Update file structure

packages/contracts/test/utils/coverage.ts

@@ -0,0 +1,21 @@
+import { devConstants } from '@0xproject/dev-utils';
+import { CoverageSubprovider, SolCompilerArtifactAdapter } from '@0xproject/sol-cov';
+import * as _ from 'lodash';
+
+let coverageSubprovider: CoverageSubprovider;
+
+export const coverage = {
+    getCoverageSubproviderSingleton(): CoverageSubprovider {
+        if (_.isUndefined(coverageSubprovider)) {
+            coverageSubprovider = coverage._getCoverageSubprovider();
+        }
+        return coverageSubprovider;
+    },
+    _getCoverageSubprovider(): CoverageSubprovider {
+        const defaultFromAddress = devConstants.TESTRPC_FIRST_ADDRESS;
+        const solCompilerArtifactAdapter = new SolCompilerArtifactAdapter();
+        const isVerbose = true;
+        const subprovider = new CoverageSubprovider(solCompilerArtifactAdapter, defaultFromAddress, isVerbose);
+        return subprovider;
+    },
+};