From 99dec836d5d150b84bd6b198e82ec0b214a7ae70 Mon Sep 17 00:00:00 2001 From: Tom Alexander Date: Wed, 12 Aug 2026 12:59:29 -0400 Subject: [PATCH] feat(app): merge and source-list primitives for cross-source search Two pure pieces the search page needs before it can span sources. The merge interleaves several already-ordered row streams into one timestamp-ordered list, bounded by a "safe frontier": the timestamp every stream has covered. Rows older than that are held back, so the timeline never shows a gap a slower stream could still fill, and the caller is told which streams are holding the frontier so only those need another page. Streams that error or are excluded stop bounding the frontier rather than freezing the list. The param resolver extends the existing single-source one to a list, deduping, capping, and reporting entries it could not resolve so one bad name doesn't sink the whole selection. Both are unit-tested; nothing calls them yet. --- .../utils/__tests__/multiSourceMerge.test.ts | 379 ++++++++++++++++++ .../src/utils/__tests__/sourceParams.test.ts | 63 +++ packages/app/src/utils/multiSourceMerge.ts | 239 +++++++++++ packages/app/src/utils/sourceParams.ts | 45 +++ 4 files changed, 726 insertions(+) create mode 100644 packages/app/src/utils/__tests__/multiSourceMerge.test.ts create mode 100644 packages/app/src/utils/multiSourceMerge.ts diff --git a/packages/app/src/utils/__tests__/multiSourceMerge.test.ts b/packages/app/src/utils/__tests__/multiSourceMerge.test.ts new file mode 100644 index 0000000000..ae77b18f9e --- /dev/null +++ b/packages/app/src/utils/__tests__/multiSourceMerge.test.ts @@ -0,0 +1,379 @@ +import { + computeFrontier, + coveredUntil, + mergeStreams, + MULTI_SOURCE_ROW_FIELDS, + StreamSnapshot, +} from '@/utils/multiSourceMerge'; + +const TS_KEY = '__hdx_timestamp'; + +const T = (iso: string) => new Date(iso); +const ms = (iso: string) => new Date(iso).getTime(); + +// Search range: 10:00 - 12:00 UTC +const DATE_RANGE: [Date, Date] = [ + T('2026-08-07T10:00:00Z'), + T('2026-08-07T12:00:00Z'), +]; + +const row = (iso: string, extra: Record = {}) => ({ + [TS_KEY]: iso, + ...extra, +}); + +const makeStream = ( + overrides: Partial & { sourceId: string }, +): StreamSnapshot => ({ + sourceName: overrides.sourceId, + rows: [], + window: null, + lastPageRowCount: null, + hasNextPage: true, + isActive: true, + dateRange: DATE_RANGE, + ...overrides, +}); + +const parseTs = (r: Record) => new Date(r[TS_KEY]).getTime(); + +describe('coveredUntil (DESC)', () => { + it('covers the whole range when the stream is fully drained', () => { + const stream = makeStream({ + sourceId: 'a', + hasNextPage: false, + window: { + startTime: T('2026-08-07T10:00:00Z'), + endTime: T('2026-08-07T12:00:00Z'), + }, + lastPageRowCount: 0, + }); + expect(coveredUntil(stream, 'DESC', parseTs)).toBe(DATE_RANGE[0].getTime()); + }); + + it('covers nothing during the initial fetch even though hasNextPage is still false', () => { + // useInfiniteQuery reports hasNextPage=false before the first page lands; + // that must not be mistaken for a drained stream. + const stream = makeStream({ sourceId: 'a', hasNextPage: false }); + expect(coveredUntil(stream, 'DESC', parseTs)).toBe(DATE_RANGE[1].getTime()); + }); + + it('covers nothing before the first page arrives', () => { + const stream = makeStream({ sourceId: 'a' }); + expect(coveredUntil(stream, 'DESC', parseTs)).toBe(DATE_RANGE[1].getTime()); + }); + + it('covers through the window start when the last page was empty', () => { + const stream = makeStream({ + sourceId: 'a', + window: { + startTime: T('2026-08-07T11:45:00Z'), + endTime: T('2026-08-07T12:00:00Z'), + }, + lastPageRowCount: 0, + }); + expect(coveredUntil(stream, 'DESC', parseTs)).toBe( + ms('2026-08-07T11:45:00Z'), + ); + }); + + it('covers only through the oldest fetched row when stopped mid-window at LIMIT', () => { + const stream = makeStream({ + sourceId: 'a', + rows: [row('2026-08-07T11:59:00Z'), row('2026-08-07T11:50:00Z')], + window: { + startTime: T('2026-08-07T11:45:00Z'), + endTime: T('2026-08-07T12:00:00Z'), + }, + lastPageRowCount: 2, + }); + expect(coveredUntil(stream, 'DESC', parseTs)).toBe( + ms('2026-08-07T11:50:00Z'), + ); + }); +}); + +describe('coveredUntil (ASC)', () => { + it('mirrors the DESC semantics from the start of the range', () => { + expect(coveredUntil(makeStream({ sourceId: 'a' }), 'ASC', parseTs)).toBe( + DATE_RANGE[0].getTime(), + ); + expect( + coveredUntil( + makeStream({ + sourceId: 'a', + hasNextPage: false, + window: { + startTime: T('2026-08-07T10:00:00Z'), + endTime: T('2026-08-07T12:00:00Z'), + }, + lastPageRowCount: 0, + }), + 'ASC', + parseTs, + ), + ).toBe(DATE_RANGE[1].getTime()); + expect( + coveredUntil( + makeStream({ + sourceId: 'a', + window: { + startTime: T('2026-08-07T10:00:00Z'), + endTime: T('2026-08-07T10:15:00Z'), + }, + lastPageRowCount: 0, + }), + 'ASC', + parseTs, + ), + ).toBe(ms('2026-08-07T10:15:00Z')); + }); +}); + +const drainedStream = (sourceId: string) => + makeStream({ + sourceId, + hasNextPage: false, + window: { + startTime: T('2026-08-07T10:00:00Z'), + endTime: T('2026-08-07T12:00:00Z'), + }, + lastPageRowCount: 0, + }); + +describe('computeFrontier', () => { + it('is the least-covered active stream (max for DESC)', () => { + const drained = drainedStream('a'); + const midWindow = makeStream({ + sourceId: 'b', + rows: [row('2026-08-07T11:50:00Z')], + window: { + startTime: T('2026-08-07T11:45:00Z'), + endTime: T('2026-08-07T12:00:00Z'), + }, + lastPageRowCount: 1, + }); + expect(computeFrontier([drained, midWindow], 'DESC', parseTs)).toBe( + ms('2026-08-07T11:50:00Z'), + ); + }); + + it('ignores inactive (errored/excluded) streams so they cannot stall the merge', () => { + const drained = drainedStream('a'); + const errored = makeStream({ sourceId: 'b', isActive: false }); + expect(computeFrontier([drained, errored], 'DESC', parseTs)).toBe( + DATE_RANGE[0].getTime(), + ); + }); + + it('is null when no stream is active', () => { + const errored = makeStream({ sourceId: 'a', isActive: false }); + expect(computeFrontier([errored], 'DESC', parseTs)).toBeNull(); + }); +}); + +describe('mergeStreams', () => { + const window0 = { + startTime: T('2026-08-07T11:45:00Z'), + endTime: T('2026-08-07T12:00:00Z'), + }; + + it('interleaves rows across streams newest-first and tags their source', () => { + const a = makeStream({ + sourceId: 'a', + sourceName: 'app logs', + rows: [row('2026-08-07T11:59:00Z'), row('2026-08-07T11:57:00Z')], + window: window0, + lastPageRowCount: 2, + hasNextPage: false, + }); + const b = makeStream({ + sourceId: 'b', + sourceName: 'traces', + rows: [row('2026-08-07T11:58:00Z')], + window: window0, + lastPageRowCount: 1, + hasNextPage: false, + }); + + const { rows } = mergeStreams([a, b], 'DESC', TS_KEY); + + expect(rows.map(r => r[TS_KEY])).toEqual([ + '2026-08-07T11:59:00Z', + '2026-08-07T11:58:00Z', + '2026-08-07T11:57:00Z', + ]); + expect(rows.map(r => r[MULTI_SOURCE_ROW_FIELDS.SOURCE_NAME])).toEqual([ + 'app logs', + 'traces', + 'app logs', + ]); + expect(rows[0][MULTI_SOURCE_ROW_FIELDS.SOURCE_ID]).toBe('a'); + }); + + it('holds back rows older than the frontier until lagging streams catch up', () => { + // Stream a is fully drained down to 10:00; stream b stopped at LIMIT with + // its oldest row at 11:50 — anything older than 11:50 from a must wait. + const a = makeStream({ + sourceId: 'a', + rows: [ + row('2026-08-07T11:55:00Z'), + row('2026-08-07T11:49:00Z'), // older than b's coverage — held back + ], + window: window0, + lastPageRowCount: 2, + hasNextPage: false, + }); + const b = makeStream({ + sourceId: 'b', + rows: [row('2026-08-07T11:50:00Z')], + window: window0, + lastPageRowCount: 1, + hasNextPage: true, + }); + + const { rows, frontier, laggingSourceIds } = mergeStreams( + [a, b], + 'DESC', + TS_KEY, + ); + + expect(frontier).toBe(ms('2026-08-07T11:50:00Z')); + expect(rows.map(r => r[TS_KEY])).toEqual([ + '2026-08-07T11:55:00Z', + '2026-08-07T11:50:00Z', + ]); + expect(laggingSourceIds).toEqual(['b']); + }); + + it('shows everything when all streams are drained', () => { + const a = makeStream({ + sourceId: 'a', + rows: [row('2026-08-07T10:05:00Z')], + window: window0, + lastPageRowCount: 1, + hasNextPage: false, + }); + const b = makeStream({ + sourceId: 'b', + rows: [row('2026-08-07T10:03:00Z')], + window: window0, + lastPageRowCount: 1, + hasNextPage: false, + }); + + const { rows, laggingSourceIds } = mergeStreams([a, b], 'DESC', TS_KEY); + + expect(rows).toHaveLength(2); + expect(laggingSourceIds).toEqual([]); + }); + + it('holds everything back while a stream has no page yet, without marking it lagging', () => { + const a = makeStream({ + sourceId: 'a', + rows: [row('2026-08-07T11:59:00Z')], + window: window0, + lastPageRowCount: 1, + hasNextPage: false, + }); + const pending = makeStream({ sourceId: 'b' }); + + const { rows, laggingSourceIds } = mergeStreams( + [a, pending], + 'DESC', + TS_KEY, + ); + + // Frontier sits at the range end until b's first page lands. + expect(rows).toEqual([]); + // b's initial fetch is already in flight — nothing to advance. + expect(laggingSourceIds).toEqual([]); + }); + + it('still shows rows from errored streams but never waits on them', () => { + const a = makeStream({ + sourceId: 'a', + rows: [row('2026-08-07T11:59:00Z')], + window: window0, + lastPageRowCount: 1, + hasNextPage: false, + }); + const errored = makeStream({ + sourceId: 'b', + rows: [row('2026-08-07T11:58:00Z')], + window: window0, + lastPageRowCount: 1, + isActive: false, + }); + + const { rows, laggingSourceIds } = mergeStreams( + [a, errored], + 'DESC', + TS_KEY, + ); + + expect(rows.map(r => r[TS_KEY])).toEqual([ + '2026-08-07T11:59:00Z', + '2026-08-07T11:58:00Z', + ]); + expect(laggingSourceIds).toEqual([]); + }); + + it('merges oldest-first with a mirrored frontier for ASC', () => { + const window0Asc = { + startTime: T('2026-08-07T10:00:00Z'), + endTime: T('2026-08-07T10:15:00Z'), + }; + const a = makeStream({ + sourceId: 'a', + rows: [ + row('2026-08-07T10:01:00Z'), + row('2026-08-07T10:20:00Z'), // beyond b's coverage — held back + ], + window: window0Asc, + lastPageRowCount: 2, + hasNextPage: false, + }); + const b = makeStream({ + sourceId: 'b', + rows: [row('2026-08-07T10:05:00Z')], + window: window0Asc, + lastPageRowCount: 1, + hasNextPage: true, + }); + + const { rows, frontier, laggingSourceIds } = mergeStreams( + [a, b], + 'ASC', + TS_KEY, + ); + + expect(frontier).toBe(ms('2026-08-07T10:05:00Z')); + expect(rows.map(r => r[TS_KEY])).toEqual([ + '2026-08-07T10:01:00Z', + '2026-08-07T10:05:00Z', + ]); + expect(laggingSourceIds).toEqual(['b']); + }); + + it('advances every stream tied at the frontier', () => { + const a = makeStream({ + sourceId: 'a', + rows: [row('2026-08-07T11:50:00Z')], + window: window0, + lastPageRowCount: 1, + hasNextPage: true, + }); + const b = makeStream({ + sourceId: 'b', + rows: [row('2026-08-07T11:50:00Z')], + window: window0, + lastPageRowCount: 1, + hasNextPage: true, + }); + + const { laggingSourceIds } = mergeStreams([a, b], 'DESC', TS_KEY); + + expect(laggingSourceIds).toEqual(['a', 'b']); + }); +}); diff --git a/packages/app/src/utils/__tests__/sourceParams.test.ts b/packages/app/src/utils/__tests__/sourceParams.test.ts index d26d25c538..c2a86598c7 100644 --- a/packages/app/src/utils/__tests__/sourceParams.test.ts +++ b/packages/app/src/utils/__tests__/sourceParams.test.ts @@ -2,6 +2,7 @@ import { SourceKind } from '@hyperdx/common-utils/dist/types'; import { resolveSourceParam, + resolveSourcesParam, SourceForParamResolution, } from '@/utils/sourceParams'; @@ -174,3 +175,65 @@ describe('resolveSourceParam', () => { }); }); }); + +describe('resolveSourcesParam', () => { + it('resolves a list by ID and by name', () => { + expect(resolveSourcesParam(['log-1', 'Traces'], SOURCES)).toEqual({ + status: 'resolved', + sources: [LOGS_1, TRACES], + unresolved: [], + }); + }); + + it('reports pending while sources are loading', () => { + expect(resolveSourcesParam(['log-1'], undefined)).toEqual({ + status: 'pending', + }); + }); + + it('resolves an empty selection without waiting on the source list', () => { + expect(resolveSourcesParam([], undefined)).toEqual({ + status: 'resolved', + sources: [], + unresolved: [], + }); + }); + + it('keeps what resolves and reports the rest, so one bad entry does not sink the selection', () => { + expect(resolveSourcesParam(['log-1', 'Nope', 'Traces'], SOURCES)).toEqual({ + status: 'resolved', + sources: [LOGS_1, TRACES], + unresolved: ['Nope'], + }); + }); + + it('reports an entry naming a source of the wrong kind', () => { + expect( + resolveSourcesParam(['log-1', 'Traces'], SOURCES, { + kinds: [SourceKind.Log], + }), + ).toEqual({ + status: 'resolved', + sources: [LOGS_1], + unresolved: ['Traces'], + }); + }); + + it('dedupes entries that resolve to the same source', () => { + expect(resolveSourcesParam(['log-1', 'log-1'], SOURCES)).toEqual({ + status: 'resolved', + sources: [LOGS_1], + unresolved: [], + }); + }); + + it('caps the selection at `max`, keeping the first entries', () => { + expect( + resolveSourcesParam(['log-1', 'Traces', 'Old Logs'], SOURCES, { max: 2 }), + ).toEqual({ + status: 'resolved', + sources: [LOGS_1, TRACES], + unresolved: [], + }); + }); +}); diff --git a/packages/app/src/utils/multiSourceMerge.ts b/packages/app/src/utils/multiSourceMerge.ts new file mode 100644 index 0000000000..ae53b730c4 --- /dev/null +++ b/packages/app/src/utils/multiSourceMerge.ts @@ -0,0 +1,239 @@ +/** + * Pure merge logic for multi-source search: k-way merges per-source result + * streams by timestamp, bounded by a "safe frontier" so the interleaved + * timeline never shows a gap another source could still fill. + * + * Every source stream paginates through the same progressive time windows + * (see utils/searchWindows.ts — windows are a pure function of the date + * range), but streams advance at different speeds: one source may be three + * windows deep while another is still mid-window at its row LIMIT. A merged + * DESC timeline is only correct down to the timestamp every stream has + * covered; rows older than that are held back until the lagging streams catch + * up. + */ + +/** Client-side fields tagged onto every merged row. Never sent to ClickHouse. */ +export const MULTI_SOURCE_ROW_FIELDS = { + SOURCE_ID: '__hdx_source_id', + SOURCE_NAME: '__hdx_source_name', + SOURCE_COLOR: '__hdx_source_color', +} as const; + +export type MergeDirection = 'ASC' | 'DESC'; + +export type StreamSnapshot = { + sourceId: string; + sourceName: string; + /** Badge/series color for this source; tagged onto rows for the table cell. */ + sourceColor?: string; + /** + * Rows fetched so far, in stream order (newest-first for DESC, + * oldest-first for ASC) — the order the windowed query produces. + */ + rows: Record[]; + /** The last fetched page's time window; null when no page has completed. */ + window: { startTime: Date; endTime: Date } | null; + /** + * Row count of the last fetched page; 0 means the window was drained, + * >0 means the stream may have stopped mid-window at its LIMIT. + * Null when no page has completed. + */ + lastPageRowCount: number | null; + hasNextPage: boolean; + /** + * Errored/excluded streams don't bound the frontier (they'd stall the merge + * forever); their already-fetched rows are still shown. + */ + isActive: boolean; + /** The full searched range, used when a stream is fully drained. */ + dateRange: [Date, Date]; +}; + +/** + * Epoch-ms timestamp T such that this stream is guaranteed to have produced + * every row it has on the already-covered side of T: + * DESC — all of the stream's rows with ts >= T are fetched; + * ASC — all of the stream's rows with ts <= T are fetched. + * + * Conservative by construction: when the stream stopped mid-window at its + * LIMIT, coverage only extends to the last row it returned, not the window + * boundary. + */ +export function coveredUntil( + stream: StreamSnapshot, + direction: MergeDirection, + parseTs: (row: Record) => number, +): number { + const [start, end] = stream.dateRange; + + if (stream.window == null || stream.lastPageRowCount == null) { + // Nothing fetched yet: no coverage at all. Checked before hasNextPage — + // useInfiniteQuery reports hasNextPage=false during the initial fetch, + // which must not read as "fully drained". + return direction === 'DESC' ? end.getTime() : start.getTime(); + } + + if (!stream.hasNextPage) { + // Fully drained: the stream covered the entire searched range. + return direction === 'DESC' ? start.getTime() : end.getTime(); + } + + if (stream.lastPageRowCount === 0) { + // The last window came back empty, so it is fully covered. + return direction === 'DESC' + ? stream.window.startTime.getTime() + : stream.window.endTime.getTime(); + } + + // Mid-window at LIMIT: covered only through the last row returned. Rows are + // in stream order, so the last row is the furthest-along one. + const lastRow = stream.rows[stream.rows.length - 1]; + if (lastRow == null) { + // Defensive: a non-zero lastPageRowCount implies rows exist. + return direction === 'DESC' + ? stream.window.endTime.getTime() + : stream.window.startTime.getTime(); + } + return parseTs(lastRow); +} + +/** + * The merge frontier: the timestamp every active stream has covered. + * DESC — rows with ts >= frontier are safe to show; ASC — ts <= frontier. + * Null when there are no active streams (nothing bounds the merge). + */ +export function computeFrontier( + streams: StreamSnapshot[], + direction: MergeDirection, + parseTs: (row: Record) => number, +): number | null { + let frontier: number | null = null; + for (const stream of streams) { + if (!stream.isActive) continue; + const covered = coveredUntil(stream, direction, parseTs); + if (frontier == null) { + frontier = covered; + } else { + frontier = + direction === 'DESC' + ? Math.max(frontier, covered) + : Math.min(frontier, covered); + } + } + return frontier; +} + +/** + * The active streams holding the frontier back that can be advanced with + * another page fetch. Streams whose initial fetch hasn't completed are not + * included — their in-flight request IS their advancement. + */ +function laggingStreams( + streams: StreamSnapshot[], + direction: MergeDirection, + parseTs: (row: Record) => number, +): StreamSnapshot[] { + const frontier = computeFrontier(streams, direction, parseTs); + if (frontier == null) return []; + return streams.filter( + stream => + stream.isActive && + stream.hasNextPage && + stream.window != null && + coveredUntil(stream, direction, parseTs) === frontier, + ); +} + +export type MergedRow = Record; + +/** + * Merge all fetched rows across streams into one timestamp-ordered list, + * tagged with their origin source, held back at the frontier. + * + * Rows from inactive (errored/excluded) streams are still included — they are + * valid data — but only active streams bound the frontier, so a dead source + * can't freeze the timeline. + */ +function mergeStreamRows( + streams: StreamSnapshot[], + direction: MergeDirection, + timestampKey: string, +): MergedRow[] { + // Timestamps repeat heavily at second precision; cache the Date parse per + // distinct raw value (same trick as ChartUtils' time-chart transform). + const tsCache = new Map(); + const parseTs = (row: Record): number => { + const raw = row[timestampKey]; + let ts = tsCache.get(raw); + if (ts === undefined) { + ts = new Date(raw).getTime(); + tsCache.set(raw, ts); + } + return ts; + }; + + const frontier = computeFrontier(streams, direction, parseTs); + + const tagged: { row: MergedRow; ts: number }[] = []; + for (const stream of streams) { + for (const row of stream.rows) { + const ts = parseTs(row); + if ( + frontier != null && + (direction === 'DESC' ? ts < frontier : ts > frontier) + ) { + continue; + } + tagged.push({ + row: { + ...row, + [MULTI_SOURCE_ROW_FIELDS.SOURCE_ID]: stream.sourceId, + [MULTI_SOURCE_ROW_FIELDS.SOURCE_NAME]: stream.sourceName, + ...(stream.sourceColor != null + ? { [MULTI_SOURCE_ROW_FIELDS.SOURCE_COLOR]: stream.sourceColor } + : {}), + }, + ts, + }); + } + } + + // Array.prototype.sort is stable, so ties keep (stream order, row order). + tagged.sort((a, b) => (direction === 'DESC' ? b.ts - a.ts : a.ts - b.ts)); + + return tagged.map(t => t.row); +} + +/** + * Convenience wrapper used by the table component: one pass producing the + * merged rows, the frontier (for the "loading up to" indicator), and which + * streams to advance on the next fetch. + */ +export function mergeStreams( + streams: StreamSnapshot[], + direction: MergeDirection, + timestampKey: string, +): { + rows: MergedRow[]; + frontier: number | null; + laggingSourceIds: string[]; +} { + const tsCache = new Map(); + const parseTs = (row: Record): number => { + const raw = row[timestampKey]; + let ts = tsCache.get(raw); + if (ts === undefined) { + ts = new Date(raw).getTime(); + tsCache.set(raw, ts); + } + return ts; + }; + + return { + rows: mergeStreamRows(streams, direction, timestampKey), + frontier: computeFrontier(streams, direction, parseTs), + laggingSourceIds: laggingStreams(streams, direction, parseTs).map( + s => s.sourceId, + ), + }; +} diff --git a/packages/app/src/utils/sourceParams.ts b/packages/app/src/utils/sourceParams.ts index 5874111c99..dc759c11b7 100644 --- a/packages/app/src/utils/sourceParams.ts +++ b/packages/app/src/utils/sourceParams.ts @@ -55,6 +55,51 @@ export type SourceParamResolution = * lowest ID, so the same link always resolves to the same source no matter what * order the API returns them in. */ +/** + * Resolve a list of source params (IDs or names) for multi-source search. + * Each element resolves with the same rules as `resolveSourceParam`; results + * are deduped by ID and capped at `max`. Elements that can't be resolved (or + * resolve to a source of the wrong kind) are reported in `unresolved` so the + * caller can warn without failing the rest of the selection. + */ +export function resolveSourcesParam( + paramValues: string[] | null | undefined, + sources: T[] | undefined, + { kinds, max }: { kinds?: SourceKind[]; max?: number } = {}, +): + | { status: 'pending' } + | { status: 'resolved'; sources: T[]; unresolved: string[] } { + if (paramValues == null || paramValues.length === 0) { + return { status: 'resolved', sources: [], unresolved: [] }; + } + if (sources == null) return { status: 'pending' }; + + const resolved: T[] = []; + const seenIds = new Set(); + const unresolved: string[] = []; + + for (const value of paramValues) { + const resolution = resolveSourceParam(value, sources, { kinds }); + if (resolution.status === 'resolved') { + if (!seenIds.has(resolution.source.id)) { + seenIds.add(resolution.source.id); + resolved.push(resolution.source); + } + } else if ( + resolution.status === 'not-found' || + resolution.status === 'wrong-kind' + ) { + unresolved.push(value); + } + } + + return { + status: 'resolved', + sources: max != null ? resolved.slice(0, max) : resolved, + unresolved, + }; +} + export function resolveSourceParam( paramValue: string | null | undefined, sources: T[] | undefined,