text: return_undefined: {
      options = {
          booleans: true,
          comparisons: true,
          conditionals: true,
          dead_code: true,
          drop_debugger: true,
          evaluate: true,
          hoist_funs: true,
          hoist_vars: true,
          if_return: true,
          join_vars: true,
          keep_fargs: true,
          keep_fnames: false,
          loops: true,
          negate_iife: true,
          properties: true,
          sequences: false,
          side_effects: true,
          unused: true,
      }
      input: {
          function f0() {
          }
          function f1() {
              return undefined;
          }
          function f2() {
              return void 0;
          }
          function f3() {
              return void 123;
          }
          function f4() {
              return;
          }
          function f5(a, b) {
              console.log(a, b);
              baz(a);
              return;
          }
          function f6(a, b) {
              console.log(a, b);
              if (a) {
                  foo(b);
                  baz(a);
                  return a + b;
              }
              return undefined;
          }
          function f7(a, b) {
              console.log(a, b);
              if (a) {
                  foo(b);
                  baz(a);
                  return void 0;
              }
              return a + b;
          }
          function f8(a, b) {
              foo(a);
              bar(b);
              return void 0;
          }
          function f9(a, b) {
              foo(a);
              bar(b);
              return undefined;
          }
          function f10() {
              return false;
          }
          function f11() {
              return null;
          }
          function f12() {
              return 0;
          }
      }
      expect: {
          function f0() {}
          function f1() {}
          function f2() {}
          function f3() {}
          function f4() {}
          function f5(a, b) {
              console.log(a, b);
              baz(a);
          }
          function f6(a, b) {
              console.log(a, b);
              if (a) {
                  foo(b);
                  baz(a);
                  return a + b;
              }
          }
          function f7(a, b) {
              console.log(a, b);
              if (!a)
                  return a + b;
              foo(b);
              baz(a);
          }
          function f8(a, b) {
              foo(a);
              bar(b);
          }
          function f9(a, b) {
              foo(a);
              bar(b);
          }
          function f10() {
              return !1;
          }
          function f11() {
              return null;
          }
          function f12() {
              return 0;
          }
      }
  }
  
  return_void: {
      options = {
          if_return: true,
          inline: true,
          reduce_vars: true,
          unused: true,
      }
      input: {
          function f() {
              function g() {
                  h();
              }
              return g();
          }
      }
      expect: {
          function f() {
              h();
          }
      }
  }
  