Merge pull request #330 from ethereum/gascheck

Add gas checker.

assets/css/browser-solidity.css

@@ -299,6 +299,9 @@ body {
     margin-right: 1em;
     cursor: pointer;
 }
+#staticanalysismodules label {
+    display: block;
+}
 
 #header .origin,
 #header #executionContext {

src/app/formalVerification.js

@@ -25,7 +25,10 @@ function FormalVerification (outputElement, compilerEvent) {
 
 FormalVerification.prototype.compilationFinished = function (compilationResult) {
   if (compilationResult.formal === undefined) {
-    this.event.trigger('compilationFinished', [false, 'Formal verification not supported by this compiler version.', $('#formalVerificationErrors'), true])
+    this.event.trigger(
+      'compilationFinished',
+      [false, 'Formal verification not supported by this compiler version.', $('#formalVerificationErrors'), {noAnnotations: true}]
+    )
   } else {
     if (compilationResult.formal['why3'] !== undefined) {
       $('#formalVerificationInput', this.outputElement).val(
@@ -37,10 +40,10 @@ FormalVerification.prototype.compilationFinished = function (compilationResult)
     if (compilationResult.formal.errors !== undefined) {
       var errors = compilationResult.formal.errors
       for (var i = 0; i < errors.length; i++) {
-        this.event.trigger('compilationFinished', [false, errors[i], $('#formalVerificationErrors'), true])
+        this.event.trigger('compilationFinished', [false, errors[i], $('#formalVerificationErrors'), {noAnnotations: true}])
       }
     } else {
-      this.event.trigger('compilationFinished', [true, null, null, true])
+      this.event.trigger('compilationFinished', [true, null, null, {noAnnotations: true}])
     }
   }
 }

src/app/renderer.js

@@ -11,9 +11,9 @@ function Renderer (editor, updateFiles, udapp, executionContext, formalVerificat
   this.udapp = udapp
   this.executionContext = executionContext
   var self = this
-  formalVerificationEvent.register('compilationFinished', this, function (success, message, container, noAnnotations) {
+  formalVerificationEvent.register('compilationFinished', this, function (success, message, container, options) {
     if (!success) {
-      self.error(message, container, noAnnotations)
+      self.error(message, container, options)
     }
   })
   compilerEvent.register('compilationFinished', this, function (success, data, source) {
@@ -34,13 +34,19 @@ function Renderer (editor, updateFiles, udapp, executionContext, formalVerificat
   })
 }
 
-Renderer.prototype.error = function (message, container, noAnnotations, type) {
+Renderer.prototype.error = function (message, container, options) {
   var self = this
-  if (!type) {
+  var opt = options || {}
-    type = utils.errortype(message)
+  if (!opt.type) {
+    opt.type = utils.errortype(message)
   }
-  var $pre = $('<pre />').text(message)
+  var $pre
-  var $error = $('<div class="sol ' + type + '"><div class="close"><i class="fa fa-close"></i></div></div>').prepend($pre)
+  if (opt.isHTML) {
+    $pre = $(opt.useSpan ? '<span />' : '<pre />').html(message)
+  } else {
+    $pre = $(opt.useSpan ? '<span />' : '<pre />').text(message)
+  }
+  var $error = $('<div class="sol ' + opt.type + '"><div class="close"><i class="fa fa-close"></i></div></div>').prepend($pre)
   if (container === undefined) {
     container = $('#output')
   }
@@ -50,12 +56,12 @@ Renderer.prototype.error = function (message, container, noAnnotations, type) {
     var errFile = err[1]
     var errLine = parseInt(err[2], 10) - 1
     var errCol = err[4] ? parseInt(err[4], 10) : 0
-    if (!noAnnotations && (errFile === '' || errFile === utils.fileNameFromKey(self.editor.getCacheFile()))) {
+    if (!opt.noAnnotations && (errFile === '' || errFile === utils.fileNameFromKey(self.editor.getCacheFile()))) {
       self.editor.addAnnotation({
         row: errLine,
         column: errCol,
         text: message,
-        type: type
+        type: opt.type
       })
     }
     $error.click(function (ev) {
@@ -63,7 +69,6 @@ Renderer.prototype.error = function (message, container, noAnnotations, type) {
         // Switch to file
         self.editor.setCacheFile(utils.fileKey(errFile))
         self.updateFiles()
-      // @TODO could show some error icon in files with errors
       }
       self.editor.handleErrorClick(errLine, errCol)
     })

src/app/staticanalysis/modules/gasCosts.js

@@ -0,0 +1,50 @@
+var name = 'gas costs'
+var desc = 'Warn if the gas requiremets of functions are too high.'
+
+function gasCosts () {
+}
+
+gasCosts.prototype.report = function (compilationResults) {
+  var report = []
+  for (var contractName in compilationResults.contracts) {
+    var contract = compilationResults.contracts[contractName]
+    if (
+      contract.gasEstimates === undefined ||
+      contract.gasEstimates.external === undefined
+    ) {
+      continue
+    }
+    var fallback = contract.gasEstimates.external['']
+    if (fallback !== undefined) {
+      if (fallback === null || fallback >= 2100) {
+        report.push({
+          warning: `Fallback function of contract ${contractName} requires too much gas (${fallback}).<br />
+          If the fallback function requires more than 2300 gas, the contract cannot receive Ether.`
+        })
+      }
+    }
+
+    for (var functionName in contract.gasEstimates.external) {
+      if (functionName === '') {
+        continue
+      }
+      var gas = contract.gasEstimates.external[functionName]
+      var gasString = gas === null ? 'unknown or not constant' : 'high: ' + gas
+      if (gas === null || gas >= 3000000) {
+        report.push({
+          warning: `Gas requirement of function ${contractName}.${functionName} ${gasString}.<br />
+          If the gas requirement of a function is higher than the block gas limit, it cannot be executed.
+          Please avoid loops in your functions or actions that modify large areas of storage
+          (this includes clearing or copying arrays in storage)`
+        })
+      }
+    }
+  }
+  return report
+}
+
+module.exports = {
+  name: name,
+  description: desc,
+  Module: gasCosts
+}

src/app/staticanalysis/modules/list.js

@@ -1,3 +1,4 @@
 module.exports = [
-  require('./txOrigin')
+  require('./txOrigin'),
+  require('./gasCosts')
 ]

src/app/staticanalysis/modules/txOrigin.js

@@ -2,7 +2,7 @@ var name = 'tx origin'
 var desc = 'warn if tx.origin is used'
 
 function txOrigin () {
-  this.txOriginNode = []
+  this.txOriginNodes = []
 }
 
 txOrigin.prototype.visit = function (node) {
@@ -12,23 +12,18 @@ txOrigin.prototype.visit = function (node) {
   node.children && node.children.length &&
   node.children[0].attributes.type === 'tx' &&
   node.children[0].attributes.value === 'tx') {
-    this.txOriginNode.push(node)
+    this.txOriginNodes.push(node)
   }
 }
 
-txOrigin.prototype.report = function (node) {
+txOrigin.prototype.report = function () {
-  var report = []
+  return this.txOriginNodes.map(function (item, i) {
-  this.txOriginNode.map(function (item, i) {
+    return {
-    report.push({
+      warning: `use of tx.origin: "tx.origin" is useful only in very exceptional cases.<br />
-      warning: `use of tx.origin: "tx.origin" is useful only in very exceptional cases.\n
                 If you use it for authentication, you usually want to replace it by "msg.sender", because otherwise any contract you call can act on your behalf.`,
       location: item.src
-    })
+    }
   })
-  return {
-    name: name,
-    report: report
-  }
 }
 
 module.exports = {

src/app/staticanalysis/staticAnalysisRunner.js

@@ -5,20 +5,30 @@ var list = require('./modules/list')
 function staticAnalysisRunner () {
 }
 
-staticAnalysisRunner.prototype.run = function (ast, toRun, callback) {
+staticAnalysisRunner.prototype.run = function (compilationResult, toRun, callback) {
+  var self = this
+  var modules = toRun.map(function (i) {
+    var m = self.modules()[i]
+    return { 'name': m.name, 'mod': new m.Module() }
+  })
+
+  // Also provide convenience analysis via the AST walker.
   var walker = new AstWalker()
-  for (var k in ast) {
+  for (var k in compilationResult.sources) {
-    walker.walk(ast[k].AST, {'*': function (node) {
+    walker.walk(compilationResult.sources[k].AST, {'*': function (node) {
-      toRun.map(function (item, i) {
+      modules.map(function (item, i) {
-        item.visit(node)
+        if (item.mod.visit !== undefined) {
+          item.mod.visit(node)
+        }
       })
       return true
     }})
   }
 
-  var reports = []
+  // Here, modules can just collect the results from the AST walk,
-  toRun.map(function (item, i) {
+  // but also perform new analysis.
-    reports.push(item.report())
+  var reports = modules.map(function (item, i) {
+    return { name: item.name, report: item.mod.report(compilationResult) }
   })
   callback(reports)
 }

src/app/staticanalysis/staticAnalysisView.js

@@ -28,8 +28,10 @@ staticAnalysisView.prototype.render = function () {
   var self = this
   var view = yo`<div>
     <strong>Static Analysis</strong>
-    <div>Select analyser to run against current compiled contracts <label><input id="autorunstaticanalysis" type="checkbox" checked="true">Auto run Static Analysis</label></div>    
+    <label for="autorunstaticanalysis"><input id="autorunstaticanalysis" type="checkbox" checked="true">Auto run</label>
+    <div id="staticanalysismodules">
     ${this.modulesView}
+    </div>
     <div>
       <button onclick=${function () { self.run() }} >Run</button>
     </div>
@@ -45,14 +47,10 @@ staticAnalysisView.prototype.selectedModules = function () {
   if (!this.view) {
     return []
   }
-  var selected = this.view.querySelectorAll('[name="staticanalysismodule"]')
+  var selected = this.view.querySelectorAll('[name="staticanalysismodule"]:checked')
   var toRun = []
   for (var i = 0; i < selected.length; i++) {
-    var el = selected[i]
+    toRun.push(selected[i].attributes['index'].value)
-    if (el.checked) {
-      var analyser = this.runner.modules()[el.attributes['index'].value]
-      toRun.push(new analyser.Module())
-    }
   }
   return toRun
 }
@@ -66,18 +64,21 @@ staticAnalysisView.prototype.run = function () {
   warningContainer.empty()
   if (this.lastCompilationResult) {
     var self = this
-    this.runner.run(this.lastCompilationResult.sources, selected, function (results) {
+    this.runner.run(this.lastCompilationResult, selected, function (results) {
       results.map(function (result, i) {
         result.report.map(function (item, i) {
-          var split = item.location.split(':')
+          var location = ''
-          var file = split[2]
+          if (item.location !== undefined) {
-          var location = {
+            var split = item.location.split(':')
-            start: parseInt(split[0]),
+            var file = split[2]
-            length: parseInt(split[1])
+            location = {
+              start: parseInt(split[0]),
+              length: parseInt(split[1])
+            }
+            location = self.offsetToColumnConverter.offsetToLineColumn(location, file, self.editor, self.lastCompilationResult)
+            location = self.lastCompilationResult.sourceList[file] + ':' + (location.start.line + 1) + ':' + (location.start.column + 1) + ':'
           }
-          location = self.offsetToColumnConverter.offsetToLineColumn(location, file, self.editor, self.lastCompilationResult)
+          self.renderer.error(location + ' ' + item.warning, warningContainer, {type: 'warning', useSpan: true, isHTML: true})
-          location = self.lastCompilationResult.sourceList[file] + ':' + (location.start.line + 1) + ':' + (location.start.column + 1) + ':'
-          self.renderer.error(location + ' ' + item.warning, warningContainer, false, 'warning')
         })
       })
       if (warningContainer.html() === '') {

test-browser/helpers/contracts.js

@@ -21,6 +21,7 @@ function testContracts (browser, contractCode, compiledContractNames, callback)
       .clearValue('#input textarea')
       .click('.newFile')
       .setValue('#input textarea', contractCode, function () {})
-      .waitForElementPresent('.contract .create', 2000)
+      .waitForElementPresent('.contract .create', 2000, true, function () {
-  checkCompiledContracts(browser, compiledContractNames, callback)
+        checkCompiledContracts(browser, compiledContractNames, callback)
+      })
 }

test-browser/helpers/dom.js

@@ -0,0 +1,20 @@
+'use strict'
+
+module.exports = {
+  listSelectorContains: listSelectorContains
+}
+
+function listSelectorContains (textsToFind, selector, browser, callback) {
+  browser
+    .elements('css selector', selector, function (warnings) {
+      warnings.value.map(function (warning, index) {
+        browser.elementIdText(warning.ELEMENT, function (text) {
+          browser.assert.equal(text.value.indexOf(textsToFind[index]) !== -1, true)
+          if (index === warnings.value.length - 1) {
+            callback()
+          }
+        })
+      })
+    })
+}
+

test-browser/tests/staticanalysis.js

@@ -2,10 +2,17 @@
 var contractHelper = require('../helpers/contracts')
 var init = require('../helpers/init')
 var sauce = require('./sauce')
+var dom = require('../helpers/dom')
 
 var sources = {
   'sources': {
-    'Untitled': `contract test1 { address test = tx.origin; } contract test2 {}`
+    'Untitled': `
+contract test1 { address test = tx.origin; }
+contract test2 {}
+contract TooMuchGas {
+  uint x;
+  function() { x++; }
+}`
   }
 }
 
@@ -25,12 +32,18 @@ module.exports = {
 function runTests (browser) {
   browser
     .waitForElementVisible('.newFile', 10000)
-  contractHelper.testContracts(browser, sources.sources.Untitled, ['test1', 'test2'], function () {
+  contractHelper.testContracts(browser, sources.sources.Untitled, ['TooMuchGas', 'test1', 'test2'], function () {
     browser
-    .click('.staticanalysisView')
+      .click('.staticanalysisView')
-    .click('#staticanalysisView button')
+      .click('#staticanalysisView button')
-    .waitForElementPresent('#staticanalysisresult .warning')
+      .waitForElementPresent('#staticanalysisresult .warning', 2000, true, function () {
-    .assert.containsText('#staticanalysisresult .warning pre', 'Untitled:1:33: use of tx.origin')
+        dom.listSelectorContains(['Untitled:1:34: use of tx.origin',
-    .end()
+          'Fallback function of contract TooMuchGas requires too much gas'],
+          '#staticanalysisresult .warning span',
+          browser, function () {
+            browser.end()
+          }
+        )
+      })
   })
 }