remove need of using extractValidSourceLocation

libs/remix-debug/src/solidity-decoder/internalCallTree.ts

@@ -219,20 +219,26 @@ async function buildTree (tree, step, scopeId, isExternalCall, isCreation, funct
 
   let currentSourceLocation = { start: -1, length: -1, file: -1, jump: '-' }
   let previousSourceLocation = currentSourceLocation
+  let previousValidSourceLocation = currentSourceLocation
   while (step < tree.traceManager.trace.length) {
     let sourceLocation
     let validSourceLocation
-    let newLocation = false
+    let address
     try {
-      const address = tree.traceManager.getCurrentCalledAddressAt(step)
+      address = tree.traceManager.getCurrentCalledAddressAt(step)
       sourceLocation = await tree.extractSourceLocation(step, address)
-      validSourceLocation = await tree.extractValidSourceLocation(step, address)
-
+      
       if (!includedSource(sourceLocation, currentSourceLocation)) {
         tree.reducedTrace.push(step)
         currentSourceLocation = sourceLocation
-        newLocation = true
       }
+
+      const amountOfSources = tree.sourceLocationTracker.getTotalAmountOfSources(address, tree.solidityProxy.contracts)
+      if (tree.sourceLocationTracker.isInvalidSourceLocation(currentSourceLocation, amountOfSources)) { // file is -1 or greater than amount of sources
+        validSourceLocation = previousValidSourceLocation
+      } else
+        validSourceLocation = currentSourceLocation
+    
     } catch (e) {
       return { outStep: step, error: 'InternalCallTree - Error resolving source location. ' + step + ' ' + e }
     }
@@ -261,7 +267,7 @@ async function buildTree (tree, step, scopeId, isExternalCall, isCreation, funct
       }
     }
 
-    const contractObj = await tree.solidityProxy.contractObjectAt(step)
+    const contractObj = await tree.solidityProxy.contractObjectAtAddress(address)
     const generatedSources = getGeneratedSources(tree, scopeId, contractObj)
     const functionDefinition = resolveFunctionDefinition(tree, sourceLocation, generatedSources)
 
@@ -292,6 +298,7 @@ async function buildTree (tree, step, scopeId, isExternalCall, isCreation, funct
         await includeVariableDeclaration(tree, step, sourceLocation, scopeId, contractObj, generatedSources)
       }
       previousSourceLocation = sourceLocation
+      previousValidSourceLocation = validSourceLocation
       step++
     }
   }

libs/remix-debug/src/solidity-decoder/solidityProxy.ts

@@ -47,8 +47,18 @@ export class SolidityProxy {
     * @param {Int} vmTraceIndex  - index in the vm trave where to resolve the executed contract name
     * @param {Function} cb  - callback returns (error, contractName)
     */
-  async contractObjectAt (vmTraceIndex) {
+  async contractObjectAt (vmTraceIndex: number) {
     const address = this.getCurrentCalledAddressAt(vmTraceIndex)
+    return this.contractObjectAtAddress(address)
+  }
+
+  /**
+    * retrieve the compiled contract name at the @arg vmTraceIndex (cached)
+    *
+    * @param {Int} vmTraceIndex  - index in the vm trave where to resolve the executed contract name
+    * @param {Function} cb  - callback returns (error, contractName)
+    */
+  async contractObjectAtAddress (address: string) {
     if (this.cache.contractObjectByAddress[address]) {
       return this.cache.contractObjectByAddress[address]
     }

libs/remix-debug/src/source/sourceLocationTracker.ts

@@ -87,13 +87,17 @@ export class SourceLocationTracker {
       (map.file > amountOfSources - 1) this indicates the current file index exceed the total number of files.
                                               this happens when generated sources should not be considered.
     */
-    while (vmtraceStepIndex >= 0 && (map.file === -1 || map.file > amountOfSources - 1)) {
+    while (vmtraceStepIndex >= 0 && this.isInvalidSourceLocation(map, amountOfSources)) {
       map = await this.getSourceLocationFromVMTraceIndex(address, vmtraceStepIndex, contracts)
       vmtraceStepIndex = vmtraceStepIndex - 1
     }
     return map
   }
 
+  isInvalidSourceLocation (sourceLocation, amountOfSources) {
+    return sourceLocation.file === -1 || sourceLocation.file > amountOfSources - 1
+  }
+
   async getValidSourceLocationFromVMTraceIndexFromCache (address: string, vmtraceStepIndex: number, contracts: any, cache: Map<number, any>) {
     const amountOfSources = this.getTotalAmountOfSources(address, contracts)
     let map: any = { file: -1 }