feat(bazel): improve error output on intgeration test failure

We should print the working directory of the test on failure, allowing
developers to quickly jump to the test directory on failure. Currently
this is hard to spot when the integration test produced a lot of output.

bazel/integration/test_runner/runner.ts

@@ -9,26 +9,31 @@
 import * as fs from 'fs';
 import * as path from 'path';
 import * as tmp from 'tmp';
-import {addWritePermissionFlag, writeExecutableFile} from './file_system_utils';
-import {
-  PackageMappings,
-  readPackageJsonContents,
-  updateMappingsForPackageJson,
-} from './package_json';
+
 import {
   BazelExpandedValue,
   BazelFileInfo,
   resolveBazelFile,
   resolveBinaryWithRunfilesGracefully,
 } from './bazel';
-import {debug} from './debug';
+import {
+  PackageMappings,
+  readPackageJsonContents,
+  updateMappingsForPackageJson,
+} from './package_json';
+import {addWritePermissionFlag, writeExecutableFile} from './file_system_utils';
 import {
   expandEnvironmentVariableSubstitutions,
   getBinaryPassThroughScript,
   prependToPathVariable,
   runCommandInChildProcess,
 } from './process_utils';
+
 import {ENVIRONMENT_TMP_PLACEHOLDER} from './constants';
+import {debug} from './debug';
+
+/** Error class that is used when an integration command fails.  */
+class IntegrationTestCommandError extends Error {}
 
 /**
  * Test runner that takes a set of files within a Bazel package and copies the files
@@ -230,10 +235,11 @@ export class TestRunner {
       );
 
       if (!success) {
-        throw Error(
-          `Integration test command: \`${resolvedBinary} ${evaluatedArgs.join(' ')}\` failed. ` +
-            `See error output above for details.`,
-        );
+        console.error(`Command failed: \`${resolvedBinary} ${evaluatedArgs.join(' ')}\``);
+        console.error(`Command ran in test directory: ${path.normalize(testDir)}`);
+        console.error(`See error output above.`);
+
+        throw new IntegrationTestCommandError();
       }
     }
   }