node fixes, updates

7 files changed, 1874 insertions, 0 deletions

diff --git a/node_modules/babel-plugin-minify-simplify/lib/assignment-expression.js b/node_modules/babel-plugin-minify-simplify/lib/assignment-expression.js
new file mode 100644
index 00000000..3f9b0ce4
--- /dev/null
+++ b/node_modules/babel-plugin-minify-simplify/lib/assignment-expression.js
@@ -0,0 +1,96 @@
+"use strict";
+
+const operators = new Set(["+", "-", "*", "%", "<<", ">>", ">>>", "&", "|", "^", "/", "**"]);
+const updateOperators = new Set(["+", "-"]);
+
+module.exports = t => {
+  function simplify(path) {
+    const rightExpr = path.get("right");
+    const leftExpr = path.get("left");
+
+    if (path.node.operator !== "=") {
+      return;
+    }
+
+    const canBeUpdateExpression = rightExpr.get("right").isNumericLiteral() && rightExpr.get("right").node.value === 1 && updateOperators.has(rightExpr.node.operator);
+
+    if (leftExpr.isMemberExpression()) {
+      const leftPropNames = getPropNames(leftExpr);
+      const rightPropNames = getPropNames(rightExpr.get("left"));
+
+      if (!leftPropNames || leftPropNames.indexOf(undefined) > -1 || !rightPropNames || rightPropNames.indexOf(undefined) > -1 || !operators.has(rightExpr.node.operator) || !areArraysEqual(leftPropNames, rightPropNames)) {
+        return;
+      }
+    } else {
+      if (!rightExpr.isBinaryExpression() || !operators.has(rightExpr.node.operator) || leftExpr.node.name !== rightExpr.node.left.name) {
+        return;
+      }
+    }
+
+    let newExpression; // special case x=x+1 --> ++x
+
+    if (canBeUpdateExpression) {
+      newExpression = t.updateExpression(rightExpr.node.operator + rightExpr.node.operator, t.clone(leftExpr.node), true
+      /* prefix */
+      );
+    } else {
+      newExpression = t.assignmentExpression(rightExpr.node.operator + "=", t.clone(leftExpr.node), t.clone(rightExpr.node.right));
+    }
+
+    path.replaceWith(newExpression);
+  }
+
+  return {
+    simplify
+  };
+};
+
+function areArraysEqual(arr1, arr2) {
+  return arr1.every((value, index) => {
+    return String(value) === String(arr2[index]);
+  });
+}
+
+function getPropNames(path) {
+  if (!path.isMemberExpression()) {
+    return;
+  }
+
+  let obj = path.get("object");
+  const prop = path.get("property");
+  const propNames = [getName(prop.node)];
+
+  while (obj.type === "MemberExpression") {
+    const node = obj.get("property").node;
+
+    if (node) {
+      propNames.push(getName(node));
+    }
+
+    obj = obj.get("object");
+  }
+
+  propNames.push(getName(obj.node));
+  return propNames;
+}
+
+function getName(node) {
+  if (node.type === "ThisExpression") {
+    return "this";
+  }
+
+  if (node.type === "Super") {
+    return "super";
+  }
+
+  if (node.type === "NullLiteral") {
+    return "null";
+  } // augment identifiers so that they don't match
+  // string/number literals
+  // but still match against each other
+
+
+  return node.name ? node.name + "_" : node.value
+  /* Literal */
+  ;
+}
\ No newline at end of file
diff --git a/node_modules/babel-plugin-minify-simplify/lib/conditional-expression.js b/node_modules/babel-plugin-minify-simplify/lib/conditional-expression.js
new file mode 100644
index 00000000..9640e8c8
--- /dev/null
+++ b/node_modules/babel-plugin-minify-simplify/lib/conditional-expression.js
@@ -0,0 +1,39 @@
+"use strict";
+
+const h = require("./helpers");
+
+const PatternMatch = require("./pattern-match");
+
+module.exports = t => {
+  // small abstractions
+  const not = node => t.unaryExpression("!", node);
+
+  const notnot = node => not(not(node));
+
+  const or = (a, b) => t.logicalExpression("||", a, b);
+
+  const and = (a, b) => t.logicalExpression("&&", a, b);
+
+  function simplifyPatterns(path) {
+    const test = path.get("test");
+    const consequent = path.get("consequent");
+    const alternate = path.get("alternate");
+
+    const _h$typeSymbols = h.typeSymbols(t),
+          EX = _h$typeSymbols.Expression; // Convention:
+    // ===============
+    // for each pattern [test, consequent, alternate, handler(expr, cons, alt)]
+
+
+    const matcher = new PatternMatch([[EX, true, false, e => notnot(e)], [EX, false, true, e => not(e)], [EX, true, EX, (e, c, a) => or(notnot(e), a)], [EX, false, EX, (e, c, a) => and(not(e), a)], [EX, EX, true, (e, c) => or(not(e), c)], [EX, EX, false, (e, c) => and(notnot(e), c)]]);
+    const result = matcher.match([test, consequent, alternate], h.isPatternMatchesPath(t));
+
+    if (result.match) {
+      path.replaceWith(result.value(test.node, consequent.node, alternate.node));
+    }
+  }
+
+  return {
+    simplifyPatterns
+  };
+};
\ No newline at end of file
diff --git a/node_modules/babel-plugin-minify-simplify/lib/helpers.js b/node_modules/babel-plugin-minify-simplify/lib/helpers.js
new file mode 100644
index 00000000..dfbe7c2a
--- /dev/null
+++ b/node_modules/babel-plugin-minify-simplify/lib/helpers.js
@@ -0,0 +1,56 @@
+"use strict";
+
+const VOID_0 = t => t.unaryExpression("void", t.numericLiteral(0), true);
+
+const evaluate = require("babel-helper-evaluate-path"); // Types as Symbols - for comparing types
+
+
+const types = {}; // This is a test key which is used to avoid Object.keys check
+// Object.keys() check is really expensive
+// https://gist.github.com/vigneshshanmugam/c766550ecd02292dcdfbf0bf013b9d3d
+
+const testKey = "Expression";
+
+const typeSymbols = t => {
+  // don't recompute
+  if (types[testKey] !== undefined) {
+    return types;
+  }
+
+  t.TYPES.forEach(type => {
+    types[type] = Symbol.for(type);
+  });
+  return types;
+};
+
+const isNodeOfType = (t, node, typeSymbol) => typeof typeSymbol !== "symbol" ? false : t["is" + Symbol.keyFor(typeSymbol)](node);
+
+const isPatternMatchesPath = t => function _isPatternMatchesPath(patternValue, inputPath) {
+  if (Array.isArray(patternValue)) {
+    for (let i = 0; i < patternValue.length; i++) {
+      if (_isPatternMatchesPath(patternValue[i], inputPath)) {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  if (typeof patternValue === "function") {
+    return patternValue(inputPath);
+  }
+
+  if (isNodeOfType(t, inputPath.node, patternValue)) return true;
+  const evalResult = evaluate(inputPath);
+  if (!evalResult.confident || !inputPath.isPure()) return false;
+  return evalResult.value === patternValue;
+};
+
+module.exports = {
+  VOID_0,
+  // Types as Symbols
+  typeSymbols,
+  // This is required for resolving type aliases
+  isNodeOfType,
+  isPatternMatchesPath
+};
\ No newline at end of file
diff --git a/node_modules/babel-plugin-minify-simplify/lib/if-statement.js b/node_modules/babel-plugin-minify-simplify/lib/if-statement.js
new file mode 100644
index 00000000..f6ad4de2
--- /dev/null
+++ b/node_modules/babel-plugin-minify-simplify/lib/if-statement.js
@@ -0,0 +1,273 @@
+"use strict";
+
+const REPLACED = Symbol("replaced");
+
+const h = require("./helpers");
+
+module.exports = t => {
+  function mergeNestedIfs(path) {
+    const consequent = path.get("consequent");
+    const alternate = path.get("alternate"); // not nested if
+
+    if (!consequent.isIfStatement()) return; // there are no alternate nodes in both the if statements (nested)
+
+    if (alternate.node || consequent.get("alternate").node) return;
+    const test = path.get("test");
+    test.replaceWith(t.logicalExpression("&&", test.node, consequent.get("test").node));
+    consequent.replaceWith(t.clone(consequent.get("consequent").node));
+  } // No alternate, make into a guarded expression
+
+
+  function toGuardedExpression(path) {
+    const node = path.node;
+
+    if (node.consequent && !node.alternate && node.consequent.type === "ExpressionStatement") {
+      let op = "&&";
+
+      if (t.isUnaryExpression(node.test, {
+        operator: "!"
+      })) {
+        node.test = node.test.argument;
+        op = "||";
+      }
+
+      path.replaceWith(t.expressionStatement(t.logicalExpression(op, node.test, node.consequent.expression)));
+      return REPLACED;
+    }
+  } // both consequent and alternate are expressions, turn into ternary
+
+
+  function toTernary(path) {
+    const node = path.node;
+
+    if (t.isExpressionStatement(node.consequent) && t.isExpressionStatement(node.alternate)) {
+      path.replaceWith(t.conditionalExpression(node.test, node.consequent.expression, node.alternate.expression));
+      return REPLACED;
+    }
+  } // consequent and alternate are return -- conditional.
+
+
+  function toConditional(path) {
+    const node = path.node;
+
+    if (t.isReturnStatement(node.consequent) && t.isReturnStatement(node.alternate)) {
+      if (!node.consequent.argument && !node.alternate.argument) {
+        path.replaceWith(t.expressionStatement(node.test));
+        return REPLACED;
+      }
+
+      path.replaceWith(t.returnStatement(t.conditionalExpression(node.test, node.consequent.argument || h.VOID_0(t), node.alternate.argument || h.VOID_0(t))));
+      return REPLACED;
+    }
+  } // There is nothing after this If block. And one or both
+  // of the consequent and alternate are either expression statment
+  // or return statements.
+
+
+  function toReturn(path) {
+    const node = path.node;
+
+    if (!path.getSibling(path.key + 1).node && path.parentPath && path.parentPath.parentPath && path.parentPath.parentPath.isFunction()) {
+      // Only the consequent is a return, void the alternate.
+      if (t.isReturnStatement(node.consequent) && t.isExpressionStatement(node.alternate)) {
+        if (!node.consequent.argument) {
+          path.replaceWith(t.expressionStatement(t.logicalExpression("||", node.test, node.alternate.expression)));
+          return REPLACED;
+        }
+
+        path.replaceWith(t.returnStatement(t.conditionalExpression(node.test, node.consequent.argument || h.VOID_0(t), t.unaryExpression("void", node.alternate.expression, true))));
+        return REPLACED;
+      } // Only the alternate is a return, void the consequent.
+
+
+      if (t.isReturnStatement(node.alternate) && t.isExpressionStatement(node.consequent)) {
+        if (!node.alternate.argument) {
+          path.replaceWith(t.expressionStatement(t.logicalExpression("&&", node.test, node.consequent.expression)));
+          return REPLACED;
+        }
+
+        path.replaceWith(t.returnStatement(t.conditionalExpression(node.test, t.unaryExpression("void", node.consequent.expression, true), node.alternate.argument || h.VOID_0(t))));
+        return REPLACED;
+      }
+
+      if (t.isReturnStatement(node.consequent) && !node.alternate) {
+        if (!node.consequent.argument) {
+          path.replaceWith(t.expressionStatement(node.test));
+          return REPLACED;
+        } // This would only be worth it if the previous statement was an if
+        // because then we may merge to create a conditional.
+
+
+        if (path.getSibling(path.key - 1).isIfStatement()) {
+          path.replaceWith(t.returnStatement(t.conditionalExpression(node.test, node.consequent.argument || h.VOID_0(t), h.VOID_0(t))));
+          return REPLACED;
+        }
+      }
+
+      if (t.isReturnStatement(node.alternate) && !node.consequent) {
+        if (!node.alternate.argument) {
+          path.replaceWith(t.expressionStatement(node.test));
+          return REPLACED;
+        } // Same as above.
+
+
+        if (path.getSibling(path.key - 1).isIfStatement()) {
+          path.replaceWith(t.returnStatement(t.conditionalExpression(node.test, node.alternate.argument || h.VOID_0(t), h.VOID_0(t))));
+          return REPLACED;
+        }
+      }
+    }
+
+    let next = path.getSibling(path.key + 1); // If the next satatement(s) is an if statement and we can simplify that
+    // to potentailly be an expression (or a return) then this will make it
+    // easier merge.
+
+    if (next.isIfStatement()) {
+      next.pushContext(path.context);
+      next.visit();
+      next.popContext();
+      next = path.getSibling(path.key + 1);
+    } // Some other visitor might have deleted our node. OUR NODE ;_;
+
+
+    if (!path.node) {
+      return;
+    } // No alternate but the next statement is a return
+    // also turn into a return conditional
+
+
+    if (t.isReturnStatement(node.consequent) && !node.alternate && next.isReturnStatement()) {
+      const nextArg = next.node.argument || h.VOID_0(t);
+      next.remove();
+      path.replaceWith(t.returnStatement(t.conditionalExpression(node.test, node.consequent.argument || h.VOID_0(t), nextArg)));
+      return REPLACED;
+    } // Next is the last expression, turn into a return while void'ing the exprs
+
+
+    if (path.parentPath && path.parentPath.parentPath && path.parentPath.parentPath.isFunction() && !path.getSibling(path.key + 2).node && t.isReturnStatement(node.consequent) && !node.alternate && next.isExpressionStatement()) {
+      const nextExpr = next.node.expression;
+      next.remove();
+
+      if (node.consequent.argument) {
+        path.replaceWith(t.returnStatement(t.conditionalExpression(node.test, node.consequent.argument, t.unaryExpression("void", nextExpr, true))));
+        return REPLACED;
+      }
+
+      path.replaceWith(t.logicalExpression("||", node.test, nextExpr));
+      return REPLACED;
+    }
+  } // Remove else for if-return
+
+
+  function removeUnnecessaryElse(path) {
+    const node = path.node;
+    const consequent = path.get("consequent");
+    const alternate = path.get("alternate");
+
+    if (consequent.node && alternate.node && (consequent.isReturnStatement() || consequent.isBlockStatement() && t.isReturnStatement(consequent.node.body[consequent.node.body.length - 1])) && ( // don't hoist declarations
+    // TODO: validate declarations after fixing scope issues
+    alternate.isBlockStatement() ? !alternate.get("body").some(stmt => stmt.isVariableDeclaration({
+      kind: "let"
+    }) || stmt.isVariableDeclaration({
+      kind: "const"
+    })) : true)) {
+      path.insertAfter(alternate.isBlockStatement() ? alternate.node.body.map(el => t.clone(el)) : t.clone(alternate.node));
+      node.alternate = null;
+      return REPLACED;
+    }
+  }
+
+  function runTransforms(path) {
+    // ordered
+    const transforms = [toGuardedExpression, toTernary, toConditional, toReturn, removeUnnecessaryElse]; // run each of the replacement till we replace something
+    // which is identified by the Symbol(REPLACED) that each of the
+    // functions return when they replace something
+
+    for (var _i = 0; _i < transforms.length; _i++) {
+      const transform = transforms[_i];
+
+      if (transform(path) === REPLACED) {
+        break;
+      }
+    }
+  } // If the consequent is if and the altenrate is not then
+  // switch them out. That way we know we don't have to print
+  // a block.x
+
+
+  function switchConsequent(path) {
+    const node = path.node;
+
+    if (!node.alternate) {
+      return;
+    }
+
+    if (!t.isIfStatement(node.consequent)) {
+      return;
+    }
+
+    if (t.isIfStatement(node.alternate)) {
+      return;
+    }
+
+    node.test = t.unaryExpression("!", node.test, true);
+    var _ref = [node.consequent, node.alternate];
+    node.alternate = _ref[0];
+    node.consequent = _ref[1];
+  } // Make if statements with conditional returns in the body into
+  // an if statement that guards the rest of the block.
+
+
+  function conditionalReturnToGuards(path) {
+    const node = path.node;
+
+    if (!path.inList || !path.get("consequent").isBlockStatement() || node.alternate) {
+      return;
+    }
+
+    let ret;
+    let test;
+    const exprs = [];
+    const statements = node.consequent.body;
+
+    for (let i = 0, statement; statement = statements[i]; i++) {
+      if (t.isExpressionStatement(statement)) {
+        exprs.push(statement.expression);
+      } else if (t.isIfStatement(statement)) {
+        if (i < statements.length - 1) {
+          // This isn't the last statement. Bail.
+          return;
+        }
+
+        if (statement.alternate) {
+          return;
+        }
+
+        if (!t.isReturnStatement(statement.consequent)) {
+          return;
+        }
+
+        ret = statement.consequent;
+        test = statement.test;
+      } else {
+        return;
+      }
+    }
+
+    if (!test || !ret) {
+      return;
+    }
+
+    exprs.push(test);
+    const expr = exprs.length === 1 ? exprs[0] : t.sequenceExpression(exprs);
+    const replacement = t.logicalExpression("&&", node.test, expr);
+    path.replaceWith(t.ifStatement(replacement, ret, null));
+  }
+
+  return {
+    mergeNestedIfs,
+    simplify: runTransforms,
+    switchConsequent,
+    conditionalReturnToGuards
+  };
+};
\ No newline at end of file
diff --git a/node_modules/babel-plugin-minify-simplify/lib/index.js b/node_modules/babel-plugin-minify-simplify/lib/index.js
new file mode 100644
index 00000000..98b6190d
--- /dev/null
+++ b/node_modules/babel-plugin-minify-simplify/lib/index.js
@@ -0,0 +1,1179 @@
+"use strict";
+
+function _slicedToArray(arr, i) { return _arrayWithHoles(arr) || _iterableToArrayLimit(arr, i) || _nonIterableRest(); }
+
+function _nonIterableRest() { throw new TypeError("Invalid attempt to destructure non-iterable instance"); }
+
+function _iterableToArrayLimit(arr, i) { var _arr = []; var _n = true; var _d = false; var _e = undefined; try { for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) { _arr.push(_s.value); if (i && _arr.length === i) break; } } catch (err) { _d = true; _e = err; } finally { try { if (!_n && _i["return"] != null) _i["return"](); } finally { if (_d) throw _e; } } return _arr; }
+
+function _arrayWithHoles(arr) { if (Array.isArray(arr)) return arr; }
+
+module.exports = ({
+  types: t
+}) => {
+  const flipExpressions = require("babel-helper-flip-expressions")(t);
+
+  const toMultipleSequenceExpressions = require("babel-helper-to-multiple-sequence-expressions")(t);
+
+  const ifStatement = require("./if-statement")(t);
+
+  const conditionalExpression = require("./conditional-expression")(t);
+
+  const logicalExpression = require("./logical-expression")(t);
+
+  const assignmentExpression = require("./assignment-expression")(t);
+
+  const VOID_0 = t.unaryExpression("void", t.numericLiteral(0), true);
+  const condExprSeen = Symbol("condExprSeen");
+  const seqExprSeen = Symbol("seqExprSeen");
+  const shouldRevisit = Symbol("shouldRevisit");
+  return {
+    name: "minify-simplify",
+    visitor: {
+      Statement: {
+        exit(path) {
+          if (path.node[shouldRevisit]) {
+            delete path.node[shouldRevisit];
+            path.visit();
+          }
+        }
+
+      },
+      // CallExpression(path) {
+      // const { node } = path;
+
+      /* (function() {})() -> !function() {}()
+        There is a bug in babel in printing this. Disabling for now.
+        if (t.isFunctionExpression(node.callee) &&
+            (t.isExpressionStatement(parent) ||
+             (t.isSequenceExpression(parent) && parent.expressions[0] === node))
+        ) {
+          path.replaceWith(
+            t.callExpression(
+              t.unaryExpression("!", node.callee, true),
+              node.arguments
+            )
+          );
+          return;
+        }*/
+      // },
+      UnaryExpression: {
+        enter: [// Demorgans.
+        function (path) {
+          const node = path.node;
+
+          if (node.operator !== "!" || flipExpressions.hasSeen(node)) {
+            return;
+          }
+
+          const expr = node.argument; // We need to make sure that the return type will always be boolean.
+
+          if (!(t.isLogicalExpression(expr) || t.isConditionalExpression(expr) || t.isBinaryExpression(expr))) {
+            return;
+          }
+
+          if (t.isBinaryExpression(expr) && t.COMPARISON_BINARY_OPERATORS.indexOf(expr.operator) === -1) {
+            return;
+          }
+
+          if (flipExpressions.shouldFlip(expr, 1)) {
+            const newNode = flipExpressions.flip(expr);
+            path.replaceWith(newNode);
+          }
+        }, // !(a, b, c) -> a, b, !c
+        function (path) {
+          const node = path.node;
+
+          if (node.operator !== "!") {
+            return;
+          }
+
+          if (!t.isSequenceExpression(node.argument)) {
+            return;
+          }
+
+          const seq = node.argument.expressions;
+          const expr = seq[seq.length - 1];
+          seq[seq.length - 1] = t.unaryExpression("!", expr, true);
+          path.replaceWith(node.argument);
+        }, // !(a ? b : c) -> a ? !b : !c
+        function (path) {
+          const node = path.node;
+
+          if (node.operator !== "!") {
+            return;
+          }
+
+          if (!t.isConditional(node.argument)) {
+            return;
+          }
+
+          const cond = node.argument;
+          cond.alternate = t.unaryExpression("!", cond.alternate, true);
+          cond.consequent = t.unaryExpression("!", cond.consequent, true);
+          path.replaceWith(node.argument);
+        }]
+      },
+
+      BinaryExpression(path) {
+        if (["!=", "=="].indexOf(path.node.operator) !== -1) {
+          undefinedToNull(path.get("left"));
+          undefinedToNull(path.get("right"));
+        }
+      },
+
+      LogicalExpression: {
+        exit: logicalExpression.simplifyPatterns
+      },
+      AssignmentExpression: assignmentExpression.simplify,
+      ConditionalExpression: {
+        enter: [// !foo ? 'foo' : 'bar' -> foo ? 'bar' : 'foo'
+        // foo !== 'lol' ? 'foo' : 'bar' -> foo === 'lol' ? 'bar' : 'foo'
+        function flipIfOrConditional(path) {
+          const node = path.node;
+
+          if (!path.get("test").isLogicalExpression()) {
+            flipNegation(node);
+            return;
+          }
+
+          if (flipExpressions.shouldFlip(node.test)) {
+            node.test = flipExpressions.flip(node.test);
+            var _ref = [node.consequent, node.alternate];
+            node.alternate = _ref[0];
+            node.consequent = _ref[1];
+          }
+        }, conditionalExpression.simplifyPatterns],
+        exit: [// a ? x = foo : b ? x = bar : x = baz;
+        // x = a ? foo : b ? bar : baz;
+        function (topPath) {
+          if (!topPath.parentPath.isExpressionStatement() && !topPath.parentPath.isSequenceExpression()) {
+            return;
+          }
+
+          const mutations = [];
+          let firstLeft = null;
+          let operator = null;
+
+          function visit(path) {
+            if (path.isConditionalExpression()) {
+              let bail = visit(path.get("consequent"));
+
+              if (bail) {
+                return true;
+              }
+
+              bail = visit(path.get("alternate"));
+              return bail;
+            }
+
+            if (operator == null) {
+              operator = path.node.operator;
+            } else if (path.node.operator !== operator) {
+              return true;
+            }
+
+            if (!path.isAssignmentExpression() || !(path.get("left").isIdentifier() || path.get("left").isMemberExpression())) {
+              return true;
+            }
+
+            const left = path.get("left").node;
+
+            if (firstLeft == null) {
+              firstLeft = left;
+            } else if (!t.isNodesEquivalent(left, firstLeft)) {
+              return true;
+            }
+
+            mutations.push(() => path.replaceWith(path.get("right").node));
+          }
+
+          const bail = visit(topPath);
+
+          if (bail) {
+            return;
+          }
+
+          mutations.forEach(f => f());
+          topPath.replaceWith(t.assignmentExpression(operator, firstLeft, topPath.node));
+        }, // bar ? void 0 : void 0
+        // (bar, void 0)
+        // TODO: turn this into general equiv check
+        function (path) {
+          const node = path.node;
+
+          if (isVoid0(node.consequent) && isVoid0(node.alternate)) {
+            path.replaceWith(t.sequenceExpression([path.node.test, VOID_0]));
+          }
+        }, // bar ? void 0 : foo ? void 0 : <etc>
+        // bar || foo : void 0
+        // TODO: turn this into general equiv check
+        function (path) {
+          const node = path.node;
+
+          if (node[condExprSeen] || !isVoid0(node.consequent)) {
+            return;
+          }
+
+          node[condExprSeen] = true;
+          const tests = [node.test];
+          const mutations = [];
+          let alt;
+
+          for (let next = path.get("alternate"); next.isConditionalExpression(); next = next.get("alternate")) {
+            next.node[condExprSeen] = true;
+            alt = next.node.alternate;
+
+            if (isVoid0(next.node.consequent)) {
+              tests.push(next.node.test);
+              mutations.push(() => next.remove());
+            } else {
+              alt = next.node;
+              break;
+            }
+          }
+
+          if (tests.length === 1) {
+            return;
+          }
+
+          const test = tests.reduce((expr, curTest) => t.logicalExpression("||", expr, curTest));
+          path.replaceWith(t.conditionalExpression(test, VOID_0, alt));
+        }]
+      },
+      // concat
+      VariableDeclaration: {
+        enter: [// Put vars with no init at the top.
+        function (path) {
+          const node = path.node;
+
+          if (node.declarations.length < 2) {
+            return;
+          }
+
+          const inits = [];
+          const empty = [];
+          var _iteratorNormalCompletion = true;
+          var _didIteratorError = false;
+          var _iteratorError = undefined;
+
+          try {
+            for (var _iterator = node.declarations[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+              const decl = _step.value;
+
+              if (!decl.init) {
+                empty.push(decl);
+              } else {
+                inits.push(decl);
+              }
+            } // This is based on exprimintation but there is a significant
+            // imrpovement when we place empty vars at the top in smaller
+            // files. Whereas it hurts in larger files.
+
+          } catch (err) {
+            _didIteratorError = true;
+            _iteratorError = err;
+          } finally {
+            try {
+              if (!_iteratorNormalCompletion && _iterator.return != null) {
+                _iterator.return();
+              }
+            } finally {
+              if (_didIteratorError) {
+                throw _iteratorError;
+              }
+            }
+          }
+
+          if (this.fitsInSlidingWindow) {
+            node.declarations = empty.concat(inits);
+          } else {
+            node.declarations = inits.concat(empty);
+          }
+        }]
+      },
+      Function: {
+        exit(path) {
+          earlyReturnTransform(path);
+
+          if (!path.node[shouldRevisit]) {
+            return;
+          }
+
+          delete path.node[shouldRevisit];
+          path.visit();
+        }
+
+      },
+      For: {
+        enter: earlyContinueTransform,
+        exit: earlyContinueTransform
+      },
+      ForStatement: {
+        // Merge previous expressions in the init part of the for.
+        enter(path) {
+          const node = path.node;
+
+          if (!path.inList || node.init && !t.isExpression(node.init)) {
+            return;
+          }
+
+          const prev = path.getSibling(path.key - 1);
+          let consumed = false;
+
+          if (prev.isVariableDeclaration()) {
+            let referencedOutsideLoop = false; // we don't care if vars are referenced outside the loop as they are fn scope
+
+            if (prev.node.kind === "let" || prev.node.kind === "const") {
+              const ids = Object.keys(prev.getBindingIdentifiers());
+
+              idloop: for (let i = 0; i < ids.length; i++) {
+                const binding = prev.scope.bindings[ids[i]]; // TODO
+                // Temporary Fix
+                // if there is no binding, we assume it is referenced outside
+                // and deopt to avoid bugs
+
+                if (!binding) {
+                  referencedOutsideLoop = true;
+                  break idloop;
+                }
+
+                const refs = binding.referencePaths;
+
+                for (let j = 0; j < refs.length; j++) {
+                  if (!isAncestor(path, refs[j])) {
+                    referencedOutsideLoop = true;
+                    break idloop;
+                  }
+                }
+              }
+            }
+
+            if (!node.init && !referencedOutsideLoop) {
+              node.init = prev.node;
+              consumed = true;
+            }
+          } else if (prev.isExpressionStatement()) {
+            const expr = prev.node.expression;
+
+            if (node.init) {
+              if (t.isSequenceExpression(expr)) {
+                expr.expressions.push(node.init);
+                node.init = expr;
+              } else {
+                node.init = t.sequenceExpression([expr, node.init]);
+              }
+            } else {
+              node.init = expr;
+            }
+
+            consumed = true;
+          }
+
+          if (consumed) {
+            prev.remove();
+          }
+        },
+
+        exit(path) {
+          const node = path.node;
+
+          if (!node.test) {
+            return;
+          }
+
+          if (!path.get("body").isBlockStatement()) {
+            const bodyNode = path.get("body").node;
+
+            if (!t.isIfStatement(bodyNode)) {
+              return;
+            }
+
+            if (t.isBreakStatement(bodyNode.consequent, {
+              label: null
+            })) {
+              node.test = t.logicalExpression("&&", node.test, t.unaryExpression("!", bodyNode.test, true));
+              node.body = bodyNode.alternate || t.emptyStatement();
+              return;
+            }
+
+            if (t.isBreakStatement(bodyNode.alternate, {
+              label: null
+            })) {
+              node.test = t.logicalExpression("&&", node.test, bodyNode.test);
+              node.body = bodyNode.consequent || t.emptyStatement();
+              return;
+            }
+
+            return;
+          }
+
+          const statements = node.body.body;
+          const exprs = [];
+          let ifStatement = null;
+          let breakAt = null;
+          let i = 0;
+
+          for (let statement; statement = statements[i]; i++) {
+            if (t.isIfStatement(statement)) {
+              if (t.isBreakStatement(statement.consequent, {
+                label: null
+              })) {
+                ifStatement = statement;
+                breakAt = "consequent";
+              } else if (t.isBreakStatement(statement.alternate, {
+                label: null
+              })) {
+                ifStatement = statement;
+                breakAt = "alternate";
+              }
+
+              break;
+            } // A statement appears before the break statement then bail.
+
+
+            if (!t.isExpressionStatement(statement)) {
+              return;
+            }
+
+            exprs.push(statement.expression);
+          }
+
+          if (!ifStatement) {
+            return;
+          }
+
+          const rest = [];
+
+          if (breakAt === "consequent") {
+            if (t.isBlockStatement(ifStatement.alternate)) {
+              rest.push(...ifStatement.alternate.body);
+            } else if (ifStatement.alternate) {
+              rest.push(ifStatement.alternate);
+            }
+          } else {
+            if (t.isBlockStatement(ifStatement.consequent)) {
+              rest.push(...ifStatement.consequent.body);
+            } else if (ifStatement.consequent) {
+              rest.push(ifStatement.consequent);
+            }
+          }
+
+          rest.push(...statements.slice(i + 1));
+          const test = breakAt === "consequent" ? t.unaryExpression("!", ifStatement.test, true) : ifStatement.test;
+          let expr;
+
+          if (exprs.length === 1) {
+            expr = t.sequenceExpression([exprs[0], test]);
+          } else if (exprs.length) {
+            exprs.push(test);
+            expr = t.sequenceExpression(exprs);
+          } else {
+            expr = test;
+          }
+
+          node.test = t.logicalExpression("&&", node.test, expr);
+
+          if (rest.length === 1) {
+            node.body = rest[0];
+          } else if (rest.length) {
+            node.body = t.blockStatement(rest);
+          } else {
+            node.body = t.emptyStatement();
+          }
+        }
+
+      },
+
+      Program(path) {
+        // An approximation of the resultant gzipped code after minification
+        this.fitsInSlidingWindow = path.getSource().length / 10 < 33000;
+        const node = path.node;
+        const statements = toMultipleSequenceExpressions(node.body);
+
+        if (!statements.length) {
+          return;
+        }
+
+        node.body = statements;
+      },
+
+      BlockStatement: {
+        enter(path) {
+          const node = path.node,
+                parent = path.parent;
+          const top = [];
+          const bottom = [];
+
+          for (let i = 0; i < node.body.length; i++) {
+            const bodyNode = node.body[i];
+
+            if (t.isFunctionDeclaration(bodyNode)) {
+              top.push(bodyNode);
+            } else {
+              bottom.push(bodyNode);
+            }
+          }
+
+          const statements = top.concat(toMultipleSequenceExpressions(bottom));
+
+          if (!statements.length) {
+            return;
+          }
+
+          if (statements.length > 1 || needsBlock(node, parent) || node.directives) {
+            node.body = statements;
+            return;
+          }
+
+          if (statements.length) {
+            path.replaceWith(statements[0]);
+            return;
+          }
+        },
+
+        exit(path) {
+          const node = path.node,
+                parent = path.parent;
+
+          if (t.isArrowFunctionExpression(parent) && node.body.length === 1 && t.isReturnStatement(node.body[0]) && node.body[0].argument !== null) {
+            path.replaceWith(node.body[0].argument);
+            return;
+          }
+
+          if (needsBlock(node, parent)) {
+            return;
+          }
+
+          if (node.body.length === 1) {
+            path.get("body")[0].inList = false;
+            path.replaceWith(node.body[0]);
+            return;
+          }
+
+          if (node.body.length === 0) {
+            path.replaceWith(t.emptyStatement());
+            return;
+          } // Check if oppurtinties to merge statements are available.
+
+
+          const statements = node.body;
+
+          if (!statements.length) {
+            return;
+          }
+
+          var _iteratorNormalCompletion2 = true;
+          var _didIteratorError2 = false;
+          var _iteratorError2 = undefined;
+
+          try {
+            for (var _iterator2 = statements[Symbol.iterator](), _step2; !(_iteratorNormalCompletion2 = (_step2 = _iterator2.next()).done); _iteratorNormalCompletion2 = true) {
+              const statement = _step2.value;
+
+              if (!t.isExpressionStatement(statement)) {
+                return;
+              }
+            }
+          } catch (err) {
+            _didIteratorError2 = true;
+            _iteratorError2 = err;
+          } finally {
+            try {
+              if (!_iteratorNormalCompletion2 && _iterator2.return != null) {
+                _iterator2.return();
+              }
+            } finally {
+              if (_didIteratorError2) {
+                throw _iteratorError2;
+              }
+            }
+          }
+
+          path.visit();
+        }
+
+      },
+      ThrowStatement: createPrevExpressionEater("throw"),
+      // Try to merge previous statements into a sequence
+      ReturnStatement: {
+        enter: [createPrevExpressionEater("return"), // Remove return if last statement with no argument.
+        // Replace return with `void` argument with argument.
+        function (path) {
+          const node = path.node;
+
+          if (!path.parentPath.parentPath.isFunction() || path.getSibling(path.key + 1).node) {
+            return;
+          }
+
+          if (!node.argument) {
+            path.remove();
+            return;
+          }
+
+          if (t.isUnaryExpression(node.argument, {
+            operator: "void"
+          })) {
+            path.replaceWith(node.argument.argument);
+          }
+        }]
+      },
+      // turn blocked ifs into single statements
+      IfStatement: {
+        exit: [ifStatement.mergeNestedIfs, ifStatement.simplify, ifStatement.switchConsequent, ifStatement.conditionalReturnToGuards, createPrevExpressionEater("if")]
+      },
+
+      WhileStatement(path) {
+        const node = path.node;
+        path.replaceWith(t.forStatement(null, node.test, null, node.body));
+      },
+
+      ForInStatement: createPrevExpressionEater("for-in"),
+      // Flatten sequence expressions.
+      SequenceExpression: {
+        exit(path) {
+          if (path.node[seqExprSeen]) {
+            return;
+          }
+
+          function flatten(node) {
+            node[seqExprSeen] = true;
+            const ret = [];
+            var _iteratorNormalCompletion3 = true;
+            var _didIteratorError3 = false;
+            var _iteratorError3 = undefined;
+
+            try {
+              for (var _iterator3 = node.expressions[Symbol.iterator](), _step3; !(_iteratorNormalCompletion3 = (_step3 = _iterator3.next()).done); _iteratorNormalCompletion3 = true) {
+                const n = _step3.value;
+
+                if (t.isSequenceExpression(n)) {
+                  ret.push(...flatten(n));
+                } else {
+                  ret.push(n);
+                }
+              }
+            } catch (err) {
+              _didIteratorError3 = true;
+              _iteratorError3 = err;
+            } finally {
+              try {
+                if (!_iteratorNormalCompletion3 && _iterator3.return != null) {
+                  _iterator3.return();
+                }
+              } finally {
+                if (_didIteratorError3) {
+                  throw _iteratorError3;
+                }
+              }
+            }
+
+            return ret;
+          }
+
+          path.node.expressions = flatten(path.node);
+        }
+
+      },
+
+      SwitchCase(path) {
+        const node = path.node;
+
+        if (!node.consequent.length) {
+          return;
+        }
+
+        node.consequent = toMultipleSequenceExpressions(node.consequent);
+      },
+
+      SwitchStatement: {
+        exit: [// Convert switch statements with all returns in their cases
+        // to return conditional.
+        function (path) {
+          const node = path.node; // Need to be careful of side-effects.
+
+          if (!t.isIdentifier(node.discriminant)) {
+            return;
+          }
+
+          if (!node.cases.length) {
+            return;
+          }
+
+          const consTestPairs = [];
+          let fallThru = [];
+          let defaultRet;
+          var _iteratorNormalCompletion4 = true;
+          var _didIteratorError4 = false;
+          var _iteratorError4 = undefined;
+
+          try {
+            for (var _iterator4 = node.cases[Symbol.iterator](), _step4; !(_iteratorNormalCompletion4 = (_step4 = _iterator4.next()).done); _iteratorNormalCompletion4 = true) {
+              const switchCase = _step4.value;
+
+              if (switchCase.consequent.length > 1) {
+                return;
+              }
+
+              const cons = switchCase.consequent[0]; // default case
+
+              if (!switchCase.test) {
+                if (!t.isReturnStatement(cons)) {
+                  return;
+                }
+
+                defaultRet = cons;
+                continue;
+              }
+
+              if (!switchCase.consequent.length) {
+                fallThru.push(switchCase.test);
+                continue;
+              } // TODO: can we void it?
+
+
+              if (!t.isReturnStatement(cons)) {
+                return;
+              }
+
+              let test = t.binaryExpression("===", node.discriminant, switchCase.test);
+
+              if (fallThru.length && !defaultRet) {
+                test = fallThru.reduceRight((right, test) => t.logicalExpression("||", t.binaryExpression("===", node.discriminant, test), right), test);
+              }
+
+              fallThru = [];
+              consTestPairs.push([test, cons.argument || VOID_0]);
+            } // Bail if we have any remaining fallthrough
+
+          } catch (err) {
+            _didIteratorError4 = true;
+            _iteratorError4 = err;
+          } finally {
+            try {
+              if (!_iteratorNormalCompletion4 && _iterator4.return != null) {
+                _iterator4.return();
+              }
+            } finally {
+              if (_didIteratorError4) {
+                throw _iteratorError4;
+              }
+            }
+          }
+
+          if (fallThru.length) {
+            return;
+          } // We need the default to be there to make sure there is an oppurtinity
+          // not to return.
+
+
+          if (!defaultRet) {
+            if (path.inList) {
+              const nextPath = path.getSibling(path.key + 1);
+
+              if (nextPath.isReturnStatement()) {
+                defaultRet = nextPath.node;
+                nextPath.remove();
+              } else if (!nextPath.node && path.parentPath.parentPath.isFunction()) {
+                // If this is the last statement in a function we just fake a void return.
+                defaultRet = t.returnStatement(VOID_0);
+              } else {
+                return;
+              }
+            } else {
+              return;
+            }
+          }
+
+          const cond = consTestPairs.reduceRight((alt, [test, cons]) => t.conditionalExpression(test, cons, alt), defaultRet.argument || VOID_0);
+          path.replaceWith(t.returnStatement(cond)); // Maybe now we can merge with some previous switch statement.
+
+          if (path.inList) {
+            const prev = path.getSibling(path.key - 1);
+
+            if (prev.isSwitchStatement()) {
+              prev.visit();
+            }
+          }
+        }, // Convert switches into conditionals.
+        function (path) {
+          const node = path.node; // Need to be careful of side-effects.
+
+          if (!t.isIdentifier(node.discriminant)) {
+            return;
+          }
+
+          if (!node.cases.length) {
+            return;
+          }
+
+          const exprTestPairs = [];
+          let fallThru = [];
+          let defaultExpr;
+          var _iteratorNormalCompletion5 = true;
+          var _didIteratorError5 = false;
+          var _iteratorError5 = undefined;
+
+          try {
+            for (var _iterator5 = node.cases[Symbol.iterator](), _step5; !(_iteratorNormalCompletion5 = (_step5 = _iterator5.next()).done); _iteratorNormalCompletion5 = true) {
+              const switchCase = _step5.value;
+
+              if (!switchCase.test) {
+                if (switchCase.consequent.length !== 1) {
+                  return;
+                }
+
+                if (!t.isExpressionStatement(switchCase.consequent[0])) {
+                  return;
+                }
+
+                defaultExpr = switchCase.consequent[0].expression;
+                continue;
+              }
+
+              if (!switchCase.consequent.length) {
+                fallThru.push(switchCase.test);
+                continue;
+              }
+
+              const _switchCase$consequen = _slicedToArray(switchCase.consequent, 2),
+                    cons = _switchCase$consequen[0],
+                    breakStatement = _switchCase$consequen[1];
+
+              if (switchCase === node.cases[node.cases.length - 1]) {
+                if (breakStatement && !t.isBreakStatement(breakStatement)) {
+                  return;
+                }
+              } else if (!t.isBreakStatement(breakStatement)) {
+                return;
+              }
+
+              if (!t.isExpressionStatement(cons) || switchCase.consequent.length > 2) {
+                return;
+              }
+
+              let test = t.binaryExpression("===", node.discriminant, switchCase.test);
+
+              if (fallThru.length && !defaultExpr) {
+                test = fallThru.reduceRight((right, test) => t.logicalExpression("||", t.binaryExpression("===", node.discriminant, test), right), test);
+              }
+
+              fallThru = [];
+              exprTestPairs.push([test, cons.expression]);
+            }
+          } catch (err) {
+            _didIteratorError5 = true;
+            _iteratorError5 = err;
+          } finally {
+            try {
+              if (!_iteratorNormalCompletion5 && _iterator5.return != null) {
+                _iterator5.return();
+              }
+            } finally {
+              if (_didIteratorError5) {
+                throw _iteratorError5;
+              }
+            }
+          }
+
+          if (fallThru.length) {
+            return;
+          }
+
+          const cond = exprTestPairs.reduceRight((alt, [test, cons]) => t.conditionalExpression(test, cons, alt), defaultExpr || VOID_0);
+          path.replaceWith(cond);
+        }, function (path) {
+          const node = path.node;
+
+          if (!node.cases.length) {
+            return;
+          }
+
+          const lastCase = path.get("cases")[node.cases.length - 1];
+
+          if (!lastCase.node.consequent.length) {
+            return;
+          }
+
+          const potentialBreak = lastCase.get("consequent")[lastCase.node.consequent.length - 1];
+
+          if (t.isBreakStatement(potentialBreak) && potentialBreak.node.label === null) {
+            potentialBreak.remove();
+          }
+        }, createPrevExpressionEater("switch")]
+      }
+    }
+  };
+
+  function flipNegation(node) {
+    if (!node.consequent || !node.alternate) {
+      return;
+    }
+
+    const test = node.test;
+    let flip = false;
+
+    if (t.isBinaryExpression(test)) {
+      if (test.operator === "!==") {
+        test.operator = "===";
+        flip = true;
+      }
+
+      if (test.operator === "!=") {
+        test.operator = "==";
+        flip = true;
+      }
+    }
+
+    if (t.isUnaryExpression(test, {
+      operator: "!"
+    })) {
+      node.test = test.argument;
+      flip = true;
+    }
+
+    if (flip) {
+      const consequent = node.consequent;
+      node.consequent = node.alternate;
+      node.alternate = consequent;
+    }
+  }
+
+  function needsBlock(node, parent) {
+    return t.isFunction(parent) && node === parent.body || t.isTryStatement(parent) || t.isCatchClause(parent) || t.isSwitchStatement(parent) || isSingleBlockScopeDeclaration(node) && (t.isIfStatement(parent) || t.isLoop(parent));
+  }
+
+  function isSingleBlockScopeDeclaration(block) {
+    return t.isBlockStatement(block) && block.body.length === 1 && (t.isVariableDeclaration(block.body[0], {
+      kind: "let"
+    }) || t.isVariableDeclaration(block.body[0], {
+      kind: "const"
+    }) || t.isFunctionDeclaration(block.body[0]));
+  }
+
+  function isVoid0(expr) {
+    return expr === VOID_0 || t.isUnaryExpression(expr, {
+      operator: "void"
+    }) && t.isNumericLiteral(expr.argument, {
+      value: 0
+    });
+  }
+
+  function earlyReturnTransform(path) {
+    const block = path.get("body");
+
+    if (!block.isBlockStatement()) {
+      return;
+    }
+
+    const body = block.get("body");
+
+    for (let i = body.length - 1; i >= 0; i--) {
+      const statement = body[i];
+
+      if (t.isIfStatement(statement.node) && !statement.node.alternate && t.isReturnStatement(statement.node.consequent) && !statement.node.consequent.argument) {
+        genericEarlyExitTransform(statement);
+      }
+    }
+  }
+
+  function earlyContinueTransform(path) {
+    const block = path.get("body");
+
+    if (!block.isBlockStatement()) {
+      return;
+    }
+
+    let body = block.get("body");
+
+    for (let i = body.length - 1; i >= 0; i--) {
+      const statement = body[i];
+
+      if (t.isIfStatement(statement.node) && !statement.node.alternate && t.isContinueStatement(statement.node.consequent) && !statement.node.consequent.label) {
+        genericEarlyExitTransform(statement);
+      }
+    } // because we might have folded or removed statements
+
+
+    body = block.get("body"); // We may have reduced the body to a single statement.
+
+    if (body.length === 1 && !needsBlock(block.node, path.node)) {
+      block.replaceWith(body[0].node);
+    }
+  }
+
+  function genericEarlyExitTransform(path) {
+    const node = path.node;
+    const statements = path.parentPath.get(path.listKey).slice(path.key + 1).filter(stmt => !stmt.isFunctionDeclaration()); // deopt for any block scoped bindings
+    // issue#399
+
+    const deopt = !statements.every(stmt => {
+      if (!(stmt.isVariableDeclaration({
+        kind: "let"
+      }) || stmt.isVariableDeclaration({
+        kind: "const"
+      }))) {
+        return true;
+      }
+
+      const ids = Object.keys(stmt.getBindingIdentifiers());
+
+      for (var _i2 = 0; _i2 < ids.length; _i2++) {
+        const id = ids[_i2];
+        const binding = path.scope.getBinding(id); // TODO
+        // Temporary Fix
+        // if there is no binding, we assume it is referenced outside
+        // and deopt to avoid bugs
+
+        if (!binding) {
+          return false;
+        }
+
+        const refs = [...binding.referencePaths, ...binding.constantViolations];
+
+        for (var _i3 = 0; _i3 < refs.length; _i3++) {
+          const ref = refs[_i3];
+          if (!ref.isIdentifier()) return false;
+          const fnParent = ref.getFunctionParent(); // TODO
+          // Usage of scopes and bindings in simplify plugin results in
+          // undefined bindings because scope changes are not updated in the
+          // scope tree. So, we deopt whenever we encounter one such issue
+          // and not perform the transformation
+
+          if (!fnParent) {
+            return false;
+          }
+
+          if (fnParent.scope !== path.scope) return false;
+        }
+      }
+
+      return true;
+    });
+
+    if (deopt) {
+      path.visit();
+      return false;
+    }
+
+    if (!statements.length) {
+      path.replaceWith(t.expressionStatement(node.test));
+      return;
+    }
+
+    const test = node.test;
+
+    if (t.isBinaryExpression(test) && test.operator === "!==") {
+      test.operator = "===";
+    } else if (t.isBinaryExpression(test) && test.operator === "!=") {
+      test.operator = "==";
+    } else if (t.isUnaryExpression(test, {
+      operator: "!"
+    })) {
+      node.test = test.argument;
+    } else {
+      node.test = t.unaryExpression("!", node.test, true);
+    }
+
+    path.get("consequent").replaceWith(t.blockStatement(statements.map(stmt => t.clone(stmt.node))));
+    let l = statements.length;
+
+    while (l-- > 0) {
+      if (!statements[l].isFunctionDeclaration()) {
+        path.getSibling(path.key + 1).remove();
+      }
+    } // this should take care of removing the block
+
+
+    path.visit();
+  }
+
+  function createPrevExpressionEater(keyword) {
+    let key;
+
+    switch (keyword) {
+      case "switch":
+        key = "discriminant";
+        break;
+
+      case "throw":
+      case "return":
+        key = "argument";
+        break;
+
+      case "if":
+        key = "test";
+        break;
+
+      case "for-in":
+        key = "right";
+        break;
+    }
+
+    return function (path) {
+      if (!path.inList) {
+        return;
+      }
+
+      const node = path.node;
+      const prev = path.getSibling(path.key - 1);
+
+      if (!prev.isExpressionStatement()) {
+        return;
+      }
+
+      let seq = prev.node.expression;
+
+      if (node[key]) {
+        if (t.isSequenceExpression(seq)) {
+          seq.expressions.push(node[key]);
+        } else {
+          seq = t.sequenceExpression([seq, node[key]]);
+        }
+      } else {
+        if (t.isSequenceExpression(seq)) {
+          const lastExpr = seq.expressions[seq.expressions.length - 1];
+          seq.expressions[seq.expressions.length - 1] = t.unaryExpression("void", lastExpr, true);
+        } else {
+          seq = t.unaryExpression("void", seq, true);
+        }
+      }
+
+      if (seq) {
+        node[key] = seq;
+        prev.remove(); // Since we were able to merge some stuff it's possible that this has opened
+        // oppurtinties for other transforms to happen.
+        // TODO: Look into changing the traversal order from bottom to up to avoid
+        // having to revisit things.
+
+        if (path.parentPath.parent) {
+          path.parentPath.parent[shouldRevisit] = true;
+        }
+      }
+    };
+  } // path1 -> path2
+  // is path1 an ancestor of path2
+
+
+  function isAncestor(path1, path2) {
+    return !!path2.findParent(parent => parent === path1);
+  }
+
+  function isPureVoid(path) {
+    return path.isUnaryExpression({
+      operator: "void"
+    }) && path.isPure();
+  }
+
+  function isGlobalUndefined(path) {
+    return path.isIdentifier({
+      name: "undefined"
+    }) && !path.scope.getBinding("undefined");
+  }
+
+  function undefinedToNull(path) {
+    if (isGlobalUndefined(path) || isPureVoid(path)) {
+      path.replaceWith(t.nullLiteral());
+    }
+  }
+};
\ No newline at end of file
diff --git a/node_modules/babel-plugin-minify-simplify/lib/logical-expression.js b/node_modules/babel-plugin-minify-simplify/lib/logical-expression.js
new file mode 100644
index 00000000..a91af230
--- /dev/null
+++ b/node_modules/babel-plugin-minify-simplify/lib/logical-expression.js
@@ -0,0 +1,75 @@
+"use strict";
+
+const h = require("./helpers");
+
+const PatternMatch = require("./pattern-match");
+
+const evaluate = require("babel-helper-evaluate-path");
+
+module.exports = t => {
+  const OP_AND = input => input === "&&";
+
+  const OP_OR = input => input === "||";
+
+  function simplifyPatterns(path) {
+    // cache of evaluate(path)
+    const evaluateMemo = new Map();
+
+    const TRUTHY = input => {
+      // !NaN and !undefined are truthy
+      // separate check here as they are considered impure by babel
+      if (input.isUnaryExpression() && input.get("argument").isIdentifier()) {
+        if (input.node.argument.name === "NaN" || input.node.argument.name === "undefined") {
+          return true;
+        }
+      }
+
+      const evalResult = evaluate(input);
+      evaluateMemo.set(input, evalResult);
+      return evalResult.confident && input.isPure() && evalResult.value;
+    };
+
+    const FALSY = input => {
+      // NaN and undefined are falsy
+      // separate check here as they are considered impure by babel
+      if (input.isIdentifier()) {
+        if (input.node.name === "NaN" || input.node.name === "undefined") {
+          return true;
+        }
+      }
+
+      const evalResult = evaluate(input);
+      evaluateMemo.set(input, evalResult);
+      return evalResult.confident && input.isPure() && !evalResult.value;
+    };
+
+    const _h$typeSymbols = h.typeSymbols(t),
+          EX = _h$typeSymbols.Expression; // Convention:
+    // [left, operator, right, handler(leftNode, rightNode)]
+
+
+    const matcher = new PatternMatch([[TRUTHY, OP_AND, EX, (l, r) => r], [FALSY, OP_AND, EX, l => l], [TRUTHY, OP_OR, EX, l => l], [FALSY, OP_OR, EX, (l, r) => r]]);
+    const left = path.get("left");
+    const right = path.get("right");
+    const operator = path.node.operator;
+    const result = matcher.match([left, operator, right], h.isPatternMatchesPath(t));
+
+    if (result.match) {
+      // here we are sure that left.evaluate is always confident becuase
+      // it satisfied one of TRUTHY/FALSY paths
+      let value;
+
+      if (evaluateMemo.has(left)) {
+        value = evaluateMemo.get(left).value;
+      } else {
+        value = evaluate(left).value;
+      }
+
+      path.replaceWith(result.value(t.valueToNode(value), right.node));
+    }
+  }
+
+  return {
+    simplifyPatterns
+  };
+};
\ No newline at end of file
diff --git a/node_modules/babel-plugin-minify-simplify/lib/pattern-match.js b/node_modules/babel-plugin-minify-simplify/lib/pattern-match.js
new file mode 100644
index 00000000..e5c34f6d
--- /dev/null
+++ b/node_modules/babel-plugin-minify-simplify/lib/pattern-match.js
@@ -0,0 +1,156 @@
+"use strict";
+
+function _toArray(arr) { return _arrayWithHoles(arr) || _iterableToArray(arr) || _nonIterableRest(); }
+
+function _nonIterableRest() { throw new TypeError("Invalid attempt to destructure non-iterable instance"); }
+
+function _iterableToArray(iter) { if (Symbol.iterator in Object(iter) || Object.prototype.toString.call(iter) === "[object Arguments]") return Array.from(iter); }
+
+function _arrayWithHoles(arr) { if (Array.isArray(arr)) return arr; }
+
+const LEAF_NODE = Symbol("LEAF_NODE");
+module.exports = class PatternMatch {
+  constructor(patterns) {
+    this.decisionTree = this.makeDecisionTree(patterns);
+  }
+
+  handle(input, isMatch) {
+    const result = this.match(input, isMatch);
+
+    if (!result.match) {
+      throw new Error("No Match Found for " + input.toString());
+    }
+
+    if (typeof result.value !== "function") {
+      throw new Error("Expecting a function. Instead got - " + result.value.toString());
+    }
+
+    result.value.call(null, input, result.keys);
+  }
+
+  match(input, isMatch = (a, b) => a === b) {
+    let current = this.decisionTree;
+    const result = {
+      match: false,
+      value: void 0,
+      keys: []
+    }; // to handle falsy keys
+
+    const NO_MATCH = Symbol("NO_MATCH");
+
+    for (let i = 0; i < input.length; i++) {
+      let matchedKey = NO_MATCH; // because map doesn't support custom key equal function
+
+      var _iteratorNormalCompletion = true;
+      var _didIteratorError = false;
+      var _iteratorError = undefined;
+
+      try {
+        for (var _iterator = current.keys()[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+          const key = _step.value;
+
+          if (isMatch(key, input[i])) {
+            matchedKey = key;
+            result.keys.push(matchedKey);
+            break;
+          }
+        }
+      } catch (err) {
+        _didIteratorError = true;
+        _iteratorError = err;
+      } finally {
+        try {
+          if (!_iteratorNormalCompletion && _iterator.return != null) {
+            _iterator.return();
+          }
+        } finally {
+          if (_didIteratorError) {
+            throw _iteratorError;
+          }
+        }
+      }
+
+      if (matchedKey !== NO_MATCH) {
+        current = current.get(matchedKey);
+
+        if (i === input.length - 1) {
+          if (current.has(LEAF_NODE)) {
+            result.match = true;
+            result.value = current.get(LEAF_NODE);
+          }
+
+          break;
+        }
+      } else {
+        break;
+      }
+    }
+
+    return result;
+  }
+
+  makeDecisionTree(patterns) {
+    // order of keys in a Map is the order of insertion
+    const root = new Map();
+    var _iteratorNormalCompletion2 = true;
+    var _didIteratorError2 = false;
+    var _iteratorError2 = undefined;
+
+    try {
+      for (var _iterator2 = patterns[Symbol.iterator](), _step2; !(_iteratorNormalCompletion2 = (_step2 = _iterator2.next()).done); _iteratorNormalCompletion2 = true) {
+        const pattern = _step2.value;
+        make(root, pattern);
+      }
+    } catch (err) {
+      _didIteratorError2 = true;
+      _iteratorError2 = err;
+    } finally {
+      try {
+        if (!_iteratorNormalCompletion2 && _iterator2.return != null) {
+          _iterator2.return();
+        }
+      } finally {
+        if (_didIteratorError2) {
+          throw _iteratorError2;
+        }
+      }
+    }
+
+    return root;
+
+    function make(parent, pattern) {
+      if (pattern.length < 2) {
+        throw new Error("at least 2 elements required in a pattern");
+      }
+
+      if (pattern.length === 2) {
+        if (parent.has(pattern[0])) {
+          const pattern0 = parent.get(pattern[0]);
+
+          if (!pattern0.has(LEAF_NODE)) {
+            pattern0.set(LEAF_NODE, pattern[1]);
+          } // here we don't handle duplicates
+          // this pattern would have already been matched
+
+        } else {
+          parent.set(pattern[0], new Map([[LEAF_NODE, pattern[1]]]));
+        }
+
+        return parent;
+      }
+
+      const _pattern = _toArray(pattern),
+            current = _pattern[0],
+            rest = _pattern.slice(1);
+
+      if (parent.has(current)) {
+        make(parent.get(current), rest);
+      } else {
+        parent.set(current, make(new Map(), rest));
+      }
+
+      return parent;
+    }
+  }
+
+};
\ No newline at end of file