## Changes
`TestAccFilerWorkspaceFilesExtensionsErrorsOnDupName` recently started
failing in our nightlies because the upstream `import` API was changed
to [prohibit conflicting file
paths](https://docs.databricks.com/en/release-notes/product/2024/august.html#files-can-no-longer-have-identical-names-in-workspace-folders).
Because existing conflicting file paths can still be grandfathered in,
we need to retain coverage for the test. To do this, this PR:
1. Removes the failing
`TestAccFilerWorkspaceFilesExtensionsErrorsOnDupName`
2. Add an equivalent unit test with the `list` and `get-status` API
calls mocked.
## Changes
By default, construct a read/write instance. If constructed in read-only
mode, the underlying filer is wrapped in a readahead cache.
## Tests
* Filer integration tests pass.
* Manual test that caching is enabled when running on WSFS.
## Changes
The reason this readahead cache exists is that we frequently need to
recursively find all files in the bundle root directory, especially for
sync include and exclude processing. By caching the response for every
file/directory and frontloading the latency cost of these calls, we
significantly improve performance and eliminate redundant operations.
## Tests
* [ ] Working on unit tests
## Changes
This consolidates the two separate status calls into one.
The extension-aware filer now doesn't need the direct API client anymore
and fully relies on the underlying filer.
## Tests
* Unit tests.
* Ran the filer integration tests manually.
## Changes
This worked fine if the notebooks are located in the filer's root and
didn't if they are nested in a directory.
This change adds test coverage and fixes the underlying issue.
## Tests
Ran integration test manually.
## Changes
This PR adds a filer that'll allow us to read notebooks from the WSFS
using their full paths (with the extension included). The filer relies
on the existing workspace filer (and consequently the workspace
import/export/list APIs).
Using this filer along with a virtual filesystem layer
(https://github.com/databricks/cli/pull/1452/files) will allow us to use
our custom implementation (which preserves the notebook extensions)
rather than the default mount available via DBR when the CLI is run from
DBR.
## Tests
Integration tests.
---------
Co-authored-by: Pieter Noordhuis <pieter.noordhuis@databricks.com>
shreyas-goenka
Pieter Noordhuis