fix: exit with non-zero exit code if there are compilation errors (#442)

In #383 we modified the compiler to continue jsii validation despite
compilation errors but did not propagate the fact that there were
compilation errors.

This resulted in "jsii" exiting with a 0 exit code even in case
of errors.

Fixes #441

packages/jsii/bin/jsii.ts

@@ -43,7 +43,7 @@ import { VERSION } from '../lib/version';
     for (const diagnostic of emitResult.diagnostics) {
         utils.logDiagnostic(diagnostic, projectRoot);
     }
-    if (emitResult.emitSkipped) {
+    if (emitResult.hasErrors) {
         process.exit(1);
     }
 }).catch(e => {

packages/jsii/lib/assembler.ts

@@ -8,7 +8,7 @@ import path = require('path');
 import ts = require('typescript');
 import { JSII_DIAGNOSTICS_CODE } from './compiler';
 import { getReferencedDocParams, parseSymbolDocumentation } from './docs';
-import { Diagnostic, Emitter } from './emitter';
+import { Diagnostic, Emitter, EmitResult } from './emitter';
 import literate = require('./literate');
 import { ProjectInfo } from './project-info';
 import utils = require('./utils');
@@ -90,7 +90,7 @@ export class Assembler implements Emitter {
       // Clearing ``this._types`` to allow contents to be garbage-collected.
       delete this._types;
       try {
-        return { diagnostics: this._diagnostics, emitSkipped: true };
+        return { diagnostics: this._diagnostics, hasErrors: true };
       } finally {
         // Clearing ``this._diagnostics`` to allow contents to be garbage-collected.
         delete this._diagnostics;
@@ -121,7 +121,7 @@ export class Assembler implements Emitter {
 
     const validator = new Validator(this.projectInfo, assembly);
     const validationResult = await validator.emit();
-    if (!validationResult.emitSkipped) {
+    if (!validationResult.hasErrors) {
       const assemblyPath = path.join(this.projectInfo.projectRoot, '.jsii');
       LOG.trace(`Emitting assembly: ${colors.blue(assemblyPath)}`);
       await fs.writeJson(assemblyPath, _fingerprint(assembly), { replacer: utils.filterEmpty, spaces: 2 });
@@ -130,7 +130,7 @@ export class Assembler implements Emitter {
     try {
       return {
         diagnostics: [...this._diagnostics, ...validationResult.diagnostics],
-        emitSkipped: validationResult.emitSkipped
+        hasErrors: validationResult.hasErrors
       };
     } finally {
       // Clearing ``this._types`` to allow contents to be garbage-collected.
@@ -1232,22 +1232,6 @@ export class Assembler implements Emitter {
   }
 }
 
-/**
- * The result of ``Assembler#emit()``.
- */
-export interface EmitResult {
-  /**
-   * @return all diagnostic information produced by the assembler's emit process
-   */
-  readonly diagnostics: ts.Diagnostic[];
-
-  /**
-   * @return true if the assembly was not written to disk (as the consequence
-   *         of errors, which are visible in ``#diagnostics``)
-   */
-  readonly emitSkipped: boolean;
-}
-
 function _fingerprint(assembly: spec.Assembly): spec.Assembly {
   delete assembly.fingerprint;
   assembly = sortJson(assembly);

packages/jsii/lib/compiler.ts

@@ -149,12 +149,12 @@ export class Compiler implements Emitter {
         // jsii warnings will appear.
         const assembler = new Assembler(this.options.projectInfo, program, stdlib);
         const assmEmit = await assembler.emit();
-        if (assmEmit.emitSkipped) {
+        if (assmEmit.hasErrors) {
             LOG.error('Type model errors prevented the JSII assembly from being created');
         }
 
         return {
-            emitSkipped: assmEmit.emitSkipped,
+            hasErrors: emit.emitSkipped || assmEmit.hasErrors,
             diagnostics: [...emit.diagnostics, ...assmEmit.diagnostics]
         };
     }

packages/jsii/lib/emitter.ts

@@ -17,7 +17,7 @@ export interface Emitter {
  */
 export interface EmitResult {
     /** Whether the emit was skipped as a result of errors (found in ``diagnostics``) */
-    emitSkipped: boolean;
+    hasErrors: boolean;
 
     /** Diagnostic information created when trying to emit stuff */
     diagnostics: ReadonlyArray<ts.Diagnostic | Diagnostic>;

packages/jsii/lib/validator.ts

@@ -26,7 +26,7 @@ export class Validator implements Emitter {
         try {
             return {
                 diagnostics: this._diagnostics,
-                emitSkipped: this._diagnostics.find(diag => diag.category === ts.DiagnosticCategory.Error) != null
+                hasErrors: this._diagnostics.find(diag => diag.category === ts.DiagnosticCategory.Error) != null
             };
         } finally {
             // Clearing ``this._diagnostics`` to allow contents to be garbage-collected.

packages/jsii/test/negatives/neg.compilation-error.ts

@@ -0,0 +1,4 @@
+///!MATCH_ERROR: Cannot find name 'boom'.
+///!MATCH_ERROR: Cannot find name 'CompilerErrorIsHere'.
+
+boom! >CompilerErrorIsHere

packages/jsii/test/test.negatives.ts

@@ -17,7 +17,7 @@ for (const source of fs.readdirSync(SOURCE_DIR)) {
         test.ok(expectations.length > 0, `Expected error messages should be specified using ${MATCH_ERROR_MARKER}`);
         const compiler = new Compiler({ projectInfo: _makeProjectInfo(source), watch: false });
         const emitResult = await compiler.emit(path.join(SOURCE_DIR, source));
-        test.equal(emitResult.emitSkipped, true, `emitSkipped should be true`);
+        test.equal(emitResult.hasErrors, true, `hasErrors should be true`);
         const errors = emitResult.diagnostics.filter(diag => diag.category === ts.DiagnosticCategory.Error);
         for (const expectation of expectations) {
             test.notEqual(errors.find(e => _messageText(e).indexOf(expectation) !== -1),