Add proptest-based fuzz and pipeline integration tests for Solana IDL parsing

[shahan-khatchadourian-anchorage]

Summary

Adds property-based fuzz and pipeline integration tests for Solana IDL parsing.

• fuzz_idl_parsing.rs: crash-safety property tests verifying that decode_idl_data and parse_instruction_with_idl never panic regardless of IDL shape or instruction byte content — covers random IDLs, valid discriminator prefixes with random arg bytes, defined struct types, nested Vec/Option containers, and SizeGuard boundary conditions
• pipeline_integration.rs: end-to-end property tests through parse_transaction covering discriminator dispatch, field count invariants, named accounts, and multi-program transactions
• src/.cargo/config.toml (gitignored): local dev override that redirects the solana_parser git dependency to a local checkout without committing a [patch] block

The tests depend on solana_parser::arb, a new proptest strategies module being added to solana-parser in a companion PR.

Merge order

Step 1: Merge anchorageoss/solana-parser#1 first. That PR adds the proptest feature and arb module to solana-parser.

Step 2: Update src/chain_parsers/visualsign-solana/Cargo.toml in this PR — change both solana_parser entries from branch = "solana-parser-add-arbitrary" to point at main (or a pinned commit/tag on main).

Step 3: Merge this PR.

Test plan

• cargo test --test fuzz_idl_parsing — 19 tests pass
• cargo test --test pipeline_integration — 9 tests pass

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Adds property-based fuzzing and end-to-end pipeline integration tests to harden Solana IDL parsing and visualization against panics and regressions.

Changes:

• Added proptest fuzz tests covering decode_idl_data + parse_instruction_with_idl crash-safety, plus roundtrip and SizeGuard boundary assertions.
• Added full-pipeline integration tests exercising transaction_to_visual_sign with/without IDL registration, discriminator dispatch, named accounts, and multi-instruction transactions.
• Updated visualsign-solana to use an anchorageoss/solana-parser git dependency and introduced a helper script to run fuzzing against embedded real-world IDLs.

Reviewed changes

Copilot reviewed 6 out of 8 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/chain_parsers/visualsign-solana/tests/pipeline_integration.rs	New end-to-end + proptest-based pipeline tests for IDL-driven visualization.
src/chain_parsers/visualsign-solana/tests/fuzz_idl_parsing.rs	New proptest fuzz + roundtrip tests for solana_parser IDL parsing APIs.
src/chain_parsers/visualsign-solana/tests/fuzz_idl_parsing.proptest-regressions	Adds saved proptest regression seeds for reproducibility.
src/chain_parsers/visualsign-solana/Cargo.toml	Switches solana_parser git source and adds proptest dev dependencies.
src/Cargo.toml	No functional change (formatting).
src/Cargo.lock	Updates locked dependencies for new solana_parser/proptest usage.
scripts/fuzz_all_idls.sh	New script to run fuzz tests across embedded Solana IDLs.
.gitignore	Ignores src/.cargo/ for local dependency override configs.

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[Copilot]

@prasanna-anchorage I've opened a new pull request, #219, to work on those changes. Once the pull request is ready, I'll request review from you.

[prasanna-anchorage]

only real blocker is the compilation being blocked by the upstream solana-parser changes. I used Claude fairly heavily to track down corner cases I didn't immediately see beyond compiling and trying few things.

I agree with this assessment and copying as-is

What's strong

Crash-safety coverage is thorough. The 50/50 valid-discriminator / random-data split in fuzz_idl_parsing_never_panics is a well-chosen design — it forces the fuzzer into argument-decoding code paths, not just discriminator matching. The same pattern is applied consistently across 4 property tests and the pipeline layer.

The roundtrip tests are well-structured. Each concrete test in fuzz_idl_parsing.rs:267-556 isolates a single type concern (no-args, single primitive, mixed primitives, Option Some/None, Vec, Array, defined struct, multi-instruction dispatch) and verifies both parsing success and value correctness. These serve as specification-by-example.

SizeGuard boundary testing is excellent. Both the proptest (fuzz_size_guard_vec_length_prefix) and concrete tests (size_guard_huge_vec_length_prefix_is_rejected_cleanly, size_guard_vec_u64_over_budget) cover the DoS-mitigation path. The budget math is documented inline.

Real-IDL testing against 15 production IDLs via fuzz_all_idls.sh is a strong regression gate. The script is well-documented, builds once to avoid recompilation, and presents tabular output.

Pipeline integration tests in pipeline_integration.rs correctly verify the full stack (IdlRegistry wiring, visualizer dispatch, field layout) — not just the parser in isolation.

Strategy composition is clean. arb_idl_and_valid_bytes() demonstrates correct use of prop_flat_map with Arc-shared state. The real_idl_valid_data_always_parses_ok test correctly uses TestRunner::run directly for runtime-loaded IDLs.

 Merge blockers

 Blocker 1: Import path mismatch — solana_parser::arb does not exist

 The test files import use solana_parser::arb; but the strategies actually live in a separate crate solana-parser-fuzz-core under pub mod proptest (not arb). The solana_parser crate itself has no
 arb module, no proptest feature, and no re-export.

 This will not resolve by simply merging solana-parser PR #1. PR #1 adds the fuzz-core crate with the strategies, but does not add pub mod arb or any re-export to solana_parser/src/lib.rs.

 Fix required (one of):
 - Option A (recommended): Add a re-export to solana-parser's lib.rs: #[cfg(feature = "proptest")] pub use solana_parser_fuzz_core::proptest as arb; and add a proptest feature to solana_parser's
 Cargo.toml. This preserves the clean solana_parser::arb API the tests expect.
 - Option B: Change the test Cargo.toml to depend on solana-parser-fuzz-core directly and rewrite all imports from solana_parser::arb::* to solana_parser_fuzz_core::proptest::*.

 Affected files:
 - tests/fuzz_idl_parsing.rs — line 16: use solana_parser::arb;
 - tests/pipeline_integration.rs — line 22: use solana_parser::arb;
 - Cargo.toml dev-dependencies — features = ["proptest"] on solana_parser (this feature doesn't exist)

 Blocker 2: Compilation errors (9 + 7 errors)

 As a consequence of Blocker 1, both test files produce cascading compilation errors:
 - fuzz_idl_parsing.rs: 9 errors (E0432 unresolved import + 8 E0277 unsized type errors)
 - pipeline_integration.rs: 7 errors (same pattern)

 These block cargo test --all-targets and will fail CI.

 No other hard blockers found beyond the improvement items below.

[prasanna-anchorage]

🚢 with some minor nits