Merge pull request #81 from yann300/astCrawler

Ast Crawler

src/index.js

@@ -5,6 +5,7 @@ var BasicPanel = require('./ui/BasicPanel')
 var TraceManager = require('./trace/traceManager')
 var CodeManager = require('./code/codeManager')
 var SourceMappingDecoder = require('./util/sourceMappingDecoder')
+var AstWalker = require('./util/astWalker')
 
 if (typeof (module) !== 'undefined' && typeof (module.exports) !== 'undefined') {
   module.exports = modules()
@@ -24,7 +25,8 @@ function modules () {
       BasicPanel: BasicPanel
     },
     util: {
-      SourceMappingDecoder: SourceMappingDecoder
+      SourceMappingDecoder: SourceMappingDecoder,
+      AstWalker: AstWalker
     }
   }
 }

src/util/astWalker.js

@@ -0,0 +1,41 @@
+'use strict'
+/**
+ * Crawl the given AST through the function walk(ast, callback)
+ */
+function AstWalker () {
+}
+
+/**
+ * visit all the AST nodes
+ *
+ * @param {Object} ast  - AST node
+ * @param {Object or Function} callback  - if (Function) the function will be called for every node.
+ *                                       - if (Object) callback[<Node Type>] will be called for
+ *                                         every node of type <Node Type>. callback["*"] will be called fo all other nodes.
+ *                                         in each case, if the callback returns false it does not descend into children.
+ *                                         If no callback for the current type, children are visited.
+ */
+AstWalker.prototype.walk = function (ast, callback) {
+  if (callback instanceof Function) {
+    callback = {'*': callback}
+  }
+  if (!('*' in callback)) {
+    callback['*'] = function () { return true }
+  }
+  if (manageCallBack(ast, callback) && ast.children && ast.children.length > 0) {
+    for (var k in ast.children) {
+      var child = ast.children[k]
+      this.walk(child, callback)
+    }
+  }
+}
+
+function manageCallBack (node, callback) {
+  if (node.name in callback) {
+    return callback[node.name](node)
+  } else {
+    return callback['*'](node)
+  }
+}
+
+module.exports = AstWalker

test/astwalker.js

@@ -0,0 +1,61 @@
+'use strict'
+var tape = require('tape')
+var AstWalker = require('../src/util/astWalker')
+var node = require('./resources/ast')
+
+tape('ASTWalker', function (t) {
+  t.test('ASTWalker.walk', function (st) {
+    st.plan(24)
+    var astwalker = new AstWalker()
+
+    astwalker.walk(node.ast.AST, function (node) {
+      if (node.name === 'ContractDefinition') {
+        checkContract(st, node)
+      }
+      if (node.name === 'FunctionDefinition') {
+        checkSetFunction(st, node)
+      }
+      return true
+    })
+
+    var callback = {}
+    callback.FunctionDefinition = function (node) {
+      st.equal(node.name, 'FunctionDefinition')
+      st.equal(node.attributes.name === 'set' || node.attributes.name === 'get', true)
+      return true
+    }
+    astwalker.walk(node.ast.AST, callback)
+  })
+})
+
+function checkContract (st, node) {
+  st.equal(node.attributes.name, 'test')
+  st.equal(node.children[0].attributes.name, 'x')
+  st.equal(node.children[0].attributes.type, 'int256')
+  st.equal(node.children[1].attributes.name, 'y')
+  st.equal(node.children[1].attributes.type, 'int256')
+  st.equal(node.children[2].name, 'FunctionDefinition')
+  st.equal(node.children[2].attributes.constant, false)
+  st.equal(node.children[2].attributes.name, 'set')
+  st.equal(node.children[2].attributes.public, true)
+}
+
+function checkSetFunction (st, node) {
+  if (node.attributes.name === 'set') {
+    st.equal(node.children[0].name, 'ParameterList')
+    st.equal(node.children[1].name, 'ParameterList')
+    st.equal(node.children[2].name, 'Block')
+    st.equal(node.children[2].children[1].name, 'ExpressionStatement')
+    checkExpressionStatement(st, node.children[2].children[0])
+  }
+}
+
+function checkExpressionStatement (st, node) {
+  st.equal(node.children[0].name, 'Assignment')
+  st.equal(node.children[0].attributes.operator, '=')
+  st.equal(node.children[0].attributes.type, 'int256')
+  st.equal(node.children[0].children[0].name, 'Identifier')
+  st.equal(node.children[0].children[0].attributes.value, 'x')
+  st.equal(node.children[0].children[1].name, 'Identifier')
+  st.equal(node.children[0].children[1].attributes.value, '_x')
+}

test/resources/ast.js

@@ -0,0 +1,23 @@
+var node = {}
+
+node.ast = {"AST":{"children":[{"attributes":{"fullyImplemented":true,"isLibrary":false,"linearizedBaseContracts":[5640396],"name":"test"},"children":[{"attributes":{"name":"x","type":"int256"},"children":[{"attributes":{"name":"int"},"id":5657860,"name":"ElementaryTypeName","src":"21:3:11"}],"id":5658100,"name":"VariableDeclaration","src":"21:5:11"},{"attributes":{"name":"y","type":"int256"},"children":[{"attributes":{"name":"int"},"id":5658180,"name":"ElementaryTypeName","src":"38:3:11"}],"id":5658268,"name":"VariableDeclaration","src":"38:5:11"},{"attributes":{"constant":false,"name":"set","public":true},"children":[{"children":[{"attributes":{"name":"_x","type":"int256"},"children":[{"attributes":{"name":"int"},"id":5658404,"name":"ElementaryTypeName","src":"68:3:11"}],"id":5658492,"name":"VariableDeclaration","src":"68:6:11"}],"id":5658572,"name":"ParameterList","src":"67:8:11"},{"children":[{"attributes":{"name":"_r","type":"int256"},"children":[{"attributes":{"name":"int"},"id":5658628,"name":"ElementaryTypeName","src":"85:3:11"}],"id":5658716,"name":"VariableDeclaration","src":"85:6:11"}],"id":5658796,"name":"ParameterList","src":"84:8:11"},{"children":[{"children":[{"attributes":{"operator":"=","type":"int256"},"children":[{"attributes":{"type":"int256","value":"x"},"id":5658900,"name":"Identifier","src":"108:1:11"},{"attributes":{"type":"int256","value":"_x"},"id":5658980,"name":"Identifier","src":"112:2:11"}],"id":5657492,"name":"Assignment","src":"108:6:11"}],"id":5659028,"name":"ExpressionStatement","src":"108:6:11"},{"children":[{"attributes":{"operator":"=","type":"int256"},"children":[{"attributes":{"type":"int256","value":"y"},"id":5659116,"name":"Identifier","src":"125:1:11"},{"attributes":{"string":null,"type":"int_const 10","value":"10"},"id":5659196,"name":"Literal","src":"129:2:11"}],"id":5659252,"name":"Assignment","src":"125:6:11"}],"id":5659316,"name":"ExpressionStatement","src":"125:6:11"},{"children":[{"attributes":{"operator":"=","type":"int256"},"children":[{"attributes":{"type":"int256","value":"_r"},"id":5659428,"name":"Identifier","src":"141:2:11"},{"attributes":{"type":"int256","value":"x"},"id":5639308,"name":"Identifier","src":"146:1:11"}],"id":5639356,"name":"Assignment","src":"141:6:11"}],"id":5639420,"name":"ExpressionStatement","src":"141:6:11"}],"id":5639516,"name":"Block","src":"97:57:11"}],"id":5639612,"name":"FunctionDefinition","src":"55:99:11"},{"attributes":{"constant":false,"name":"get","public":true},"children":[{"children":[],"id":5639764,"name":"ParameterList","src":"179:2:11"},{"children":[{"attributes":{"name":"x","type":"uint256"},"children":[{"attributes":{"name":"uint"},"id":5639820,"name":"ElementaryTypeName","src":"191:4:11"}],"id":5639908,"name":"VariableDeclaration","src":"191:6:11"},{"attributes":{"name":"y","type":"uint256"},"children":[{"attributes":{"name":"uint"},"id":5639988,"name":"ElementaryTypeName","src":"199:4:11"}],"id":5640076,"name":"VariableDeclaration","src":"199:6:11"}],"id":5640156,"name":"ParameterList","src":"190:16:11"},{"children":[],"id":5640212,"name":"Block","src":"212:17:11"}],"id":5640276,"name":"FunctionDefinition","src":"167:62:11"}],"id":5640396,"name":"ContractDefinition","src":"0:231:11"}],"name":"SourceUnit"}}
+
+node.source = `contract test { 
+    int x; 
+    
+    int y; 
+    
+    function set(int _x) returns (int _r)
+    { 
+        x = _x; 
+        y = 10;
+        _r = x;
+    } 
+      
+    function get() returns (uint x, uint y) 
+    {
+         
+    }
+}`
+
+module.exports = node

test/tests.js

@@ -3,3 +3,5 @@ require('./index.js')
 require('./traceManager.js')
 require('./codeManager.js')
 require('./util.js')
+require('./astwalker.js')
+