···

       
6
       
6
       
 
       
  const path = [];

     

       
7
       
7
       
 
       
  const ancestors = [];

     

       
8
       
8
       
 
       


     

       
9
       
9
       
-
       
  function callback(node, key, parent, isLeaving) {

     

       
10
       
10
       
-
       
    const visitFn = getVisitFn(visitor, node.kind, isLeaving);

     

       
11
       
11
       
-
       
    if (visitFn) {

     

       
12
       
12
       
-
       
      const result = visitFn.call(visitor, node, key, parent, path, ancestors);

     

       
13
       
13
       
-
       
      if (result === BREAK) throw BREAK;

     

       
14
       
14
       
-
       
      return result;

     

       
15
       
15
       
-
       
    }

     

       
16
       
16
       
-
       
  }

     

       
17
       
17
       
-
       


     

       
18
       
9
       
 
       
  function traverse(node, key, parent) {

     

       
19
       
10
       
 
       
    let hasEdited = false;

     

       
20
       
11
       
 
       


     

       
21
       
21
       
-
       
    const resultEnter = callback(node, key, parent, false);

     

       
12
       
12
       
+
       
    const enter = getVisitFn(visitor, node.kind, false);

     

       
13
       
13
       
+
       
    const resultEnter =

     

       
14
       
14
       
+
       
      enter && enter.call(visitor, node, key, parent, path, ancestors);

     

       
22
       
15
       
 
       
    if (resultEnter === false) {

     

       
23
       
16
       
 
       
      return node;

     

       
24
       
17
       
 
       
    } else if (resultEnter === null) {

     

       
25
       
18
       
 
       
      return null;

     

       
19
       
19
       
+
       
    } else if (resultEnter === BREAK) {

     

       
20
       
20
       
+
       
      throw BREAK;

     

       
26
       
21
       
 
       
    } else if (resultEnter && typeof resultEnter.kind === 'string') {

     

       
27
       
22
       
 
       
      hasEdited = resultEnter !== node;

     

       
28
       
23
       
 
       
      node = resultEnter;

     
···

       
68
       
63
       
 
       
    }

     

       
69
       
64
       
 
       


     

       
70
       
65
       
 
       
    if (parent) ancestors.pop();

     

       
71
       
71
       
-
       
    const resultLeave = callback(node, key, parent, true);

     

       
72
       
72
       
-
       
    if (resultLeave !== undefined) {

     

       
66
       
66
       
+
       
    const leave = getVisitFn(visitor, node.kind, true);

     

       
67
       
67
       
+
       
    const resultLeave =

     

       
68
       
68
       
+
       
      leave && leave.call(visitor, node, key, parent, path, ancestors);

     

       
69
       
69
       
+
       
    if (resultLeave === BREAK) {

     

       
70
       
70
       
+
       
      throw BREAK;

     

       
71
       
71
       
+
       
    } else if (resultLeave !== undefined) {

     

       
73
       
72
       
 
       
      return resultLeave;

     

       
74
       
73
       
 
       
    } else if (resultEnter !== undefined) {

     

       
75
       
74
       
 
       
      return hasEdited ? copy : resultEnter;