fix(test): open .test files in binary mode to fix Windows e2e_test runner

[chiangchenghsin-hash]

Summary

Fixes the Windows e2e_test runner which has never worked on MSVC — all .test files fail to parse on Windows due to a tellg()/seekg() offset bug in text mode.

Root Cause

MSVC's text mode (ifstream::open(path)) adds an internal \r\n → \n translation layer. When getline() reads an LF-only file, tellg() returns a position that is 1 byte ahead per line (treating \n as the second byte of a \r\n pair). After extractTextBeforeNextStatement() calls setCursorToPreviousLine() → seekg(previousFilePosition), the next getline() reads from a wrong byte offset, causing subsequent statements to be parsed as garbage characters (e.g., ";" instead of "---- ok").

Fix (2 files, 10 lines)

test/test_runner/test_parser.cpp

// Before:
fileStream.open(path);

// After:
fileStream.open(path, std::ios::binary);

Binary mode makes tellg()/seekg() work with exact byte positions on all platforms.

test/include/test_runner/test_parser.h

// Before:
bool nextLine() {
    previousFilePosition = fileStream.tellg();
    return static_cast<bool>(getline(fileStream, line));
}

// After:
bool nextLine() {
    previousFilePosition = fileStream.tellg();
    bool result = static_cast<bool>(getline(fileStream, line));
    // Strip trailing '\r' (CRLF line endings). When the file is opened in
    // binary mode, getline keeps '\r'; this keeps both LF and CRLF test
    // files parseable identically on all platforms.
    if (result && !line.empty() && line.back() == '\r') {
        line.pop_back();
    }
    return result;
}

Verification

Tested on Windows 11 x64 MSVC 19.50 with 11 upstream algo e2e tests:

Test suite	Tests	Result
louvain (6)	Two3Clique, Basic, Two4Clique, OnlyNodes, SimplePath, Single6Clique	✅ ALL PASS
page_rank (1)	PageRank1	✅ PASS
leiden (4)	LeidenBasic, LeidenAlias, LeidenDisconnected, LeidenHeterogeneous	✅ ALL PASS

Before fix: All tests threw Invalid statement on the first multi-line CREATE statement.

After fix: 11/11 pass, identical behavior to Linux.

Impact

• Platform-agnostic: The fix works on Linux/macOS too (binary mode + strip \r is a no-op when files have LF endings)
• No test changes needed: All existing .test files work as-is
• Enables Windows CI: Upstream CI currently only runs e2e tests on Linux; this fix makes Windows e2e testing viable

[adsharma]

Windows tests run every night (but not on every PR). They seem to be passing.

https://github.com/LadybugDB/ladybug/actions/runs/30789230797/job/91609180138

[chiangchenghsin-hash]

Good point — the nightly Windows CI runs ctest --test-dir build/release/test which is the GTest C++ test suite. That's different from the .test file runner (e2e_test.exe) which parses the declarative .test files.

The .test file-based extension tests only run in the minimal-linux-extension-test job (Linux only). The bug I fixed is specifically in the .test file parser (test_parser.cpp's openFile() / setCursorToPreviousLine() / nextLine()) — it's invisible to the GTest path.

So the nightly Windows tests pass because they never exercise the .test file parser. If you ever enable .test-based extension tests on Windows (e.g. by running e2e_test.exe with E2E_TEST_FILES_DIRECTORY=extension), you'd hit the Invalid statement error without this fix.

That said, the fix is harmless on Linux/macOS too (binary mode + strip \r is a no-op for LF files), so it's a no-risk improvement either way.

[chiangchenghsin-hash]

To be more precise with evidence — here's exactly what the Windows CI step runs (.github/workflows/ci-workflow.yml, lines in the Test step):

if [ "$RUNNER_OS" = "Windows" ]; then
    make test-build-release
    ctest --test-dir build/release/test --output-on-failure -j "${TEST_JOBS}"
    exit   # ← exits here, never reaches the e2e_test path
fi

And the .test file runner is only used in minimal-linux-extension-test:

minimal-linux-extension-test:
    runs-on: ubuntu-latest          # ← Linux only
    if: ${{ github.event_name != 'workflow_dispatch' || github.event.inputs.platform == 'linux' }}

So on Windows, ctest runs GTest-based C++ unit tests (like e2e_test.exe's gtest_discover_tests), but the .test files under extension/*/test/test_files/ are never parsed because E2E_TEST_FILES_DIRECTORY is not set and the extension-test make target is not called on Windows.

The specific failure mode: when e2e_test.exe reads a .test file on Windows, tellg() returns byte offsets that are 1 per line ahead of the actual file position (MSVC text mode \r\n translation). After setCursorToPreviousLine() calls seekg(previousFilePosition), the next getline() reads from a wrong offset — typically landing on a ; or other character mid-line, throwing Invalid statement. The fix (ios::binary + strip \r) makes tellg()/seekg() byte-accurate on all platforms.

If you'd like, I can add a Windows extension test step to the CI workflow as a follow-up PR.

[chiangchenghsin-hash]

For concrete evidence, here's the actual failure output I captured while debugging on Windows 11 x64 MSVC 19.50:

# Before fix — running e2e_test.exe with louvain.test:
DEBUG parseStatement loop: type=27 line=[-STATEMENT CREATE NODE TABLE Node(id INT64 PRIMARY KEY);]
DEBUG STATEMENT: line=[-STATEMENT CREATE NODE TABLE Node(id INT64 PRIMARY KEY);]
DEBUG STATEMENT after extract: line=[---- ok] query=[CREATE NODE TABLE Node(id INT64 PRIMARY KEY);]
DEBUG parseStatement loop: type=28 line=[;]
Error: Invalid statement [C:/.../louvain.test:;]

The type=28 is TokenType::_SKIP_LINE. After extractTextBeforeNextStatement() calls setCursorToPreviousLine(), the stream re-reads from a wrong byte offset — landing on ; (the semicolon inside PRIMARY KEY);) instead of ---- ok.

The root cause: MSVC text mode tellg() on an LF-only file returns previousFilePosition that's 1 byte ahead per line read. The file is only 55 bytes total, but tellg() returns 64 after reading 6 lines. seekg(55) then reads from a position past the actual line boundary.

# After fix (binary mode + strip \r):
[  PASSED  ] leiden.LeidenBasic (117 ms)
[  PASSED  ] leiden.LeidenAlias (82 ms)
[  PASSED  ] leiden.LeidenDisconnected (110 ms)
[  PASSED  ] leiden_heterogeneous.LeidenHeterogeneous (127 ms)
[  PASSED  ] louvain.Two3Clique (93 ms)
[  PASSED  ] louvain.Basic (97 ms)
[  PASSED  ] louvain.Two4Clique (105 ms)
[  PASSED  ] louvain.OnlyNodes (104 ms)
[  PASSED  ] louvain.SimplePath (90 ms)
[  PASSED  ] louvain.Single6Clique (97 ms)
[  PASSED  ] page_rank.PageRank1 (503 ms)
[  PASSED  ] 11 tests.

All 11 upstream .test files pass on Windows after the fix.