Terminal doesn't always render initially when using PseudoTerminal and task custom execution

[GabeDeBacker]

• VSCode Version: Version: 1.43.2 (system setup)
  Commit: 0ba0ca5
  Date: 2020-03-24T07:38:38.248Z
  Electron: 7.1.11
  Chrome: 78.0.3904.130
  Node.js: 12.8.1
  V8: 7.8.279.23-electron.0

• OS Version:
  OS: Windows_NT x64 10.0.19600

Steps to Reproduce:
Our extension registers a custom task provider and it provides tasks with custom execution and the following presentation options:

{
            clear: true,
            focus: false,
            reveal: vscode.TaskRevealKind.Always
};

If the terminal "tab" is not already selected for some other reason (say power shell started, etc.) then when the task runs, the terminal dropdown displays the correct task name, but nothing renders.

Note that adding this simple code:

        vscode.window.onDidOpenTerminal((t) => {
            t.show();
        });

Works around this issue.

Does this issue occur when all extensions are disabled?: Yes

[vscodebot]

(Experimental duplicate detection)
Thanks for submitting this issue. Please also check if it is already covered by an existing one, like:

• Event for a task that never actually starts (#87094)

[Tyriar]

@alexr00 here's what the Terminal.show API calls on the renderer side:

vscode/src/vs/workbench/api/browser/mainThreadTerminalService.ts

Lines 116 to 122 in a15ef2c

	public $show(terminalId: number, preserveFocus: boolean): void {
	const terminalInstance = this._terminalService.getInstanceFromId(terminalId);
	if (terminalInstance) {
	this._terminalService.setActiveInstance(terminalInstance);
	this._terminalService.showPanel(!preserveFocus);
	}
	}

What task reveal does:

vscode/src/vs/workbench/contrib/tasks/browser/terminalTaskSystem.ts

Lines 302 to 325 in a15ef2c

	const isTerminalInPanel: boolean = this.viewDescriptorService.getViewLocation(TERMINAL_VIEW_ID) === ViewContainerLocation.Panel;
	if (isTerminalInPanel && this.isTaskVisible(task)) {
	if (this.previousPanelId) {
	if (this.previousTerminalInstance) {
	this.terminalService.setActiveInstance(this.previousTerminalInstance);
	}
	this.panelService.openPanel(this.previousPanelId);
	} else {
	this.panelService.hideActivePanel();
	}
	this.previousPanelId = undefined;
	this.previousTerminalInstance = undefined;
	} else {
	if (isTerminalInPanel) {
	this.previousPanelId = this.panelService.getActivePanel()?.getId();
	if (this.previousPanelId === TERMINAL_VIEW_ID) {
	this.previousTerminalInstance = this.terminalService.getActiveInstance() ?? undefined;
	}
	}
	this.terminalService.setActiveInstance(terminalData.terminal);
	if (CustomTask.is(task) || ContributedTask.is(task)) {
	this.terminalService.showPanel(task.command.presentation!.focus);
	}
	}

[GabeDeBacker]

@Tyriar & @alexr00 - any update on this? Our customers are starting to notice this issue more.

[alexr00]

@GabeDeBacker I'm not able to repro this now. There were some changes in showing tasks in 1.44, do you still see the issue there?

[Tyriar]

Fixed a similar issue recently #94714

The problem there was that when an extension created a terminal and did not call show and then another terminal is shown, there were actually 2 terminal tabs visible at once, one not being drawn (the initial one) and one being draw but it was offscreen.

[alexr00]

That was probably it then. I tested in master this time so I had the fix for #94714

[alexr00]

@GabeDeBacker can you check in Insiders and see if you still have the same problem?

[GabeDeBacker]

@alexr00 - Hey, sorry about not responding sooner. Checking now

[GabeDeBacker]

@alexr00 - I can confirm that this is indeed addressed in the insiders version. I'm closing this issue.