Fix the undefined opts bug

packages/sol-compiler/CHANGELOG.json

@@ -5,6 +5,10 @@
             {
                 "note": "Fix a bug when smart recompilation wasn't working because of remappings",
                 "pr": 1575
+            },
+            {
+                "note": "Fix a bug when opts could not be undefined",
+                "pr": "TODO"
             }
         ]
     },

packages/sol-compiler/src/compiler.ts

@@ -96,12 +96,12 @@ export class Compiler {
      * @return An instance of the Compiler class.
      */
     constructor(opts?: CompilerOptions) {
-        assert.doesConformToSchema('opts', opts, compilerOptionsSchema);
+        const passedOpts = opts || {};
+        assert.doesConformToSchema('opts', passedOpts, compilerOptionsSchema);
         // TODO: Look for config file in parent directories if not found in current directory
         const config: CompilerOptions = fs.existsSync(CONFIG_FILE)
             ? JSON.parse(fs.readFileSync(CONFIG_FILE).toString())
             : {};
-        const passedOpts = opts || {};
         assert.doesConformToSchema('compiler.json', config, compilerOptionsSchema);
         this._contractsDir = path.resolve(passedOpts.contractsDir || config.contractsDir || DEFAULT_CONTRACTS_DIR);
         this._solcVersionIfExists = passedOpts.solcVersion || config.solcVersion;

packages/sol-compiler/test/compiler_test.ts

@@ -23,6 +23,9 @@ describe('#Compiler', function(): void {
         contractsDir,
         contracts: constants.contracts,
     };
+    it('should create a Compiler with empty opts', async () => {
+        const _compiler = new Compiler();
+    });
     it('should create an Exchange artifact with the correct unlinked binary', async () => {
         compilerOpts.contracts = ['Exchange'];