fix #6767: don't reuse integrated terminal that has child processes

packages/debug/src/browser/debug-session.tsx

@@ -368,13 +368,20 @@ export class DebugSession implements CompositeTreeElement {
     }
 
     protected async runInTerminal({ arguments: { title, cwd, args, env } }: DebugProtocol.RunInTerminalRequest): Promise<DebugProtocol.RunInTerminalResponse['body']> {
-        const terminal = await this.doCreateTerminal({ title, cwd, env });
+        const terminal = await this.doCreateTerminal({ title, cwd, env, useServerTitle: false });
         terminal.sendText(args.join(' ') + '\n');
         return { processId: await terminal.processId };
     }
 
     protected async doCreateTerminal(options: TerminalWidgetOptions): Promise<TerminalWidget> {
-        let terminal = this.terminalServer.all.find(t => t.title.label === options.title || t.title.caption === options.title);
+        let terminal = undefined;
+        for (const t of this.terminalServer.all) {
+            if ((t.title.label === options.title || t.title.caption === options.title) && (await t.hasChildProcesses()) === false) {
+                terminal = t;
+                break;
+            }
+        }
+
         if (!terminal) {
             terminal = await this.terminalServer.newTerminal(options);
             await terminal.start();

packages/terminal/src/browser/base/terminal-widget.ts

@@ -47,6 +47,11 @@ export abstract class TerminalWidget extends BaseWidget {
      * Cleat terminal output.
      */
     abstract clearOutput(): void;
+
+    /**
+     * Whether the terminal process has child processes.
+     */
+    abstract hasChildProcesses(): Promise<boolean>;
 }
 
 /**

packages/terminal/src/browser/terminal-widget-impl.ts

@@ -263,6 +263,10 @@ export class TerminalWidgetImpl extends TerminalWidget implements StatefulWidget
         this.term.clear();
     }
 
+    async hasChildProcesses(): Promise<boolean> {
+        return this.shellTerminalServer.hasChildProcesses(await this.processId);
+    }
+
     storeState(): object {
         this.closeOnDispose = false;
         return { terminalId: this.terminalId, titleLabel: this.title.label };

packages/terminal/src/common/shell-terminal-protocol.ts

@@ -20,6 +20,7 @@ import { IBaseTerminalServer, IBaseTerminalServerOptions } from './base-terminal
 export const IShellTerminalServer = Symbol('IShellTerminalServer');
 
 export interface IShellTerminalServer extends IBaseTerminalServer {
+    hasChildProcesses(processId: number | undefined): Promise<boolean>;
 }
 
 export const shellTerminalPath = '/services/shell-terminal';

packages/terminal/src/node/shell-terminal-server.ts

@@ -20,6 +20,8 @@ import { IShellTerminalServerOptions } from '../common/shell-terminal-protocol';
 import { BaseTerminalServer } from '../node/base-terminal-server';
 import { ShellProcessFactory } from '../node/shell-process';
 import { ProcessManager } from '@theia/process/lib/node';
+import { isWindows } from '@theia/core/lib/common/os';
+import * as cp from 'child_process';
 
 @injectable()
 export class ShellTerminalServer extends BaseTerminalServer {
@@ -41,4 +43,46 @@ export class ShellTerminalServer extends BaseTerminalServer {
             return Promise.resolve(-1);
         }
     }
+
+    // copied and modified from https://github.com/microsoft/vscode/blob/4636be2b71c87bfb0bfe3c94278b447a5efcc1f1/src/vs/workbench/contrib/debug/node/terminals.ts#L32-L75
+    private spawnAsPromised(command: string, args: string[]): Promise<string> {
+        return new Promise((resolve, reject) => {
+            let stdout = '';
+            const child = cp.spawn(command, args);
+            if (child.pid) {
+                child.stdout.on('data', (data: Buffer) => {
+                    stdout += data.toString();
+                });
+            }
+            child.on('error', err => {
+                reject(err);
+            });
+            child.on('close', code => {
+                resolve(stdout);
+            });
+        });
+    }
+
+    public hasChildProcesses(processId: number | undefined): Promise<boolean> {
+        if (processId) {
+            // if shell has at least one child process, assume that shell is busy
+            if (isWindows) {
+                return this.spawnAsPromised('wmic', ['process', 'get', 'ParentProcessId']).then(stdout => {
+                    const pids = stdout.split('\r\n');
+                    return pids.some(p => parseInt(p) === processId);
+                }, error => true);
+            } else {
+                return this.spawnAsPromised('/usr/bin/pgrep', ['-lP', String(processId)]).then(stdout => {
+                    const r = stdout.trim();
+                    if (r.length === 0 || r.indexOf(' tmux') >= 0) { // ignore 'tmux';
+                        return false;
+                    } else {
+                        return true;
+                    }
+                }, error => true);
+            }
+        }
+        // fall back to safe side
+        return Promise.resolve(true);
+    }
 }