Add system install test for macOS x86_64 (#2459)

Adds binary builds for x86_64 macOS and a corresponding test

Author: zanieb

.github/workflows/ci.yml

@@ -157,7 +157,7 @@ jobs:
   build-binary-macos-aarch64:
     runs-on:
       labels: macos-14
-    name: "build binary | macos"
+    name: "build binary | macos aarch64"
     steps:
       - uses: actions/checkout@v4
 
@@ -174,6 +174,26 @@ jobs:
           path: ./target/debug/uv
           retention-days: 1
 
+  build-binary-macos-x86_64:
+    runs-on:
+      labels: macos-latest-large
+    name: "build binary | macos x86_64"
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: rui314/setup-mold@v1
+
+      - uses: Swatinem/rust-cache@v2
+      - name: "Build"
+        run: cargo build
+
+      - name: "Upload binary"
+        uses: actions/upload-artifact@v4
+        with:
+          name: uv-macos-x86_64-${{ github.sha }}
+          path: ./target/debug/uv
+          retention-days: 1
+
   build-binary-windows:
     runs-on:
       labels: windows-latest-large
@@ -345,9 +365,9 @@ jobs:
       - name: "Validate global Python install"
         run: python3 scripts/check_system_python.py --uv ./uv --externally-managed
 
-  system-test-macos:
+  system-test-macos-aarch64:
     needs: build-binary-macos-aarch64
-    name: "check system | python on macos"
+    name: "check system | python on macos aarch64"
     runs-on: macos-14
     steps:
       - uses: actions/checkout@v4
@@ -364,10 +384,35 @@ jobs:
         run: chmod +x ./uv
 
       - name: "Print Python path"
-        run: echo $(which python3.11)
+        run: echo $(which python3)
+
+      - name: "Validate global Python install"
+        run: python3 scripts/check_system_python.py --uv ./uv
+
+  system-test-macos-x86_64:
+    needs: build-binary-macos-x86_64
+    name: "check system | python on macos x86_64"
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      # We test with GitHub's Python as a regression test for
+      # https://github.com/astral-sh/uv/issues/2450
+      - uses: actions/setup-python@v5
+
+      - name: "Download binary"
+        uses: actions/download-artifact@v4
+        with:
+          name: uv-macos-x86_64-${{ github.sha }}
+
+      - name: "Prepare binary"
+        run: chmod +x ./uv
+
+      - name: "Print Python path"
+        run: echo $(which python3)
 
       - name: "Validate global Python install"
-        run: python3.11 scripts/check_system_python.py --uv ./uv
+        run: python3 scripts/check_system_python.py --uv ./uv
 
   system-test-windows-python-310:
     needs: build-binary-windows