Replace qiskit metapackage with qiskit-terra

.azure/lint-linux.yml

@@ -26,7 +26,6 @@ jobs:
             -c constraints.txt \
             -r requirements.txt \
             -r requirements-dev.txt \
-            ./qiskit_pkg \
             -e .
           # Build and install both qiskit and qiskit-terra so that any optionals
           # depending on `qiskit` will resolve correctly.
@@ -38,7 +37,7 @@ jobs:
           set -e
           source test-job/bin/activate
           echo "Running black, any errors reported can be fixed with 'tox -eblack'"
-          black --check qiskit test tools examples setup.py qiskit_pkg
+          black --check qiskit test tools examples setup.py
           echo "Running rustfmt check, any errors reported can be fixed with 'cargo fmt'"
           cargo fmt --check
         displayName: "Formatting"
@@ -47,7 +46,7 @@ jobs:
           set -e
           source test-job/bin/activate
           echo "Running ruff"
-          ruff qiskit test tools examples setup.py qiskit_pkg/setup.py
+          ruff qiskit test tools examples setup.py
           echo "Running pylint"
           pylint -rn qiskit test tools
           echo "Running Cargo Clippy"

.azure/test-linux.yml

@@ -74,12 +74,11 @@ jobs:
             python -m pip install -U pip
             python -m pip install -U build
             python -m build --sdist .
-            python -m build --sdist qiskit_pkg
             python -m pip install -U \
               -c constraints.txt \
               -r requirements.txt \
               -r requirements-dev.txt \
-              dist/qiskit*.tar.gz
+              dist/qiskit-*.tar.gz
             # Build and install both qiskit and qiskit-terra so that any optionals
             # depending on `qiskit` will resolve correctly.
           displayName: "Install Terra from sdist"
@@ -92,7 +91,6 @@ jobs:
               -c constraints.txt \
               -r requirements.txt \
               -r requirements-dev.txt \
-              ./qiskit_pkg \
               -e .
             # Build and install both qiskit and qiskit-terra so that any optionals
             # depending on `qiskit` will resolve correctly.

.azure/test-macos.yml

@@ -43,7 +43,6 @@ jobs:
             -c constraints.txt \
             -r requirements.txt \
             -r requirements-dev.txt \
-            ./qiskit_pkg \
             -e .
             # Build and install both qiskit and qiskit-terra so that any optionals
             # depending on `qiskit` will resolve correctly.

.azure/test-windows.yml

@@ -42,7 +42,6 @@ jobs:
             -c constraints.txt \
             -r requirements.txt \
             -r requirements-dev.txt \
-            ./qiskit_pkg \
             -e .
           # Build and install both qiskit and qiskit-terra so that any optionals
           # depending on `qiskit` will resolve correctly.

.github/workflows/coverage.yml

@@ -42,7 +42,7 @@ jobs:
         run: python -m pip install -c constraints.txt --upgrade pip setuptools wheel
 
       - name: Build and install qiskit-terra
-        run: python -m pip install -c constraints.txt -e . ./qiskit_pkg
+        run: python -m pip install -c constraints.txt -e .
         env:
           CARGO_INCREMENTAL: 0
           RUSTFLAGS: "-Cinstrument-coverage"

.github/workflows/neko.yml

@@ -16,4 +16,6 @@ jobs:
       - uses: Qiskit/qiskit-neko@main
         with:
           test_selection: terra
-          repo_install_command: "pip install -c constraints.txt ."
+          # We have to forcibly uninstall any old version of qiskit or qiskit-terra during the
+          # changeover, because it's not possible to safely upgrade an existing installation to 1.0.
+          repo_install_command: "pip uninstall qiskit qiskit-terra && pip install -c constraints.txt ."

.github/workflows/slow.yml

@@ -19,7 +19,7 @@ jobs:
           python -m pip install -U pip setuptools wheel
           python -m pip install -U -r requirements.txt -c constraints.txt
           python -m pip install -U -r requirements-dev.txt -c constraints.txt
-          python -m pip install -c constraints.txt -e . ./qiskit_pkg
+          python -m pip install -c constraints.txt -e .
           python -m pip install "qiskit-aer" "z3-solver" "cplex" -c constraints.txt
         env:
           SETUPTOOLS_ENABLE_FEATURES: "legacy-editable"

.github/workflows/wheels.yml

@@ -168,7 +168,7 @@ jobs:
         with:
           packages-dir: wheelhouse/
   sdist:
-    name: Build and publish terra sdist
+    name: Build and publish sdist
     runs-on: ${{ matrix.os }}
     needs: ["upload_shared_wheels"]
     environment: release
@@ -190,31 +190,3 @@ jobs:
         run: python -m build . --sdist
       - name: Publish package distributions to PyPI
         uses: pypa/gh-action-pypi-publish@release/v1
-  metapackage:
-    name: Build and publish terra sdist
-    runs-on: ${{ matrix.os }}
-    needs: ["sdist"]
-    environment: release
-    permissions:
-      id-token: write
-    strategy:
-      fail-fast: false
-      matrix:
-        os: [ubuntu-latest]
-    steps:
-      - uses: actions/checkout@v3
-      - uses: actions/setup-python@v4
-        name: Install Python
-        with:
-          python-version: '3.10'
-      - name: Install deps
-        run: pip install -U build
-      - name: Build packages
-        run: |
-          set -e
-          cd qiskit_pkg
-          python -m build .
-      - name: Publish package distributions to PyPI
-        uses: pypa/gh-action-pypi-publish@release/v1
-        with:
-          packages-dir: qiskit_pkg/dist

releasenotes/notes/terra-nullius-7ef598626d8118c1.yaml

@@ -0,0 +1,29 @@
+---
+critical:
+  - |
+    You cannot upgrade in place to Qiskit 1.0.  You must begin a new virtual environment.
+
+    From Qiskit 1.0, Qiskit is comprised of exactly one Python package: ``qiskit``.  Previously,
+    as a legacy of the "component elements" of early Qiskit, the ``qiskit`` package was a
+    dependency-only "metapackage", and the core code of Qiskit was in a package called ``qiskit-terra``.
+    As Qiskit grew, the other elements split off into their own packages (such as ``qiskit-aer``)
+    until only the core was left in the metapackage.  For Qiskit 1.0, we are removing the metapackage
+    entirely, and replacing it with the actual Qiskit code.
+
+    This means that you cannot upgrade an existing installation to Qiskit 1.0.  Instead, you must
+    create a new Python virtual environment.  Using the built-in ``venv`` module, you can do (Linux
+    and Mac):
+
+    .. code-block:: bash
+
+      # Create the new environment (only once).
+      python -m venv ~/qiskit-1.0-venv
+      # Activate the environment (every session).
+      source ~/qiskit-1.0-venv/bin/activate
+      # Install Qiskit (only once).
+      pip install 'qiskit>=1.0'
+
+    On Windows, replace ``source <venv>/bin/activate`` with ``source <venv>/Scripts/activate``.
+
+    If you are a library author, or have code that depends on Qiskit, you should update any old
+    dependencies on ``qiskit-terra`` to instead depend on ``qiskit``.

setup.py

@@ -56,7 +56,7 @@
 
 
 setup(
-    name="qiskit-terra",
+    name="qiskit",
     version="1.0.0",
     description="Software for developing quantum computing programs",
     long_description=README,

tools/deploy_translatable_strings.sh

@@ -84,8 +84,9 @@ rm -rf \
 echo "+ 'cp' wanted files from source to target"
 # Copy the new rendered files and add them to the commit.
 cp -r "$SOURCE_PO_DIR/." "$TARGET_PO_DIR"
-# Copy files necessary to build the Qiskit metapackage.
-cp "$SOURCE_REPO_ROOT/qiskit_pkg/setup.py" "${TARGET_REPO_ROOT}"
+# Copy files necessary to build the Qiskit package.
+cp "$SOURCE_REPO_ROOT/setup.py" "${TARGET_REPO_ROOT}"
+cp "$SOURCE_REPO_ROOT/pyproject.toml" "${TARGET_REPO_ROOT}"
 cat "$SOURCE_REPO_ROOT/requirements-dev.txt" "$SOURCE_REPO_ROOT/requirements-optional.txt" \
     > "${TARGET_REPO_ROOT}/requirements-dev.txt"
 cp "$SOURCE_REPO_ROOT/constraints.txt" "${TARGET_REPO_ROOT}"

tox.ini

@@ -4,10 +4,6 @@ envlist = py38, py39, py310, py311, py312, lint-incr
 isolated_build = true
 
 [testenv]
-# We pretend that we're not actually installing the package, because we need tox to let us have two
-# packages ('qiskit' and 'qiskit-terra') under test at the same time.  For that, we have to stuff
-# them into 'deps'.
-skip_install = true
 install_command = pip install -c{toxinidir}/constraints.txt -U {opts} {packages}
 setenv =
   VIRTUAL_ENV={envdir}
@@ -22,16 +18,14 @@ deps =
     setuptools_rust  # This is work around for the bug of tox 3 (see #8606 for more details.)
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/requirements-dev.txt
-    -e .
-    -e ./qiskit_pkg
 commands =
   stestr run {posargs}
 
 [testenv:lint]
 basepython = python3
 commands =
-  ruff check qiskit test tools examples setup.py qiskit_pkg
-  black --check {posargs} qiskit test tools examples setup.py qiskit_pkg
+  ruff check qiskit test tools examples setup.py
+  black --check {posargs} qiskit test tools examples setup.py
   pylint -rn qiskit test tools
   # This line is commented out until #6649 merges. We can't run this currently
   # via tox because tox doesn't support globbing
@@ -45,8 +39,8 @@ commands =
 basepython = python3
 allowlist_externals = git
 commands =
-  ruff check qiskit test tools examples setup.py qiskit_pkg
-  black --check {posargs} qiskit test tools examples setup.py qiskit_pkg
+  ruff check qiskit test tools examples setup.py
+  black --check {posargs} qiskit test tools examples setup.py
   -git fetch -q https://github.com/Qiskit/qiskit-terra.git :lint_incr_latest
   python {toxinidir}/tools/pylint_incr.py -rn -j4 -sn --paths :/qiskit/*.py :/test/*.py :/tools/*.py
   python {toxinidir}/tools/pylint_incr.py -rn -j4 -sn --disable='invalid-name,missing-module-docstring,redefined-outer-name' --paths :(glob,top)examples/python/*.py
@@ -59,7 +53,7 @@ commands =
 skip_install = true
 deps =
     -r requirements-dev.txt
-commands = black {posargs} qiskit test tools examples setup.py qiskit_pkg
+commands = black {posargs} qiskit test tools examples setup.py
 
 [testenv:coverage]
 basepython = python3