Watch external pdf files for automatic reload

src/components/manager.ts

@@ -33,8 +33,10 @@ export class Manager {
 
     private extension: Extension
     private fileWatcher?: chokidar.FSWatcher
+    private pdfWatcher?: chokidar.FSWatcher
     private bibWatcher?: chokidar.FSWatcher
     private filesWatched: string[] = []
+    private pdfsWatched: string[] = []
     private bibsWatched: string[] = []
     private watcherOptions: chokidar.WatchOptions
 
@@ -47,8 +49,10 @@ export class Manager {
             useFsEvents: false,
             usePolling,
             interval,
-            binaryInterval: Math.max(interval, 1000)
+            binaryInterval: Math.max(interval, 1000),
+            awaitWriteFinish: true
         }
+        this.initiatePdfWatcher()
     }
 
     /* Returns the output directory developed according to the input tex path
@@ -717,6 +721,37 @@ export class Manager {
         }
     }
 
+    private initiatePdfWatcher() {
+        if (this.pdfWatcher !== undefined) {
+            return
+        }
+        this.extension.logger.addLogMessage('Creating file watcher for .pdf files.')
+        this.pdfWatcher = chokidar.watch([], this.watcherOptions)
+        this.pdfWatcher.on('change', (file: string) => this.onWatchedPdfChanged(file))
+        this.pdfWatcher.on('unlink', (file: string) => this.onWatchedPdfDeleted(file))
+    }
+
+    private onWatchedPdfChanged(file: string) {
+        this.extension.logger.addLogMessage(`PDF file watcher - responding to change in ${file}`)
+        this.extension.viewer.refreshExistingViewer()
+    }
+
+    onWatchedPdfDeleted(file: string) {
+        this.extension.logger.addLogMessage(`PDF file watcher: ${file} deleted.`)
+        if (this.pdfWatcher) {
+            this.pdfWatcher.unwatch(file)
+        }
+        this.pdfsWatched.splice(this.pdfsWatched.indexOf(file), 1)
+    }
+
+    watchPdfFile(pdfPath: string) {
+        if (this.pdfWatcher && !this.pdfsWatched.includes(pdfPath)) {
+            this.extension.logger.addLogMessage(`Adding .pdf file ${pdfPath} to pdf file watcher.`)
+            this.pdfWatcher.add(pdfPath)
+            this.pdfsWatched.push(pdfPath)
+        }
+    }
+
     private buildOnFileChanged(file: string, bibChanged: boolean = false) {
         const configuration = vscode.workspace.getConfiguration('latex-workshop')
         if (configuration.get('latex.autoBuild.run') as string !== 'onFileChange') {

src/main.ts

@@ -142,6 +142,7 @@ export function activate(context: vscode.ExtensionContext) {
         }
 
         if (e.languageId === 'pdf') {
+            extension.manager.watchPdfFile(e.uri.fsPath)
             vscode.commands.executeCommand('workbench.action.closeActiveEditor').then(() => {
                 extension.commander.pdf(e.uri)
             })