Skip to content

Throw when FixedPortGenerator runs out of ports #1383

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
cristianrgreco wants to merge 2 commits into from
Closed

Throw when FixedPortGenerator runs out of ports #1383

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
7c01e7b
Throw when FixedPortGenerator runs out of ports
cristianrgreco Jun 22, 2026
3f8f3d8
Reject instead of throwing synchronously on port exhaustion
cristianrgreco Jun 23, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
9 changes: 9 additions & 0 deletions packages/testcontainers/src/utils/port-generator.test.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -8,6 +8,15 @@ describe("PortGenerator", () => {
await expect(fixedPortGenerator.generatePort()).resolves.toBe(1000);
await expect(fixedPortGenerator.generatePort()).resolves.toBe(1001);
});

it("should reject when no more ports are available", async () => {
const fixedPortGenerator = new FixedPortGenerator([1000]);

await expect(fixedPortGenerator.generatePort()).resolves.toBe(1000);
await expect(fixedPortGenerator.generatePort()).rejects.toThrowError(
"FixedPortGenerator has no more ports available"
);
});
});

describe("RandomPortGenerator", () => {
Expand Down
7 changes: 5 additions & 2 deletions packages/testcontainers/src/utils/port-generator.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -14,7 +14,10 @@ export class FixedPortGenerator implements PortGenerator {

constructor(private readonly ports: number[]) {}

public generatePort(): Promise<number> {
return Promise.resolve(this.ports[this.portIndex++]);
public async generatePort(): Promise<number> {
if (this.portIndex >= this.ports.length) {
throw new Error("FixedPortGenerator has no more ports available");

@chatgpt-codex-connector chatgpt-codex-connector Bot Jun 22, 2026

Copy link
Copy Markdown

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

P2 Badge Preserve the promise contract on exhaustion

generatePort() is typed through PortGenerator as returning Promise<number>, but this branch throws before returning a Promise. In contexts that consume the promised API directly, such as generator.generatePort().catch(...) or collecting calls for Promise.all, exhaustion will escape synchronously instead of being handled as a rejection; RandomPortGenerator and the interface both expose asynchronous failure semantics, so this should reject the returned promise (for example by making the method async or returning Promise.reject(...)).

Useful? React with 👍 / 👎.

}
return this.ports[this.portIndex++];
}
}
Loading