[core] Use uv for the ESP-IDF Python environment when available (#18838)

esphome/espidf/framework.py

@@ -1053,15 +1053,28 @@ def _check_esp_idf_python_env_install(
             constraint_file_path,
         )
 
-        cmd_pip_install = [
-            str(env_python_path),
-            "-m",
-            "pip",
-            "install",
-            "--upgrade",
-            "--constraint",
-            constraint_file_path,
-        ]
+        # uv (much faster than pip) when available, e.g. in the docker image
+        if uv_path := shutil.which("uv"):
+            cmd_pip_install = [
+                uv_path,
+                "pip",
+                "install",
+                "--python",
+                str(env_python_path),
+                "--upgrade",
+                "--constraint",
+                str(constraint_file_path),
+            ]
+        else:
+            cmd_pip_install = [
+                str(env_python_path),
+                "-m",
+                "pip",
+                "install",
+                "--upgrade",
+                "--constraint",
+                str(constraint_file_path),
+            ]
 
         _LOGGER.info("Installing ESP-IDF %s Python dependencies ...", version)
         cmd = cmd_pip_install + [
@@ -1135,6 +1148,8 @@ def check_esp_idf_install(
     env = {}
     env["IDF_TOOLS_PATH"] = str(get_idf_tools_path())
     env["IDF_PATH"] = ""
+    # uv defaults to 3 HTTP retries; match the pioarduino penv's bump to 10
+    env["UV_HTTP_RETRIES"] = os.environ.get("UV_HTTP_RETRIES", "10")
 
     # An explicit ESPHOME_IDF_DEFAULT_TARGETS wins over the caller's
     # per-variant request (builder-image pre-warm); otherwise the caller's

tests/unit_tests/test_espidf_framework.py

@@ -520,6 +520,33 @@ def test_check_esp_idf_install_feature_failure(espidf_mocks: SimpleNamespace) ->
         check_esp_idf_install(_IDF_VERSION, force=True, features=["fb"])
 
 
+def test_python_deps_use_uv_when_available(
+    espidf_mocks: SimpleNamespace, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """The python env installs go through uv when on the PATH, pip otherwise."""
+    monkeypatch.delenv("UV_HTTP_RETRIES", raising=False)
+    with patch(
+        "esphome.espidf.framework.shutil.which",
+        # Keyed on the name: the same which() also probes the default tools
+        side_effect=lambda name: "/usr/bin/uv" if name == "uv" else None,
+    ):
+        check_esp_idf_install(_IDF_VERSION, force=True, features=["fb"])
+    upgrade_call, feature_call = espidf_mocks.run_ok.call_args_list[1:3]
+    upgrade_cmd, feature_cmd = upgrade_call.args[0], feature_call.args[0]
+    assert upgrade_cmd[:3] == ["/usr/bin/uv", "pip", "install"]
+    assert "--python" in upgrade_cmd
+    assert feature_cmd[:3] == ["/usr/bin/uv", "pip", "install"]
+    assert upgrade_call.kwargs["env"]["UV_HTTP_RETRIES"] == "10"
+
+    espidf_mocks.run_ok.reset_mock()
+    monkeypatch.setenv("UV_HTTP_RETRIES", "3")  # an explicit user value wins
+    with patch("esphome.espidf.framework.shutil.which", return_value=None):
+        check_esp_idf_install(_IDF_VERSION, force=True, features=["fb"])
+    upgrade_call = espidf_mocks.run_ok.call_args_list[1]
+    assert upgrade_call.args[0][1:4] == ["-m", "pip", "install"]
+    assert upgrade_call.kwargs["env"]["UV_HTTP_RETRIES"] == "3"
+
+
 def _mark_installed() -> None:
     """Create the extracted marker and python-env interpreter so the install
     check takes the already-installed path rather than force-installing."""