Merge branch 'master' of https://github.com/PennyLaneAI/pennylane int…

…o capture_qml_cond

.github/workflows/scripts/set_nightly_version.py

@@ -0,0 +1,43 @@
+# Copyright 2024 Xanadu Quantum Technologies Inc.
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+#     http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+This module bumps the PennyLane development version by one unit.
+"""
+
+import os
+import re
+
+version_file_path = os.path.join(os.path.dirname(__file__), "../../../pennylane/_version.py")
+
+assert os.path.isfile(version_file_path)
+
+with open(version_file_path, "r+", encoding="UTF-8") as f:
+    lines = f.readlines()
+
+    version_line = lines[-1]
+    assert "__version__ = " in version_line
+
+    pattern = r"(\d+).(\d+).(\d+)-dev(\d+)"
+    match = re.search(pattern, version_line)
+    assert match
+
+    major, minor, bug, dev = match.groups()
+
+    replacement = f'__version__ = "{major}.{minor}.{bug}-dev{int(dev)+1}"\n'
+    lines[-1] = replacement
+
+    f.seek(0)
+    f.writelines(lines)
+    f.truncate()

.github/workflows/upload-nightly-release.yml

@@ -0,0 +1,48 @@
+name: Build nightly PennyLane releases for TestPyPI
+
+on:
+  schedule:
+    # Run every weekday at 5:50 EDT (cron is in UTC)
+    - cron: "50 9 * * 1-5"
+  workflow_dispatch:
+
+jobs:
+  setup:
+    name: Setup the release
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout PennyLane repo
+      uses: actions/checkout@v4
+      with:
+        ssh-key: ${{ secrets.NIGHTLY_VERSION_UPDATE_DEPLOY_KEY }}
+
+    - name: Bump dev version
+      run: |
+        python $GITHUB_WORKSPACE/.github/workflows/scripts/set_nightly_version.py
+
+    - name: Push new version
+      run: |
+        git config --global user.email '${{ secrets.AUTO_UPDATE_VERSION_RINGO_EMAIL }}'
+        git config --global user.name "ringo-but-quantum"
+        git add $GITHUB_WORKSPACE/pennylane/_version.py
+        git commit -m "[no ci] bump nightly version"
+        git push
+
+  upload:
+    name: Upload wheels to TestPyPI
+    needs: [setup]
+    runs-on: ubuntu-latest
+    permissions:
+      id-token: write  # IMPORTANT: mandatory for trusted publishing
+
+    steps:
+    - name: Build wheels
+      run: |
+        python -m pip install build
+        python -m build --wheel --outdir dist
+
+    - name: Upload wheels
+      uses: pypa/gh-action-pypi-publish@release/v1
+      with:
+        repository-url: https://test.pypi.org/legacy/
+        packages-dir: dist

doc/development/deprecations.rst

@@ -15,6 +15,12 @@ Pending deprecations
   - Deprecated in v0.38
   - Will be removed in v0.39
 
+* The logic for internally switching a device for a different backpropagation
+  compatible device is now deprecated, as it was in place for the deprecated `default.qubit.legacy`.
+
+  - Deprecated in v0.38
+  - Will be removed in v0.39  
+
 * The ``decomp_depth`` argument in ``qml.device`` is deprecated. 
 
   - Deprecated in v0.38

doc/releases/changelog-0.37.0.md

@@ -929,4 +929,4 @@ Kenya Sakka,
 Jay Soni,
 Kazuki Tsuoka,
 Haochen Paul Wang,
-David Wierichs.
+David Wierichs.

doc/releases/changelog-dev.md

@@ -7,19 +7,25 @@
 * The `qml.cond` function can be captured into plxpr. 
   [(#5999)](https://github.com/PennyLaneAI/pennylane/pull/5999)
 
+* A new method `process_density_matrix` has been added to the `ProbabilityMP` and `DensityMatrixMP`
+  classes, allowing for more efficient handling of quantum density matrices, particularly with batch
+  processing support. This method simplifies the calculation of probabilities from quantum states
+  represented as density matrices.
+  [(#5830)](https://github.com/PennyLaneAI/pennylane/pull/5830)
+
 * Resolved the bug in `qml.ThermalRelaxationError` where there was a typo from `tq` to `tg`.
   [(#5988)](https://github.com/PennyLaneAI/pennylane/issues/5988)
 
-* A new method `process_density_matrix` has been added to the `ProbabilityMP` and `DensityMatrixMP` classes, allowing for more efficient handling of quantum density matrices, particularly with batch processing support. This method simplifies the calculation of probabilities from quantum states represented as density matrices.
-  [(#5830)](https://github.com/PennyLaneAI/pennylane/pull/5830)
-
 * The `qml.PrepSelPrep` template is added. The template implements a block-encoding of a linear
   combination of unitaries.
   [(#5756)](https://github.com/PennyLaneAI/pennylane/pull/5756)
   [(#5987)](https://github.com/PennyLaneAI/pennylane/pull/5987)
 
-* The `split_to_single_terms` transform is added. This transform splits expectation values of sums
-  into multiple single-term measurements on a single tape, providing better support for simulators
+* A new function `qml.registers` has been added, enabling the creation of registers, which are implemented as a dictionary of `Wires` instances.
+  [(#5957)](https://github.com/PennyLaneAI/pennylane/pull/5957)
+
+* The `split_to_single_terms` transform is added. This transform splits expectation values of sums 
+  into multiple single-term measurements on a single tape, providing better support for simulators 
   that can handle non-commuting observables but don't natively support multi-term observables.
   [(#5884)](https://github.com/PennyLaneAI/pennylane/pull/5884)
 
@@ -36,6 +42,10 @@
 
 <h3>Improvements 🛠</h3>
 
+* `qml.devices.LegacyDeviceFacade` has been added to map the legacy devices to the new
+  device interface.
+  [(#5927)](https://github.com/PennyLaneAI/pennylane/pull/5927)
+
 * Added the `compute_sparse_matrix` method for `qml.ops.qubit.BasisStateProjector`.
   [(#5790)](https://github.com/PennyLaneAI/pennylane/pull/5790)
 
@@ -53,6 +63,12 @@
 * `QuantumScript.hash` is now cached, leading to performance improvements.
   [(#5919)](https://github.com/PennyLaneAI/pennylane/pull/5919)
 
+* Set operations are now supported by Wires.
+  [(#5983)](https://github.com/PennyLaneAI/pennylane/pull/5983)
+
+* `qml.dynamic_one_shot` now supports circuits using the `"tensorflow"` interface.
+  [(#5973)](https://github.com/PennyLaneAI/pennylane/pull/5973)
+
 * The representation for `Wires` has now changed to be more copy-paste friendly.
   [(#5958)](https://github.com/PennyLaneAI/pennylane/pull/5958)
 
@@ -111,6 +127,9 @@
   Hamiltonians.
   [(#5950)](https://github.com/PennyLaneAI/pennylane/pull/5950)
 
+* The `CNOT` operator no longer decomposes to itself. Instead, it raises a `qml.DecompositionUndefinedError`.
+  [(#6039)](https://github.com/PennyLaneAI/pennylane/pull/6039)
+
 <h4>Community contributions 🥳</h4>
 
 * `DefaultQutritMixed` readout error has been added using parameters `readout_relaxation_probs` and 
@@ -126,7 +145,7 @@
   the circuit.
   [(#5907)](https://github.com/PennyLaneAI/pennylane/pull/5907)
 
-* `queue_idx` attribute has been removed from the `Operator`, `CompositeOp`, and `SymboliOp` classes.
+* `queue_idx` attribute has been removed from the `Operator`, `CompositeOp`, and `SymbolicOp` classes.
   [(#6005)](https://github.com/PennyLaneAI/pennylane/pull/6005)
 
 * `qml.from_qasm` no longer removes measurements from the QASM code. Use 
@@ -187,6 +206,11 @@
   Instead, use `default.qubit` as it now supports backpropagation through the several backends.
   [(#5997)](https://github.com/PennyLaneAI/pennylane/pull/5997)
 
+* The logic for internally switching a device for a different backpropagation
+  compatible device is now deprecated, as it was in place for the deprecated
+  `default.qubit.legacy`.
+  [(#6032)](https://github.com/PennyLaneAI/pennylane/pull/6032)
+
 <h3>Documentation 📝</h3>
 
 * Improves the docstring for `QuantumScript.expand` and `qml.tape.tape.expand_tape`.
@@ -229,12 +253,12 @@ Ahmed Darwish,
 Lillian M. A. Frederiksen,
 Pietropaolo Frisoni,
 Emiliano Godinez,
+Austin Huang,
 Renke Huang,
 Josh Izaac,
 Soran Jahangiri,
 Korbinian Kottmann,
 Christina Lee,
-Austin Huang,
 William Maxwell,
 Vincent Michaud-Rioux,
 Anurav Modak,

pennylane/__init__.py

@@ -60,7 +60,7 @@
 from pennylane.configuration import Configuration
 from pennylane.drawer import draw, draw_mpl
 from pennylane.tracker import Tracker
-
+from pennylane.registers import registers
 from pennylane.io import *
 from pennylane.measurements import (
     counts,

pennylane/_version.py

@@ -16,4 +16,4 @@
 Version number (major.minor.patch[-label])
 """
 
-__version__ = "0.38.0-dev"
+__version__ = "0.38.0-dev3"

pennylane/debugging/snapshot.py

@@ -25,6 +25,8 @@
 
 def _is_snapshot_compatible(dev):
     # The `_debugger` attribute is a good enough proxy for snapshot compatibility
+    if isinstance(dev, qml.devices.LegacyDeviceFacade):
+        return _is_snapshot_compatible(dev.target_device)
     return hasattr(dev, "_debugger")
 
 

pennylane/devices/__init__.py

@@ -60,6 +60,7 @@
     DefaultTensor
     NullQubit
     DefaultQutritMixed
+    LegacyDeviceFacade
 
 Preprocessing Transforms
 ------------------------
@@ -152,6 +153,7 @@ def execute(self, circuits, execution_config = qml.devices.DefaultExecutionConfi
 from .device_constructor import device, refresh_devices
 from .device_api import Device
 from .default_qubit import DefaultQubit
+from .legacy_facade import LegacyDeviceFacade
 
 # DefaultQubitTF and DefaultQubitAutograd not imported here since this
 # would lead to an automatic import of tensorflow and autograd, which are

pennylane/devices/default_qubit.py

@@ -532,10 +532,7 @@ def preprocess(
 
         transform_program.add_transform(validate_device_wires, self.wires, name=self.name)
         transform_program.add_transform(
-            mid_circuit_measurements,
-            device=self,
-            mcm_config=config.mcm_config,
-            interface=config.interface,
+            mid_circuit_measurements, device=self, mcm_config=config.mcm_config
         )
         transform_program.add_transform(
             decompose,

pennylane/devices/execution_config.py

@@ -50,7 +50,7 @@ def __post_init__(self):
             None,
         ):
             raise ValueError(f"Invalid mid-circuit measurements method '{self.mcm_method}'.")
-        if self.postselect_mode not in ("hw-like", "fill-shots", None):
+        if self.postselect_mode not in ("hw-like", "fill-shots", "pad-invalid-samples", None):
             raise ValueError(f"Invalid postselection mode '{self.postselect_mode}'.")