text: iife_for: {
      options = {
          negate_iife: true,
          reduce_vars: true,
          toplevel: true,
          unused: true,
      }
      input: {
          function f() {
              function g() {
                  L: for (;;) break L;
              }
              g();
          }
          f();
      }
      expect: {
          !function() {
              !function() {
                  L: for (;;) break L;
              }();
          }();
      }
  }
  
  iife_for_in: {
      options = {
          negate_iife: true,
          reduce_vars: true,
          toplevel: true,
          unused: true,
      }
      input: {
          function f() {
              function g() {
                  L: for (var a in x) break L;
              }
              g();
          }
          f();
      }
      expect: {
          !function() {
              !function() {
                  L: for (var a in x) break L;
              }();
          }();
      }
  }
  
  iife_do: {
      options = {
          negate_iife: true,
          reduce_vars: true,
          toplevel: true,
          unused: true,
      }
      input: {
          function f() {
              function g() {
                  L: do {
                      break L;
                  } while (1);
              }
              g();
          }
          f();
      }
      expect: {
          !function() {
              !function() {
                  L: do {
                      break L;
                  } while (1);
              }();
          }();
      }
  }
  
  iife_while: {
      options = {
          negate_iife: true,
          reduce_vars: true,
          toplevel: true,
          unused: true,
      }
      input: {
          function f() {
              function g() {
                  L: while (1) break L;
              }
              g();
          }
          f();
      }
      expect: {
          !function() {
              !function() {
                  L: while (1) break L;
              }();
          }();
      }
  }
  
  label_do: {
      options = {
          evaluate: true,
          loops: true,
      }
      input: {
          L: do {
              continue L;
          } while (0);
      }
      expect: {
          L: do {
              continue L;
          } while (0);
      }
  }
  
  label_while: {
      options = {
          evaluate: true,
          dead_code: true,
          loops: true,
      }
      input: {
          function f() {
              L: while (0) continue L;
          }
      }
      expect_exact: "function f(){L:;}"
  }
  