Add tests for scm changes for file watchers

Summary:
# Context

We are introducing EdenFS notifications to support scalable and ergonomic file system notifications for EdenFS mounts.

# This Diff

* Tests to validate correct behavior when scm changes (rebase and checkout) occur

# Next Steps

* Fix bug in EdenFS that causes `to` and `from` to be switched in commit transitions.
* After fix deployed - remove work around in edenfs file watcher.

Reviewed By: kavehahmadi60

Differential Revision: D67612766

fbshipit-source-id: e1ec49db93021c804c32f24825331acef1ba2a8b

tests/core/common/io/file_watcher_file_tests.py

@@ -153,10 +153,9 @@ async def run_replace_file_test(
     with open(path, "a"):
         pass
 
-    # By getting files here, we clear the log of the previous file watcher events
-    # including the create event for 'def'; this also removes the directory modify event
-    # that we would normally expect to see when creating a file in a directory on native file systems
-    await get_files(buck)
+    # clear log - run build twice
+    await buck.targets("root//:")
+    await buck.targets("root//:")
 
     fromPath = os.path.join(buck.cwd, "files", "abc")
     toPath = os.path.join(buck.cwd, "files", "def")

tests/core/common/io/file_watcher_scm_tests.py

@@ -0,0 +1,187 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+#
+# This source code is licensed under both the MIT license found in the
+# LICENSE-MIT file in the root directory of this source tree and the Apache
+# License, Version 2.0 found in the LICENSE-APACHE file in the root directory
+# of this source tree.
+
+# pyre-strict
+
+
+import os
+import subprocess
+from typing import Tuple
+
+from buck2.tests.core.common.io.file_watcher import (
+    FileWatcherEvent,
+    FileWatcherEventType,
+    FileWatcherKind,
+    FileWatcherProvider,
+    get_file_watcher_events,
+)
+from buck2.tests.core.common.io.file_watcher_tests import (
+    FileSystemType,
+    setup_file_watcher_test,
+    verify_results,
+)
+
+from buck2.tests.e2e_util.api.buck import Buck
+
+
+# Setup repo structure to test these conditions: https://www.internalfb.com/excalidraw/EX346258
+async def setup_file_watcher_scm_test(buck: Buck) -> Tuple[str, str, str, str]:
+    # Run after setup_file_watcher_test to create a simple stack of commits
+    commit_a = subprocess.check_output(["sl", "whereami"], cwd=buck.cwd).decode()
+
+    # Create a file
+    path = os.path.join(buck.cwd, "files", "def")
+    with open(path, "a"):
+        pass
+
+    # Commit it
+    subprocess.run(["sl", "commit", "--addremove", "-m", "commit_b"], cwd=buck.cwd)
+    commit_b = subprocess.check_output(["sl", "whereami"], cwd=buck.cwd).decode()
+
+    # Go back to commit_a
+    subprocess.run(["sl", "co", commit_a], cwd=buck.cwd)
+
+    # Create a file
+    path = os.path.join(buck.cwd, "files", "ghi")
+    with open(path, "a"):
+        pass
+
+    # Commit it
+    subprocess.run(["sl", "commit", "--addremove", "-m", "commit_c"], cwd=buck.cwd)
+    commit_c = subprocess.check_output(["sl", "whereami"], cwd=buck.cwd).decode()
+
+    # Create a file
+    path = os.path.join(buck.cwd, "files", "jkl")
+    with open(path, "a"):
+        pass
+
+    # Commit it
+    subprocess.run(["sl", "commit", "--addremove", "-m", "commit_d"], cwd=buck.cwd)
+    commit_d = subprocess.check_output(["sl", "whereami"], cwd=buck.cwd).decode()
+
+    # clear log- run build twice
+    await buck.targets("root//:")
+    await buck.targets("root//:")
+
+    return commit_a, commit_b, commit_c, commit_d
+
+
+async def run_checkout_mergebase_changes_test(
+    buck: Buck,
+    file_system_type: FileSystemType,
+    file_watcher_provider: FileWatcherProvider,
+) -> None:
+    await setup_file_watcher_test(buck)
+
+    # Create a file
+    path = os.path.join(buck.cwd, "files", "def")
+    with open(path, "a"):
+        pass
+
+    # Commit it
+    subprocess.run(["sl", "commit", "--addremove", "-m", "next"], cwd=buck.cwd)
+    commit_a = subprocess.check_output(["sl", "whereami"], cwd=buck.cwd).decode()
+
+    # Create a file
+    path = os.path.join(buck.cwd, "files", "ghi")
+    with open(path, "a"):
+        pass
+
+    # Commit it
+    subprocess.run(["sl", "commit", "--addremove", "-m", "next"], cwd=buck.cwd)
+    commit_b = subprocess.check_output(["sl", "whereami"], cwd=buck.cwd).decode()
+
+    # Go back to the previous commit
+    subprocess.run(["sl", "co", commit_a], cwd=buck.cwd)
+
+    is_fresh_instance, _ = await get_file_watcher_events(buck)
+    if file_watcher_provider in [
+        FileWatcherProvider.FS_HASH_CRAWLER,
+        FileWatcherProvider.RUST_NOTIFY,
+    ]:
+        # Stats only records the first 100 events (https://fburl.com/code/x9esqun4)
+        # so we can't verify the results when making commit transitions
+        assert not is_fresh_instance
+    else:
+        # We might have some events even for a fresh instance, so we ignore
+        assert is_fresh_instance
+
+    # Go back to the next commit
+    subprocess.run(["sl", "co", commit_b], cwd=buck.cwd)
+
+    is_fresh_instance, _ = await get_file_watcher_events(buck)
+    if file_watcher_provider in [
+        FileWatcherProvider.FS_HASH_CRAWLER,
+        FileWatcherProvider.RUST_NOTIFY,
+    ]:
+        assert not is_fresh_instance
+    else:
+        assert is_fresh_instance
+
+
+async def run_checkout_wtih_mergebase_test(
+    buck: Buck,
+    file_system_type: FileSystemType,
+    file_watcher_provider: FileWatcherProvider,
+) -> None:
+    await setup_file_watcher_test(buck)
+    [_, _, commit_c, _] = await setup_file_watcher_scm_test(buck)
+
+    # Go back to commit_c
+    subprocess.run(["sl", "co", commit_c], cwd=buck.cwd)
+
+    if file_watcher_provider != FileWatcherProvider.RUST_NOTIFY:
+        required = [
+            FileWatcherEvent(
+                FileWatcherEventType.DELETE, FileWatcherKind.FILE, "root//files/jkl"
+            )
+        ]
+    else:
+        required = [
+            FileWatcherEvent(
+                FileWatcherEventType.MODIFY, FileWatcherKind.FILE, "root//files/jkl"
+            )
+        ]
+
+    is_fresh_instance, results = await get_file_watcher_events(buck)
+    assert not is_fresh_instance
+    verify_results(results, required)
+
+
+async def run_rebase_wtih_mergebase_test(
+    buck: Buck,
+    file_system_type: FileSystemType,
+    file_watcher_provider: FileWatcherProvider,
+) -> None:
+    await setup_file_watcher_test(buck)
+    [_, commit_b, commit_c, _] = await setup_file_watcher_scm_test(buck)
+
+    # Rebaase C->D from A to B
+    subprocess.run(["sl", "rebase", "-s", commit_c, "-d", commit_b], cwd=buck.cwd)
+
+    is_fresh_instance, results = await get_file_watcher_events(buck)
+    if file_system_type == FileSystemType.NATIVE:
+        # Watchman is flakey on native file systems
+        if file_watcher_provider != FileWatcherProvider.WATCHMAN:
+            assert not is_fresh_instance
+    else:
+        assert is_fresh_instance
+
+
+async def run_restack_wtih_mergebase_test(
+    buck: Buck,
+    file_system_type: FileSystemType,
+    file_watcher_provider: FileWatcherProvider,
+) -> None:
+    await setup_file_watcher_test(buck)
+    [commit_a, _, _, commit_d] = await setup_file_watcher_scm_test(buck)
+
+    # Rebaase D from C to A
+    subprocess.run(["sl", "rebase", "-s", commit_d, "-d", commit_a], cwd=buck.cwd)
+
+    is_fresh_instance, results = await get_file_watcher_events(buck)
+    assert not is_fresh_instance

tests/core/io/test_edenfs.py

@@ -20,6 +20,12 @@
     run_rename_file_test,
     run_replace_file_test,
 )
+from buck2.tests.core.common.io.file_watcher_scm_tests import (
+    run_checkout_mergebase_changes_test,
+    run_checkout_wtih_mergebase_test,
+    run_rebase_wtih_mergebase_test,
+    run_restack_wtih_mergebase_test,
+)
 from buck2.tests.core.common.io.file_watcher_tests import FileSystemType
 
 from buck2.tests.e2e_util.api.buck import Buck
@@ -81,3 +87,31 @@ async def test_edenfs_rename_directory(buck: Buck) -> None:
     await run_rename_directory_test(
         buck, FileSystemType.EDEN_FS, FileWatcherProvider.EDEN_FS
     )
+
+
+@buck_test(setup_eden=True)
+async def test_edenfs_checkout_mergebase_changes(buck: Buck) -> None:
+    await run_checkout_mergebase_changes_test(
+        buck, FileSystemType.EDEN_FS, FileWatcherProvider.EDEN_FS
+    )
+
+
+@buck_test(setup_eden=True)
+async def test_edenfs_checkout_with_mergebase(buck: Buck) -> None:
+    await run_checkout_wtih_mergebase_test(
+        buck, FileSystemType.EDEN_FS, FileWatcherProvider.EDEN_FS
+    )
+
+
+@buck_test(setup_eden=True)
+async def test_edenfs_rebase_with_mergebase(buck: Buck) -> None:
+    await run_rebase_wtih_mergebase_test(
+        buck, FileSystemType.EDEN_FS, FileWatcherProvider.EDEN_FS
+    )
+
+
+@buck_test(setup_eden=True)
+async def test_edenfs_restack_with_mergebase(buck: Buck) -> None:
+    await run_restack_wtih_mergebase_test(
+        buck, FileSystemType.EDEN_FS, FileWatcherProvider.EDEN_FS
+    )

tests/core/io/test_fs_hash_crawler.py

@@ -21,6 +21,12 @@
     run_rename_file_test,
     run_replace_file_test,
 )
+from buck2.tests.core.common.io.file_watcher_scm_tests import (
+    run_checkout_mergebase_changes_test,
+    run_checkout_wtih_mergebase_test,
+    run_rebase_wtih_mergebase_test,
+    run_restack_wtih_mergebase_test,
+)
 from buck2.tests.core.common.io.file_watcher_tests import FileSystemType
 
 from buck2.tests.e2e_util.api.buck import Buck
@@ -82,3 +88,31 @@ async def test_fs_hash_cralwer_rename_directory(buck: Buck) -> None:
     await run_rename_directory_test(
         buck, FileSystemType.NATIVE, FileWatcherProvider.FS_HASH_CRAWLER
     )
+
+
+@buck_test(setup_eden=False)
+async def test_fs_hash_cralwer_checkout_mergebase_changes(buck: Buck) -> None:
+    await run_checkout_mergebase_changes_test(
+        buck, FileSystemType.NATIVE, FileWatcherProvider.FS_HASH_CRAWLER
+    )
+
+
+@buck_test(setup_eden=False)
+async def test_fs_hash_cralwer_checkout_with_mergebase(buck: Buck) -> None:
+    await run_checkout_wtih_mergebase_test(
+        buck, FileSystemType.NATIVE, FileWatcherProvider.FS_HASH_CRAWLER
+    )
+
+
+@buck_test(setup_eden=False)
+async def test_fs_hash_cralwer_rebase_with_mergebase(buck: Buck) -> None:
+    await run_rebase_wtih_mergebase_test(
+        buck, FileSystemType.NATIVE, FileWatcherProvider.FS_HASH_CRAWLER
+    )
+
+
+@buck_test(setup_eden=False)
+async def test_fs_hash_cralwer_restack_with_mergebase(buck: Buck) -> None:
+    await run_restack_wtih_mergebase_test(
+        buck, FileSystemType.NATIVE, FileWatcherProvider.FS_HASH_CRAWLER
+    )

tests/core/io/test_notify.py

@@ -21,6 +21,12 @@
     run_rename_file_test,
     run_replace_file_test,
 )
+from buck2.tests.core.common.io.file_watcher_scm_tests import (
+    run_checkout_mergebase_changes_test,
+    run_checkout_wtih_mergebase_test,
+    run_rebase_wtih_mergebase_test,
+    run_restack_wtih_mergebase_test,
+)
 from buck2.tests.core.common.io.file_watcher_tests import FileSystemType
 
 from buck2.tests.e2e_util.api.buck import Buck
@@ -82,3 +88,31 @@ async def test_notify_rename_directory(buck: Buck) -> None:
     await run_rename_directory_test(
         buck, FileSystemType.NATIVE, FileWatcherProvider.RUST_NOTIFY
     )
+
+
+@buck_test(setup_eden=False)
+async def test_notify_checkout_mergebase_changes(buck: Buck) -> None:
+    await run_checkout_mergebase_changes_test(
+        buck, FileSystemType.NATIVE, FileWatcherProvider.RUST_NOTIFY
+    )
+
+
+@buck_test(setup_eden=False)
+async def test_notify_checkout_with_mergebase(buck: Buck) -> None:
+    await run_checkout_wtih_mergebase_test(
+        buck, FileSystemType.NATIVE, FileWatcherProvider.RUST_NOTIFY
+    )
+
+
+@buck_test(setup_eden=False)
+async def test_notify_rebase_with_mergebase(buck: Buck) -> None:
+    await run_rebase_wtih_mergebase_test(
+        buck, FileSystemType.NATIVE, FileWatcherProvider.RUST_NOTIFY
+    )
+
+
+@buck_test(setup_eden=False)
+async def test_notify_restack_with_mergebase(buck: Buck) -> None:
+    await run_restack_wtih_mergebase_test(
+        buck, FileSystemType.NATIVE, FileWatcherProvider.RUST_NOTIFY
+    )