Fix collector for DUP hashes

Author: cgewecke

lib/collector.js

@@ -27,6 +27,7 @@ class DataCollector {
     }
 
     this.lastHash = null;
+    this.viaIR = viaIR;
   }
 
   /**
@@ -39,9 +40,9 @@ class DataCollector {
       if (this.validOpcodes[info.opcode.name] && info.stack.length > 0){
         const idx = info.stack.length - 1;
         let hash = '0x' +  info.stack[idx].toString(16);
+
         this._registerHash(hash)
 
-        // console.log('hash: ' + info.opcode.name + " " + hash)
       }
     } catch (err) { /*Ignore*/ };
   }
@@ -65,15 +66,28 @@ class DataCollector {
   _registerHash(hash){
     hash = this._normalizeHash(hash);
 
-    //console.log('normalized: ' + hash);
-
     if(this.instrumentationData[hash]){
-
       // abi.encode (used to circumvent viaIR) puts the hash on the stack twice
       if (this.lastHash !== hash) {
         this.lastHash = hash;
         this.instrumentationData[hash].hits++
       }
+      return;
+    }
+
+    // Detect and recover from viaIR mangled hashes by left-padding single `0`
+    // for some cases
+    if(this.viaIR && hash.length === 18) {
+      hash = hash.slice(2);
+      hash = '0' + hash;
+      hash = hash.slice(0,16);
+      hash = '0x' + hash;
+      if(this.instrumentationData[hash]){
+        if (this.lastHash !== hash) {
+          this.lastHash = hash;
+          this.instrumentationData[hash].hits++
+        }
+      }
     }
   }
 
@@ -83,10 +97,14 @@ class DataCollector {
    * but prevents left-padding shorter irrelevant hashes
    *
    * @param  {String} hash  data hash from evm stack.
-   * @return {String}       0x prefixed hash of length 66.
+   * @return {String}       0x prefixed hash of length 18.
    */
   _normalizeHash(hash){
-    if (hash.length < 18 && hash.length > 11){
+    // viaIR sometimes zero right-pads the hashes out to 32bytes
+    // but it doesn't preserve leading zeroes when it does this
+    if (this.viaIR && hash.length >= 18) {
+      hash = hash.slice(0,18);
+    } else if (hash.length < 18 && hash.length > 11){
       hash = hash.slice(2);
       while(hash.length < 16) hash = '0' + hash;
       hash = '0x' + hash

test/integration/standard.js

@@ -364,7 +364,7 @@ describe('Hardhat Plugin: standard use cases', function() {
     verify.lineCoverage(expected);
   })
 
-  it.only('logicalOR & ternary conditionals', async function(){
+  it('logicalOR & ternary conditionals', async function(){
     mock.installFullProject('ternary-and-logical-or');
     mock.hardhatSetupEnv(this);
 

test/sources/projects/ternary-and-logical-or/test/test_or.js

@@ -5,7 +5,7 @@ contract("contract_or", function(accounts) {
 
   before(async () => instance = await Contract_OR.new())
 
-  it.only('_if', async function(){
+  it('_if', async function(){
     await instance._if(0);
     await instance._if(7);
   });