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(I work on code search.) Yeah, sorry about that. We've heard this feedback a lot. There's two reasons why we haven't implemented this. First, content is shared between repositories which makes this harder than before, when it wasn't. Second, we rebuild the index weekly or even more frequently, so the proxy of "when was this added" that was used doesn't work any more. What we would like to use is "when was this blob added to this branch" but that's extremely expensive to retrieve from Git because Git trees don't record it.

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git blame is expensive, especially at scale, on big repos, but the thing to understand is the exact hash something was commmitted at isn't important for time-based indexing. What's wanted is when, ± a few days, something was committed at, which makes for a much cheaper query. (How merges are dealt with might also be material)

Barring that though, the equivalent of a post-commit git hook that updates the DB with 'when this blob was added to this branch' and then run a backfill-enough job.

The easy answer, though, would seem to be keep a copy of last week's index, and run the query twice and figure out a way to efficiently compare results to figure out if something is this week's but not last weeks index.

Also of note, "when was this blob added to this branch" isn't even actually the same as git blame, which means that if a file was touched that matched the search but the latest change to the file doesn't affect the matching line of code, it'd show up as recent, which is not what the user wants.

Does this mean it will not be implemented?

We want to do it right if we do implement it, but I can't promise anything concretely. It's not trivial, unfortunately.

Sorting the code search results by date has often been my only guide in a breadth-first search, to find out how to use an API in a recent state of the ecosystem, that I am working with.

I am working with .NET and .NET has seen lots and lots of changes in the past years. I often have to see the usage of a library in the current form of the .NET ecosystem, instead of say, an outdated .NET Framework project from 5 years ago.

Is there any equivalent for doing such a search in the new Code Search?

maybe lower standards would help - what does doing it not-quite-right-but-in-one-week look like? can mitigate by setting expectations accordingly

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