Create one database connection per thread

[tkrabel]

Description

Addresses #714 (comment), using a threadlocal to create data base connections.

Fixes #713

Checklist (delete if not relevant):

• I have added tests that prove my fix is effective or that my feature works
• I have updated CHANGELOG.md
• I have made corresponding changes to user documentation for new features
• I have made corresponding changes to library documentation for API changes

[lieryan]

Hi @tkrabel, thanks for making this PR, there's one issue with the code currently as they are. Once they are fixed, I think it should be ready to go.

[lieryan]

IIUC, creating the thread_local at the module-level like this would mean that all instances of autoimports would share the same database and database connection, even though they belong to different instances of AutoImport and more importantly that they belong to different Projects:

project_a = Project("/path/to/project/a")
project_b = Project("/path/to/project/b")
ai_a = AutoImport(project_a, ...)
ai_b = AutoImport(project_b, ...)

assert ai_a.connection is not ai_b.connection

That does not look correct to me. I think this can be avoided by moving thread_local to be an instance variable initialized in AutoImport.__init__().

[tkrabel]

Thanks for pointing that our! You're right. I moved the thread local to the __init__ and wrote a test that verifies the following passes:

# Test connections
from rope.base.project import Project
from rope.contrib.autoimport.sqlite import AutoImport

ai1 = AutoImport(Project(".."))
ai2 = AutoImport(Project("."))
ai3 = AutoImport(Project("."))

assert ai1.connection is not ai2.connection
assert ai1.connection is not ai3.connection

[lieryan]

Looks good to me, thanks for the contribution @tkrabel.

@all-contributors add @tkrabel for code contribution

[allcontributors]

@lieryan

I couldn't determine any contributions to add, did you specify any contributions?
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I've put up a pull request to add @tkrabel! 🎉