class extends expression not transpiled

[ClassicOldSong]

Reproduce

On output line 12, it keeps the {ccc} unchanged, which should be {ccc: ccc}.

This should be considered as a serious bug.

[kzc]

I'm surprised this wasn't noticed before.

A more accurate issue title would be "class extends expression not transpiled".

Here's a likely fix:

--- a/src/program/types/ClassDeclaration.js
+++ b/src/program/types/ClassDeclaration.js
@@ -40,6 +40,7 @@ export default class ClassDeclaration extends Node {
                        }
 
                        if (this.superClass) {
+                               this.superClass.transpile(code, transforms);
                                if (this.superClass.end === this.body.start) {
                                        code.remove(c, this.superClass.start);
                                        code.appendLeft(c, ` = /*@__PURE__*/(function (${superName}) {\n${i1}`);
diff --git a/src/program/types/ClassExpression.js b/src/program/types/ClassExpression.js
index 911003a..ded0bb3 100644
--- a/src/program/types/ClassExpression.js
+++ b/src/program/types/ClassExpression.js
@@ -28,6 +28,7 @@ export default class ClassExpression extends Node {
                        const i1 = i0 + code.getIndentString();
 
                        if (this.superClass) {
+                               this.superClass.transpile(code, transforms);
                                code.remove(this.start, this.superClass.start);
                                code.remove(this.superClass.end, this.body.start);
                                code.appendRight(this.start, `/*@__PURE__*/(function (${superName}) {\n${i1}`);

Without patch:

$ echo 'class A extends class B extends class C{c(){}}{b(){}}{a(){}}' | buble
var A = /*@__PURE__*/(function (B) {
	function A () {
		B.apply(this, arguments);
	}

	if ( B ) A.__proto__ = B;
	A.prototype = Object.create( B && B.prototype );
	A.prototype.constructor = A;

	A.prototype.a = function a (){};

	return A;
}(class B extends class C{c(){}}{b(){}}));

With patch:

$ echo 'class A extends class B extends class C{c(){}}{b(){}}{a(){}}' | bin/buble
var A = /*@__PURE__*/(function (B) {
	function A () {
		B.apply(this, arguments);
	}

	if ( B ) A.__proto__ = B;
	A.prototype = Object.create( B && B.prototype );
	A.prototype.constructor = A;

	A.prototype.a = function a (){};

	return A;
}(/*@__PURE__*/(function (C) {
	function B () {
		C.apply(this, arguments);
	}

	if ( C ) B.__proto__ = C;
	B.prototype = Object.create( C && C.prototype );
	B.prototype.constructor = B;

	B.prototype.b = function b (){};

	return B;
}(/*@__PURE__*/(function () {
	function C () {}

	C.prototype.c = function c (){};

	return C;
}())))));

Please submit a PR with this test exercising extends transpilation of class declaration and class expression.

Here's an example of a test: 5195f3f