plandex-ai/plandex · error

failed to parse the original content: %v

Error message

failed to parse the original content: %v

What it means

ExecApplyTreeSitter applies a proposed edit by parsing both the original and the edited (comment-normalized) content with tree-sitter and then aligning the trees. Before any comparison it parses the original source; a ParseCtx failure here is wrapped as 'failed to parse the original content: %v'. Called by ApplyChanges when executing structured (tree-sitter) edits.

Source

Thrown at app/server/syntax/structured_edits_tree_sitter.go:98

			// keep indentation for syntax parsing
			content := strings.TrimSpace(line)

			if removalsByLine[Removal(i+1)] || refsByLine[Reference(i+1)] {
				comment := openingCommentSymbol + " ref " + closingCommentSymbol
				proposedLines[i] = strings.Replace(line, content, comment, 1)
			}
		}
	}

	proposedWithNormalizedComments := strings.Join(proposedLines, "\n")
	res.Proposed = proposedWithNormalizedComments

	originalBytes := []byte(original)
	proposedBytes := []byte(proposedWithNormalizedComments)

	originalTree, err := parser.ParseCtx(ctx, nil, originalBytes)
	if err != nil {
		return nil, fmt.Errorf("failed to parse the original content: %v", err)
	}
	defer originalTree.Close()

	proposedTree, err := parser.ParseCtx(ctx, nil, proposedBytes)
	if err != nil {
		return nil, fmt.Errorf("failed to parse the proposed content: %v", err)
	}
	defer proposedTree.Close()

	if verboseLogging {
		fmt.Printf("anchorLines: %v\n", anchorLines)
	}

	oRes := BuildNodeIndex(originalTree)
	pRes := BuildNodeIndex(proposedTree)

	originalNodesByLineIndex := oRes.nodesByLine
	proposedNodesByLineIndex := pRes.nodesByLine

View on GitHub (pinned to e2d772072e)

Solutions

1. Fix the syntax errors in the original file before applying tree-sitter edits
2. Verify the correct parser/language is being selected for the file path
3. Fall back to a plain (non-tree-sitter) text replacement for files that won't parse
4. Check the wrapped '%v' cause for cancellation/operation-limit and adjust the context/limits

Example fix

// before
res, err := edits.ApplyChanges(path, original, proposed)
// after
if err := syntax.ValidateFile(path, original); err != nil {
    // fall back to plain string replacement
    return plainReplace(original, proposed)
}
res, err := edits.ApplyChanges(path, original, proposed)

vres, err := syntax.ValidateWithParsers(lang, original, parsers)
if err != nil || vres == nil || vres.ParseHasError {
    return fmt.Errorf("original not parseable; use plain text edit")
}

func canTreeSitterApply(lang shared.Language, original string, parsers []*syntax.Parser) bool {
    res, err := syntax.ValidateWithParsers(lang, original, parsers)
    return err == nil && res != nil && !res.ParseHasError
}

res, err := ApplyChanges(path, original, proposed)
if err != nil && strings.Contains(err.Error(), "failed to parse the original content") {
    return plainTextReplace(original, proposed) // fallback
}

When it happens

Trigger: ApplyChanges → ExecApplyTreeSitter is invoked with an original file whose content fails to parse with the selected parser — e.g. the file contains syntax errors, is empty, or the wrong parser/language was chosen for it.

Common situations: Applying an edit to a file that was already syntactically broken; language detection mismatch (file edited under a different grammar than its content); truncated or concurrently-modified file content; context cancelled mid-parse.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• failed to parse the proposed content: %v
• failed to parse the content: %v
• error mapping file %s: %v
• failed to parse file: %v
• failed to parse the content with fallback parser: %v

AI-assisted analysis of plandex-ai/plandex@e2d772072e (2026-09-05). Data as JSON: /api/errors/bad63ec061bba79e. Report an issue: GitHub.