From c27ed7245f34e8ca4edac7c6f55e0b82c60f9a7a Mon Sep 17 00:00:00 2001
From: aniket-engg <aniketengg.225@gmail.com>
Date: Fri, 15 May 2020 00:49:19 +0530
Subject: [PATCH] gas costs analysis for public state variable

---
 .../src/solidity-analyzer/modules/gasCosts.ts | 60 ++++++++++---------
 1 file changed, 31 insertions(+), 29 deletions(-)

diff --git a/remix-analyzer/src/solidity-analyzer/modules/gasCosts.ts b/remix-analyzer/src/solidity-analyzer/modules/gasCosts.ts
index 2d0feda0d9..7e9eb10a85 100644
--- a/remix-analyzer/src/solidity-analyzer/modules/gasCosts.ts
+++ b/remix-analyzer/src/solidity-analyzer/modules/gasCosts.ts
@@ -1,7 +1,7 @@
 import { default as category } from './categories'
 import { default as algorithm } from './algorithmCategories'
 import { getFunctionDefinitionName, helpers, getType } from './staticAnalysisCommon'
-import { ModuleAlgorithm, ModuleCategory, ReportObj, CompilationResult, CompiledContractObj, CompiledContract, VisitFunction, AnalyzerModule, FunctionDefinitionAstNode} from './../../types'
+import { ModuleAlgorithm, ModuleCategory, ReportObj, CompilationResult, CompiledContractObj, CompiledContract, VisitFunction, AnalyzerModule, FunctionDefinitionAstNode, YulVariableDeclarationAstNode, VariableDeclarationAstNode} from './../../types'
 
 interface VisitedContract {
   name: string
@@ -15,26 +15,34 @@ export default class gasCosts implements AnalyzerModule {
   category: ModuleCategory = category.GAS
   algorithm: ModuleAlgorithm = algorithm.EXACT
 
-  warningNodes: FunctionDefinitionAstNode[] = []
-  visit (node: FunctionDefinitionAstNode): void {
-    if (node.nodeType === 'FunctionDefinition' && node.kind !== 'constructor') this.warningNodes.push(node)
+  warningNodes: any[] = []
+  visit (node: FunctionDefinitionAstNode | VariableDeclarationAstNode): void {
+    if ((node.nodeType === 'FunctionDefinition' && node.kind !== 'constructor' && node.implemented) || 
+    (node.nodeType === 'VariableDeclaration' && node.stateVariable && node.visibility === 'public')) 
+      this.warningNodes.push(node)
   }
   
   report (compilationResults: CompilationResult): ReportObj[] {
     const report: ReportObj[] = []
 
     const methodsWithSignature =  this.warningNodes.map(node => {
+      let signature;
+      if(node.nodeType === 'FunctionDefinition')
+        signature = helpers.buildAbiSignature(getFunctionDefinitionName(node), node.parameters.parameters.map(node => node.typeDescriptions.typeString.split(' ')[0]))
+      else 
+        signature = node.name + '()'
+      
       return {
         name: node.name,
         src: node.src,
-        signature: helpers.buildAbiSignature(getFunctionDefinitionName(node), node.parameters.parameters.map(node => node.typeDescriptions.typeString.split(' ')[0]))
+        signature: signature
       }
     })
     for (const method of methodsWithSignature) {
       for (const contractName in compilationResults.contracts['test.sol']) {
         const contract = compilationResults.contracts['test.sol'][contractName]
         const methodGas: any = this.checkMethodGas(contract, method.signature)
-        if(methodGas.isInfinite) {
+        if(methodGas && methodGas.isInfinite) {
           if(methodGas.isFallback) {
             report.push({
               warning: `Fallback function of contract ${contractName} requires too much gas (${methodGas.msg}). 
@@ -48,38 +56,32 @@ export default class gasCosts implements AnalyzerModule {
               (this includes clearing or copying arrays in storage)`
             })
           } 
-        }
+        } else continue
       }
     }
     return report
   }
 
   private checkMethodGas(contract: any, methodSignature: string) {
-    if(methodSignature === '()') {
-      const fallback: string = contract.evm.gasEstimates.external['']
-        if (fallback !== undefined && (fallback === null || parseInt(fallback) >= 2100 || fallback === 'infinite')) {
+    if(contract.evm && contract.evm.gasEstimates && contract.evm.gasEstimates.external) {
+      if(methodSignature === '()') {
+        const fallback: string = contract.evm.gasEstimates.external['']
+          if (fallback !== undefined && (fallback === null || parseInt(fallback) >= 2100 || fallback === 'infinite')) {
+            return {
+              isInfinite: true,
+              isFallback: true,
+              msg: fallback
+            }
+          } 
+      } else {
+        const gas: string = contract.evm.gasEstimates.external[methodSignature]
+        const gasString: string = gas === null ? 'unknown or not constant' : 'high: ' + gas
+        if (gas === null || parseInt(gas) >= 3000000 || gas === 'infinite') {
           return {
             isInfinite: true,
-            isFallback: true,
-            msg: fallback
+            msg: gasString
           }
-        } else {
-          return {
-            isInfinite: false
-          }
-        }
-    } else {
-      const gas: string = contract.evm.gasEstimates.external[methodSignature]
-      const gasString: string = gas === null ? 'unknown or not constant' : 'high: ' + gas
-      if (gas === null || parseInt(gas) >= 3000000 || gas === 'infinite') {
-        return {
-          isInfinite: true,
-          msg: gasString
-        }
-      } else {
-        return {
-          isInfinite: false
-        }
+        } 
       }
     }
   }