Merge branch 'main' into quantum-time-evo

.github/ISSUE_TEMPLATE/BUG_REPORT.yaml

@@ -0,0 +1,50 @@
+name: 🐛 Bug report
+description: Create a report to help us improve 🤔.
+labels: ["bug"]
+
+body:
+  - type: markdown
+    attributes:
+      value: Thank you for reporting!  Please also use the search to see if there are any other relevant issues or pull requests.
+
+  - type: textarea
+    attributes:
+      label: Environment
+      description: For the version of Terra, please give the actual version number (_e.g._ 0.18.3) if you are using a release version, or the first 7-8 characters of the commit hash if you have installed from `git`.  If anything else is relevant, you can add it to the list.
+      # The trailing spaces on the following lines are to make filling the form
+      # in easier.  The type is 'textarea' rather than three separate 'input's
+      # to make the resulting issue body less noisy with headings.
+      value: |
+        - **Qiskit Terra version**: 
+        - **Python version**: 
+        - **Operating system**: 
+    validations:
+      required: true
+
+  - type: textarea
+    attributes:
+      label: What is happening?
+      description: A short description of what is going wrong, in words.
+    validations:
+      required: true
+
+  - type: textarea
+    attributes:
+      label: How can we reproduce the issue?
+      description: Give some steps that show the bug.  A [minimal working example](https://stackoverflow.com/help/minimal-reproducible-example) of code with output is best.  If you are copying in code, please remember to enclose it in triple backticks (` ``` [multiline code goes here] ``` `) so that it [displays correctly](https://docs.github.com/en/github/writing-on-github/getting-started-with-writing-and-formatting-on-github/basic-writing-and-formatting-syntax).
+    validations:
+      required: true
+
+  - type: textarea
+    attributes:
+      label: What should happen?
+      description: A short description, including about the expected output of any code in the previous section.
+    validations:
+      required: true
+
+  - type: textarea
+    attributes:
+      label: Any suggestions?
+      description: Not required, but if you have suggestions for how a contributor should fix this, or any problems we should be aware of, let us know.
+    validations:
+      required: false

.github/ISSUE_TEMPLATE/ENHANCEMENT_REQUEST.yaml

@@ -0,0 +1,14 @@
+name: 💅 Enhancement request
+description: Suggest an improvement for this project 🆒!
+labels: ["type: enhancement"]
+
+body:
+  - type: markdown
+    attributes:
+      value: Please make sure to browse the opened and closed issues to make sure that this idea has not previously been discussed.
+
+  - type: textarea
+    attributes:
+      label: What is the expected enhancement?
+    validations:
+      required: true

.github/ISSUE_TEMPLATE/FEATURE_REQUEST.yaml

@@ -0,0 +1,14 @@
+name: 🚀 Feature request
+description: Suggest an idea for this project 💡!
+labels: ["type: feature request"]
+
+body:
+  - type: markdown
+    attributes:
+      value: Please make sure to browse the opened and closed issues to make sure that this idea has not previously been discussed.
+
+  - type: textarea
+    attributes:
+      label: What should we add?
+    validations:
+      required: true

.github/workflows/coverage.yml

@@ -3,6 +3,9 @@ on:
   push:
   pull_request:
     branches: ['main']
+concurrency:
+  group: ${{ github.repository }}-${{ github.ref }}-${{ github.head_ref }}-${{ github.workflow }}
+  cancel-in-progress: true
 jobs:
   coverage:
     name: Coverage

.mergify.yml

@@ -20,4 +20,4 @@ pull_request_rules:
     actions:
       backport:
         branches:
-          - stable/0.18
+          - stable/0.19

.pylintrc

@@ -33,7 +33,7 @@ unsafe-load-any-extension=no
 # A comma-separated list of package or module names from where C extensions may
 # be loaded. Extensions are loading into the active Python interpreter and may
 # run arbitrary code
-extension-pkg-whitelist=retworkx, numpy, tweedledum
+extension-pkg-allow-list=retworkx, numpy, tweedledum
 
 
 [MESSAGES CONTROL]

CONTRIBUTING.md

@@ -10,6 +10,28 @@ https://qiskit.org/documentation/contributing_to_qiskit.html
 In addition to the general guidelines there are specific details for
 contributing to terra, these are documented below.
 
+### Contents
+* [Choose an issue to work on](#Choose-an-issue-to-work-on)
+* [Pull request checklist](#pull-request-checklist)
+* [Changelog generation](#changelog-generation)
+* [Release Notes](#release-notes)
+* [Installing Qiskit Terra from source](#installing-qiskit-terra-from-source)
+* [Test](#test)
+  * [Snapshot testing for visualizations](#snapshot-testing-for-visualizations)
+* [Style and Lint](#style-and-lint)
+* [Development Cycle](#development-cycle)
+  * [Branches](#branches)
+  * [Release Cycle](#release-cycle)
+* [Adding deprecation warnings](#adding-deprecation-warnings)
+* [Dealing with git blame ignore list](#dealing-with-the-git-blame-ignore-list)
+
+### Choose an issue to work on
+Qiskit Terra uses the following labels to help non-maintainers find issues best suited to their interests and experience level:
+
+* [good first issue](https://github.com/Qiskit/qiskit-terra/issues?q=is%3Aopen+is%3Aissue+label%3A%22good+first+issue%22) - these issues are typically the simplest available to work on, perfect for newcomers. They should already be fully scoped, with a clear approach outlined in the descriptions.
+* [help wanted](https://github.com/Qiskit/qiskit-terra/issues?q=is%3Aopen+is%3Aissue+label%3A%22help+wanted%22) - these issues are generally more complex than good first issues. They typically cover work that core maintainers don't currently have capacity to implement and may require more investigation/discussion. These are a great option for experienced contributors looking for something a bit more challenging.
+* [short project](https://github.com/Qiskit/qiskit-terra/issues?q=is%3Aopen+is%3Aissue+label%3A%22short+project%22) - these issues are bigger pieces of work that require greater time commitment. Good options for hackathons, internship projects etc.
+
 ### Pull request checklist
 
 When submitting a pull request and you feel it is ready for review,

README.md

@@ -15,7 +15,7 @@ pip install qiskit
 
 PIP will handle all dependencies automatically and you will always install the latest (and well-tested) version.
 
-To install from source, follow the instructions in the [documentation](https://qiskit.org/documentation/contributing_to_qiskit.html#install-terra-from-source).
+To install from source, follow the instructions in the [documentation](https://qiskit.org/documentation/contributing_to_qiskit.html#install-install-from-source-label).
 
 ## Creating Your First Quantum Program in Qiskit Terra
 

azure-pipelines.yml

@@ -28,7 +28,7 @@ stages:
       variables:
         python.version: '3.7'
         CIBW_BEFORE_BUILD: pip install -U Cython
-        CIBW_SKIP: cp27-* cp34-* cp35-* pp*
+        CIBW_SKIP: cp27-* cp34-* cp35-* cp36-* pp*
         TWINE_USERNAME: qiskit
         CIBW_TEST_COMMAND: python {project}/examples/python/stochastic_swap.py
       steps:
@@ -72,7 +72,7 @@ stages:
       variables:
         python.version: '3.7'
         CIBW_BEFORE_BUILD: pip install -U Cython
-        CIBW_SKIP: cp27-* cp34-* cp35-* pp*
+        CIBW_SKIP: cp27-* cp34-* cp35-* cp36-* pp*
         TWINE_USERNAME: qiskit
         CIBW_TEST_COMMAND: python {project}/examples/python/stochastic_swap.py
       steps:
@@ -96,7 +96,7 @@ stages:
       variables:
         python.version: '3.7'
         CIBW_BEFORE_BUILD: pip install -U Cython
-        CIBW_SKIP: cp27-* cp34-* cp35-* pp*
+        CIBW_SKIP: cp27-* cp34-* cp35-* cp36-* pp*
         CIBW_ARCHS_MACOS: universal2
         TWINE_USERNAME: qiskit
         CIBW_TEST_COMMAND: python {project}/examples/python/stochastic_swap.py
@@ -120,12 +120,10 @@ stages:
       condition: startsWith(variables['Build.SourceBranch'], 'refs/tags')
       variables:
         CIBW_BEFORE_BUILD: pip install -U Cython
-        CIBW_SKIP: cp27-* cp34-* cp35-* pp*
+        CIBW_SKIP: cp27-* cp34-* cp35-* cp36-* pp*
         TWINE_USERNAME: qiskit
         CIBW_TEST_COMMAND: python {project}\examples\python\stochastic_swap.py
       steps:
-        - {task: UsePythonVersion@0, inputs: {versionSpec: '3.6', architecture: x86}}
-        - {task: UsePythonVersion@0, inputs: {versionSpec: '3.6', architecture: x64}}
         - {task: UsePythonVersion@0, inputs: {versionSpec: '3.7', architecture: x86}}
         - {task: UsePythonVersion@0, inputs: {versionSpec: '3.7', architecture: x64}}
         - {task: UsePythonVersion@0, inputs: {versionSpec: '3.8', architecture: x86}}
@@ -506,8 +504,6 @@ stages:
       pool: {vmImage: 'windows-latest'}
       strategy:
         matrix:
-          Python36:
-            python.version: '3.6'
           Python38:
             python.version: '3.8'
           Python39:
@@ -587,8 +583,6 @@ stages:
       pool: {vmImage: 'ubuntu-latest'}
       strategy:
         matrix:
-          Python36:
-            python.version: '3.6'
           Python38:
             python.version: '3.8'
           Python39:
@@ -671,8 +665,6 @@ stages:
       pool: {vmImage: 'macOS-10.15'}
       strategy:
         matrix:
-          Python36:
-            python.version: '3.6'
           Python38:
             python.version: '3.8'
           Python39:

docs/apidocs/synthesis.rst

@@ -0,0 +1,6 @@
+.. _qiskit-synthesis:
+
+.. automodule:: qiskit.synthesis
+   :no-members:
+   :no-inherited-members:
+   :no-special-members:

docs/apidocs/synthesis_aqc.rst

@@ -0,0 +1,6 @@
+.. _qiskit-transpiler-synthesis-aqc:
+
+.. automodule:: qiskit.transpiler.synthesis.aqc
+   :no-members:
+   :no-inherited-members:
+   :no-special-members:

docs/apidocs/terra.rst

@@ -21,6 +21,7 @@ Qiskit Terra API Reference
    providers_models
    pulse
    scheduler
+   synthesis
    qasm
    qobj
    qpy
@@ -32,6 +33,7 @@ Qiskit Terra API Reference
    transpiler_passes
    transpiler_preset
    transpiler_plugins
+   transpiler_builtin_plugins
    utils
    utils_mitigation
    opflow

docs/apidocs/transpiler_builtin_plugins.rst

@@ -0,0 +1,10 @@
+.. _qiskit-transpiler-builtin-plugins:
+
+=====================================
+Built-in Transpiler Synthesis Plugins
+=====================================
+
+.. toctree::
+   :maxdepth: 2
+
+   synthesis_aqc

docs/conf.py

@@ -23,7 +23,7 @@
 # The short X.Y version
 version = ""
 # The full version, including alpha/beta/rc tags
-release = "0.19.0"
+release = "0.20.0"
 
 extensions = [
     "sphinx.ext.napoleon",

qiskit/VERSION.txt

@@ -1 +1 @@
-0.19.0
+0.20.0

qiskit/__init__.py

@@ -17,7 +17,6 @@
 import pkgutil
 import sys
 import warnings
-import os
 
 # qiskit errors operator
 from qiskit.exceptions import QiskitError, MissingOptionalLibraryError
@@ -59,14 +58,6 @@
 __qiskit_version__ = QiskitVersion()
 
 
-if sys.version_info < (3, 7):
-    warnings.warn(
-        "Using Qiskit with Python 3.6 is deprecated as of qiskit-terra 0.17.0. "
-        "Support for running Qiskit with Python 3.6 will be removed in qiskit-terra 0.20.0.",
-        DeprecationWarning,
-    )
-
-
 class AerWrapper:
     """Lazy loading wrapper for Aer provider."""
 
@@ -127,3 +118,20 @@ def __getattr__(self, attr):
 
 Aer = AerWrapper()
 IBMQ = IBMQWrapper()
+
+__all__ = [
+    "Aer",
+    "AncillaRegister",
+    "BasicAer",
+    "ClassicalRegister",
+    "IBMQ",
+    "MissingOptionalLibraryError",
+    "QiskitError",
+    "QuantumCircuit",
+    "QuantumRegister",
+    "assemble",
+    "execute",
+    "schedule",
+    "sequence",
+    "transpile",
+]

qiskit/algorithms/amplitude_amplifiers/amplification_problem.py

@@ -54,9 +54,6 @@ def __init__(
                 if the ``oracle`` argument has an ``evaluate_bitstring`` method (currently only
                 provided by the :class:`~qiskit.circuit.library.PhaseOracle` class) this will be
                 used, otherwise this kwarg is required and **must** be specified.
-
-        Raises:
-            TypeError: if ``is_good_state`` is not provided and is required
         """
         self._oracle = oracle
         self._state_preparation = state_preparation
@@ -68,7 +65,7 @@ def __init__(
         elif hasattr(oracle, "evaluate_bitstring"):
             self._is_good_state = oracle.evaluate_bitstring
         else:
-            raise TypeError("A is_good_state function is required with the provided oracle")
+            self._is_good_state = None
 
     @property
     def oracle(self) -> Union[QuantumCircuit, Statevector]:
@@ -166,8 +163,8 @@ def is_good_state(self) -> Callable[[str], bool]:
             A callable that takes in a bitstring and returns True if the measurement is a good
             state, False otherwise.
         """
-        if callable(self._is_good_state):
-            return self._is_good_state
+        if (self._is_good_state is None) or callable(self._is_good_state):
+            return self._is_good_state  # returns None if no is_good_state arg has been set
         elif isinstance(self._is_good_state, list):
             if all(isinstance(good_bitstr, str) for good_bitstr in self._is_good_state):
                 return lambda bitstr: bitstr in self._is_good_state