Fix a bug when TruffleArtifactAdapter was incorrectly parsing the truffle config of the newest version

packages/sol-tracing-utils/CHANGELOG.json

@@ -1,4 +1,13 @@
 [
+    {
+        "version": "6.0.6",
+        "changes": [
+            {
+                "note": "Fix a bug when `TruffleArtifactAdapter` wasn't parsing solc config in the newest version of trufle",
+                "pr": 1654
+            }
+        ]
+    },
     {
         "timestamp": 1551220833,
         "version": "6.0.5",

packages/sol-tracing-utils/package.json

@@ -55,6 +55,7 @@
         "ethereumjs-util": "^5.1.1",
         "ethers": "~4.0.4",
         "glob": "^7.1.2",
+        "solc": "^0.5.2",
         "istanbul": "^0.4.5",
         "lodash": "^4.17.11",
         "loglevel": "^1.6.1",

packages/sol-tracing-utils/src/artifact_adapters/truffle_artifact_adapter.ts

@@ -1,7 +1,9 @@
 import { Compiler, CompilerOptions } from '@0x/sol-compiler';
 import * as fs from 'fs';
 import * as glob from 'glob';
+import * as _ from 'lodash';
 import * as path from 'path';
+import * as solc from 'solc';
 
 import { ContractData } from '../types';
 
@@ -10,8 +12,15 @@ import { SolCompilerArtifactAdapter } from './sol_compiler_artifact_adapter';
 
 const DEFAULT_TRUFFLE_ARTIFACTS_DIR = './build/contracts';
 
+interface TruffleSolcConfig {
+    version?: string;
+    settings?: solc.CompilerSettings;
+}
 interface TruffleConfig {
-    solc?: any;
+    solc?: TruffleSolcConfig;
+    compilers?: {
+        solc?: TruffleSolcConfig;
+    };
     contracts_build_directory?: string;
 }
 
@@ -32,7 +41,7 @@ export class TruffleArtifactAdapter extends AbstractArtifactAdapter {
         const artifactsDir = '.0x-artifacts';
         const contractsDir = path.join(this._projectRoot, 'contracts');
         const truffleConfig = this._getTruffleConfig();
-        const solcConfig = truffleConfig.solc || {};
+        const solcConfig = this._getTruffleSolcSettings();
         const truffleArtifactsDirectory = truffleConfig.contracts_build_directory || DEFAULT_TRUFFLE_ARTIFACTS_DIR;
         this._assertSolidityVersionIsCorrect(truffleArtifactsDirectory);
         const compilerOptions: CompilerOptions = {
@@ -70,6 +79,18 @@ export class TruffleArtifactAdapter extends AbstractArtifactAdapter {
             );
         }
     }
+    private _getTruffleSolcSettings(): Partial<solc.CompilerSettings> {
+        const truffleConfig = this._getTruffleConfig();
+        if (!_.isUndefined(truffleConfig.solc)) {
+            // Truffle < 5.0
+            return (truffleConfig as any).solc.settings;
+        } else if (!_.isUndefined((truffleConfig as any).compilers.solc)) {
+            // Truffle >= 5.0
+            return (truffleConfig as any).compilers.solc.settings;
+        } else {
+            return {};
+        }
+    }
     private _assertSolidityVersionIsCorrect(truffleArtifactsDirectory: string): void {
         const artifactsGlob = `${truffleArtifactsDirectory}/**/*.json`;
         const artifactFileNames = glob.sync(artifactsGlob, { absolute: true });