Editors

@backplane-labs/backplane-editors exports lazy CodeMirror controls: CodeEditor, InlineCodeEditor, QueryEditor, JSONViewer, DiffViewer and EditorActions. The author supplies an accessible label, controlled string value and theme mode. English resources are exported as editorsEnglish for backplane.editors. CodeMirror and its merge view are separate dynamic imports.

Query language choices are explicit source capabilities. CEL, MetricsQL, PromQL, LogsQL and TraceQL have lexical highlighting and keyword completion. Highlighting does not establish that an expression is valid: callers supply authoritative validate and complete callbacks. These receive cancellation signals; stale results are discarded. Completion output is bounded to 500 entries, diagnostic output to 1,000 entries. Ranges are UTF-16 code-unit offsets and are clamped to the document. JSON uses CodeMirror's JSON parser diagnostics; YAML has syntax highlighting and relies on the caller for diagnostics.

complete may answer a list (replacing the word before the cursor) or { from, options } (replacing from an explicit offset: a field after x., a YAML key). Without validate, the diagnostics prop is the lint result, so a lint pass never clears them. hover(position) gives a tooltip text, reveal selects and scrolls to a range whenever its key changes, onCursor reports the cursor, height="fill" takes the container's height and hideMessages leaves the list of diagnostics to the host.

Ctrl/Cmd+Enter runs a query. Escape followed by Tab leaves the editor; Tab otherwise indents. Completion, readonly editing, cancellation, language changes, both themes and accessibility are checked in Storybook. Diagnostic/suggestion failure keeps the text and reports unavailability. No query or mutation is automatically retried.

The editable value and diff inputs are strings. Raw JSON text preserves numeric lexemes above 2^53 without parsing them through Number. For object previews, bigints become decimal strings; use protobuf JSON if type distinctions must be represented. Preview text is escaped by React/CodeMirror. Copy/download operates on the original string, not the rendered syntax spans.