The comparison should use >= instead of >. When block assembly has exactly the same number of transactions as the block needs (e.g., both are 400), the optimization should still apply since we have all the transactions locally.

This edge case is unlikely but would unnecessarily fetch from the peer when we already have all needed transactions.

Fixed in ed654de — changed to >= so when TxCount equals TransactionCount we still skip the expensive peer fetch.

GetBlockAssemblyState is called with the request context and no deadline. If the blockassembly service is unreachable or the connection isn’t ready, this RPC can block indefinitely (gRPC waits for readiness until ctx.Done()), potentially stalling block validation. Consider wrapping this call in a short context.WithTimeout (and optionally logging baErr at debug level) so subtree validation can fall back to the existing peer-fetch path promptly when blockassembly is unavailable.

Fixed — wrapped GetBlockAssemblyState in a 2s context.WithTimeout. If blockassembly is unreachable, the timeout fires and we fall through to the existing peer-fetch path. The error is silently ignored (baErr check already handles it).

The optimization condition uses state.TxCount > uint64(block.TransactionCount). If blockassembly has exactly the number of transactions the block needs, the expensive peer subtree_data fetch will still run. If the intent is “enough txs locally”, this should likely be >= (and it may be worth clarifying whether TxCount includes the coinbase placeholder so the comparison is correct).

Fixed — same as the other comment, changed to >=.

This test doesn’t actually verify that the /subtree_data/ fetch is skipped: it uses an unreachable BaseUrl, so the earlier /subtree/ structure fetch fails and the code never reaches the subtree_data branch regardless of localTxsAvailable. To validate the optimization, make the subtree structure available (e.g., store FileTypeSubtreeToCheck in subtreeStore or mock the /subtree/ endpoint) and then assert that the /subtree_data/ request is not made (e.g., via httpmock expectations).

Reworked the test. Now stores FileTypeSubtreeToCheck in the store (bypasses /subtree/ HTTP fetch), uses httpmock to intercept HTTP calls, and verifies the error does NOT come from the CheckBlockSubtrees subtree_data fetch path. Note: ValidateSubtreeInternal has its own subtree_data fallback for missing txs — that is a separate code path unaffected by this optimization.

The doc comment for New lists parameters only up to txmetaConsumerClient, but the function now takes additional dependencies (p2pClient and blockAssemblyClient). Please update the parameter documentation to match the signature so callers understand what to pass and what the dependency is used for.

Fixed — added p2pClient and blockAssemblyClient to the parameter documentation in the New() doc comment.

startValidationService now hard-requires a blockassembly gRPC client for the subtree validation service. blockassembly.NewClient returns configuration/connection errors (e.g., when BlockAssembly.GRPCAddress is unset), so this change can prevent the SubtreeValidation service from starting even though the optimization is optional (the server already nil-checks u.blockAssemblyClient). Consider making this dependency best-effort here: if config is missing or the client can’t be created, log a warning and pass nil so subtree validation continues using the existing peer-fetch path.

Fixed — blockassembly client creation failure now logs a warning and passes nil. The subtreevalidation server already nil-checks blockAssemblyClient, so it falls through to the existing peer-fetch path.

This new test doesn’t actually assert that the /subtree_data/ HTTP fetch is skipped by CheckBlockSubtrees: it only checks that the returned error string does not contain "failed to get subtree data from". If CheckBlockSubtrees still performs the fetch but then fails later (e.g., with "failed to process subtree data stream"), this test would still pass.

To make the assertion robust, explicitly assert the HTTP call count for the /subtree_data/ endpoint is zero. Since ValidateSubtreeInternal can also fetch /subtree_data/ as a fallback, consider forcing that path off in this test (e.g., set server.settings.SubtreeValidation.PercentageMissingGetFullData > 100) so any /subtree_data/ request can only come from CheckBlockSubtrees.

Strengthened the assertion. Now sets PercentageMissingGetFullData=101 to disable ValidateSubtreeInternal's fallback subtree_data fetch, then iterates httpmock call counts to verify no subtree_data endpoint was contacted. Any subtree_data call at that point can only come from CheckBlockSubtrees itself.

When localTxsAvailable is true, this branch skips populating subtreeTxs[subtreeIdx], but the code already preallocates make([]*bt.Tx, 0, subtreeToCheck.Length()) unconditionally just above. That backing array can be large and becomes wasted allocation on the skip path, reducing the benefit of avoiding subtree_data downloads. Consider moving the preallocation into the !localTxsAvailable/subtreeDataExists paths (only when you will actually append txs) and leaving the slice nil/empty-cap when skipping.

Fixed — moved the pre-allocation into the two paths that actually populate the slice (peer fetch and stored file extraction). When localTxsAvailable skips the fetch, no backing array is allocated.