Alias httpcore imports to httpcore2 in alias_httpx()

[Kludex]

#1077 only aliased httpx imports, but dependencies importing httpcore directly (e.g. custom transports catching low-level exceptions) were still resolving to the old package. alias_httpx() now also makes import httpcore resolve to httpcore2, with the same submodule handling and already-imported guard.

AI Disclaimer

This PR was developed with the assistance of either Claude or Codex. I've reviewed and verified the changes.

[github-actions]

Docs preview:

[codspeed-hq]

Merging this PR will not alter performance

✅ 15 untouched benchmarks
⏩ 7 skipped benchmarks¹

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_{Comparing alias-httpcore (a7e9be0) with main (c6028d9)}

Footnotes

1. 7 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[cubic-dev-ai]

1 issue found across 3 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/httpx2/httpx2/_alias.py">

<violation number="1" location="src/httpx2/httpx2/_alias.py:53">
P3: The docstring says dependencies importing `httpcore` share `httpx2` classes, but this alias exposes `httpcore2` classes instead. Describing the two package-specific targets would avoid misleading callers about which low-level exception and type hierarchy they receive.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

P3: The docstring says dependencies importing httpcore share httpx2 classes, but this alias exposes httpcore2 classes instead. Describing the two package-specific targets would avoid misleading callers about which low-level exception and type hierarchy they receive.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/httpx2/httpx2/_alias.py, line 53:

<comment>The docstring says dependencies importing `httpcore` share `httpx2` classes, but this alias exposes `httpcore2` classes instead. Describing the two package-specific targets would avoid misleading callers about which low-level exception and type hierarchy they receive.</comment>

<file context>
@@ -30,29 +35,34 @@ def find_spec(
 
     Intended for applications migrating from `httpx`, so that dependencies still
-    importing `httpx` share the `httpx2` classes. Libraries should never call this.
+    importing `httpx` or `httpcore` share the `httpx2` classes. Libraries should never call this.
 
-    Must be called before anything imports `httpx`. Calling it again is a no-op.
</file context>