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@babel/traverse noScope can't path.remove()

See original GitHub issue

When I upgraded from v7.7.7 to v7.8.4, I found that there was a problem with the noScope option of @babel/traverse.

Error message:

e:\mypath\babel\node_modules\@babel\traverse\lib\path\removal.js:39
  Object.keys(bindings).forEach(name => this.scope.removeBinding(name));
                                                   ^

TypeError: Cannot read property 'removeBinding' of null
    at e:\mypath\babel\node_modules\@babel\traverse\lib\path\removal.js:39:52
    at Array.forEach (<anonymous>)
    at NodePath._removeFromScope (e:\mypath\babel\node_modules\@babel\traverse\lib\path\removal.js:39:25)
    at NodePath.remove (e:\mypath\babel\node_modules\@babel\traverse\lib\path\removal.js:22:8)
    at AssignmentExpression (e:\mypath\babel\test.js:6:14)
    at NodePath._call (e:\mypath\babel\node_modules\@babel\traverse\lib\path\context.js:55:20)
    at NodePath.call (e:\mypath\babel\node_modules\@babel\traverse\lib\path\context.js:42:17)
    at NodePath.visit (e:\mypath\babel\node_modules\@babel\traverse\lib\path\context.js:90:31)
    at TraversalContext.visitQueue (e:\mypath\babel\node_modules\@babel\traverse\lib\context.js:112:16)
    at TraversalContext.visitSingle (e:\mypath\babel\node_modules\@babel\traverse\lib\context.js:84:19)

Code to reproduce the problem:

var traverse = require("@babel/traverse").default;
var parser = require("@babel/parser");

traverse(parser.parse("a=1"), {
    AssignmentExpression(path) {
        path.remove();
    },
    noScope: true,
});