3 files changed, 11 insertions, 2 deletions
diff --git a/packages/sol-cov/src/collect_coverage_entries.ts b/packages/sol-cov/src/collect_coverage_entries.ts
index b145f044e..3fc85008c 100644
--- a/packages/sol-cov/src/collect_coverage_entries.ts
+++ b/packages/sol-cov/src/collect_coverage_entries.ts
@@ -10,7 +10,7 @@ const coverageEntriesBySourceHash: { [sourceHash: string]: CoverageEntriesDescri
 
 export const collectCoverageEntries = (contractSource: string) => {
     const sourceHash = ethUtil.sha3(contractSource).toString('hex');
-    if (_.isUndefined(coverageEntriesBySourceHash[sourceHash])) {
+    if (_.isUndefined(coverageEntriesBySourceHash[sourceHash]) && !_.isUndefined(contractSource)) {
         const ast = parser.parse(contractSource, { range: true });
         const locationByOffset = getLocationByOffset(contractSource);
         const visitor = new ASTVisitor(locationByOffset);
diff --git a/packages/sol-cov/src/coverage_subprovider.ts b/packages/sol-cov/src/coverage_subprovider.ts
index 0fa7f873e..2f0bcbb93 100644
--- a/packages/sol-cov/src/coverage_subprovider.ts
+++ b/packages/sol-cov/src/coverage_subprovider.ts
@@ -66,6 +66,12 @@ export const coverageHandler: SingleFileSubtraceHandler = (
 ): Coverage => {
     const absoluteFileName = contractData.sources[fileIndex];
     const coverageEntriesDescription = collectCoverageEntries(contractData.sourceCodes[fileIndex]);
+
+    // if the source wasn't provided for the fileIndex, we can't cover the file
+    if (_.isUndefined(coverageEntriesDescription)) {
+        return {};
+    }
+
     let sourceRanges = _.map(subtrace, structLog => pcToSourceRange[structLog.pc]);
     sourceRanges = _.compact(sourceRanges); // Some PC's don't map to a source range and we just ignore them.
     // By default lodash does a shallow object comparasion. We JSON.stringify them and compare as strings.
diff --git a/packages/sol-cov/src/source_maps.ts b/packages/sol-cov/src/source_maps.ts
index f9503e16c..c95c7d2b0 100644
--- a/packages/sol-cov/src/source_maps.ts
+++ b/packages/sol-cov/src/source_maps.ts
@@ -12,6 +12,9 @@ export interface SourceLocation {
 }
 
 export function getLocationByOffset(str: string): LocationByOffset {
+    if (_.isUndefined(str)) {
+        return {};
+    }
     const locationByOffset: LocationByOffset = { 0: { line: 1, column: 0 } };
     let currentOffset = 0;
     for (const char of str.split('')) {
@@ -56,7 +59,7 @@ export function parseSourceMap(
             length,
             fileIndex,
         };
-        if (parsedEntry.fileIndex !== -1) {
+        if (parsedEntry.fileIndex !== -1 && !_.isUndefined(locationByOffsetByFileIndex[parsedEntry.fileIndex])) {
             const sourceRange = {
                 location: {
                     start: locationByOffsetByFileIndex[parsedEntry.fileIndex][parsedEntry.offset],