Class Es6RewriteModules

  • All Implemented Interfaces:
    CompilerPass, HotSwapCompilerPass, NodeTraversal.Callback

    public final class Es6RewriteModules
    extends java.lang.Object
    implements HotSwapCompilerPass, NodeTraversal.Callback
    Rewrites a ES6 module into a form that can be safely concatenated. Note that we treat a file as an ES6 module if it has at least one import or export statement.

    Also rewrites any goog.{require,requireType,forwardDeclare,goog.module.get} calls that are either in an ES module or of an ES module using goog.declareModuleId.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void hotSwapScript​(Node scriptNode, Node originalRoot)
      Process the JS with root node root.
      static boolean isEs6ModuleRoot​(Node scriptNode)
      Return whether or not the given script node represents an ES6 module file.
      void process​(Node externs, Node root)
      Process the JS with root node root.
      boolean shouldTraverse​(NodeTraversal nodeTraversal, Node n, Node parent)
      Visits a node in preorder (before its children) and decides whether its children should be traversed.
      void visit​(NodeTraversal t, Node n, Node parent)
      Visits a node in postorder (after its children).
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Method Detail

      • isEs6ModuleRoot

        public static boolean isEs6ModuleRoot​(Node scriptNode)
        Return whether or not the given script node represents an ES6 module file.
      • process

        public void process​(Node externs,
                            Node root)
        Description copied from interface: CompilerPass
        Process the JS with root node root. Can modify the contents of each Node tree
        Specified by:
        process in interface CompilerPass
        Parameters:
        externs - Top of external JS tree
        root - Top of JS tree
      • hotSwapScript

        public void hotSwapScript​(Node scriptNode,
                                  Node originalRoot)
        Description copied from interface: HotSwapCompilerPass
        Process the JS with root node root. This is supposed to be significantly faster compared to corresponding full-compiler passes.
        Specified by:
        hotSwapScript in interface HotSwapCompilerPass
        Parameters:
        scriptNode - Root node corresponding to the file that is modified, should be of type Token.SCRIPT.
        originalRoot - Root node corresponding to the original version of the file that is modified. Should be of type token.SCRIPT.
      • visit

        public void visit​(NodeTraversal t,
                          Node n,
                          Node parent)
        Description copied from interface: NodeTraversal.Callback
        Visits a node in postorder (after its children). A node is visited in postorder iff NodeTraversal.Callback.shouldTraverse(NodeTraversal, Node, Node) returned true for its parent. In particular, the root node is never visited in postorder.

        Siblings are always visited left-to-right.

        Implementations can have side-effects (e.g. modify the parse tree). Removing the current node is legal, but removing or reordering nodes above the current node may cause nodes to be visited twice or not at all.

        Specified by:
        visit in interface NodeTraversal.Callback
        Parameters:
        t - The current traversal.
        n - The current node.
        parent - The parent of the current node.