can1357/oh-my-pi · error · ParseError

Line hint must be >= 1

Error message

Line hint must be >= 1

What it means

Thrown when an '@@' change-context header carries a line hint (e.g. '@@ near line 0') parsed by LINE_HINT_REGEX and the extracted hint is less than 1. Line hints resolve ambiguous context markers to a concrete anchor line, and the parser enforces 1-based positive numbering just like unified headers. It fails fast at the header line rather than mis-anchoring the patch.

Source

Thrown at packages/coding-agent/src/edit/diff.ts:594

			throw new ParseError("Line numbers in @@ header must be >= 1", lineNumber);
		}
		if (unifiedHeader.changeContext) {
			changeContexts.push(unifiedHeader.changeContext);
		}
		oldStartLine = unifiedHeader.oldStartLine;
		newStartLine = unifiedHeader.newStartLine;
		startIndex = 1;
	} else if (isHeaderLine && headerTrimmed.startsWith(CHANGE_CONTEXT_MARKER)) {
		const contextValue = headerTrimmed.slice(CHANGE_CONTEXT_MARKER.length);
		const trimmedContextValue = contextValue.trim();
		const normalizedContextValue = trimmedContextValue.replace(/^@@\s*/u, "");

		const lineHintMatch = normalizedContextValue.match(LINE_HINT_REGEX);
		if (lineHintMatch) {
			oldStartLine = Number(lineHintMatch[1]);
			newStartLine = oldStartLine;
			if (oldStartLine < 1) {
				throw new ParseError("Line hint must be >= 1", lineNumber);
			}
		} else if (TOP_OF_FILE_REGEX.test(normalizedContextValue)) {
			oldStartLine = 1;
			newStartLine = 1;
		} else if (trimmedContextValue.length > 0) {
			changeContexts.push(contextValue);
		}
		startIndex = 1;
	} else if (isHeaderLine) {
		const contextValue = headerTrimmed.slice(2).trim();
		if (contextValue.length > 0) {
			changeContexts.push(contextValue);
		}
		startIndex = 1;
	} else {
		if (!allowMissingContext) {
			throw new ParseError(`Expected hunk to start with @@ context marker, got: '${lines[0]}'`, lineNumber);
		}

View on GitHub (pinned to 9690622007)

Solutions

1. Change the line hint to 1-based: use 'line 1' or a top-of-file marker instead of 'line 0'.
2. Drop the line hint entirely and let the surrounding context text locate the hunk.
3. Fix the generating code to add 1 when converting from 0-based indices.
4. Pre-validate header hints with a regex before calling the parser.

Example fix

// before
@@ src/app.ts line 0
// after
@@ src/app.ts line 1

const hint = contextHeader.match(/line\s+(-?\d+)/i);
if (hint && Number(hint[1]) < 1) {
  throw new Error(`Line hint must be >= 1, got ${hint[1]}; use 'line 1' or top-of-file`);
}

try {
  hunks = parseDiffHunks(diff);
} catch (err) {
  if (err instanceof ParseError && err.message === "Line hint must be >= 1") {
    // rewrite 'line 0' hints to 'line 1' and retry once
  } else throw err;
}

When it happens

Trigger: Calling parseDiffHunks on a patch whose context header contains a line hint of 0 or negative, e.g. '@@ foo.js line 0' or '@@ near line -2'.

Common situations: LLM- or template-generated patches where a 'line 0' hint means 'top of file'; scripts that compute hint line numbers with 0-based indices; hand-edited patches after copy/paste.

Related errors

• Line numbers in @@ header must be >= 1
• Line numbers must be >= 1 (got ${oldStartLine})
• Line numbers must be >= 1 (got ${newStartLine})
• Unknown changelog category: ${raw}
• No JSON payload found in response

AI-assisted analysis of can1357/oh-my-pi@9690622007 (2026-08-31). Data as JSON: /api/errors/02b940009141c76a. Report an issue: GitHub.