chore: Remove casts when accessing config props (#374)

src/agent/debuglet.ts

@@ -37,7 +37,6 @@ import {Controller} from './controller';
 import {Debuggee} from '../debuggee';
 import {StatusMessage} from '../client/stackdriver/status-message';
 
-// The following import syntax is used because './config' has a default export
 import {defaultConfig} from './config';
 import * as scanner from './io/scanner';
 import * as SourceMapper from './io/sourcemapper';
@@ -283,10 +282,8 @@ export class Debuglet extends EventEmitter {
     const stat = promisify(fs.stat);
 
     try {
-      // TODO: Address the fact that `that.config.workingDirectory` could
-      //       be `null`.
       await stat(
-          path.join(that.config.workingDirectory as string, 'package.json'));
+          path.join(that.config.workingDirectory, 'package.json'));
     } catch (err) {
       that.logger.error('No package.json located in working directory.');
       that.emit('initError', new Error('No package.json found.'));
@@ -301,10 +298,8 @@ export class Debuglet extends EventEmitter {
 
     let fileStats: scanner.ScanResults;
     try {
-      // TODO: Address the case when `that.config.workingDirectory` is
-      //       `null`.
       fileStats = await scanner.scan(
-          !id, that.config.workingDirectory as string, /.js$|.map$/);
+          !id, that.config.workingDirectory, /.js$|.map$/);
     } catch (err) {
       that.logger.error('Error scanning the filesystem.', err);
       that.emit('initError', err);

src/agent/state/inspector-state.ts

@@ -294,14 +294,12 @@ class StateResolver {
 
   stripCurrentWorkingDirectory_(path: string): string {
     // Strip 1 extra character to remove the slash.
-    // TODO: Handle the case where `this.config.workingDirectory` is `null`.
-    return path.substr((this.config.workingDirectory as string).length + 1);
+    return path.substr((this.config.workingDirectory!).length + 1);
   }
 
   isPathInCurrentWorkingDirectory_(path: string): boolean {
     // return true;
-    // TODO: Handle the case where `this.config.workingDirectory` is `null`.
-    return path.indexOf(this.config.workingDirectory as string) === 0;
+    return path.indexOf(this.config.workingDirectory) === 0;
   }
 
   isPathInNodeModulesDirectory_(path: string): boolean {

src/agent/state/legacy-state.ts

@@ -293,14 +293,12 @@ class StateResolver {
 
   stripCurrentWorkingDirectory_(path: string): string {
     // Strip 1 extra character to remove the slash.
-    // TODO: Handle the case where `this.config.workingDirectory` is `null`.
-    return path.substr((this.config.workingDirectory as string).length + 1);
+    return path.substr((this.config.workingDirectory).length + 1);
   }
 
   isPathInCurrentWorkingDirectory_(path: string): boolean {
     // return true;
-    // TODO: Handle the case where `this.config.workingDirectory` is `null`.
-    return path.indexOf(this.config.workingDirectory as string) === 0;
+    return path.indexOf(this.config.workingDirectory) === 0;
   }
 
   isPathInNodeModulesDirectory_(path: string): boolean {

src/agent/util/utils.ts

@@ -3,7 +3,7 @@ import * as path from 'path';
 import {StatusMessage} from '../../client/stackdriver/status-message';
 import * as stackdriver from '../../types/stackdriver';
 
-import {DebugAgentConfig} from '../config';
+import {ResolvedDebugAgentConfig} from '../config';
 import {ScanStats} from '../io/scanner';
 
 
@@ -39,13 +39,12 @@ export interface Listener {
 }
 // Exposed for unit testing.
 export function findScripts(
-    scriptPath: string, config: DebugAgentConfig,
+    scriptPath: string, config: ResolvedDebugAgentConfig,
     fileStats: ScanStats): string[] {
   // Use repository relative mapping if present.
   if (config.appPathRelativeToRepository) {
     const candidate = scriptPath.replace(
-        // TODO: Address the case where `config.workingDirectory` is `null`.
-        config.appPathRelativeToRepository, config.workingDirectory as string);
+        config.appPathRelativeToRepository, config.workingDirectory);
     // There should be no ambiguity resolution if project root is provided.
     return fileStats[candidate] ? [candidate] : [];
   }

test/test-v8debugapi.ts

@@ -166,8 +166,7 @@ describe('v8debugapi', () => {
 
   beforeEach((done) => {
     if (!api) {
-      // TODO: Handle the case when config.workingDirectory is null
-      scanner.scan(true, config.workingDirectory as string, /.js$|.map$/)
+      scanner.scan(true, config.workingDirectory, /.js$|.map$/)
           .then((fileStats) => {
             const jsStats = fileStats.selectStats(/.js$/);
             const mapFiles = fileStats.selectFiles(/.map$/, process.cwd());