Q428: Implementation Drill TypeScript Feedback QA Script

What Interviewers Want To Evaluate

This drill tests whether you can verify a TypeScript-specific UI slice after implementation.

The feedback panel changes the run flow.

It needs checks for success, failure, copy behavior, JavaScript separation, dark mode, mobile layout, and runtime output boundaries.

Build passing is necessary.

It is not the whole QA story.

Short Interview Answer

I would run a manual QA script that checks valid TypeScript, invalid TypeScript, runtime errors after successful compilation, copy feedback, JavaScript page separation, theme readability, and mobile layout.

The script should use exact snippets so the result is repeatable.

The goal is to prove compile feedback and runtime output stay separate.

Valid TypeScript Case

Paste:

type User = {
  name: string;
  score: number;
};

const user: User = { name: "Asha", score: 91 };
console.log(user.name, user.score);

Expected:

feedback moves to checking
feedback moves to compiled
runtime console shows output
copy feedback copies compiled message
copy console copies runtime output

This proves the success path.

Invalid TypeScript Case

Paste:

type User = {
  name: string;
};

const user: User = { name: 42 };
console.log(user.name);

Expected:

feedback moves to needs attention
runtime should not show successful output
console explains execution stopped before runtime
copy feedback copies the error message
run button recovers

This proves the compile failure path.

Runtime Error Case

Paste:

type User = {
  name: string;
};

const user = null as unknown as User;
console.log(user.name);

Expected:

TypeScript feedback says compiled
runtime console shows error
feedback panel does not claim TypeScript failed
copy console includes runtime error

This proves compile and runtime signals are separated.

JavaScript Page Check

Open JavaScript practice.

Expected:

no TypeScript feedback panel
run still works
copy code still works
copy console still works
console caps still work
shortcut hints still appear

The JavaScript page should not carry TypeScript-specific UI noise.

Console Cap Cross Check

On the TypeScript page, run:

for (let i = 0; i < 150; i += 1) {
  console.log("ts line", i);
}

Expected:

feedback says compiled
console caps output
truncation notice appears
copy console includes notice

This confirms the new feedback panel did not bypass runtime safety.

Theme Checks

Check:

light theme
dark theme
system theme

Expected:

feedback border is visible
status text is readable
copy button contrast holds
error state is visible without relying only on color
panel background fits the page

Dark mode regressions often appear in new status panels.

Responsive Checks

Check:

laptop
tablet
mobile

Expected:

feedback panel does not crush the editor
copy feedback button wraps cleanly
text stays inside the panel
editor and console remain usable

The panel is secondary.

It should not dominate the practice surface.

Common Mistakes

• Only testing valid TypeScript.
• Not checking runtime errors after successful compilation.
• Forgetting JavaScript should not render the panel.
• Not copying feedback after an error.
• Ignoring mobile wrapping.
• Treating dark mode as an afterthought.

Final Mental Model

TypeScript feedback QA should prove:

compile success is clear
compile failure stops runtime
runtime errors stay in console
copy targets are separate
JavaScript stays simple
themes remain readable

That is the confidence needed before saved snippets.