feat(es/minifier): Drop expressions using sequential inliner

crates/swc/tests/tsc-references/ClassAndModuleThatMergeWithStaticFunctionAndNonExportedFunctionThatShareAName.2.minified.js

@@ -25,5 +25,5 @@ Point || (Point = {}), function(A) {
             };
         }, Point;
     }();
-    A.Point = Point, Point = A.Point || (A.Point = {});
+    A.Point = Point, A.Point || (A.Point = {});
 }(A || (A = {}));

crates/swc/tests/tsc-references/assignAnyToEveryType.2.minified.js

@@ -1,6 +1,6 @@
 //// [assignAnyToEveryType.ts]
-var x, E, M;
+var E, M;
 import "@swc/helpers/_/_class_call_check";
 !function(E) {
     E[E.A = 0] = "A";
-}(E || (E = {})), E.A, (M || (M = {})).foo = 1, M = x;
+}(E || (E = {})), E.A, (M || (M = {})).foo = 1;

crates/swc/tests/tsc-references/assignFromBooleanInterface2.2.minified.js

@@ -1,3 +1,3 @@
 //// [assignFromBooleanInterface2.ts]
 var a, b, x = !0;
-a = !0, b = a = b, b = x, x = a, x = b;
+a = !0, b = a = b, b = x, x = a;

crates/swc/tests/tsc-references/assignFromNumberInterface2.2.minified.js

@@ -1,3 +1,3 @@
 //// [assignFromNumberInterface2.ts]
 var a, b, x = 1;
-a = 1, b = a = b, b = x, x = a, x = b;
+a = 1, b = a = b, b = x, x = a;

crates/swc/tests/tsc-references/assignFromStringInterface2.2.minified.js

@@ -1,3 +1,3 @@
 //// [assignFromStringInterface2.ts]
 var a, b, x = "";
-a = x, b = a = b, b = x, x = a, x = b;
+a = x, b = a = b, b = x, x = a;

crates/swc/tests/tsc-references/assignmentCompatWithCallSignatures6.2.minified.js

@@ -3,4 +3,4 @@ var x, b, b2, b3, b4, b5, b11, b16;
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
 import { _ as _create_super } from "@swc/helpers/_/_create_super";
-x.a = b, b = x.a, x.a2 = b2, b2 = x.a2, x.a3 = b3, b3 = x.a3, x.a4 = b4, b4 = x.a4, x.a5 = b5, b5 = x.a5, x.a11 = b11, b11 = x.a11, x.a16 = b16, b16 = x.a16;
+x.a = b, b = x.a, x.a2 = b2, b2 = x.a2, x.a3 = b3, b3 = x.a3, x.a4 = b4, b4 = x.a4, x.a5 = b5, b5 = x.a5, x.a11 = b11, b11 = x.a11, x.a16 = b16, x.a16;

crates/swc/tests/tsc-references/assignmentCompatWithConstructSignatures6.2.minified.js

@@ -3,4 +3,4 @@ var x, b, b2, b3, b4, b5, b11, b16;
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
 import { _ as _create_super } from "@swc/helpers/_/_create_super";
-x.a = b, b = x.a, x.a2 = b2, b2 = x.a2, x.a3 = b3, b3 = x.a3, x.a4 = b4, b4 = x.a4, x.a5 = b5, b5 = x.a5, x.a11 = b11, b11 = x.a11, x.a16 = b16, b16 = x.a16;
+x.a = b, b = x.a, x.a2 = b2, b2 = x.a2, x.a3 = b3, b3 = x.a3, x.a4 = b4, b4 = x.a4, x.a5 = b5, b5 = x.a5, x.a11 = b11, b11 = x.a11, x.a16 = b16, x.a16;

crates/swc/tests/tsc-references/assignmentCompatWithDiscriminatedUnion.2.minified.js

@@ -1,12 +1,6 @@
 //// [assignmentCompatWithDiscriminatedUnion.ts]
 var Example1, Example2, Example3, Example4, Example5, GH14865, GH30170, GH12052, GH18421, GH15907, GH20889, GH39357;
-Example1 || (Example1 = {}), t = s, Example2 || (Example2 = {}), t = s, Example3 || (Example3 = {}), t = s, Example4 || (Example4 = {}), t = s, Example5 || (Example5 = {}), t = s, function(GH14865) {
-    var b1, a = {
-        type: "A",
-        data: "whatevs"
-    };
-    a.type, b1.type, b1 = a;
-}(GH14865 || (GH14865 = {})), GH30170 || (GH30170 = {}), function(GH12052) {
+Example1 || (Example1 = {}), t = s, Example2 || (Example2 = {}), t = s, Example3 || (Example3 = {}), t = s, Example4 || (Example4 = {}), t = s, Example5 || (Example5 = {}), t = s, GH14865 || (GH14865 = {}), (void 0).type, GH30170 || (GH30170 = {}), function(GH12052) {
     var getAxisType = function() {
         return "categorical";
     };

crates/swc/tests/tsc-references/assignmentCompatWithObjectMembers.2.minified.js

@@ -2,10 +2,10 @@
 var SimpleTypes, ObjectTypes;
 import "@swc/helpers/_/_class_call_check";
 SimpleTypes || (SimpleTypes = {}), function(ObjectTypes) {
-    var t, t2, b, a2 = {
+    var t2, b, a2 = {
         foo: a2
     }, b2 = {
         foo: b2
     };
-    b2 = a2 = b2, a2 = b, a2 = t2, a2 = t;
+    b2 = a2 = b2, a2 = b, a2 = t2;
 }(ObjectTypes || (ObjectTypes = {}));

crates/swc/tests/tsc-references/assignmentCompatWithObjectMembersOptionality.2.minified.js

@@ -6,10 +6,4 @@ var TargetHasOptional, SourceHasOptional, Base = function Base() {
     "use strict";
     _class_call_check(this, Base);
 };
-!function(TargetHasOptional) {
-    var c, a, d, e, f;
-    new Base(), c = d, c = e, c = f, c = a, a = d, a = e, a = f, a = c;
-}(TargetHasOptional || (TargetHasOptional = {})), function(SourceHasOptional) {
-    var c, a, d, e, f;
-    new Base(), c = d, c = e, c = f, c = a, a = d, a = e, a = f, a = c;
-}(SourceHasOptional || (SourceHasOptional = {}));
+TargetHasOptional || (TargetHasOptional = {}), new Base(), SourceHasOptional || (SourceHasOptional = {}), new Base();

crates/swc/tests/tsc-references/assignmentCompatWithObjectMembersOptionality2.2.minified.js

@@ -6,7 +6,4 @@ var TargetHasOptional, SourceHasOptional, Base = function Base() {
     "use strict";
     _class_call_check(this, Base);
 };
-TargetHasOptional || (TargetHasOptional = {}), new Base(), function(SourceHasOptional) {
-    var c, a, d, e, f;
-    new Base(), c = d, c = e, c = f, c = a, a = d, a = e, a = f, a = c;
-}(SourceHasOptional || (SourceHasOptional = {}));
+TargetHasOptional || (TargetHasOptional = {}), new Base(), SourceHasOptional || (SourceHasOptional = {}), new Base();

crates/swc/tests/tsc-references/assignmentToParenthesizedIdentifiers.2.minified.js

@@ -25,4 +25,4 @@ import "@swc/helpers/_/_class_call_check";
     x: ""
 }, function(E) {
     E[E.A = 0] = "A";
-}(E || (E = {})), E = void 0, E = void 0;
+}(E || (E = {}));

crates/swc/tests/tsc-references/emitCompoundExponentiationOperator1.2.minified.js

@@ -1,3 +1 @@
 //// [emitCompoundExponentiationOperator1.ts]
-var comp;
-comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp, 1), Math.pow(comp, comp)), Math.pow(comp, Math.pow(comp, 2))), Math.pow(comp, comp) + 2), Math.pow(comp, comp) - 2), 2 * Math.pow(comp, comp)), Math.pow(comp, comp) / 2), Math.pow(comp, comp) % 2), Math.pow(comp - 2, 5)), Math.pow(comp + 2, 5)), Math.pow(2 * comp, 5)), Math.pow(comp / 2, 5)), Math.pow(comp % 2, 5)), Math.pow(comp, 7)), Math.pow(comp, 3)), Math.pow(comp, 10)), Math.pow(comp, 2.5)), Math.pow(comp, 1));

crates/swc/tests/tsc-references/emitCompoundExponentiationOperator2.2.minified.js

@@ -1,3 +1 @@
 //// [emitCompoundExponentiationOperator2.ts]
-var comp;
-comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp = Math.pow(comp, 1), comp = Math.pow(comp, 1)), comp = Math.pow(comp, 3)), comp = Math.pow(comp, -1)), comp = Math.pow(comp, 2)), comp = Math.pow(comp, 0.5)), comp = Math.pow(comp, 3)), comp = Math.pow(comp, -1)), comp = Math.pow(comp, 2)), comp = Math.pow(comp, 0.5)), comp = Math.pow(comp, 9)), comp = Math.pow(comp, -15)), comp = Math.pow(comp, 32)), comp = Math.pow(comp, 0.015625)), comp = Math.pow(comp, 27)), comp = Math.pow(comp, 1)), comp = Math.pow(comp, 32)), comp = Math.pow(comp, 0.015625));

crates/swc/tests/tsc-references/intersectionAndUnionTypes.2.minified.js

@@ -1,3 +1,3 @@
 //// [intersectionAndUnionTypes.ts]
 var a, b, anb, aob, cnd, cod, x, y;
-a = anb, b = anb, anb = a, x = anb = b, x = aob, x = cnd, anb = x = cod, aob = x, cnd = x, cod = x, y = anb, y = aob, y = cnd, anb = y = cod, aob = y, cnd = y, cod = y;
+a = anb, b = anb, anb = a, x = anb = b, x = aob, x = cnd, anb = x = cod, aob = x, cnd = x, cod = x, y = anb, y = aob, y = cnd, anb = y = cod, aob = y, cnd = y;

crates/swc/tests/tsc-references/intersectionTypeAssignment.2.minified.js

@@ -1,3 +1,3 @@
 //// [intersectionTypeAssignment.ts]
-var a, b, x, y;
-a = x, x = a = y, y = a, b = x, x = b = y, y = x = y = b;
+var a, x, y;
+a = x, x = a = y, x = y = a;

crates/swc/tests/tsc-references/invalidBooleanAssignments.2.minified.js

@@ -3,4 +3,4 @@ var E, M;
 import "@swc/helpers/_/_class_call_check";
 !function(E) {
     E[E.A = 0] = "A";
-}(E || (E = {})), (M || (M = {})).a = 1, M = !0;
+}(E || (E = {})), (M || (M = {})).a = 1;

crates/swc/tests/tsc-references/invalidNumberAssignments.2.minified.js

@@ -1,4 +1,4 @@
 //// [invalidNumberAssignments.ts]
 var M;
 import "@swc/helpers/_/_class_call_check";
-(M || (M = {})).x = 1, M = 1;
+(M || (M = {})).x = 1;

crates/swc/tests/tsc-references/invalidUndefinedAssignments.2.minified.js

@@ -3,4 +3,4 @@ var x, E, M;
 import "@swc/helpers/_/_class_call_check";
 !function(E) {
     E[E.A = 0] = "A";
-}(E || (E = {})), (E = x).A = x, I = x, (M || (M = {})).x = 1, M = x;
+}(E || (E = {})), (E = x).A = x, I = x, (M || (M = {})).x = 1;

crates/swc/tests/tsc-references/invalidVoidAssignments.2.minified.js

@@ -3,6 +3,4 @@ var x, M, E;
 import "@swc/helpers/_/_class_call_check";
 (M || (M = {})).x = 1, M = x, function(E) {
     E[E.A = 0] = "A";
-}(E || (E = {})), x = E, x = E.A, x = {
-    f: function() {}
-};
+}(E || (E = {})), x = E, x = E.A;

crates/swc/tests/tsc-references/literalTypes2.2.minified.js

@@ -14,11 +14,8 @@ g1(1), g2(1, 1), g2(1, 2), g3(1, "two"), g4(1), g5(1, 2), g6([
     return x;
 }), g8(1, function(x) {
     return x + 1;
-});
-var aa = [
+}), function(a, x) {
+    a.slice().push(1);
+}([
     0
-];
-aa = function(a, x) {
-    var result = a.slice();
-    return result.push(1), result;
-}(aa, 0);
+], 0);

crates/swc/tests/tsc-references/nonPrimitiveAssignError.2.minified.js

@@ -4,4 +4,4 @@ var a, x = {}, y = {
 };
 x = a, y = a, a = x, a = y;
 var s = "fooo";
-a = 123, a = !0, s = a = s, a = 123, a = !0, a = "string";
+a = 123, a = !0, s = a = s;

crates/swc/tests/tsc-references/recursiveIntersectionTypes.2.minified.js

@@ -1,3 +1,3 @@
 //// [recursiveIntersectionTypes.ts]
-var entityList, productList;
-entityList.name, entityList.next.name, entityList.next.next.name, entityList.next.next.next.name, productList = entityList = productList;
+var entityList;
+entityList.name, entityList.next.name, entityList.next.next.name, entityList.next.next.next.name;

crates/swc/tests/tsc-references/strictTupleLength.2.minified.js

@@ -1,4 +1,3 @@
 //// [strictTupleLength.ts]
 t0.length, t1.length, t2.length, arr.length;
 var t0, t2, arr, t1 = t2, t2 = t1;
-arr = t1 = arr;

crates/swc/tests/tsc-references/stringLiteralTypeAssertion01.2.minified.js

@@ -1,3 +1,3 @@
 //// [stringLiteralTypeAssertion01.ts]
 var s, t, str;
-s = t, s = t, s = str, t = s = str, t = s, t = str, t = str, str = s, str = s, str = t, str = t;
+s = t, s = t, s = str, t = s = str, t = s, t = str, t = str, str = s, str = s, str = t;

crates/swc/tests/tsc-references/typeArgumentsWithStringLiteralTypes01.2.minified.js

@@ -12,11 +12,11 @@ function fun3() {
 }
 !function(n1) {
     var a = n1.a = fun1("Hello", "World"), b = n1.b = fun1("Hello", "Hello"), c = n1.c = fun2("Hello", "World"), d = n1.d = fun2("Hello", "Hello"), e = n1.e = fun3("Hello", "Hello", "World", "Foo");
-    a = takeReturnString(a), b = takeReturnString(b), c = takeReturnString(c), d = takeReturnString(d), e = takeReturnString(e), a = takeReturnHello(a), b = takeReturnHello(b), c = takeReturnHello(c), d = takeReturnHello(d), e = takeReturnHello(e), a = takeReturnHelloWorld(a), b = takeReturnHelloWorld(b), c = takeReturnHelloWorld(c), d = takeReturnHelloWorld(d), e = takeReturnHelloWorld(e);
+    a = takeReturnString(a), b = takeReturnString(b), c = takeReturnString(c), d = takeReturnString(d), e = takeReturnString(e), a = takeReturnHello(a), b = takeReturnHello(b), c = takeReturnHello(c), d = takeReturnHello(d), e = takeReturnHello(e), a = takeReturnHelloWorld(a), b = takeReturnHelloWorld(b), c = takeReturnHelloWorld(c), d = takeReturnHelloWorld(d), takeReturnHelloWorld(e);
 }(n1 || (n1 = {})), function(n2) {
     var a = n2.a = fun1("Hello", "Hello"), b = n2.b = fun1("Hello", "World"), c = n2.c = fun2("Hello", "Hello"), d = n2.d = fun2("Hello", "World"), e = n2.e = fun3("Hello", "World");
-    a = takeReturnString(a), b = takeReturnString(b), c = takeReturnString(c), d = takeReturnString(d), e = takeReturnString(e), a = takeReturnHello(a), b = takeReturnHello(b), c = takeReturnHello(c), d = takeReturnHello(d), e = takeReturnHello(e), a = takeReturnHelloWorld(a), b = takeReturnHelloWorld(b), c = takeReturnHelloWorld(c), d = takeReturnHelloWorld(d), e = takeReturnHelloWorld(e);
+    a = takeReturnString(a), b = takeReturnString(b), c = takeReturnString(c), d = takeReturnString(d), e = takeReturnString(e), a = takeReturnHello(a), b = takeReturnHello(b), c = takeReturnHello(c), d = takeReturnHello(d), e = takeReturnHello(e), a = takeReturnHelloWorld(a), b = takeReturnHelloWorld(b), c = takeReturnHelloWorld(c), d = takeReturnHelloWorld(d), takeReturnHelloWorld(e);
 }(n2 || (n2 = {})), function(n3) {
     var a = n3.a = fun2("Hello", "World"), b = n3.b = fun2("World", "Hello"), c = n3.c = fun2("Hello", "Hello"), d = n3.d = fun2("World", "World"), e = n3.e = fun3("Hello", "World");
-    a = takeReturnString(a), b = takeReturnString(b), c = takeReturnString(c), d = takeReturnString(d), e = takeReturnString(e), a = takeReturnHello(a), b = takeReturnHello(b), c = takeReturnHello(c), d = takeReturnHello(d), e = takeReturnHello(e), a = takeReturnHelloWorld(a), b = takeReturnHelloWorld(b), c = takeReturnHelloWorld(c), d = takeReturnHelloWorld(d), e = takeReturnHelloWorld(e);
+    a = takeReturnString(a), b = takeReturnString(b), c = takeReturnString(c), d = takeReturnString(d), e = takeReturnString(e), a = takeReturnHello(a), b = takeReturnHello(b), c = takeReturnHello(c), d = takeReturnHello(d), e = takeReturnHello(e), a = takeReturnHelloWorld(a), b = takeReturnHelloWorld(b), c = takeReturnHelloWorld(c), d = takeReturnHelloWorld(d), takeReturnHelloWorld(e);
 }(n3 || (n3 = {}));

crates/swc/tests/tsc-references/typeGuardsInFunction.2.minified.js

@@ -1,3 +1 @@
 //// [typeGuardsInFunction.ts]
-var strOrNum;
-strOrNum = "string" == typeof strOrNum && strOrNum;

crates/swc/tests/tsc-references/unionTypesAssignability.2.minified.js

@@ -1,6 +1,6 @@
 //// [unionTypesAssignability.ts]
-var unionNumberString, unionDE, num, str, c, d, e, anyVar;
+var unionNumberString, unionDE, num, str, c, d, e;
 import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
 import { _ as _inherits } from "@swc/helpers/_/_inherits";
 import { _ as _create_super } from "@swc/helpers/_/_create_super";
-c = d, c = e, c = unionDE, d = e, e = d = unionDE, e = unionDE, num = str, str = num = unionNumberString, str = unionNumberString, d = c, e = c, unionDE = c, e = d, unionDE = d, d = e, unionDE = e, str = num, unionNumberString = num, num = str, unionNumberString = str, anyVar = unionDE, unionDE = anyVar = unionNumberString, unionNumberString = anyVar, unionDE = null, unionNumberString = null, unionDE = void 0, unionNumberString = void 0;
+c = d, c = e, c = unionDE, d = e, e = d = unionDE, e = unionDE, num = str, str = num = unionNumberString, str = unionNumberString, d = c, e = c, unionDE = c, e = d, unionDE = d, d = e, unionDE = e, str = num, unionNumberString = num, num = str;

crates/swc/tests/tsc-references/validEnumAssignments.2.minified.js

@@ -1,5 +1,5 @@
 //// [validEnumAssignments.ts]
-var E, n, e;
+var E;
 !function(E) {
     E[E.A = 0] = "A", E[E.B = 1] = "B";
-}(E || (E = {})), n = e, n = E.A, E.A, e = E.A, e = E.B, e = n, e = null, e = void 0, e = 1, e = 1., e = 1.0, e = -1;
+}(E || (E = {})), E.A, E.A, E.A, E.B;

crates/swc/tests/tsc-references/validNullAssignments.2.minified.js

@@ -3,4 +3,4 @@ var E, M;
 import "@swc/helpers/_/_class_call_check";
 !function(E) {
     E[E.A = 0] = "A";
-}(E || (E = {})), E.A = null, I = null, (M || (M = {})).x = 1, M = null;
+}(E || (E = {})), E.A = null, I = null, (M || (M = {})).x = 1;

crates/swc_ecma_minifier/src/compress/optimize/dead_code.rs

@@ -33,18 +33,21 @@ where
     ///     throw x();
     /// }
     /// ```
-    pub(super) fn optimize_in_fn_termination(&mut self, e: &mut Expr) {
+    /// # Returns
+    ///
+    /// returns true if `e` is changed.
+    pub(super) fn optimize_last_expr_before_termination(&mut self, e: &mut Expr) -> bool {
         if !self.options.dead_code {
-            return;
+            return false;
         }
 
         // A return statement in a try block may not terminate function.
         if self.ctx.in_try_block {
-            return;
+            return false;
         }
 
         if let Expr::Assign(assign @ AssignExpr { op: op!("="), .. }) = e {
-            self.optimize_in_fn_termination(&mut assign.right);
+            self.optimize_last_expr_before_termination(&mut assign.right);
 
             // We only handle identifiers on lhs for now.
             if let Some(lhs) = assign.left.as_ident() {
@@ -53,7 +56,7 @@ where
                     .data
                     .vars
                     .get(&lhs.to_id())
-                    .map(|var| var.is_fn_local && !var.declared_as_fn_param)
+                    .map(|var| var.declared && var.is_fn_local && !var.declared_as_fn_param)
                     .unwrap_or(false)
                 {
                     report_change!(
@@ -62,7 +65,7 @@ where
                     );
                     self.changed = true;
                     *e = *assign.right.take();
-                    return;
+                    return true;
                 }
             }
         }
@@ -76,7 +79,7 @@ where
                         .data
                         .vars
                         .get(&lhs.to_id())
-                        .map(|var| var.is_fn_local)
+                        .map(|var| var.declared && var.is_fn_local)
                         .unwrap_or(false)
                     {
                         report_change!(
@@ -91,9 +94,12 @@ where
                             left: Box::new(Expr::Ident(lhs.clone())),
                             right: assign.right.take(),
                         });
+                        return true;
                     }
                 }
             }
         }
+
+        false
     }
 }