Add a HACK to detect coverage of the modifiers with no parameters

packages/sol-cov/src/ast_visitor.ts

@@ -7,6 +7,7 @@ export interface CoverageEntriesDescription {
     fnMap: FnMap;
     branchMap: BranchMap;
     statementMap: StatementMap;
+    modifiersStatementIds: number[];
 }
 
 enum BranchType {
@@ -19,6 +20,7 @@ export class ASTVisitor {
     private _entryId = 0;
     private _fnMap: FnMap = {};
     private _branchMap: BranchMap = {};
+    private _modifiersStatementIds: number[] = [];
     private _statementMap: StatementMap = {};
     private _locationByOffset: LocationByOffset;
     private static _doesLookLikeAnASTNode(ast: any): boolean {
@@ -49,6 +51,7 @@ export class ASTVisitor {
             fnMap: this._fnMap,
             branchMap: this._branchMap,
             statementMap: this._statementMap,
+            modifiersStatementIds: this._modifiersStatementIds,
         };
         return coverageEntriesDescription;
     }
@@ -91,6 +94,7 @@ export class ASTVisitor {
     private _visitModifierArgument(ast: SolidityParser.AST): void {
         const BUILTIN_MODIFIERS = ['public', 'view', 'payable', 'external', 'internal', 'pure', 'constant'];
         if (!_.includes(BUILTIN_MODIFIERS, ast.name)) {
+            this._modifiersStatementIds.push(this._entryId);
             this._visitStatement(ast);
         }
     }

packages/sol-cov/src/coverage_manager.ts

@@ -69,6 +69,30 @@ export class CoverageManager {
             );
             functionCoverage[fnId] = isCovered;
         }
+        // HACK: Solidity doesn't emit any opcodes that map back to modifiers with no args, that's why we map back to the
+        // function range and check if there is any covered statement within that range.
+        for (const modifierStatementId of coverageEntriesDescription.modifiersStatementIds) {
+            if (statementCoverage[modifierStatementId]) {
+                // Already detected as covered
+                continue;
+            }
+            const modifierDescription = coverageEntriesDescription.statementMap[modifierStatementId];
+            const enclosingFunction = _.find(coverageEntriesDescription.fnMap, functionDescription =>
+                utils.isRangeInside(modifierDescription, functionDescription.loc),
+            ) as FunctionDescription;
+            const isModifierCovered = _.some(
+                coverageEntriesDescription.statementMap,
+                (statementDescription: StatementDescription, statementId: number) => {
+                    const isInsideTheModifierEnclosingFunction = utils.isRangeInside(
+                        statementDescription,
+                        enclosingFunction.loc,
+                    );
+                    const isCovered = statementCoverage[statementId];
+                    return isInsideTheModifierEnclosingFunction && isCovered;
+                },
+            );
+            statementCoverage[modifierStatementId] = isModifierCovered;
+        }
         const partialCoverage = {
             [contractData.sources[fileIndex]]: {
                 ...coverageEntriesDescription,