build(broccoli): refactor typescript plugin to be incremental via DiffingBroccoliPlugin

tools/broccoli/broccoli-typescript.ts

@@ -0,0 +1,172 @@
+/// <reference path="../typings/node/node.d.ts" />
+/// <reference path="../../node_modules/typescript/bin/typescript.d.ts" />
+
+import fs = require('fs');
+import fse = require('fs-extra');
+import path = require('path');
+import ts = require('typescript');
+import {wrapDiffingPlugin, DiffingBroccoliPlugin, DiffResult} from './diffing-broccoli-plugin';
+
+
+type FileRegistry = ts.Map<{version: number}>;
+
+const FS_OPTS = {encoding: 'utf-8'};
+
+
+/**
+ * Broccoli plugin that implements incremental Typescript compiler.
+ *
+ * It instantiates a typescript compiler instance that keeps all the state about the project and
+ * can reemit only the files that actually changed.
+ *
+ * Limitations: only files that map directly to the changed source file via naming conventions are
+ * reemited. This primarily affects code that uses `const enum`s, because changing the enum value
+ * requires global emit, which can affect many files.
+ */
+class DiffingTSCompiler implements DiffingBroccoliPlugin {
+  private tsOpts: ts.CompilerOptions;
+  private fileRegistry: FileRegistry = Object.create(null);
+  private rootFilePaths: string[];
+  private tsServiceHost: ts.LanguageServiceHost;
+  private tsService: ts.LanguageService;
+
+
+  constructor(public inputPath: string, public cachePath: string, public options) {
+    this.tsOpts = Object.create(options);
+    this.tsOpts.outDir = this.cachePath;
+    this.tsOpts.target = (<any>ts).ScriptTarget[options.target];
+    this.rootFilePaths = options.rootFilePaths ? options.rootFilePaths.splice(0) : [];
+    this.tsServiceHost = new CustomLanguageServiceHost(this.tsOpts, this.rootFilePaths,
+                                                       this.fileRegistry, this.inputPath);
+    this.tsService = ts.createLanguageService(this.tsServiceHost, ts.createDocumentRegistry())
+  }
+
+
+  rebuild(treeDiff: DiffResult) {
+    let pathsToEmit = [];
+    let pathsWithErrors = [];
+
+    treeDiff.changedPaths.filter((changedPath) =>
+                                     changedPath.match(/\.ts/) && !changedPath.match(/\.d\.ts/))
+        .forEach((tsFilePath) => {
+          if (!this.fileRegistry[tsFilePath]) {
+            this.fileRegistry[tsFilePath] = {version: 0};
+            this.rootFilePaths.push(tsFilePath);
+          } else {
+            this.fileRegistry[tsFilePath].version++;
+          }
+
+          pathsToEmit.push(tsFilePath);
+        });
+
+    treeDiff.removedPaths.filter((changedPath) =>
+                                     changedPath.match(/\.ts/) && !changedPath.match(/\.d\.ts/))
+        .forEach((tsFilePath) => {
+          console.log('removing outputs for', tsFilePath);
+
+          this.rootFilePaths.splice(this.rootFilePaths.indexOf(tsFilePath), 1);
+          this.fileRegistry[tsFilePath] = null;
+
+          let jsFilePath = tsFilePath.replace(/\.ts$/, '.js');
+          let mapFilePath = tsFilePath.replace(/.ts$/, '.js.map');
+          let dtsFilePath = tsFilePath.replace(/\.ts$/, '.d.ts');
+
+          fs.unlinkSync(path.join(this.cachePath, jsFilePath));
+          fs.unlinkSync(path.join(this.cachePath, mapFilePath));
+          fs.unlinkSync(path.join(this.cachePath, dtsFilePath));
+        });
+
+    pathsToEmit.forEach((tsFilePath) => {
+      let output = this.tsService.getEmitOutput(tsFilePath);
+
+      if (output.emitSkipped) {
+        let errorFound = this.logError(tsFilePath);
+        if (errorFound) {
+          pathsWithErrors.push(tsFilePath);
+        }
+      } else {
+        output.outputFiles.forEach(o => {
+          let destDirPath = path.dirname(o.name);
+          fse.mkdirsSync(destDirPath);
+          fs.writeFileSync(o.name, o.text, FS_OPTS);
+        });
+      }
+    });
+
+    if (pathsWithErrors.length) {
+      throw new Error('Typescript found errors listed above...');
+    }
+  }
+
+
+  private logError(tsFilePath) {
+    let allDiagnostics = this.tsService.getCompilerOptionsDiagnostics()
+                             .concat(this.tsService.getSyntacticDiagnostics(tsFilePath))
+                             .concat(this.tsService.getSemanticDiagnostics(tsFilePath));
+
+    allDiagnostics.forEach(diagnostic => {
+      let message = ts.flattenDiagnosticMessageText(diagnostic.messageText, "\n");
+      if (diagnostic.file) {
+        let{line, character} = diagnostic.file.getLineAndCharacterOfPosition(diagnostic.start);
+        console.log(`  Error ${diagnostic.file.fileName} (${line + 1},${character + 1}): ` +
+                    `${message}`);
+      } else {
+        console.log(`  Error: ${message}`);
+      }
+    });
+
+    return !!allDiagnostics.length;
+  }
+}
+
+
+class CustomLanguageServiceHost implements ts.LanguageServiceHost {
+  private currentDirectory: string;
+  private defaultLibFilePath: string;
+
+
+  constructor(private compilerOptions: ts.CompilerOptions, private fileNames: string[],
+              private fileRegistry: FileRegistry, private treeInputPath: string) {
+    this.currentDirectory = process.cwd();
+    this.defaultLibFilePath = ts.getDefaultLibFilePath(compilerOptions);
+  }
+
+
+  getScriptFileNames(): string[] { return this.fileNames; }
+
+
+  getScriptVersion(fileName: string): string {
+    return this.fileRegistry[fileName] && this.fileRegistry[fileName].version.toString();
+  }
+
+
+  getScriptSnapshot(tsFilePath: string): ts.IScriptSnapshot {
+    // TODO: this method is called a lot, add cache
+
+    let absoluteTsFilePath = (tsFilePath == this.defaultLibFilePath) ?
+                                 tsFilePath :
+                                 path.join(this.treeInputPath, tsFilePath);
+
+    if (!fs.existsSync(absoluteTsFilePath)) {
+      // TypeScript seems to request lots of bogus paths during import path lookup and resolution,
+      // so we we just return undefined when the path is not correct.
+      return undefined;
+    }
+    return ts.ScriptSnapshot.fromString(fs.readFileSync(absoluteTsFilePath, FS_OPTS));
+  }
+
+
+  getCurrentDirectory(): string { return this.currentDirectory; }
+
+
+  getCompilationSettings(): ts.CompilerOptions { return this.compilerOptions; }
+
+
+  getDefaultLibFileName(options: ts.CompilerOptions): string {
+    // ignore options argument, options should not change during the lifetime of the plugin
+    return this.defaultLibFilePath;
+  }
+}
+
+
+export default wrapDiffingPlugin(DiffingTSCompiler);