Raise minimum python version to 3.9

Qiskit 1.2.0 was the final minor version release of qiskit with Python
3.8 support. As Python 3.8 is going EoL before the next Qiskit minor
release 1.3.0 we can drop support for running with 3.8 on the main
branch now. This commit makes that change and updates everything using
python 3.8 currently to use our new minimum instead.

.github/workflows/coverage.yml

@@ -22,7 +22,7 @@ jobs:
       - uses: actions/setup-python@v5
         name: Install Python
         with:
-          python-version: '3.8'
+          python-version: '3.11'
 
       - name: Install Rust toolchain
         uses: dtolnay/rust-toolchain@stable

.github/workflows/randomized_tests.yml

@@ -13,7 +13,7 @@ jobs:
       - uses: actions/setup-python@v5
         name: Install Python
         with:
-          python-version: '3.8'
+          python-version: '3.11'
       - name: Install dependencies
         run: |
           python -m pip install -U pip setuptools wheel

.github/workflows/tests.yml

@@ -18,7 +18,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        # Normally we test min and max version but we can't run python 3.8 or
+        # Normally we test min and max version but we can't run python
         # 3.9 on arm64 until actions/setup-python#808 is resolved
         python-version: ["3.10", "3.12"]
     steps:

.github/workflows/wheels.yml

@@ -41,35 +41,6 @@ jobs:
         with:
           path: ./wheelhouse/*.whl
           name: wheels-${{ matrix.os }}
-  build_wheels_macos_arm_py38:
-    name: Build wheels on macOS arm
-    runs-on: ${{ matrix.os }}
-    strategy:
-      fail-fast: false
-      matrix:
-        os: [macos-12]
-    steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
-        name: Install Python
-        with:
-          python-version: '3.10'
-      - uses: dtolnay/rust-toolchain@stable
-        with:
-          components: llvm-tools-preview
-      - name: Build wheels
-        uses: pypa/[email protected]
-        env:
-          CIBW_BEFORE_ALL: rustup target add aarch64-apple-darwin
-          CIBW_BUILD: cp38-macosx_universal2 cp38-macosx_arm64
-          CIBW_ARCHS_MACOS: arm64 universal2
-          CIBW_ENVIRONMENT: >-
-            CARGO_BUILD_TARGET="aarch64-apple-darwin"
-            PYO3_CROSS_LIB_DIR="/Library/Frameworks/Python.framework/Versions/$(python -c 'import sys; print(str(sys.version_info[0])+"."+str(sys.version_info[1]))')/lib/python$(python -c 'import sys; print(str(sys.version_info[0])+"."+str(sys.version_info[1]))')"
-      - uses: actions/upload-artifact@v4
-        with:
-          path: ./wheelhouse/*.whl
-          name: wheels-${{ matrix.os }}-arm
   build_wheels_32bit:
     name: Build wheels 32bit
     runs-on: ${{ matrix.os }}
@@ -100,7 +71,7 @@ jobs:
     environment: release
     permissions:
       id-token: write
-    needs: ["build_wheels", "build_wheels_32bit", "build_wheels_macos_arm_py38"]
+    needs: ["build_wheels", "build_wheels_32bit"]
     steps:
       - uses: actions/download-artifact@v4
         with:

Cargo.toml

@@ -29,7 +29,7 @@ thiserror = "1.0"
 # distributions).  We only activate that feature when building the C extension module; we still need
 # it disabled for Rust-only tests to avoid linker errors with it not being loaded.  See
 # https://pyo3.rs/main/features#extension-module for more.
-pyo3 = { version = "0.21.2", features = ["abi3-py38"] }
+pyo3 = { version = "0.21.2", features = ["abi3-py39"] }
 
 # These are our own crates.
 qiskit-accelerate = { path = "crates/accelerate" }

azure-pipelines.yml

@@ -37,12 +37,12 @@ parameters:
   - name: "supportedPythonVersions"
     displayName: "All supported versions of Python"
     type: object
-    default: ["3.8", "3.9", "3.10", "3.11", "3.12"]
+    default: ["3.9", "3.10", "3.11", "3.12"]
 
   - name: "minimumPythonVersion"
     displayName: "Minimum supported version of Python"
     type: string
-    default: "3.8"
+    default: "3.9"
 
   - name: "maximumPythonVersion"
     displayName: "Maximum supported version of Python"

pyproject.toml

@@ -5,7 +5,7 @@ build-backend = "setuptools.build_meta"
 [project]
 name = "qiskit"
 description = "An open-source SDK for working with quantum computers at the level of extended quantum circuits, operators, and primitives."
-requires-python = ">=3.8"
+requires-python = ">=3.9"
 license = {text = "Apache 2.0"}
 authors = [
     { name = "Qiskit Development Team", email = "[email protected]" },
@@ -27,7 +27,6 @@ classifiers = [
     "Operating System :: Microsoft :: Windows",
     "Operating System :: POSIX :: Linux",
     "Programming Language :: Python :: 3 :: Only",
-    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
@@ -134,12 +133,12 @@ include = ["qiskit", "qiskit.*"]
 
 [tool.black]
 line-length = 100
-target-version = ['py38', 'py39', 'py310', 'py311']
+target-version = ['py39', 'py310', 'py311']
 
 [tool.cibuildwheel]
 manylinux-x86_64-image = "manylinux2014"
 manylinux-i686-image = "manylinux2014"
-skip = "pp* cp36-* cp37-* *musllinux* *win32 *i686 cp38-macosx_arm64"
+skip = "pp* cp36-* cp37-* cp38-* *musllinux* *win32 *i686 cp38-macosx_arm64"
 test-skip = "*win32 *linux_i686"
 test-command = "python {project}/examples/python/stochastic_swap.py"
 # We need to use pre-built versions of Numpy and Scipy in the tests; they have a
@@ -191,7 +190,7 @@ extension-pkg-allow-list = [
     "tweedledum",
 ]
 load-plugins = ["pylint.extensions.docparams", "pylint.extensions.docstyle"]
-py-version = "3.8"  # update it when bumping minimum supported python version
+py-version = "3.9"  # update it when bumping minimum supported python version
 
 [tool.pylint.basic]
 good-names = ["a", "b", "i", "j", "k", "d", "n", "m", "ex", "v", "w", "x", "y", "z", "Run", "_", "logger", "q", "c", "r", "qr", "cr", "qc", "nd", "pi", "op", "b", "ar", "br", "p", "cp", "ax", "dt", "__unittest", "iSwapGate", "mu"]

releasenotes/notes/py3.9-min-now-c9781484a0eb288e.yaml

@@ -0,0 +1,6 @@
+---
+upgrade:
+  - |
+    The minimum supported version of Python is now 3.9, this has been raised
+    from the previous minimum support version of 3.8. This change was necessary
+    because the upstream cPython project no longer supports Python 3.8.

test/python/circuit/test_gate_definitions.py

@@ -250,6 +250,25 @@ def test_inverse(self, class_name, gate_class):
         from qiskit.quantum_info.operators.predicates import is_identity_matrix
 
         self.assertTrue(is_identity_matrix(Operator(gate).dot(gate.inverse()).data))
+        print(gate_class)
+        print(gate)
+        import pprint
+        print("Forward")
+        for inst in gate.definition:
+            if inst.matrix is None:
+                print(inst.operation.definition)
+        pprint.pprint([inst.matrix for inst in gate.definition])
+        for inst in gate.definition.inverse():
+            if inst.matrix is None:
+                print(inst.operation.definition)
+        print("Inverse")
+        pprint.pprint([inst.operation for inst in gate.definition.inverse()])
+
+        print("Converted")
+        from qiskit.converters import circuit_to_instruction
+        pprint.pprint([inst.operation for inst in circuit_to_instruction(gate.definition).definition])
+        print("inverse")
+        pprint.pprint([inst.operation for inst in circuit_to_instruction(gate.definition.inverse()).definition])
 
         if gate.definition is not None:
             self.assertTrue(is_identity_matrix(Operator(gate).dot(gate.definition.inverse()).data))

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 minversion = 4.0
-envlist = py38, py39, py310, py311, py312, lint-incr
+envlist = py39, py310, py311, py312, lint-incr
 isolated_build = true
 
 [testenv]
@@ -15,7 +15,7 @@ setenv =
   QISKIT_SUPRESS_PACKAGING_WARNINGS=Y
   QISKIT_TEST_CAPTURE_STREAMS=1
   QISKIT_PARALLEL=FALSE
-passenv = 
+passenv =
   RUSTUP_TOOLCHAIN
   RAYON_NUM_THREADS
   OMP_NUM_THREADS