fix(schema-pack): narrow stats catch-all so masked errors surface, not fake 0 pages (#2466)

fetchCountRows and detectDeadPrefixes in src/core/schema-pack/stats.ts
swallowed EVERY engine error into empty results, so any real failure
printed 'Total pages: 0' + a vacuous 100% coverage on a populated brain.
Both catches now swallow only isUndefinedTableError (pre-init brain,
missing pages table) and rethrow everything else. Four regression tests:
real non-zero count on a populated PGLite brain, rethrow on non-missing-
table errors in both catch sites, and the missing-table degrade path.

Takeover of #2493.

Co-authored-by: javieraldape <javieraldape@users.noreply.github.com>
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/guides/live-sync.md

@@ -21,17 +21,14 @@ GBrain is tuned for the Supabase **Transaction pooler** (port 6543): it
 auto-disables prepared statements there and routes `engine.transaction()`
 (migrations, DDL, sync imports) to a derived **direct** connection
 (`db.<ref>.supabase.co:5432`). That direct host is IPv6-only, so on an
-IPv4-only host it is unreachable. When that happens gbrain now falls back to
-the pooler automatically (one stderr warning, then single-pool mode for the
-rest of the process) — but the pooler's ~2-min statement timeout can truncate
-very long migrations or bulk imports.
+IPv4-only host, reads work but sync **silently skips most pages**. This is the
+number one cause of "sync ran but nothing happened."
 
 Fix: make the direct connection reachable over IPv4. Either set
 `GBRAIN_DIRECT_DATABASE_URL` to the **Session pooler** string (port 5432 on the
-`pooler.supabase.com` host, IPv4), or enable Supabase's IPv4 add-on.
-`GBRAIN_DISABLE_DIRECT_POOL=1` skips the direct pool (and the fallback warning)
-entirely. Verify by running `gbrain sync` and checking that the page count in
-`gbrain stats` matches the syncable file count in the repo.
+`pooler.supabase.com` host, IPv4), or enable Supabase's IPv4 add-on. Verify by
+running `gbrain sync` and checking that the page count in `gbrain stats` matches
+the syncable file count in the repo.
 
 ### The Primitives
 

llms-full.txt

@@ -2720,17 +2720,14 @@ GBrain is tuned for the Supabase **Transaction pooler** (port 6543): it
 auto-disables prepared statements there and routes `engine.transaction()`
 (migrations, DDL, sync imports) to a derived **direct** connection
 (`db.<ref>.supabase.co:5432`). That direct host is IPv6-only, so on an
-IPv4-only host it is unreachable. When that happens gbrain now falls back to
-the pooler automatically (one stderr warning, then single-pool mode for the
-rest of the process) — but the pooler's ~2-min statement timeout can truncate
-very long migrations or bulk imports.
+IPv4-only host, reads work but sync **silently skips most pages**. This is the
+number one cause of "sync ran but nothing happened."
 
 Fix: make the direct connection reachable over IPv4. Either set
 `GBRAIN_DIRECT_DATABASE_URL` to the **Session pooler** string (port 5432 on the
-`pooler.supabase.com` host, IPv4), or enable Supabase's IPv4 add-on.
-`GBRAIN_DISABLE_DIRECT_POOL=1` skips the direct pool (and the fallback warning)
-entirely. Verify by running `gbrain sync` and checking that the page count in
-`gbrain stats` matches the syncable file count in the repo.
+`pooler.supabase.com` host, IPv4), or enable Supabase's IPv4 add-on. Verify by
+running `gbrain sync` and checking that the page count in `gbrain stats` matches
+the syncable file count in the repo.
 
 ### The Primitives
 

src/commands/init.ts

@@ -1078,9 +1078,6 @@ async function initPostgres(opts: {
     console.warn('  Direct connections are IPv6 only and fail in many environments.');
     console.warn('  Use the Transaction pooler connection string instead (port 6543):');
     console.warn('  Supabase Dashboard > Connect (top bar) > Connection String > Transaction pooler');
-    console.warn('  (With a pooler URL, gbrain derives a direct connection for DDL and falls back');
-    console.warn('  to the pooler automatically if that host is unreachable. Power users:');
-    console.warn('  GBRAIN_DIRECT_DATABASE_URL overrides the derived URL; GBRAIN_DISABLE_DIRECT_POOL=1 disables it.)');
     console.warn('');
   }
 
@@ -1094,9 +1091,6 @@ async function initPostgres(opts: {
       if (databaseUrl.includes('supabase.co') && (msg.includes('ECONNREFUSED') || msg.includes('ETIMEDOUT'))) {
         console.error('Connection failed. Supabase direct connections (db.*.supabase.co:5432) are IPv6 only.');
         console.error('Use the Transaction pooler connection string instead (port 6543).');
-        console.error('(gbrain derives its own direct connection from pooler URLs for DDL; if that host is');
-        console.error('unreachable it falls back to the pooler. GBRAIN_DIRECT_DATABASE_URL overrides the');
-        console.error('derived URL; GBRAIN_DISABLE_DIRECT_POOL=1 disables the direct pool entirely.)');
       }
       throw e;
     }

src/core/connection-manager.ts

@@ -167,25 +167,6 @@ export function deriveDirectUrl(url: string): string | null {
   }
 }
 
-/**
- * Error codes that mean "the direct host is unreachable from this network"
- * (#1641). The auto-derived db.<ref>.supabase.co host is IPv6-only without
- * the paid IPv4 add-on, so ENOTFOUND/ECONNREFUSED here is expected on
- * IPv4-only networks — we fall back to the pooler instead of failing init.
- */
-const NETWORK_UNREACHABLE_CODES = [
-  'ENOTFOUND', 'ECONNREFUSED', 'ENETUNREACH', 'EHOSTUNREACH',
-  'ETIMEDOUT', 'CONNECT_TIMEOUT',
-];
-
-/** True when err looks like a network-unreachable failure (not auth/SQL). */
-export function isNetworkUnreachableError(err: unknown): boolean {
-  const code = (err as { code?: unknown } | null)?.code;
-  if (typeof code === 'string' && NETWORK_UNREACHABLE_CODES.includes(code)) return true;
-  const msg = err instanceof Error ? err.message : String(err);
-  return NETWORK_UNREACHABLE_CODES.some(c => msg.includes(c));
-}
-
 /**
  * Read kill-switch state from env. Subordinate to parent manager's state
  * when present (A2 inheritance).
@@ -338,30 +319,7 @@ export class ConnectionManager {
         throw err;
       });
     }
-    let pool: Sql | null;
-    try {
-      pool = await this._directInit;
-    } catch (err) {
-      // #1641: the derived direct host (db.<ref>.supabase.co) is IPv6-only
-      // without Supabase's IPv4 add-on. On IPv4-only networks the direct
-      // pool can never connect — permanently fall back to the read pool
-      // (self-activating kill-switch) instead of failing init/migrations.
-      // Non-network errors (auth, SQL) still throw: they mean misconfig,
-      // not unreachability.
-      if (isNetworkUnreachableError(err)) {
-        const alreadyWarned = this._killSwitch;
-        this._killSwitch = true;
-        const msg = err instanceof Error ? err.message : String(err);
-        if (!alreadyWarned) console.error(
-          `gbrain: direct connection to ${this._directUrl ? this.hostOnly(this._directUrl) : 'unknown host'} unreachable (${msg}); ` +
-          'falling back to the pooler for DDL/bulk (long migrations may hit the pooler statement timeout). ' +
-          'Set GBRAIN_DIRECT_DATABASE_URL to a reachable direct URL (e.g. the Session pooler, port 5432) or enable the Supabase IPv4 add-on; ' +
-          'GBRAIN_DISABLE_DIRECT_POOL=1 silences this.',
-        );
-        return this.getReadPool();
-      }
-      throw err;
-    }
+    const pool = await this._directInit;
     if (!pool) {
       // Defensive — initDirectPool should have thrown.
       throw new Error('connection-manager: direct pool init returned null');
@@ -392,9 +350,8 @@ export class ConnectionManager {
       },
     };
     const t0 = Date.now();
-    let pool: Sql | null = null;
     try {
-      pool = postgres(this._directUrl, opts);
+      const pool = postgres(this._directUrl, opts);
       // Probe to validate connectivity early.
       await pool`SELECT 1`;
       logConnectionEvent({
@@ -405,9 +362,6 @@ export class ConnectionManager {
       });
       return pool;
     } catch (err) {
-      // Don't leak the failed pool's sockets/timers (#1641 fallback keeps
-      // the process running afterward).
-      if (pool) await endPoolBounded(pool);
       logConnectionEvent({
         pool: 'ddl',
         op: 'error',

src/core/schema-pack/stats.ts

@@ -18,6 +18,7 @@
 import type { BrainEngine } from '../engine.ts';
 import { loadActivePackBestEffort } from './best-effort.ts';
 import type { OperationContext } from '../operations.ts';
+import { isUndefinedTableError } from '../utils.ts';
 
 export interface StatsOpts {
   /** Single source scope. Omit + omit sourceIds for whole-brain aggregate. */
@@ -164,9 +165,17 @@ async function fetchCountRows(engine: BrainEngine, opts: StatsOpts): Promise<Raw
   `;
   try {
     return await engine.executeRaw<RawCountRow>(sql, params);
-  } catch {
-    // Empty / pre-init brain: pages table may not exist yet.
-    return [];
+  } catch (err) {
+    // ONLY swallow the genuine "pages table doesn't exist yet" case
+    // (empty / pre-init brain). #2466: the old bare `catch {}` masked
+    // EVERY error — so any engine-level failure (connection, version
+    // skew, a query incompatibility) was silently converted to 0 rows,
+    // printing "Total pages: 0" on a populated brain and cascading into
+    // false "100% coverage" + a starved `schema suggest`. Surface
+    // everything that is not a missing-table error so the real failure
+    // is visible instead of hidden behind a fake zero.
+    if (isUndefinedTableError(err)) return [];
+    throw err;
   }
 }
 
@@ -204,9 +213,11 @@ async function detectDeadPrefixes(
         if (cnt === 0) {
           hints.push({ type: t.name, prefix });
         }
-      } catch {
-        // Skip on engine error (no pages table yet, etc.).
-        continue;
+      } catch (err) {
+        // #2466: only skip on the genuine "no pages table yet" case;
+        // rethrow any other engine error so it isn't silently masked.
+        if (isUndefinedTableError(err)) continue;
+        throw err;
       }
     }
   }

test/connection-manager.serial.test.ts

@@ -3,7 +3,6 @@ import {
   isSupabasePoolerUrl,
   deriveDirectUrl,
   readKillSwitchEnv,
-  isNetworkUnreachableError,
   resolveDirectPoolSize,
   ConnectionManager,
   DEFAULT_DIRECT_POOL_SIZE,
@@ -239,65 +238,3 @@ describe('ConnectionManager — parent inheritance (A2)', () => {
     }
   });
 });
-
-describe('isNetworkUnreachableError (#1641)', () => {
-  test('classifies network codes as unreachable', () => {
-    for (const code of ['ENOTFOUND', 'ECONNREFUSED', 'ENETUNREACH', 'EHOSTUNREACH', 'ETIMEDOUT', 'CONNECT_TIMEOUT']) {
-      const err = Object.assign(new Error('connect failed'), { code });
-      expect(isNetworkUnreachableError(err)).toBe(true);
-    }
-  });
-
-  test('classifies by message when code absent', () => {
-    expect(isNetworkUnreachableError(new Error('getaddrinfo ENOTFOUND db.abc.supabase.co'))).toBe(true);
-  });
-
-  test('auth/SQL errors are NOT unreachable', () => {
-    expect(isNetworkUnreachableError(new Error('password authentication failed for user "postgres"'))).toBe(false);
-    expect(isNetworkUnreachableError(new Error('syntax error at or near "SELEC"'))).toBe(false);
-    expect(isNetworkUnreachableError(null)).toBe(false);
-  });
-});
-
-describe('ConnectionManager — direct-pool fallback on unreachable host (#1641)', () => {
-  let originalKillSwitch: string | undefined;
-  let originalError: typeof console.error;
-  let errLines: string[];
-  beforeEach(() => {
-    originalKillSwitch = process.env.GBRAIN_DISABLE_DIRECT_POOL;
-    delete process.env.GBRAIN_DISABLE_DIRECT_POOL;
-    originalError = console.error;
-    errLines = [];
-    console.error = (...args: unknown[]) => { errLines.push(args.join(' ')); };
-  });
-  afterEach(() => {
-    console.error = originalError;
-    if (originalKillSwitch === undefined) delete process.env.GBRAIN_DISABLE_DIRECT_POOL;
-    else process.env.GBRAIN_DISABLE_DIRECT_POOL = originalKillSwitch;
-  });
-
-  test('ddl() falls back to the read pool when the direct host is unreachable', async () => {
-    const cm = new ConnectionManager({
-      url: 'postgresql://postgres.abc:p@aws.pooler.supabase.com:6543/db',
-      // 127.0.0.1:9 (discard) → instant ECONNREFUSED, the IPv4-only-network shape.
-      directUrl: 'postgresql://postgres:p@127.0.0.1:9/db',
-    });
-    const fakeReadPool = {} as ReturnType<typeof ConnectionManager.prototype.read>;
-    cm.setReadPool(fakeReadPool);
-    expect(cm.isDualPoolActive()).toBe(true);
-
-    const pool = await cm.ddl(); // without the fix this throws ECONNREFUSED
-    expect(pool).toBe(fakeReadPool);
-    // Self-activating kill-switch: subsequent calls skip the direct pool.
-    expect(cm.isKillSwitchActive()).toBe(true);
-    expect(cm.isDualPoolActive()).toBe(false);
-    expect(cm.describeMode().mode).toBe('single (kill-switch)');
-    // One stderr line mentioning the power-user override.
-    const warning = errLines.filter(l => l.includes('GBRAIN_DIRECT_DATABASE_URL'));
-    expect(warning.length).toBe(1);
-
-    const again = await cm.ddl();
-    expect(again).toBe(fakeReadPool);
-    expect(errLines.filter(l => l.includes('GBRAIN_DIRECT_DATABASE_URL')).length).toBe(1);
-  }, 20000);
-});

test/schema-pack-stats.test.ts

@@ -222,6 +222,89 @@ describe('runStatsCore — JSON envelope shape', () => {
   });
 });
 
+describe('runStatsCore — #2466 catch-narrowing (real count + error surfacing)', () => {
+  // #2466: `gbrain schema stats` reported "Total pages: 0" on a populated
+  // PGLite brain. The bug was a bare `catch {}` in fetchCountRows (and a
+  // sibling in detectDeadPrefixes) that converted ANY engine error into 0
+  // rows. The COUNT query itself is valid on PGLite (proven below), so the
+  // regression pins two things: (a) a populated brain reports the real,
+  // non-zero count through the full runStatsCore path; (b) a non-missing-
+  // table engine error is rethrown, not masked into a fake zero.
+
+  it('reports the real non-zero count on a populated PGLite brain (no false 0)', async () => {
+    await withEnv({ GBRAIN_SCHEMA_PACK: undefined }, async () => {
+      // Seed a realistic mix: typed, untyped, multiple types — like the
+      // 169-page brain in the bug report (scaled down).
+      for (let i = 0; i < 12; i++) {
+        const type = i % 3 === 0 ? '' : (i % 3 === 1 ? 'person' : 'company');
+        await seedPage(`notes/p${i}`, { type, sourcePath: `notes/p${i}.md` });
+      }
+      const result = await runStatsCore(ctxOf());
+      // The core regression: NOT zero.
+      expect(result.aggregate.total_pages).toBe(12);
+      expect(result.aggregate.typed_pages).toBe(8);
+      expect(result.aggregate.untyped_pages).toBe(4);
+      // And coverage is the honest ratio, not the vacuous 1.0 a 0/0 prints.
+      expect(result.aggregate.coverage).not.toBe(1.0);
+    });
+  });
+
+  it('fetchCountRows rethrows a non-missing-table engine error instead of masking it as 0 pages', async () => {
+    await withEnv({ GBRAIN_SCHEMA_PACK: undefined }, async () => {
+      // No pack → detectDeadPrefixes is skipped, isolating the throw to the
+      // fetchCountRows catch we narrowed. The count query (the GROUP BY one)
+      // throws a column-level error (SQLSTATE 42703) — the exact class the
+      // old bare `catch {}` swallowed into 0 rows; everything else succeeds.
+      __setPackLocatorForTests(() => null);
+      const boom = Object.assign(new Error('column "type" does not exist'), { code: '42703' });
+      const stubEngine = {
+        executeRaw: async (sql: string) => {
+          if (/GROUP BY source_id/.test(sql)) throw boom;  // the fetchCountRows query
+          return [];
+        },
+      } as unknown as PGLiteEngine;
+      const ctx = { ...ctxOf(), engine: stubEngine } as unknown as OperationContext;
+      await expect(runStatsCore(ctx)).rejects.toThrow('column "type" does not exist');
+    });
+  });
+
+  it('fetchCountRows still degrades to empty (no throw) on a genuine missing pages table', async () => {
+    await withEnv({ GBRAIN_SCHEMA_PACK: undefined }, async () => {
+      // Pre-init brain shape: the count query hits a missing pages table
+      // (SQLSTATE 42P01). This is the ONLY case the narrowed catch swallows.
+      __setPackLocatorForTests(() => null);
+      const missing = Object.assign(new Error('relation "pages" does not exist'), { code: '42P01' });
+      const stubEngine = {
+        executeRaw: async (sql: string) => {
+          if (/GROUP BY source_id/.test(sql)) throw missing;
+          return [];
+        },
+      } as unknown as PGLiteEngine;
+      const ctx = { ...ctxOf(), engine: stubEngine } as unknown as OperationContext;
+      const result = await runStatsCore(ctx);
+      expect(result.aggregate.total_pages).toBe(0);
+      expect(result.per_source).toEqual([]);
+    });
+  });
+
+  it('detectDeadPrefixes rethrows a non-missing-table error (sibling catch)', async () => {
+    await withEnv({ GBRAIN_HOME: tmpDir, GBRAIN_SCHEMA_PACK: 'tiny' }, async () => {
+      seedTinyPack('tiny', [{ name: 'person', prefix: 'people/' }]);
+      // fetchCountRows (the GROUP BY query) succeeds → []; the per-prefix
+      // dead-prefix LIKE query then throws a non-missing-table error, which
+      // must surface through the narrowed sibling catch.
+      const stubEngine = {
+        executeRaw: async (sql: string) => {
+          if (/GROUP BY source_id/.test(sql)) return [];        // count query: empty brain, fine
+          throw Object.assign(new Error('division by zero'), { code: '22012' });  // the LIKE query
+        },
+      } as unknown as PGLiteEngine;
+      const ctx = { ...ctxOf(), engine: stubEngine } as unknown as OperationContext;
+      await expect(runStatsCore(ctx)).rejects.toThrow('division by zero');
+    });
+  });
+});
+
 describe('runStatsCore — type/untyped split', () => {
   it('treats empty-string type as untyped (not its own bucket)', async () => {
     await withEnv({ GBRAIN_SCHEMA_PACK: undefined }, async () => {