.name.static_name() else { return };
-            let Some(binding_identifier) = assign_target_prop_prop.binding.identifier() else {
+            let Some(ident) = assign_target_prop_prop.binding.identifier_mut() else {
                 return;
             };
-            if prop_name == binding_identifier.name {
+            if prop_name == ident.name {
                 *prop = ctx.ast.assignment_target_property_assignment_target_property_identifier(
-                    assign_target_prop_prop.span,
-                    ctx.ast.identifier_reference(
-                        assign_target_prop_prop.span,
-                        binding_identifier.name,
-                    ),
+                    ident.span,
+                    ident.take_in(ctx.ast),
                     None,
                 );
                 ctx.state.changed = true;
@@ -86,7 +80,6 @@ impl<'a> PeepholeOptimizations {
     pub fn substitute_binding_property(
         &self,
         prop: &mut BindingProperty<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         self.try_compress_property_key(&mut prop.key, &mut prop.computed, ctx);
@@ -95,7 +88,6 @@ impl<'a> PeepholeOptimizations {
     pub fn substitute_method_definition(
         &self,
         prop: &mut MethodDefinition<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         let property_key_parent: ClassPropertyKeyParent = prop.into();
@@ -110,7 +102,6 @@ impl<'a> PeepholeOptimizations {
     pub fn substitute_property_definition(
         &self,
         prop: &mut PropertyDefinition<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         let property_key_parent: ClassPropertyKeyParent = prop.into();
@@ -125,7 +116,6 @@ impl<'a> PeepholeOptimizations {
     pub fn substitute_accessor_property(
         &self,
         prop: &mut AccessorProperty<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         let property_key_parent: ClassPropertyKeyParent = prop.into();
@@ -140,7 +130,6 @@ impl<'a> PeepholeOptimizations {
     pub fn substitute_return_statement(
         &self,
         stmt: &mut ReturnStatement<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         self.compress_return_statement(stmt, ctx);
@@ -149,7 +138,6 @@ impl<'a> PeepholeOptimizations {
     pub fn substitute_variable_declaration(
         &self,
         decl: &mut VariableDeclaration<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         for declarator in &mut decl.declarations {
@@ -218,7 +206,6 @@ impl<'a> PeepholeOptimizations {
     fn try_compress_arrow_expression(
         &self,
         arrow_expr: &mut ArrowFunctionExpression<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         if !arrow_expr.expression
@@ -603,7 +590,6 @@ impl<'a> PeepholeOptimizations {
     fn compress_variable_declarator(
         &self,
         decl: &mut VariableDeclarator<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         // Destructuring Pattern has error throwing side effect.
@@ -859,7 +845,6 @@ impl<'a> PeepholeOptimizations {
     fn try_compress_chain_call_expression(
         &self,
         chain_expr: &mut ChainExpression<'a>,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         if let ChainElement::CallExpression(call_expr) = &mut chain_expr.expression {
@@ -890,7 +875,6 @@ impl<'a> PeepholeOptimizations {
         &self,
         key: &mut PropertyKey<'a>,
         computed: &mut bool,
-
         ctx: &mut Ctx<'a, '_>,
     ) {
         if let PropertyKey::NumericLiteral(_) = key {
diff --git a/crates/oxc_minifier/src/symbol_value.rs b/crates/oxc_minifier/src/symbol_value.rs
index e530a50a6985b..04e367a689330 100644
--- a/crates/oxc_minifier/src/symbol_value.rs
+++ b/crates/oxc_minifier/src/symbol_value.rs
@@ -5,8 +5,15 @@ use oxc_syntax::{scope::ScopeId, symbol::SymbolId};
 
 #[derive(Debug)]
 pub struct SymbolValue<'a> {
-    /// Constant value evaluated from expressions.
-    pub constant: ConstantValue<'a>,
+    /// Initialized constant value evaluated from expressions.
+    /// `None` when the value is not a constant evaluated value.
+    pub initialized_constant: Option<ConstantValue<'a>>,
+
+    /// Symbol is exported.
+    pub exported: bool,
+
+    /// Inside for statement initializer.
+    pub for_statement_init: bool,
 
     pub read_references_count: u32,
     pub write_references_count: u32,
@@ -29,10 +36,6 @@ impl<'a> SymbolValues<'a> {
         self.values.insert(symbol_id, symbol_value);
     }
 
-    pub fn get_constant_value(&self, symbol_id: SymbolId) -> Option<&ConstantValue<'a>> {
-        self.values.get(&symbol_id).map(|v| &v.constant)
-    }
-
     pub fn get_symbol_value(&self, symbol_id: SymbolId) -> Option<&SymbolValue<'a>> {
         self.values.get(&symbol_id)
     }
diff --git a/crates/oxc_minifier/tests/peephole/collapse_variable_declarations.rs b/crates/oxc_minifier/tests/peephole/collapse_variable_declarations.rs
index 71c2831717d4f..457dae2123ae2 100644
--- a/crates/oxc_minifier/tests/peephole/collapse_variable_declarations.rs
+++ b/crates/oxc_minifier/tests/peephole/collapse_variable_declarations.rs
@@ -105,30 +105,30 @@ mod join_vars {
     fn test_redeclaration_let_in_function() {
         test(
             "function f() { let x = 1; let y = 2; let z = 3; x + y + z; }",
-            "function f() { let x = 1, y = 2, z = 3; x + y + z; } ",
+            "function f() { let x = 1, y = 2, z = 3; } ",
         );
 
         // recognize local scope version of x
         test(
             "var x = 1; function f() { let x = 1; let y = 2; x + y; }",
-            "var x = 1; function f() { let x = 1, y = 2; x + y } ",
+            "var x = 1; function f() { let x = 1, y = 2; } ",
         );
 
         // do not redeclare function parameters
         // incompatible with strict mode
-        test_same("function f(x) { let y = 3; x = 4, x + y; }");
+        test(
+            "function f(x) { let y = 3; x = 4, x + y; }",
+            "function f(x) { let y = 3; x = 4, x + 3 }",
+        );
     }
 
     #[test]
     fn test_arrow_function() {
-        test(
-            "(() => { let x = 1; let y = 2; x + y; })()",
-            "(() => { let x = 1, y = 2; x + y; })()",
-        );
+        test("(() => { let x = 1; let y = 2; x + y; })()", "(() => { let x = 1, y = 2; })()");
 
         // do not redeclare function parameters
         // incompatible with strict mode
-        test_same("((x) => { x = 4; let y = 2; x + y; })()");
+        test("((x) => { x = 4; let y = 2; x + y; })()", "((x) => { x = 4; let y = 2; x + 2; })()");
     }
 
     #[test]
diff --git a/crates/oxc_minifier/tests/peephole/esbuild.rs b/crates/oxc_minifier/tests/peephole/esbuild.rs
index ccb3ea873ff16..30fe7d5b0652f 100644
--- a/crates/oxc_minifier/tests/peephole/esbuild.rs
+++ b/crates/oxc_minifier/tests/peephole/esbuild.rs
@@ -561,23 +561,59 @@ fn js_parser_test() {
     test("a = b === c ? true : false", "a = b === c;");
     test("a = b !== c ? true : false", "a = b !== c;");
     test("a ? b(c) : b(d)", "a ? b(c) : b(d);");
-    test("let a; a ? b(c) : b(d)", "let a; a ? b(c) : b(d);");
-    test("let a, b; a ? b(c) : b(d)", "let a, b;b(a ? c : d);");
-    test("let a, b; a ? b(c, 0) : b(d)", "let a, b; a ? b(c, 0) : b(d);");
-    test("let a, b; a ? b(c) : b(d, 0)", "let a, b; a ? b(c) : b(d, 0);");
-    test("let a, b; a ? b(c, 0) : b(d, 1)", "let a, b; a ? b(c, 0) : b(d, 1);");
-    test("let a, b; a ? b(c, 0) : b(d, 0)", "let a, b;b(a ? c : d, 0);");
-    test("let a, b; a ? b(...c) : b(d)", "let a, b; a ? b(...c) : b(d);");
-    test("let a, b; a ? b(c) : b(...d)", "let a, b; a ? b(c) : b(...d);");
-    test("let a, b; a ? b(...c) : b(...d)", "let a, b;b(...a ? c : d);");
-    test("let a, b; a ? b(a) : b(c)", "let a, b;b(a || c);");
-    test("let a, b; a ? b(c) : b(a)", "let a, b;b(a && c);");
-    test("let a, b; a ? b(...a) : b(...c)", "let a, b;b(...a || c);");
-    test("let a, b; a ? b(...c) : b(...a)", "let a, b;b(...a && c);");
-    test("let a; a.x ? b(c) : b(d)", "let a;a.x ? b(c) : b(d);");
-    test("let a, b; a.x ? b(c) : b(d)", "let a, b; a.x ? b(c) : b(d);");
-    test("let a, b; a ? b.y(c) : b.y(d)", "let a, b; a ? b.y(c) : b.y(d);");
-    test("let a, b; a.x ? b.y(c) : b.y(d)", "let a, b; a.x ? b.y(c) : b.y(d);");
+    test("let a = foo(); a ? b(c) : b(d)", "let a = foo(); a ? b(c) : b(d);");
+    test("let a = foo(), b = bar(); a ? b(c) : b(d)", "let a = foo(), b = bar();b(a ? c : d);");
+    test(
+        "let a = foo(), b = bar(); a ? b(c, 0) : b(d)",
+        "let a = foo(), b = bar(); a ? b(c, 0) : b(d);",
+    );
+    test(
+        "let a = foo(), b = bar(); a ? b(c) : b(d, 0)",
+        "let a = foo(), b = bar(); a ? b(c) : b(d, 0);",
+    );
+    test(
+        "let a = foo(), b = bar(); a ? b(c, 0) : b(d, 1)",
+        "let a = foo(), b = bar(); a ? b(c, 0) : b(d, 1);",
+    );
+    test(
+        "let a = foo(), b = bar(); a ? b(c, 0) : b(d, 0)",
+        "let a = foo(), b = bar();b(a ? c : d, 0);",
+    );
+    test(
+        "let a = foo(), b = bar(); a ? b(...c) : b(d)",
+        "let a = foo(), b = bar(); a ? b(...c) : b(d);",
+    );
+    test(
+        "let a = foo(), b = bar(); a ? b(c) : b(...d)",
+        "let a = foo(), b = bar(); a ? b(c) : b(...d);",
+    );
+    test(
+        "let a = foo(), b = bar(); a ? b(...c) : b(...d)",
+        "let a = foo(), b = bar();b(...a ? c : d);",
+    );
+    test("let a = foo(), b = bar(); a ? b(a) : b(c)", "let a = foo(), b = bar();b(a || c);");
+    test("let a = foo(), b = bar(); a ? b(c) : b(a)", "let a = foo(), b = bar();b(a && c);");
+    test(
+        "let a = foo(), b = bar(); a ? b(...a) : b(...c)",
+        "let a = foo(), b = bar();b(...a || c);",
+    );
+    test(
+        "let a = foo(), b = bar(); a ? b(...c) : b(...a)",
+        "let a = foo(), b = bar();b(...a && c);",
+    );
+    test("let a = foo(); a.x ? b(c) : b(d)", "let a = foo(); a.x ? b(c) : b(d);");
+    test(
+        "let a = foo(), b = bar(); a.x ? b(c) : b(d)",
+        "let a = foo(), b = bar(); a.x ? b(c) : b(d);",
+    );
+    test(
+        "let a = foo(), b = bar(); a ? b.y(c) : b.y(d)",
+        "let a = foo(), b = bar(); a ? b.y(c) : b.y(d);",
+    );
+    test(
+        "let a = foo(), b = bar(); a.x ? b.y(c) : b.y(d)",
+        "let a = foo(), b = bar(); a.x ? b.y(c) : b.y(d);",
+    );
     test("a ? b : c ? b : d", "a || c ? b : d;");
     test("a ? b ? c : d : d", "a && b ? c : d;");
     test("a ? c : (b, c)", "a || b, c;");
@@ -592,24 +628,24 @@ fn js_parser_test() {
     test("a ? c : b || c", "a ? c : b || c;");
     test("a = b == null ? c : b", "a = b == null ? c : b;");
     test("a = b != null ? b : c", "a = b == null ? c : b;");
-    test("let b; a = b == null ? c : b", "let b; a = b ?? c;");
-    test("let b; a = b != null ? b : c", "let b; a = b ?? c;");
-    test("let b; a = b == null ? b : c", "let b; a = b == null ? b : c;");
-    test("let b; a = b != null ? c : b", "let b; a = b == null ? b : c;");
-    test("let b; a = null == b ? c : b", "let b; a = b ?? c;");
-    test("let b; a = null != b ? b : c", "let b; a = b ?? c;");
-    test("let b; a = null == b ? b : c", "let b; a = b == null ? b : c;");
-    test("let b; a = null != b ? c : b", "let b; a = b == null ? b : c;");
-    test("let b; a = b.x == null ? c : b.x", "let b; a = b.x == null ? c : b.x;");
-    test("let b; a = b.x != null ? b.x : c", "let b; a = b.x == null ? c : b.x;");
-    test("let b; a = null == b.x ? c : b.x", "let b; a = b.x == null ? c : b.x;");
-    test("let b; a = null != b.x ? b.x : c", "let b; a = b.x == null ? c : b.x;");
-    test("let b; a = b === null ? c : b", "let b; a = b === null ? c : b;");
-    test("let b; a = b !== null ? b : c", "let b; a = b === null ? c : b;");
-    test("let b; a = null === b ? c : b", "let b; a = b === null ? c : b;");
-    test("let b; a = null !== b ? b : c", "let b; a = b === null ? c : b;");
-    test("let b; a = null === b || b === undefined ? c : b", "let b; a = b ?? c;");
-    test("let b; a = b !== undefined && b !== null ? b : c", "let b; a = b ?? c;");
+    test("let b = foo(); a = b == null ? c : b", "let b = foo(); a = b ?? c;");
+    test("let b = foo(); a = b != null ? b : c", "let b = foo(); a = b ?? c;");
+    test("let b = foo(); a = b == null ? b : c", "let b = foo(); a = b == null ? b : c;");
+    test("let b = foo(); a = b != null ? c : b", "let b = foo(); a = b == null ? b : c;");
+    test("let b = foo(); a = null == b ? c : b", "let b = foo(); a = b ?? c;");
+    test("let b = foo(); a = null != b ? b : c", "let b = foo(); a = b ?? c;");
+    test("let b = foo(); a = null == b ? b : c", "let b = foo(); a = b == null ? b : c;");
+    test("let b = foo(); a = null != b ? c : b", "let b = foo(); a = b == null ? b : c;");
+    test("let b = foo(); a = b.x == null ? c : b.x", "let b = foo(); a = b.x == null ? c : b.x;");
+    test("let b = foo(); a = b.x != null ? b.x : c", "let b = foo(); a = b.x == null ? c : b.x;");
+    test("let b = foo(); a = null == b.x ? c : b.x", "let b = foo(); a = b.x == null ? c : b.x;");
+    test("let b = foo(); a = null != b.x ? b.x : c", "let b = foo(); a = b.x == null ? c : b.x;");
+    test("let b = foo(); a = b === null ? c : b", "let b = foo(); a = b === null ? c : b;");
+    test("let b = foo(); a = b !== null ? b : c", "let b = foo(); a = b === null ? c : b;");
+    test("let b = foo(); a = null === b ? c : b", "let b = foo(); a = b === null ? c : b;");
+    test("let b = foo(); a = null !== b ? b : c", "let b = foo(); a = b === null ? c : b;");
+    test("let b = foo(); a = null === b || b === undefined ? c : b", "let b = foo(); a = b ?? c;");
+    test("let b = foo(); a = b !== undefined && b !== null ? b : c", "let b = foo(); a = b ?? c;");
     test("a(b ? 0 : 0)", "a((b, 0));");
     test("a(b ? +0 : -0)", "a(b ? 0 : -0);");
     test("a(b ? +0 : 0)", "a((b, 0));");
@@ -649,8 +685,8 @@ fn js_parser_test() {
     test("if (a) if (b) if (c) d", "a && b && c && d;");
     test("if (!a) if (!b) if (!c) d", "a || b || c || d;");
     test(
-        "function _() { let a, b, c; return a != null ? a : b != null ? b : c }",
-        "function _() { let a, b, c;return a ?? b ?? c; }",
+        "function _() { let a = foo(), b = bar(), c = baz(); return a != null ? a : b != null ? b : c }",
+        "function _() { let a = foo(), b = bar(), c = baz(); return a ?? b ?? c; }",
     );
     test(
         "function _() { if (a) return c; if (b) return d; }",
@@ -789,96 +825,96 @@ fn js_parser_test() {
         "function _() { if (a) { x: if (b) break x;} else return c; }",
     );
     test(
-        "function _() { let a; return a != null ? a.b : undefined }",
-        "function _ () { let a;return a?.b; }",
+        "function _() { let a = foo(); return a != null ? a.b : undefined }",
+        "function _() { let a = foo(); return a?.b; }",
     );
     test(
-        "function _() { let a; return a != null ? a[b] : undefined }",
-        "function _ () { let a;return a?.[b]; }",
+        "function _() { let a = foo(); return a != null ? a[b] : undefined }",
+        "function _() { let a = foo(); return a?.[b]; }",
     );
     test(
-        "function _() { let a; return a != null ? a(b) : undefined }",
-        "function _ () { let a;return a?.(b); }",
+        "function _() { let a = foo(); return a != null ? a(b) : undefined }",
+        "function _() { let a = foo(); return a?.(b); }",
     );
     test(
-        "function _() { let a; return a == null ? undefined : a.b }",
-        "function _ () { let a;return a?.b; }",
+        "function _() { let a = foo(); return a == null ? undefined : a.b }",
+        "function _() { let a = foo(); return a?.b; }",
     );
     test(
-        "function _() { let a; return a == null ? undefined : a[b] }",
-        "function _ () { let a;return a?.[b]; }",
+        "function _() { let a = foo(); return a == null ? undefined : a[b] }",
+        "function _() { let a = foo(); return a?.[b]; }",
     );
     test(
-        "function _() { let a; return a == null ? undefined : a(b) }",
-        "function _ () { let a;return a?.(b); }",
+        "function _() { let a = foo(); return a == null ? undefined : a(b) }",
+        "function _() { let a = foo(); return a?.(b); }",
     );
     test(
-        "function _() { let a; return null != a ? a.b : undefined }",
-        "function _ () { let a;return a?.b; }",
+        "function _() { let a = foo(); return null != a ? a.b : undefined }",
+        "function _() { let a = foo(); return a?.b; }",
     );
     test(
-        "function _() { let a; return null != a ? a[b] : undefined }",
-        "function _ () { let a;return a?.[b]; }",
+        "function _() { let a = foo(); return null != a ? a[b] : undefined }",
+        "function _() { let a = foo(); return a?.[b]; }",
     );
     test(
-        "function _() { let a; return null != a ? a(b) : undefined }",
-        "function _ () { let a;return a?.(b); }",
+        "function _() { let a = foo(); return null != a ? a(b) : undefined }",
+        "function _() { let a = foo(); return a?.(b); }",
     );
     test(
-        "function _() { let a; return null == a ? undefined : a.b }",
-        "function _ () { let a;return a?.b; }",
+        "function _() { let a = foo(); return null == a ? undefined : a.b }",
+        "function _() { let a = foo(); return a?.b; }",
     );
     test(
-        "function _() { let a; return null == a ? undefined : a[b] }",
-        "function _ () { let a;return a?.[b]; }",
+        "function _() { let a = foo(); return null == a ? undefined : a[b] }",
+        "function _() { let a = foo(); return a?.[b]; }",
     );
     test(
-        "function _() { let a; return null == a ? undefined : a(b) }",
-        "function _ () { let a;return a?.(b); }",
+        "function _() { let a = foo(); return null == a ? undefined : a(b) }",
+        "function _() { let a = foo(); return a?.(b); }",
     );
     test(
         "function _() { return a != null ? a.b : undefined }",
-        "function _ () { return a == null ? void 0 : a.b; }",
+        "function _() { return a == null ? void 0 : a.b; }",
     );
     test(
-        "function _() { let a; return a != null ? a.b : null }",
-        "function _ () { let a;return a == null ? null : a.b; }",
+        "function _() { let a = foo(); return a != null ? a.b : null }",
+        "function _() { let a = foo(); return a == null ? null : a.b; }",
     );
     test(
-        "function _() { let a; return a != null ? b.a : undefined }",
-        "function _ () { let a;return a == null ? void 0 : b.a; }",
+        "function _() { let a = foo(); return a != null ? b.a : undefined }",
+        "function _() { let a = foo(); return a == null ? void 0 : b.a; }",
     );
     test(
-        "function _() { let a; return a != 0 ? a.b : undefined }",
-        "function _ () { let a;return a == 0 ? void 0 : a.b; }",
+        "function _() { let a = foo(); return a != 0 ? a.b : undefined }",
+        "function _() { let a = foo(); return a == 0 ? void 0 : a.b; }",
     );
     test(
-        "function _() { let a; return a !== null ? a.b : undefined }",
-        "function _ () { let a;return a === null ? void 0 : a.b; }",
+        "function _() { let a = foo(); return a !== null ? a.b : undefined }",
+        "function _() { let a = foo(); return a === null ? void 0 : a.b; }",
     );
     test(
-        "function _() { let a; return a != undefined ? a.b : undefined }",
-        "function _ () { let a;return a?.b; }",
+        "function _() { let a = foo(); return a != undefined ? a.b : undefined }",
+        "function _() { let a = foo(); return a?.b; }",
     );
     test(
-        "function _() { let a; return a != null ? a?.b : undefined }",
-        "function _ () { let a;return a?.b; }",
+        "function _() { let a = foo(); return a != null ? a?.b : undefined }",
+        "function _() { let a = foo(); return a?.b; }",
     );
     test(
-        "function _() { let a; return a != null ? a.b.c[d](e) : undefined }",
-        "function _ () { let a;return a?.b.c[d](e); }",
+        "function _() { let a = foo(); return a != null ? a.b.c[d](e) : undefined }",
+        "function _() { let a = foo(); return a?.b.c[d](e); }",
     );
     test(
-        "function _() { let a; return a != null ? a?.b.c[d](e) : undefined }",
-        "function _ () { let a;return a?.b.c[d](e); }",
+        "function _() { let a = foo(); return a != null ? a?.b.c[d](e) : undefined }",
+        "function _() { let a = foo(); return a?.b.c[d](e); }",
     );
     test(
-        "function _() { let a; return a != null ? a.b.c?.[d](e) : undefined }",
-        "function _ () { let a;return a?.b.c?.[d](e); }",
+        "function _() { let a = foo(); return a != null ? a.b.c?.[d](e) : undefined }",
+        "function _() { let a = foo(); return a?.b.c?.[d](e); }",
     );
     test(
-        "function _() { let a; return a != null ? a?.b.c?.[d](e) : undefined }",
-        "function _ () { let a;return a?.b.c?.[d](e); }",
+        "function _() { let a = foo(); return a != null ? a?.b.c?.[d](e) : undefined }",
+        "function _() { let a = foo(); return a?.b.c?.[d](e); }",
     );
 }