Fix interop between class and static decorators

packages/babel-plugin-proposal-decorators/src/transformer-2021-12.ts

@@ -479,7 +479,7 @@ function transformClass(
       continue;
     }
 
-    if (element.node.decorators) {
+    if (element.node.decorators && element.node.decorators.length > 0) {
       hasElementDecorators = true;
     } else if (element.node.type === "ClassAccessorProperty") {
       const { key, value, static: isStatic } = element.node;
@@ -572,7 +572,7 @@ function transformClass(
         hasComputedProps = true;
       }
 
-      if (Array.isArray(decorators)) {
+      if (Array.isArray(decorators) && decorators.length > 0) {
         let locals: t.Identifier | t.Identifier[];
         let privateMethods: t.FunctionExpression | t.FunctionExpression[];
 

packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc/all-decorators/input.js

@@ -0,0 +1,26 @@
+@dec
+class Class {
+  @dec a;
+  @dec b() {}
+  @dec get c() {}
+  @dec set c(v) {}
+  @dec accessor d;
+
+  @dec #e;
+  @dec #f() {}
+  @dec get #g() {}
+  @dec set #g(v) {}
+  @dec accessor #h;
+
+  @dec static i;
+  @dec static j() {}
+  @dec static get k() {}
+  @dec static set l(v) {}
+  @dec static accessor m;
+
+  @dec static #n;
+  @dec static #o() {}
+  @dec static get #p() {}
+  @dec static set #q(v) {}
+  @dec static accessor #r;
+}

packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc/all-decorators/output.js

@@ -0,0 +1,113 @@
+var _initClass, _init_a, _init_d, _init_e, _call_f, _call_g, _call_g2, _init_h, _get_h, _set_h, _init_i, _init_m, _init_n, _call_o, _call_p, _call_q, _init_r, _get_r, _set_r, _initProto, _initStatic;
+
+let _Class;
+
+new class extends babelHelpers.identity {
+  static {
+    class Class {
+      static {
+        [_init_a, _init_d, _init_e, _call_f, _call_g, _call_g2, _init_h, _get_h, _set_h, _init_i, _init_m, _init_n, _call_o, _call_p, _call_q, _init_r, _get_r, _set_r, _Class, _initClass, _initProto, _initStatic] = babelHelpers.applyDecs(this, [[dec, 0, "a"], [dec, 2, "b"], [dec, 3, "c"], [dec, 4, "c"], [dec, 1, "d"], [dec, 0, "e", function () {
+          return this.#e;
+        }, function (value) {
+          this.#e = value;
+        }], [dec, 2, "f", function () {}], [dec, 3, "g", function () {}], [dec, 4, "g", function (v) {}], [dec, 1, "h", function () {
+          return this.#B;
+        }, function (value) {
+          this.#B = value;
+        }], [dec, 5, "i"], [dec, 7, "j"], [dec, 8, "k"], [dec, 9, "l"], [dec, 6, "m"], [dec, 5, "n", function () {
+          return this.#n;
+        }, function (value) {
+          this.#n = value;
+        }], [dec, 7, "o", function () {}], [dec, 8, "p", function () {}], [dec, 9, "q", function (v) {}], [dec, 6, "r", function () {
+          return this.#D;
+        }, function (value) {
+          this.#D = value;
+        }]], [dec]);
+
+        _initStatic(this);
+
+      }
+      #f = _call_f;
+      a = (_initProto(this), _init_a(this));
+
+      b() {}
+
+      get c() {}
+
+      set c(v) {}
+
+      #A = _init_d(this);
+
+      get d() {
+        return this.#A;
+      }
+
+      set d(v) {
+        this.#A = v;
+      }
+
+      #e = _init_e(this);
+
+      get #g() {
+        return _call_g(this);
+      }
+
+      set #g(v) {
+        _call_g2(this, v);
+      }
+
+      #B = _init_h(this);
+
+      set #h(v) {
+        _set_h(this, v);
+      }
+
+      get #h() {
+        _get_h(this);
+      }
+
+      static j() {}
+
+      static get k() {}
+
+      static set l(v) {}
+
+      static get m() {
+        return this.#C;
+      }
+
+      static set m(v) {
+        this.#C = v;
+      }
+
+      set #r(v) {
+        _set_r(this, v);
+      }
+
+      get #r() {
+        _get_r(this);
+      }
+
+    }
+
+  }
+  #o = _call_o;
+  i = _init_i(this);
+  #C = _init_m(this);
+  #n = _init_n(this);
+
+  get #p() {
+    return _call_p(this);
+  }
+
+  set #q(v) {
+    _call_q(this, v);
+  }
+
+  #D = _init_r(this);
+
+  constructor() {
+    super(_Class), _initClass();
+  }
+
+}();