From 472d739eb52964df17f0f73212a9169eb5202aa1 Mon Sep 17 00:00:00 2001
From: Mauko Quiroga <public@mauko.me>
Date: Wed, 16 Nov 2022 21:16:31 +0100
Subject: [PATCH 1/7] Remove constraint on packages

---
 openfisca_tasks/install.mk   |  6 +++---
 openfisca_tasks/lint.mk      | 12 ++++++------
 openfisca_tasks/publish.mk   |  6 +++---
 openfisca_tasks/test_code.mk | 10 +++++-----
 4 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/openfisca_tasks/install.mk b/openfisca_tasks/install.mk
index d4ffd8667a..6725577621 100644
--- a/openfisca_tasks/install.mk
+++ b/openfisca_tasks/install.mk
@@ -1,17 +1,17 @@
 ## Uninstall project's dependencies.
 uninstall:
 	@$(call print_help,$@:)
-	@pip freeze | grep -v "^-e" | sed "s/@.*//" | xargs pip uninstall -y
+	@python -m pip freeze | grep -v "^-e" | sed "s/@.*//" | xargs python -m pip uninstall -y
 
 ## Install project's overall dependencies
 install-deps:
 	@$(call print_help,$@:)
-	@pip install --upgrade pip twine wheel
+	@python -m pip install --upgrade pip twine wheel
 
 ## Install project's development dependencies.
 install-edit:
 	@$(call print_help,$@:)
-	@pip install --upgrade --editable ".[dev]"
+	@python -m pip install --upgrade --editable ".[dev]"
 
 ## Delete builds and compiled python files.
 clean:
diff --git a/openfisca_tasks/lint.mk b/openfisca_tasks/lint.mk
index 115c6267bb..5e1a6f3d73 100644
--- a/openfisca_tasks/lint.mk
+++ b/openfisca_tasks/lint.mk
@@ -11,7 +11,7 @@ check-syntax-errors: .
 ## Run linters to check for syntax and style errors.
 check-style: $(shell git ls-files "*.py")
 	@$(call print_help,$@:)
-	@flake8 $?
+	@python -m flake8 $?
 	@$(call print_pass,$@:)
 
 ## Run linters to check for syntax and style errors in the doc.
@@ -29,14 +29,14 @@ lint-doc-%:
 	@## able to integrate documentation improvements progresively.
 	@##
 	@$(call print_help,$(subst $*,%,$@:))
-	@flake8 --select=D101,D102,D103,DAR openfisca_core/$*
-	@pylint openfisca_core/$*
+	@python -m flake8 --select=D101,D102,D103,DAR openfisca_core/$*
+	@python -m pylint openfisca_core/$*
 	@$(call print_pass,$@:)
 
 ## Run static type checkers for type errors.
 check-types:
 	@$(call print_help,$@:)
-	@mypy --package openfisca_core --package openfisca_web_api
+	@python -m mypy --package openfisca_core --package openfisca_web_api
 	@$(call print_pass,$@:)
 
 ## Run static type checkers for type errors (strict).
@@ -48,7 +48,7 @@ lint-typing-strict: \
 ## Run static type checkers for type errors (strict).
 lint-typing-strict-%:
 	@$(call print_help,$(subst $*,%,$@:))
-	@mypy \
+	@python -m mypy \
 		--cache-dir .mypy_cache-openfisca_core.$* \
 		--implicit-reexport \
 		--strict \
@@ -58,5 +58,5 @@ lint-typing-strict-%:
 ## Run code formatters to correct style errors.
 format-style: $(shell git ls-files "*.py")
 	@$(call print_help,$@:)
-	@autopep8 $?
+	@python -m autopep8 $?
 	@$(call print_pass,$@:)
diff --git a/openfisca_tasks/publish.mk b/openfisca_tasks/publish.mk
index 9bac9ae365..981bffa86b 100644
--- a/openfisca_tasks/publish.mk
+++ b/openfisca_tasks/publish.mk
@@ -5,8 +5,8 @@ build:
 	@## This allows us to be sure tests are run against the packaged version
 	@## of openfisca-core, the same we put in the hands of users and reusers.
 	@$(call print_help,$@:)
-	@pip install --upgrade build
+	@python -m pip install --upgrade build
 	@python -m build
-	@pip uninstall --yes openfisca-core
-	@find dist -name "*.whl" -exec pip install {}[dev] \;
+	@python -m pip uninstall --yes openfisca-core
+	@find dist -name "*.whl" -exec python -m pip install {}[dev] \;
 	@$(call print_pass,$@:)
diff --git a/openfisca_tasks/test_code.mk b/openfisca_tasks/test_code.mk
index 63fdd4386a..7df7a905a5 100644
--- a/openfisca_tasks/test_code.mk
+++ b/openfisca_tasks/test_code.mk
@@ -10,8 +10,8 @@ install: install-deps install-edit install-test
 ## Enable regression testing with template repositories.
 install-test:
 	@$(call print_help,$@:)
-	@pip install --upgrade --no-dependencies openfisca-country-template
-	@pip install --upgrade --no-dependencies openfisca-extension-template
+	@python -m pip install --upgrade --no-deps openfisca-country-template
+	@python -m pip install --upgrade --no-deps openfisca-extension-template
 
 ## Run openfisca-core & country/extension template tests.
 test-code: test-core test-country test-extension
@@ -31,12 +31,12 @@ test-code: test-core test-country test-extension
 ## Run openfisca-core tests.
 test-core: $(shell pytest --quiet --quiet --collect-only 2> /dev/null | cut -f 1 -d ":")
 	@$(call print_help,$@:)
-	@pytest --quiet --capture=no --xdoctest --xdoctest-verbose=0 \
+	@python -m pytest --quiet --capture=no --xdoctest --xdoctest-verbose=0 \
 		openfisca_core/commons \
 		openfisca_core/holders \
 		openfisca_core/types
 	@PYTEST_ADDOPTS="$${PYTEST_ADDOPTS} ${pytest_args}" \
-		coverage run -m \
+		python -m coverage run -m \
 		${openfisca} test $? \
 		${openfisca_args}
 	@$(call print_pass,$@:)
@@ -63,4 +63,4 @@ test-extension:
 ## Print the coverage report.
 test-cov:
 	@$(call print_help,$@:)
-	@coverage report
+	@python -m coverage report

From f8939ca2c03a92ce443afc6ad5b3f05e893f230e Mon Sep 17 00:00:00 2001
From: Mauko Quiroga <public@mauko.me>
Date: Thu, 17 Nov 2022 19:47:03 +0100
Subject: [PATCH 2/7] Update doc & make

---
 openfisca_tasks/install.mk   | 12 +++++++++++-
 openfisca_tasks/lint.mk      | 12 ++++++------
 openfisca_tasks/publish.mk   |  6 +++---
 openfisca_tasks/test_code.mk |  5 +++--
 setup.py                     |  4 ++--
 5 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/openfisca_tasks/install.mk b/openfisca_tasks/install.mk
index 6725577621..d047a6eb15 100644
--- a/openfisca_tasks/install.mk
+++ b/openfisca_tasks/install.mk
@@ -1,7 +1,17 @@
 ## Uninstall project's dependencies.
 uninstall:
 	@$(call print_help,$@:)
-	@python -m pip freeze | grep -v "^-e" | sed "s/@.*//" | xargs python -m pip uninstall -y
+	@pip freeze | grep -v "^-e" | sed "s/@.*//" | xargs pip uninstall -y
+
+## Install project's overall dependencies
+install-deps:
+	@$(call print_help,$@:)
+	@pip install --upgrade pip twine wheel
+
+## Install project's development dependencies.
+install-edit:
+	@$(call print_help,$@:)
+	@pip install --upgrade --editable ".[dev]"
 
 ## Install project's overall dependencies
 install-deps:
diff --git a/openfisca_tasks/lint.mk b/openfisca_tasks/lint.mk
index 5e1a6f3d73..115c6267bb 100644
--- a/openfisca_tasks/lint.mk
+++ b/openfisca_tasks/lint.mk
@@ -11,7 +11,7 @@ check-syntax-errors: .
 ## Run linters to check for syntax and style errors.
 check-style: $(shell git ls-files "*.py")
 	@$(call print_help,$@:)
-	@python -m flake8 $?
+	@flake8 $?
 	@$(call print_pass,$@:)
 
 ## Run linters to check for syntax and style errors in the doc.
@@ -29,14 +29,14 @@ lint-doc-%:
 	@## able to integrate documentation improvements progresively.
 	@##
 	@$(call print_help,$(subst $*,%,$@:))
-	@python -m flake8 --select=D101,D102,D103,DAR openfisca_core/$*
-	@python -m pylint openfisca_core/$*
+	@flake8 --select=D101,D102,D103,DAR openfisca_core/$*
+	@pylint openfisca_core/$*
 	@$(call print_pass,$@:)
 
 ## Run static type checkers for type errors.
 check-types:
 	@$(call print_help,$@:)
-	@python -m mypy --package openfisca_core --package openfisca_web_api
+	@mypy --package openfisca_core --package openfisca_web_api
 	@$(call print_pass,$@:)
 
 ## Run static type checkers for type errors (strict).
@@ -48,7 +48,7 @@ lint-typing-strict: \
 ## Run static type checkers for type errors (strict).
 lint-typing-strict-%:
 	@$(call print_help,$(subst $*,%,$@:))
-	@python -m mypy \
+	@mypy \
 		--cache-dir .mypy_cache-openfisca_core.$* \
 		--implicit-reexport \
 		--strict \
@@ -58,5 +58,5 @@ lint-typing-strict-%:
 ## Run code formatters to correct style errors.
 format-style: $(shell git ls-files "*.py")
 	@$(call print_help,$@:)
-	@python -m autopep8 $?
+	@autopep8 $?
 	@$(call print_pass,$@:)
diff --git a/openfisca_tasks/publish.mk b/openfisca_tasks/publish.mk
index 981bffa86b..9bac9ae365 100644
--- a/openfisca_tasks/publish.mk
+++ b/openfisca_tasks/publish.mk
@@ -5,8 +5,8 @@ build:
 	@## This allows us to be sure tests are run against the packaged version
 	@## of openfisca-core, the same we put in the hands of users and reusers.
 	@$(call print_help,$@:)
-	@python -m pip install --upgrade build
+	@pip install --upgrade build
 	@python -m build
-	@python -m pip uninstall --yes openfisca-core
-	@find dist -name "*.whl" -exec python -m pip install {}[dev] \;
+	@pip uninstall --yes openfisca-core
+	@find dist -name "*.whl" -exec pip install {}[dev] \;
 	@$(call print_pass,$@:)
diff --git a/openfisca_tasks/test_code.mk b/openfisca_tasks/test_code.mk
index 7df7a905a5..703cf4ec20 100644
--- a/openfisca_tasks/test_code.mk
+++ b/openfisca_tasks/test_code.mk
@@ -4,6 +4,7 @@ openfisca = openfisca_core.scripts.openfisca_command
 ## The path to the installed packages.
 python_packages = $(shell python -c "import sysconfig; print(sysconfig.get_paths()[\"purelib\"])")
 
+<<<<<<< HEAD
 ## Run all tasks required for testing.
 install: install-deps install-edit install-test
 
@@ -36,7 +37,7 @@ test-core: $(shell pytest --quiet --quiet --collect-only 2> /dev/null | cut -f 1
 		openfisca_core/holders \
 		openfisca_core/types
 	@PYTEST_ADDOPTS="$${PYTEST_ADDOPTS} ${pytest_args}" \
-		python -m coverage run -m \
+		coverage run -m \
 		${openfisca} test $? \
 		${openfisca_args}
 	@$(call print_pass,$@:)
@@ -63,4 +64,4 @@ test-extension:
 ## Print the coverage report.
 test-cov:
 	@$(call print_help,$@:)
-	@python -m coverage report
+	@coverage report
diff --git a/setup.py b/setup.py
index 0eb2fa5624..504a5513ea 100644
--- a/setup.py
+++ b/setup.py
@@ -1,7 +1,7 @@
 """Package config file.
 
-This file contains all package's metadata, including the current version and
-its third-party dependencies.
+This file contains all the package's metadata, including the current version
+and its third-party dependencies.
 
 Note:
     For integration testing, OpenFisca-Core relies on two other packages,

From fc947b545cd39e12dfd418117ed17cbbf0ce1fc8 Mon Sep 17 00:00:00 2001
From: Mauko Quiroga <public@mauko.me>
Date: Mon, 21 Nov 2022 22:35:41 +0100
Subject: [PATCH 3/7] Add nox

---
 README.md  |  13 +++++++
 noxfile.py | 110 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 123 insertions(+)
 create mode 100644 noxfile.py

diff --git a/README.md b/README.md
index a3f18555f1..93597f7e1b 100644
--- a/README.md
+++ b/README.md
@@ -98,6 +98,19 @@ To run a single test:
 pytest tests/core/test_parameters.py -k test_parameter_for_period
 ```
 
+### Testing with Nox
+
+In order to test several Python and NumPy versions locally, we recommend you to
+install [pipx](https://pypa.github.io/pipx/installation/) and configure it with
+your a Python version manager like [pyenv](https://github.com/pyenv/pyenv) and  
+[nox](https://nox.thea.codes/en/stable/tutorial.html#installation).
+
+Then run:
+
+```sh
+nox -s
+```
+
 ## Types
 
 This repository relies on MyPy for optional dynamic & static type checking.
diff --git a/noxfile.py b/noxfile.py
new file mode 100644
index 0000000000..60625ff135
--- /dev/null
+++ b/noxfile.py
@@ -0,0 +1,110 @@
+"""Nox config file."""
+
+import nox
+
+nox.options.reuse_existing_virtualenvs = True
+nox.options.stop_on_first_error = True
+
+
+@nox.session(python = ("3.9", "3.8", "3.7"), tags = ("lint", "style"))
+@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+def style(session, numpy):
+    """Run tests."""
+
+    if session.python == "3.7" and numpy == "1.22":
+        return
+
+    session.install("--upgrade", "pip")
+    session.install(".[dev]")
+    session.install(f"numpy=={numpy}")
+    session.run("make", "check-style", external = True)
+
+
+@nox.session(python = ("3.9", "3.8", "3.7"), tags = ("lint", "docs"))
+@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+def docs(session, numpy):
+    """Run tests."""
+
+    if session.python == "3.7" and numpy == "1.22":
+        return
+
+    session.install("--upgrade", "pip")
+    session.install(".[dev]")
+    session.install(f"numpy=={numpy}")
+    session.run("make", "lint-doc", external = True)
+
+
+@nox.session(python = ("3.9", "3.8", "3.7"), tags = ("lint", "mypy"))
+@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+def mypy(session, numpy):
+    """Run tests."""
+
+    if session.python == "3.7" and numpy == "1.22":
+        return
+
+    session.install("--upgrade", "pip")
+    session.install(".[dev]")
+    session.install(f"numpy=={numpy}")
+    session.run("make", "check-types", external = True)
+
+
+@nox.session(python = ("3.9", "3.8", "3.7"), tags = ("lint", "mypy-hxc"))
+@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+def mypy_hxc(session, numpy):
+    """Run tests."""
+
+    if session.python == "3.7" and numpy == "1.22":
+        return
+
+    session.install("--upgrade", "pip")
+    session.install(".[dev]")
+    session.install(f"numpy=={numpy}")
+    session.run("make", "lint-typing-strict", external = True)
+
+
+@nox.session(python = ("3.9", "3.8", "3.7"), tags = ("test", "test-core"))
+@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+def test_core(session, numpy):
+    """Run tests."""
+
+    if session.python == "3.7" and numpy == "1.22":
+        return
+
+    session.install("--upgrade", "pip")
+    session.install(".[dev]")
+    session.install(f"numpy=={numpy}")
+    session.install("--no-deps", "openfisca-country-template")
+    session.install("--no-deps", "openfisca-extension-template")
+    session.run("make", "test-core", external = True)
+
+
+@nox.session(python = ("3.9", "3.8", "3.7"), tags = ("test", "test-country"))
+@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+def test_country(session, numpy):
+    """Run tests."""
+
+    if session.python == "3.7" and numpy == "1.22":
+        return
+
+    session.install("--upgrade", "pip")
+    session.install(".[dev]")
+    session.install(f"numpy=={numpy}")
+    session.install("--no-deps", "openfisca-country-template")
+    session.install("--no-deps", "openfisca-extension-template")
+    session.run("make", "test-country", external = True)
+
+
+@nox.session(python = ("3.9", "3.8", "3.7"), tags = ("test", "test-extension"))
+@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+def test_extension(session, numpy):
+    """Run tests."""
+
+    if session.python == "3.7" and numpy == "1.22":
+        return
+
+    session.install("--upgrade", "pip")
+    session.install(".[dev]")
+    session.install(f"numpy=={numpy}")
+    session.install("--no-deps", "openfisca-country-template")
+    session.install("--no-deps", "openfisca-extension-template")
+    session.run("make", "test-extension", external = True)

From 59adf63c595a7dbe744a4db74e0c48ac3063273c Mon Sep 17 00:00:00 2001
From: Mauko Quiroga <public@mauko.me>
Date: Tue, 22 Nov 2022 01:52:24 +0100
Subject: [PATCH 4/7] Fix deprecated numpy signature

---
 .gitignore                                | 2 ++
 openfisca_core/tracers/computation_log.py | 2 +-
 setup.py                                  | 2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/.gitignore b/.gitignore
index 00d9f19fb6..f89f5f76c2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,9 +3,11 @@
 *.pyc
 *~
 .coverage
+.mypy.ini
 .mypy_cache
 .mypy_cache*
 .noseids
+.nox
 .project
 .pydevproject
 .pytest_cache
diff --git a/openfisca_core/tracers/computation_log.py b/openfisca_core/tracers/computation_log.py
index 9bb830b8d2..8f1b297dfe 100644
--- a/openfisca_core/tracers/computation_log.py
+++ b/openfisca_core/tracers/computation_log.py
@@ -28,7 +28,7 @@ def display(
         if isinstance(value, EnumArray):
             value = value.decode_to_str()
 
-        return numpy.array2string(value, max_line_width = float("inf"))
+        return numpy.array2string(value, max_line_width = None)
 
     def lines(
             self,
diff --git a/setup.py b/setup.py
index 504a5513ea..1ff4a54c36 100644
--- a/setup.py
+++ b/setup.py
@@ -29,7 +29,7 @@
     'dpath >= 1.5.0, < 3.0.0',
     'nptyping == 1.4.4',
     'numexpr >= 2.7.0, <= 3.0',
-    'numpy >= 1.11, < 1.21',
+    'numpy >= 1.20.3, < 1.23.0',
     'psutil >= 5.4.7, < 6.0.0',
     'pytest >= 4.4.1, < 6.0.0',  # For openfisca test
     'PyYAML >= 3.10',

From 1720f67de6f9134fd4accf743044109c645c2c3e Mon Sep 17 00:00:00 2001
From: Mauko Quiroga <public@mauko.me>
Date: Tue, 22 Nov 2022 02:44:08 +0100
Subject: [PATCH 5/7] Remove nptyping

---
 openfisca_core/commons/formulas.py            | 33 ++++++------
 openfisca_core/tracers/computation_log.py     |  1 +
 openfisca_core/types/__init__.py              | 12 +----
 openfisca_core/types/_data.py                 | 51 -------------------
 .../types/{_domain.py => _types.py}           |  0
 setup.py                                      |  1 -
 6 files changed, 17 insertions(+), 81 deletions(-)
 delete mode 100644 openfisca_core/types/_data.py
 rename openfisca_core/types/{_domain.py => _types.py} (100%)

diff --git a/openfisca_core/commons/formulas.py b/openfisca_core/commons/formulas.py
index 4e13b925fb..188f6f2062 100644
--- a/openfisca_core/commons/formulas.py
+++ b/openfisca_core/commons/formulas.py
@@ -1,17 +1,13 @@
-from typing import Any, Dict, Sequence, TypeVar
+from typing import Any, Dict, Sequence
 
 import numpy
 
-from openfisca_core.types import ArrayLike, Array
-
-T = TypeVar("T")
-
 
 def apply_thresholds(
-        input: Array[float],
-        thresholds: ArrayLike[float],
-        choices: ArrayLike[float],
-        ) -> Array[float]:
+        input: numpy.float_,
+        thresholds: Sequence[float],
+        choices: Sequence[float],
+        ) -> numpy.ndarray:
     """Makes a choice based on an input and thresholds.
 
     From a list of ``choices``, this function selects one of these values
@@ -33,20 +29,21 @@ def apply_thresholds(
 
     Examples:
         >>> input = numpy.array([4, 5, 6, 7, 8])
-        >>> thresholds = [5, 7]
+        >>> thresholds =
+        [5, 7]
         >>> choices = [10, 15, 20]
         >>> apply_thresholds(input, thresholds, choices)
         array([10, 10, 15, 15, 20])
 
     """
 
-    condlist: Sequence[Array[bool]]
+    condlist: Sequence[numpy.bool_]
     condlist = [input <= threshold for threshold in thresholds]
 
     if len(condlist) == len(choices) - 1:
         # If a choice is provided for input > highest threshold, last condition
         # must be true to return it.
-        condlist += [True]
+        condlist += numpy.array([True])
 
     assert len(condlist) == len(choices), \
         " ".join([
@@ -57,7 +54,7 @@ def apply_thresholds(
     return numpy.select(condlist, choices)
 
 
-def concat(this: ArrayLike[str], that: ArrayLike[str]) -> Array[str]:
+def concat(this: Sequence[str], that: Sequence[str]) -> numpy.ndarray:
     """Concatenates the values of two arrays.
 
     Args:
@@ -90,9 +87,9 @@ def concat(this: ArrayLike[str], that: ArrayLike[str]) -> Array[str]:
 
 
 def switch(
-        conditions: Array[Any],
-        value_by_condition: Dict[float, T],
-        ) -> Array[T]:
+        conditions: numpy.ndarray,
+        value_by_condition: Dict[float, Any],
+        ) -> numpy.ndarray:
     """Mimicks a switch statement.
 
     Given an array of conditions, returns an array of the same size,
@@ -122,7 +119,7 @@ def switch(
 
     condlist = [
         conditions == condition
-        for condition in value_by_condition.keys()
+        for condition in tuple(value_by_condition.keys())
         ]
 
-    return numpy.select(condlist, value_by_condition.values())
+    return numpy.select(condlist, tuple(value_by_condition.values()))
diff --git a/openfisca_core/tracers/computation_log.py b/openfisca_core/tracers/computation_log.py
index 8f1b297dfe..4e3d20e074 100644
--- a/openfisca_core/tracers/computation_log.py
+++ b/openfisca_core/tracers/computation_log.py
@@ -27,6 +27,7 @@ def display(
             ) -> str:
         if isinstance(value, EnumArray):
             value = value.decode_to_str()
+            raise ValueError(type(value))
 
         return numpy.array2string(value, max_line_width = None)
 
diff --git a/openfisca_core/types/__init__.py b/openfisca_core/types/__init__.py
index 699133aecb..4e5833d980 100644
--- a/openfisca_core/types/__init__.py
+++ b/openfisca_core/types/__init__.py
@@ -5,9 +5,6 @@
 and expected behaviours.
 
 Official Public API:
-    * :attr:`.Array`
-    * ``ArrayLike``
-    * :attr:`.Cache`
     * :attr:`.Entity`
     * :attr:`.Formula`
     * :attr:`.Holder`
@@ -49,12 +46,7 @@
 
 # Official Public API
 
-from ._data import (  # noqa: F401
-    Array,
-    ArrayLike,
-    )
-
-from ._domain import (  # noqa: F401
+from ._types import (  # noqa: F401
     Entity,
     Formula,
     Holder,
@@ -70,8 +62,6 @@
     )
 
 __all__ = [
-    "Array",
-    "ArrayLike",
     "Entity",
     "Formula",
     "Holder",
diff --git a/openfisca_core/types/_data.py b/openfisca_core/types/_data.py
deleted file mode 100644
index ff7066d43a..0000000000
--- a/openfisca_core/types/_data.py
+++ /dev/null
@@ -1,51 +0,0 @@
-from typing import Sequence, TypeVar, Union
-
-from nptyping import types, NDArray as Array
-
-import numpy
-
-T = TypeVar("T", bool, bytes, float, int, object, str)
-
-types._ndarray_meta._Type = Union[type, numpy.dtype, TypeVar]
-
-ArrayLike = Union[Array[T], Sequence[T]]
-""":obj:`typing.Generic`: Type of any castable to :class:`numpy.ndarray`.
-
-These include any :obj:`numpy.ndarray` and sequences (like
-:obj:`list`, :obj:`tuple`, and so on).
-
-Examples:
-    >>> ArrayLike[float]
-    typing.Union[numpy.ndarray, typing.Sequence[float]]
-
-    >>> ArrayLike[str]
-    typing.Union[numpy.ndarray, typing.Sequence[str]]
-
-Note:
-    It is possible since numpy version 1.21 to specify the type of an
-    array, thanks to `numpy.typing.NDArray`_::
-
-        from numpy.typing import NDArray
-        NDArray[numpy.float64]
-
-    `mypy`_ provides `duck type compatibility`_, so an :obj:`int` is
-    considered to be valid whenever a :obj:`float` is expected.
-
-Todo:
-    * Refactor once numpy version >= 1.21 is used.
-
-.. versionadded:: 35.5.0
-
-.. versionchanged:: 35.6.0
-    Moved to :mod:`.types`
-
-.. _mypy:
-    https://mypy.readthedocs.io/en/stable/
-
-.. _duck type compatibility:
-    https://mypy.readthedocs.io/en/stable/duck_type_compatibility.html
-
-.. _numpy.typing.NDArray:
-    https://numpy.org/doc/stable/reference/typing.html#numpy.typing.NDArray
-
-"""
diff --git a/openfisca_core/types/_domain.py b/openfisca_core/types/_types.py
similarity index 100%
rename from openfisca_core/types/_domain.py
rename to openfisca_core/types/_types.py
diff --git a/setup.py b/setup.py
index 1ff4a54c36..f2612d44b8 100644
--- a/setup.py
+++ b/setup.py
@@ -27,7 +27,6 @@
 
 general_requirements = [
     'dpath >= 1.5.0, < 3.0.0',
-    'nptyping == 1.4.4',
     'numexpr >= 2.7.0, <= 3.0',
     'numpy >= 1.20.3, < 1.23.0',
     'psutil >= 5.4.7, < 6.0.0',

From 857d86a0f7dfa466ae7dc3307098e01ef9e9c6c9 Mon Sep 17 00:00:00 2001
From: Mauko Quiroga <public@mauko.me>
Date: Tue, 22 Nov 2022 13:17:26 +0100
Subject: [PATCH 6/7] Fix types in commons

---
 openfisca_core/commons/misc.py            |  4 +-
 openfisca_core/commons/rates.py           | 57 +++++++++++------------
 openfisca_core/tracers/computation_log.py |  1 -
 3 files changed, 29 insertions(+), 33 deletions(-)

diff --git a/openfisca_core/commons/misc.py b/openfisca_core/commons/misc.py
index c2edcb25dc..c0dd4ef342 100644
--- a/openfisca_core/commons/misc.py
+++ b/openfisca_core/commons/misc.py
@@ -1,6 +1,6 @@
 from typing import TypeVar
 
-from openfisca_core.types import Array
+import numpy
 
 T = TypeVar("T")
 
@@ -43,7 +43,7 @@ def empty_clone(original: T) -> T:
     return new
 
 
-def stringify_array(array: Array) -> str:
+def stringify_array(array: numpy.ndarray) -> str:
     """Generates a clean string representation of a numpy array.
 
     Args:
diff --git a/openfisca_core/commons/rates.py b/openfisca_core/commons/rates.py
index e9d67c322a..05a94b0396 100644
--- a/openfisca_core/commons/rates.py
+++ b/openfisca_core/commons/rates.py
@@ -1,15 +1,13 @@
-from typing import Optional
+from typing import Optional, Sequence
 
 import numpy
 
-from openfisca_core.types import ArrayLike, Array
-
 
 def average_rate(
-        target: Array[float],
-        varying: ArrayLike[float],
-        trim: Optional[ArrayLike[float]] = None,
-        ) -> Array[float]:
+        target: numpy.ndarray,
+        varying: Sequence[float],
+        trim: Optional[Sequence[float]] = None,
+        ) -> numpy.ndarray:
     """Computes the average rate of a target net income.
 
     Given a ``target`` net income, and according to the ``varying`` gross
@@ -41,32 +39,31 @@ def average_rate(
 
     """
 
-    average_rate: Array[float]
-
-    average_rate = 1 - target / varying
+    rate: numpy.ndarray
+    rate = 1 - target / varying
 
     if trim is not None:
 
-        average_rate = numpy.where(
-            average_rate <= max(trim),
-            average_rate,
+        rate = numpy.where(
+            rate <= max(trim),
+            rate,
             numpy.nan,
             )
 
-        average_rate = numpy.where(
-            average_rate >= min(trim),
-            average_rate,
+        rate = numpy.where(
+            rate >= min(trim),
+            rate,
             numpy.nan,
             )
 
-    return average_rate
+    return rate
 
 
 def marginal_rate(
-        target: Array[float],
-        varying: Array[float],
-        trim: Optional[ArrayLike[float]] = None,
-        ) -> Array[float]:
+        target: numpy.ndarray,
+        varying: numpy.ndarray,
+        trim: Optional[numpy.ndarray] = None,
+        ) -> numpy.ndarray:
     """Computes the marginal rate of a target net income.
 
     Given a ``target`` net income, and according to the ``varying`` gross
@@ -98,9 +95,9 @@ def marginal_rate(
 
     """
 
-    marginal_rate: Array[float]
+    rate: numpy.ndarray
 
-    marginal_rate = (
+    rate = (
         + 1
         - (target[:-1] - target[1:])
         / (varying[:-1] - varying[1:])
@@ -108,16 +105,16 @@ def marginal_rate(
 
     if trim is not None:
 
-        marginal_rate = numpy.where(
-            marginal_rate <= max(trim),
-            marginal_rate,
+        rate = numpy.where(
+            rate <= max(trim),
+            rate,
             numpy.nan,
             )
 
-        marginal_rate = numpy.where(
-            marginal_rate >= min(trim),
-            marginal_rate,
+        rate = numpy.where(
+            rate >= min(trim),
+            rate,
             numpy.nan,
             )
 
-    return marginal_rate
+    return rate
diff --git a/openfisca_core/tracers/computation_log.py b/openfisca_core/tracers/computation_log.py
index 4e3d20e074..8f1b297dfe 100644
--- a/openfisca_core/tracers/computation_log.py
+++ b/openfisca_core/tracers/computation_log.py
@@ -27,7 +27,6 @@ def display(
             ) -> str:
         if isinstance(value, EnumArray):
             value = value.decode_to_str()
-            raise ValueError(type(value))
 
         return numpy.array2string(value, max_line_width = None)
 

From 1d6e22a92fd2b9609472f1abfc6bea9f3751ce01 Mon Sep 17 00:00:00 2001
From: Mauko Quiroga <public@mauko.me>
Date: Tue, 22 Nov 2022 14:43:39 +0100
Subject: [PATCH 7/7] Fix computation log types

---
 noxfile.py                                    | 14 ++---
 openfisca_core/commons/__init__.py            |  5 +-
 openfisca_core/commons/formulas.py            | 11 ++--
 openfisca_core/commons/misc.py                | 35 +++++++++--
 openfisca_core/indexed_enums/enum_array.py    |  4 +-
 openfisca_core/populations/population.py      | 24 ++++----
 openfisca_core/tracers/computation_log.py     | 48 ++++++---------
 openfisca_core/tracers/flat_trace.py          | 44 +++++---------
 openfisca_core/tracers/full_tracer.py         | 59 ++++++++++---------
 openfisca_core/tracers/performance_log.py     | 31 +++++-----
 openfisca_core/tracers/trace_node.py          | 28 ++++-----
 openfisca_core/types/__init__.py              | 17 +++++-
 openfisca_core/types/_data.py                 |  3 +
 .../types/{_types.py => _domain.py}           | 32 ++++++++--
 openfisca_tasks/install.mk                    | 10 ----
 openfisca_tasks/lint.mk                       | 12 ++--
 openfisca_tasks/test_code.mk                  |  1 -
 setup.cfg                                     |  1 +
 setup.py                                      |  2 +-
 19 files changed, 202 insertions(+), 179 deletions(-)
 create mode 100644 openfisca_core/types/_data.py
 rename openfisca_core/types/{_types.py => _domain.py} (86%)

diff --git a/noxfile.py b/noxfile.py
index 60625ff135..7886e41569 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -7,7 +7,7 @@
 
 
 @nox.session(python = ("3.9", "3.8", "3.7"), tags = ("lint", "style"))
-@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+@nox.parametrize("numpy", ("1.23", "1.22", "1.21"))
 def style(session, numpy):
     """Run tests."""
 
@@ -21,7 +21,7 @@ def style(session, numpy):
 
 
 @nox.session(python = ("3.9", "3.8", "3.7"), tags = ("lint", "docs"))
-@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+@nox.parametrize("numpy", ("1.23", "1.22", "1.21"))
 def docs(session, numpy):
     """Run tests."""
 
@@ -35,7 +35,7 @@ def docs(session, numpy):
 
 
 @nox.session(python = ("3.9", "3.8", "3.7"), tags = ("lint", "mypy"))
-@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+@nox.parametrize("numpy", ("1.23", "1.22", "1.21"))
 def mypy(session, numpy):
     """Run tests."""
 
@@ -49,7 +49,7 @@ def mypy(session, numpy):
 
 
 @nox.session(python = ("3.9", "3.8", "3.7"), tags = ("lint", "mypy-hxc"))
-@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+@nox.parametrize("numpy", ("1.23", "1.22", "1.21"))
 def mypy_hxc(session, numpy):
     """Run tests."""
 
@@ -63,7 +63,7 @@ def mypy_hxc(session, numpy):
 
 
 @nox.session(python = ("3.9", "3.8", "3.7"), tags = ("test", "test-core"))
-@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+@nox.parametrize("numpy", ("1.23", "1.22", "1.21"))
 def test_core(session, numpy):
     """Run tests."""
 
@@ -79,7 +79,7 @@ def test_core(session, numpy):
 
 
 @nox.session(python = ("3.9", "3.8", "3.7"), tags = ("test", "test-country"))
-@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+@nox.parametrize("numpy", ("1.23", "1.22", "1.21"))
 def test_country(session, numpy):
     """Run tests."""
 
@@ -95,7 +95,7 @@ def test_country(session, numpy):
 
 
 @nox.session(python = ("3.9", "3.8", "3.7"), tags = ("test", "test-extension"))
-@nox.parametrize("numpy", ("1.22", "1.20", "1.21"))
+@nox.parametrize("numpy", ("1.23", "1.22", "1.21"))
 def test_extension(session, numpy):
     """Run tests."""
 
diff --git a/openfisca_core/commons/__init__.py b/openfisca_core/commons/__init__.py
index b3b5d8cbb2..7caa6c397a 100644
--- a/openfisca_core/commons/__init__.py
+++ b/openfisca_core/commons/__init__.py
@@ -8,6 +8,7 @@
     * :func:`.average_rate`
     * :func:`.concat`
     * :func:`.empty_clone`
+    * :func:`.flatten`
     * :func:`.marginal_rate`
     * :func:`.stringify_array`
     * :func:`.switch`
@@ -53,11 +54,11 @@
 # Official Public API
 
 from .formulas import apply_thresholds, concat, switch  # noqa: F401
-from .misc import empty_clone, stringify_array  # noqa: F401
+from .misc import empty_clone, flatten, stringify_array  # noqa: F401
 from .rates import average_rate, marginal_rate  # noqa: F401
 
 __all__ = ["apply_thresholds", "concat", "switch"]
-__all__ = ["empty_clone", "stringify_array", *__all__]
+__all__ = ["empty_clone", "flatten", "stringify_array", *__all__]
 __all__ = ["average_rate", "marginal_rate", *__all__]
 
 # Deprecated
diff --git a/openfisca_core/commons/formulas.py b/openfisca_core/commons/formulas.py
index 188f6f2062..d1da0fc880 100644
--- a/openfisca_core/commons/formulas.py
+++ b/openfisca_core/commons/formulas.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict, Sequence
+from typing import Any, Dict, Sequence, Union
 
 import numpy
 
@@ -29,21 +29,20 @@ def apply_thresholds(
 
     Examples:
         >>> input = numpy.array([4, 5, 6, 7, 8])
-        >>> thresholds =
-        [5, 7]
+        >>> thresholds = [5, 7]
         >>> choices = [10, 15, 20]
         >>> apply_thresholds(input, thresholds, choices)
         array([10, 10, 15, 15, 20])
 
     """
 
-    condlist: Sequence[numpy.bool_]
+    condlist: Sequence[Union[bool, numpy.bool_]]
     condlist = [input <= threshold for threshold in thresholds]
 
     if len(condlist) == len(choices) - 1:
         # If a choice is provided for input > highest threshold, last condition
         # must be true to return it.
-        condlist += numpy.array([True])
+        condlist += [True]
 
     assert len(condlist) == len(choices), \
         " ".join([
@@ -119,7 +118,7 @@ def switch(
 
     condlist = [
         conditions == condition
-        for condition in tuple(value_by_condition.keys())
+        for condition in value_by_condition.keys()
         ]
 
     return numpy.select(condlist, tuple(value_by_condition.values()))
diff --git a/openfisca_core/commons/misc.py b/openfisca_core/commons/misc.py
index c0dd4ef342..36619aa7e7 100644
--- a/openfisca_core/commons/misc.py
+++ b/openfisca_core/commons/misc.py
@@ -1,12 +1,14 @@
-from typing import TypeVar
+from typing import Any, Iterator, Optional, Sequence, TypeVar
 
-import numpy
+import itertools
+
+from openfisca_core import types
 
 T = TypeVar("T")
 
 
 def empty_clone(original: T) -> T:
-    """Creates an empty instance of the same class of the original object.
+    """Create an empty instance of the same class of the original object.
 
     Args:
         original: An object to clone.
@@ -43,8 +45,31 @@ def empty_clone(original: T) -> T:
     return new
 
 
-def stringify_array(array: numpy.ndarray) -> str:
-    """Generates a clean string representation of a numpy array.
+def flatten(seqs: Sequence[Sequence[T]]) -> Iterator[T]:
+    """Flatten a sequence of sequences.
+
+    Args:
+        seqs: Any sequence of sequences.
+
+    Returns:
+        An iterator with the values.
+
+    Examples:
+        >>> list(flatten([(1, 2), (3, 4)]))
+        [1, 2, 3, 4]
+
+        >>> list(flatten(["ab", "cd"]))
+        ['a', 'b', 'c', 'd']
+
+    .. versionadded:: 36.0.0
+
+    """
+
+    return itertools.chain.from_iterable(seqs)
+
+
+def stringify_array(array: Optional[types.Array[Any]]) -> str:
+    """Generate a clean string representation of a numpy array.
 
     Args:
         array: An array.
diff --git a/openfisca_core/indexed_enums/enum_array.py b/openfisca_core/indexed_enums/enum_array.py
index 6a77be57a7..3ffa79b87c 100644
--- a/openfisca_core/indexed_enums/enum_array.py
+++ b/openfisca_core/indexed_enums/enum_array.py
@@ -63,7 +63,7 @@ def _forbidden_operation(self, other: Any) -> NoReturn:
     __and__ = _forbidden_operation
     __or__ = _forbidden_operation
 
-    def decode(self) -> numpy.object_:
+    def decode(self) -> numpy.ndarray:
         """
         Return the array of enum items corresponding to self.
 
@@ -82,7 +82,7 @@ def decode(self) -> numpy.object_:
             list(self.possible_values),
             )
 
-    def decode_to_str(self) -> numpy.str_:
+    def decode_to_str(self) -> numpy.ndarray:
         """
         Return the array of string identifiers corresponding to self.
 
diff --git a/openfisca_core/populations/population.py b/openfisca_core/populations/population.py
index cb243aff70..3ec95a4a2f 100644
--- a/openfisca_core/populations/population.py
+++ b/openfisca_core/populations/population.py
@@ -10,7 +10,7 @@
 from openfisca_core import periods, projectors
 from openfisca_core.holders import Holder, MemoryUsage
 from openfisca_core.projectors import Projector
-from openfisca_core.types import Array, Entity, Period, Role, Simulation
+from openfisca_core.types import Entity, Period, Role, Simulation
 
 from . import config
 
@@ -21,14 +21,14 @@ class Population:
     entity: Entity
     _holders: Dict[str, Holder]
     count: int
-    ids: Array[str]
+    ids: numpy.ndarray
 
     def __init__(self, entity: Entity) -> None:
         self.simulation = None
         self.entity = entity
         self._holders = {}
         self.count = 0
-        self.ids = []
+        self.ids = numpy.array([])
 
     def clone(self, simulation: Simulation) -> Population:
         result = Population(self.entity)
@@ -38,14 +38,14 @@ def clone(self, simulation: Simulation) -> Population:
         result.ids = self.ids
         return result
 
-    def empty_array(self) -> Array[float]:
+    def empty_array(self) -> numpy.ndarray:
         return numpy.zeros(self.count)
 
     def filled_array(
             self,
             value: Union[float, bool],
             dtype: Optional[numpy.dtype] = None,
-            ) -> Union[Array[float], Array[bool]]:
+            ) -> numpy.ndarray:
         return numpy.full(self.count, value, dtype)
 
     def __getattr__(self, attribute: str) -> Projector:
@@ -64,7 +64,7 @@ def get_index(self, id: str) -> int:
 
     def check_array_compatible_with_entity(
             self,
-            array: Array[float],
+            array: numpy.ndarray,
             ) -> None:
         if self.count == array.size:
             return None
@@ -95,7 +95,7 @@ def __call__(
             variable_name: str,
             period: Optional[Union[int, str, Period]] = None,
             options: Optional[Sequence[str]] = None,
-            ) -> Optional[Array[float]]:
+            ) -> Optional[Sequence[float]]:
         """
             Calculate the variable ``variable_name`` for the entity and the period ``period``, using the variable formula if it exists.
 
@@ -169,7 +169,7 @@ def get_memory_usage(
             })
 
     @projectors.projectable
-    def has_role(self, role: Role) -> Optional[Array[bool]]:
+    def has_role(self, role: Role) -> Optional[Sequence[bool]]:
         """
             Check if a person has a given role within its `GroupEntity`
 
@@ -195,10 +195,10 @@ def has_role(self, role: Role) -> Optional[Array[bool]]:
     @projectors.projectable
     def value_from_partner(
             self,
-            array: Array[float],
+            array: numpy.ndarray,
             entity: Projector,
             role: Role,
-            ) -> Optional[Array[float]]:
+            ) -> Optional[numpy.ndarray]:
         self.check_array_compatible_with_entity(array)
         self.entity.check_role_validity(role)
 
@@ -218,9 +218,9 @@ def value_from_partner(
     def get_rank(
             self,
             entity: Population,
-            criteria: Array[float],
+            criteria: Sequence[float],
             condition: bool = True,
-            ) -> Array[int]:
+            ) -> numpy.ndarray:
         """
         Get the rank of a person within an entity according to a criteria.
         The person with rank 0 has the minimum value of criteria.
diff --git a/openfisca_core/tracers/computation_log.py b/openfisca_core/tracers/computation_log.py
index 8f1b297dfe..285c094f38 100644
--- a/openfisca_core/tracers/computation_log.py
+++ b/openfisca_core/tracers/computation_log.py
@@ -1,40 +1,31 @@
 from __future__ import annotations
 
-import typing
-from typing import List, Optional, Union
+from typing import Any, Optional, Sequence
 
-import numpy
-
-from .. import tracers
-from openfisca_core.indexed_enums import EnumArray
+import sys
 
-if typing.TYPE_CHECKING:
-    from numpy.typing import ArrayLike
+import numpy
 
-    Array = Union[EnumArray, ArrayLike]
+from openfisca_core import commons, types
 
 
 class ComputationLog:
+    _full_tracer: types.FullTracer
 
-    _full_tracer: tracers.FullTracer
-
-    def __init__(self, full_tracer: tracers.FullTracer) -> None:
+    def __init__(self, full_tracer: types.FullTracer) -> None:
         self._full_tracer = full_tracer
 
-    def display(
-            self,
-            value: Optional[Array],
-            ) -> str:
-        if isinstance(value, EnumArray):
+    def display(self, value: types.Array[Any]) -> str:
+        if isinstance(value, types.EnumArray):
             value = value.decode_to_str()
 
-        return numpy.array2string(value, max_line_width = None)
+        return numpy.array2string(value, max_line_width = sys.maxsize)
 
     def lines(
             self,
             aggregate: bool = False,
             max_depth: Optional[int] = None,
-            ) -> List[str]:
+            ) -> Sequence[str]:
         depth = 1
 
         lines_by_tree = [
@@ -43,7 +34,7 @@ def lines(
             in self._full_tracer.trees
             ]
 
-        return self._flatten(lines_by_tree)
+        return tuple(commons.flatten(lines_by_tree))
 
     def print_log(self, aggregate = False, max_depth = None) -> None:
         """
@@ -67,11 +58,14 @@ def print_log(self, aggregate = False, max_depth = None) -> None:
 
     def _get_node_log(
             self,
-            node: tracers.TraceNode,
+            node: types.TraceNode,
             depth: int,
             aggregate: bool,
             max_depth: Optional[int],
-            ) -> List[str]:
+            ) -> Sequence[str]:
+
+        node_log: Sequence[str]
+        children_log: Sequence[Sequence[str]]
 
         if max_depth is not None and depth > max_depth:
             return []
@@ -84,12 +78,12 @@ def _get_node_log(
             in node.children
             ]
 
-        return node_log + self._flatten(children_logs)
+        return [*node_log, *commons.flatten(children_logs)]
 
     def _print_line(
             self,
             depth: int,
-            node: tracers.TraceNode,
+            node: types.TraceNode,
             aggregate: bool,
             max_depth: Optional[int],
             ) -> str:
@@ -114,9 +108,3 @@ def _print_line(
             formatted_value = self.display(value)
 
         return f"{indent}{node.name}<{node.period}> >> {formatted_value}"
-
-    def _flatten(
-            self,
-            lists: List[List[str]],
-            ) -> List[str]:
-        return [item for list_ in lists for item in list_]
diff --git a/openfisca_core/tracers/flat_trace.py b/openfisca_core/tracers/flat_trace.py
index d51dd2576b..4d03f4eab1 100644
--- a/openfisca_core/tracers/flat_trace.py
+++ b/openfisca_core/tracers/flat_trace.py
@@ -1,28 +1,19 @@
 from __future__ import annotations
 
-import typing
-from typing import Dict, Optional, Union
+from typing import Any, Dict
 
 import numpy
 
-from openfisca_core import tracers
-from openfisca_core.indexed_enums import EnumArray
-
-if typing.TYPE_CHECKING:
-    from numpy.typing import ArrayLike
-
-    Array = Union[EnumArray, ArrayLike]
-    Trace = Dict[str, dict]
+from openfisca_core import indexed_enums as enums, types
 
 
 class FlatTrace:
+    _full_tracer: types.FullTracer
 
-    _full_tracer: tracers.FullTracer
-
-    def __init__(self, full_tracer: tracers.FullTracer) -> None:
+    def __init__(self, full_tracer: types.FullTracer) -> None:
         self._full_tracer = full_tracer
 
-    def key(self, node: tracers.TraceNode) -> str:
+    def key(self, node: types.TraceNode) -> str:
         name = node.name
         period = node.period
         return f"{name}<{period}>"
@@ -52,26 +43,19 @@ def get_serialized_trace(self) -> dict:
             for key, flat_trace in self.get_trace().items()
             }
 
-    def serialize(
-            self,
-            value: Optional[Array],
-            ) -> Union[Optional[Array], list]:
-        if isinstance(value, EnumArray):
-            value = value.decode_to_str()
+    def serialize(self, value: Any) -> Any:
+        if not isinstance(value, numpy.ndarray):
+            return value
 
-        if isinstance(value, numpy.ndarray) and \
-           numpy.issubdtype(value.dtype, numpy.dtype(bytes)):
-            value = value.astype(numpy.dtype(str))
+        if isinstance(value, enums.EnumArray):
+            return value.decode_to_str().tolist()
 
-        if isinstance(value, numpy.ndarray):
-            value = value.tolist()
+        if numpy.issubdtype(value.dtype, numpy.dtype(bytes)):
+            return value.astype(numpy.dtype(str)).tolist()
 
-        return value
+        return value.tolist()
 
-    def _get_flat_trace(
-            self,
-            node: tracers.TraceNode,
-            ) -> Trace:
+    def _get_flat_trace(self, node: types.TraceNode) -> Dict[str, dict]:
         key = self.key(node)
 
         node_trace = {
diff --git a/openfisca_core/tracers/full_tracer.py b/openfisca_core/tracers/full_tracer.py
index 6638a789d4..29c90547c6 100644
--- a/openfisca_core/tracers/full_tracer.py
+++ b/openfisca_core/tracers/full_tracer.py
@@ -1,34 +1,34 @@
 from __future__ import annotations
 
 import time
-import typing
-from typing import Dict, Iterator, List, Optional, Union
+from typing import Any, Dict, Iterator, List, Optional, Sequence, Union
 
-from .. import tracers
+from openfisca_core import types
 
-if typing.TYPE_CHECKING:
-    from numpy.typing import ArrayLike
+from .computation_log import ComputationLog
+from .flat_trace import FlatTrace
+from .performance_log import PerformanceLog
+from .simple_tracer import SimpleTracer
+from .trace_node import TraceNode
 
-    from openfisca_core.periods import Period
-
-    Stack = List[Dict[str, Union[str, Period]]]
+Stack = List[Dict[str, Union[str, types.Period]]]
+Value = Union[types.Array[Any], Sequence[Any]]
 
 
 class FullTracer:
-
-    _simple_tracer: tracers.SimpleTracer
+    _simple_tracer: SimpleTracer
     _trees: list
-    _current_node: Optional[tracers.TraceNode]
+    _current_node: Optional[types.TraceNode]
 
     def __init__(self) -> None:
-        self._simple_tracer = tracers.SimpleTracer()
+        self._simple_tracer = SimpleTracer()
         self._trees = []
         self._current_node = None
 
     def record_calculation_start(
             self,
             variable: str,
-            period: Period,
+            period: types.Period,
             ) -> None:
         self._simple_tracer.record_calculation_start(variable, period)
         self._enter_calculation(variable, period)
@@ -37,9 +37,9 @@ def record_calculation_start(
     def _enter_calculation(
             self,
             variable: str,
-            period: Period,
+            period: types.Period,
             ) -> None:
-        new_node = tracers.TraceNode(
+        new_node = TraceNode(
             name = variable,
             period = period,
             parent = self._current_node,
@@ -56,13 +56,14 @@ def _enter_calculation(
     def record_parameter_access(
             self,
             parameter: str,
-            period: Period,
-            value: ArrayLike,
+            period: types.Period,
+            value: Value,
             ) -> None:
 
         if self._current_node is not None:
-            self._current_node.parameters.append(
-                tracers.TraceNode(name = parameter, period = period, value = value),
+            self._current_node.parameters = (
+                *self._current_node.parameters,
+                TraceNode(parameter, period, value = value),
                 )
 
     def _record_start_time(
@@ -75,7 +76,7 @@ def _record_start_time(
         if self._current_node is not None:
             self._current_node.start = time_in_s
 
-    def record_calculation_result(self, value: ArrayLike) -> None:
+    def record_calculation_result(self, value: Value) -> None:
         if self._current_node is not None:
             self._current_node.value = value
 
@@ -103,20 +104,20 @@ def stack(self) -> Stack:
         return self._simple_tracer.stack
 
     @property
-    def trees(self) -> List[tracers.TraceNode]:
+    def trees(self) -> List[TraceNode]:
         return self._trees
 
     @property
-    def computation_log(self) -> tracers.ComputationLog:
-        return tracers.ComputationLog(self)
+    def computation_log(self) -> ComputationLog:
+        return ComputationLog(self)
 
     @property
-    def performance_log(self) -> tracers.PerformanceLog:
-        return tracers.PerformanceLog(self)
+    def performance_log(self) -> PerformanceLog:
+        return PerformanceLog(self)
 
     @property
-    def flat_trace(self) -> tracers.FlatTrace:
-        return tracers.FlatTrace(self)
+    def flat_trace(self) -> FlatTrace:
+        return FlatTrace(self)
 
     def _get_time_in_sec(self) -> float:
         return time.time_ns() / (10**9)
@@ -130,7 +131,7 @@ def generate_performance_graph(self, dir_path: str) -> None:
     def generate_performance_tables(self, dir_path: str) -> None:
         self.performance_log.generate_performance_tables(dir_path)
 
-    def _get_nb_requests(self, tree: tracers.TraceNode, variable: str) -> int:
+    def _get_nb_requests(self, tree: TraceNode, variable: str) -> int:
         tree_call = tree.name == variable
         children_calls = sum(
             self._get_nb_requests(child, variable)
@@ -153,7 +154,7 @@ def get_flat_trace(self) -> dict:
     def get_serialized_flat_trace(self) -> dict:
         return self.flat_trace.get_serialized_trace()
 
-    def browse_trace(self) -> Iterator[tracers.TraceNode]:
+    def browse_trace(self) -> Iterator[TraceNode]:
 
         def _browse_node(node):
             yield node
diff --git a/openfisca_core/tracers/performance_log.py b/openfisca_core/tracers/performance_log.py
index 754d7f8056..f9a9066c47 100644
--- a/openfisca_core/tracers/performance_log.py
+++ b/openfisca_core/tracers/performance_log.py
@@ -1,23 +1,24 @@
 from __future__ import annotations
 
+from typing import Dict, Tuple, Sequence
+
 import csv
 import importlib.resources
 import itertools
 import json
 import os
-import typing
 
-from .. import tracers
+from openfisca_core import types
 
-if typing.TYPE_CHECKING:
-    Trace = typing.Dict[str, dict]
-    Calculation = typing.Tuple[str, dict]
-    SortedTrace = typing.List[Calculation]
+from .trace_node import TraceNode
 
+Trace = Dict[str, dict]
+Calculation = Tuple[str, dict]
+SortedTrace = Sequence[Calculation]
 
-class PerformanceLog:
 
-    def __init__(self, full_tracer: tracers.FullTracer) -> None:
+class PerformanceLog:
+    def __init__(self, full_tracer: types.FullTracer) -> None:
         self._full_tracer = full_tracer
 
     def generate_graph(self, dir_path: str) -> None:
@@ -66,7 +67,7 @@ def generate_performance_tables(self, dir_path: str) -> None:
     def aggregate_calculation_times(
             self,
             flat_trace: Trace,
-            ) -> typing.Dict[str, dict]:
+            ) -> Dict[str, dict]:
 
         def _aggregate_calculations(calculations: list) -> dict:
             calculation_count = len(calculations)
@@ -85,10 +86,10 @@ def _aggregate_calculations(calculations: list) -> dict:
 
             return {
                 'calculation_count': calculation_count,
-                'calculation_time': tracers.TraceNode.round(calculation_time),
-                'formula_time': tracers.TraceNode.round(formula_time),
-                'avg_calculation_time': tracers.TraceNode.round(calculation_time / calculation_count),
-                'avg_formula_time': tracers.TraceNode.round(formula_time / calculation_count),
+                'calculation_time': TraceNode.round(calculation_time),
+                'formula_time': TraceNode.round(formula_time),
+                'avg_calculation_time': TraceNode.round(calculation_time / calculation_count),
+                'avg_formula_time': TraceNode.round(formula_time / calculation_count),
                 }
 
         def _groupby(calculation: Calculation) -> str:
@@ -112,7 +113,7 @@ def _json(self) -> dict:
             'children': children,
             }
 
-    def _json_tree(self, tree: tracers.TraceNode) -> dict:
+    def _json_tree(self, tree: types.TraceNode) -> dict:
         calculation_total_time = tree.calculation_time()
         children = [self._json_tree(child) for child in tree.children]
 
@@ -122,7 +123,7 @@ def _json_tree(self, tree: tracers.TraceNode) -> dict:
             'children': children,
             }
 
-    def _write_csv(self, path: str, rows: typing.List[dict]) -> None:
+    def _write_csv(self, path: str, rows: Sequence[dict]) -> None:
         fieldnames = list(rows[0].keys())
 
         with open(path, 'w') as csv_file:
diff --git a/openfisca_core/tracers/trace_node.py b/openfisca_core/tracers/trace_node.py
index 93b630886c..9190198645 100644
--- a/openfisca_core/tracers/trace_node.py
+++ b/openfisca_core/tracers/trace_node.py
@@ -1,30 +1,24 @@
 from __future__ import annotations
 
-import dataclasses
-import typing
-
-if typing.TYPE_CHECKING:
-    import numpy
+from typing import Any, Optional, Sequence, Union
 
-    from openfisca_core.indexed_enums import EnumArray
-    from openfisca_core.periods import Period
+import dataclasses
 
-    Array = typing.Union[EnumArray, numpy.typing.ArrayLike]
-    Time = typing.Union[float, int]
+from openfisca_core import types
 
 
 @dataclasses.dataclass
 class TraceNode:
     name: str
-    period: Period
-    parent: typing.Optional[TraceNode] = None
-    children: typing.List[TraceNode] = dataclasses.field(default_factory = list)
-    parameters: typing.List[TraceNode] = dataclasses.field(default_factory = list)
-    value: typing.Optional[Array] = None
+    period: types.Period
+    parent: Optional[TraceNode] = None
+    children: Sequence[TraceNode] = dataclasses.field(default_factory = list)
+    parameters: Sequence[TraceNode] = dataclasses.field(default_factory = list)
+    value: Optional[Union[types.Array[Any], Sequence[Any]]] = None
     start: float = 0
     end: float = 0
 
-    def calculation_time(self, round_: bool = True) -> Time:
+    def calculation_time(self, round_: bool = True) -> float:
         result = self.end - self.start
 
         if round_:
@@ -47,8 +41,8 @@ def formula_time(self) -> float:
         return self.round(result)
 
     def append_child(self, node: TraceNode) -> None:
-        self.children.append(node)
+        self.children = (*self.children, node)
 
     @staticmethod
-    def round(time: Time) -> float:
+    def round(time: float) -> float:
         return float(f'{time:.4g}')  # Keep only 4 significant figures
diff --git a/openfisca_core/types/__init__.py b/openfisca_core/types/__init__.py
index 4e5833d980..31c7e340b1 100644
--- a/openfisca_core/types/__init__.py
+++ b/openfisca_core/types/__init__.py
@@ -5,8 +5,11 @@
 and expected behaviours.
 
 Official Public API:
+    * :attr:`.Array`
     * :attr:`.Entity`
+    * :attr:`.EnumArray`
     * :attr:`.Formula`
+    * :attr:`.FullTracer`
     * :attr:`.Holder`
     * :attr:`.Instant`
     * :attr:`.ParameterNodeAtInstant`
@@ -16,6 +19,7 @@
     * :attr:`.Role`,
     * :attr:`.Simulation`,
     * :attr:`.TaxBenefitSystem`
+    * :attr:`.TraceNode`
     * :attr:`.Variable`
 
 Note:
@@ -46,9 +50,15 @@
 
 # Official Public API
 
-from ._types import (  # noqa: F401
+from ._data import (  # noqa: F401
+    Array,
+    )
+
+from ._domain import (  # noqa: F401
     Entity,
+    EnumArray,
     Formula,
+    FullTracer,
     Holder,
     Instant,
     ParameterNodeAtInstant,
@@ -58,12 +68,16 @@
     Role,
     Simulation,
     TaxBenefitSystem,
+    TraceNode,
     Variable,
     )
 
 __all__ = [
+    "Array",
     "Entity",
+    "EnumArray",
     "Formula",
+    "FullTracer",
     "Holder",
     "Instant",
     "ParameterNodeAtInstant",
@@ -73,5 +87,6 @@
     "Role",
     "Simulation",
     "TaxBenefitSystem",
+    "TraceNode",
     "Variable",
     ]
diff --git a/openfisca_core/types/_data.py b/openfisca_core/types/_data.py
new file mode 100644
index 0000000000..572809207f
--- /dev/null
+++ b/openfisca_core/types/_data.py
@@ -0,0 +1,3 @@
+from __future__ import annotations
+
+from numpy.typing import NDArray as Array  # noqa: F401
diff --git a/openfisca_core/types/_types.py b/openfisca_core/types/_domain.py
similarity index 86%
rename from openfisca_core/types/_types.py
rename to openfisca_core/types/_domain.py
index 643f27964f..0b61676635 100644
--- a/openfisca_core/types/_types.py
+++ b/openfisca_core/types/_domain.py
@@ -10,7 +10,6 @@
 
 class Entity(Protocol):
     """Entity protocol."""
-
     key: Any
     plural: Any
 
@@ -30,6 +29,15 @@ def get_variable(
         """Abstract method."""
 
 
+@typing_extensions.runtime_checkable
+class EnumArray(Protocol):
+    """EnumArray protocol."""
+
+    @abc.abstractmethod
+    def decode_to_str(self) -> numpy.ndarray:
+        """Abstract method."""
+
+
 class Formula(Protocol):
     """Formula protocol."""
 
@@ -43,6 +51,12 @@ def __call__(
         """Abstract method."""
 
 
+class FullTracer(Protocol):
+    """FullTracer protocol."""
+    trees: Any
+    browse_trace: Any
+
+
 class Holder(Protocol):
     """Holder protocol."""
 
@@ -80,6 +94,7 @@ class Period(Protocol):
     @abc.abstractmethod
     def start(self) -> Any:
         """Abstract method."""
+
     @property
     @abc.abstractmethod
     def unit(self) -> Any:
@@ -88,7 +103,6 @@ def unit(self) -> Any:
 
 class Population(Protocol):
     """Population protocol."""
-
     entity: Any
 
     @abc.abstractmethod
@@ -98,7 +112,6 @@ def get_holder(self, variable_name: Any) -> Any:
 
 class Role(Protocol):
     """Role protocol."""
-
     entity: Any
     subroles: Any
 
@@ -125,7 +138,6 @@ def get_population(self, plural: Optional[Any]) -> Any:
 
 class TaxBenefitSystem(Protocol):
     """TaxBenefitSystem protocol."""
-
     person_entity: Any
 
     @abc.abstractmethod
@@ -136,7 +148,17 @@ def get_variable(
         """Abstract method."""
 
 
+class TraceNode(Protocol):
+    """TraceNode protocol."""
+    name: Any
+    value: Any
+    period: Any
+    children: Any
+    parameters: Any
+    formula_time: Any
+    calculation_time: Any
+
+
 class Variable(Protocol):
     """Variable protocol."""
-
     entity: Any
diff --git a/openfisca_tasks/install.mk b/openfisca_tasks/install.mk
index d047a6eb15..50f0a20b55 100644
--- a/openfisca_tasks/install.mk
+++ b/openfisca_tasks/install.mk
@@ -3,16 +3,6 @@ uninstall:
 	@$(call print_help,$@:)
 	@pip freeze | grep -v "^-e" | sed "s/@.*//" | xargs pip uninstall -y
 
-## Install project's overall dependencies
-install-deps:
-	@$(call print_help,$@:)
-	@pip install --upgrade pip twine wheel
-
-## Install project's development dependencies.
-install-edit:
-	@$(call print_help,$@:)
-	@pip install --upgrade --editable ".[dev]"
-
 ## Install project's overall dependencies
 install-deps:
 	@$(call print_help,$@:)
diff --git a/openfisca_tasks/lint.mk b/openfisca_tasks/lint.mk
index 115c6267bb..5e1a6f3d73 100644
--- a/openfisca_tasks/lint.mk
+++ b/openfisca_tasks/lint.mk
@@ -11,7 +11,7 @@ check-syntax-errors: .
 ## Run linters to check for syntax and style errors.
 check-style: $(shell git ls-files "*.py")
 	@$(call print_help,$@:)
-	@flake8 $?
+	@python -m flake8 $?
 	@$(call print_pass,$@:)
 
 ## Run linters to check for syntax and style errors in the doc.
@@ -29,14 +29,14 @@ lint-doc-%:
 	@## able to integrate documentation improvements progresively.
 	@##
 	@$(call print_help,$(subst $*,%,$@:))
-	@flake8 --select=D101,D102,D103,DAR openfisca_core/$*
-	@pylint openfisca_core/$*
+	@python -m flake8 --select=D101,D102,D103,DAR openfisca_core/$*
+	@python -m pylint openfisca_core/$*
 	@$(call print_pass,$@:)
 
 ## Run static type checkers for type errors.
 check-types:
 	@$(call print_help,$@:)
-	@mypy --package openfisca_core --package openfisca_web_api
+	@python -m mypy --package openfisca_core --package openfisca_web_api
 	@$(call print_pass,$@:)
 
 ## Run static type checkers for type errors (strict).
@@ -48,7 +48,7 @@ lint-typing-strict: \
 ## Run static type checkers for type errors (strict).
 lint-typing-strict-%:
 	@$(call print_help,$(subst $*,%,$@:))
-	@mypy \
+	@python -m mypy \
 		--cache-dir .mypy_cache-openfisca_core.$* \
 		--implicit-reexport \
 		--strict \
@@ -58,5 +58,5 @@ lint-typing-strict-%:
 ## Run code formatters to correct style errors.
 format-style: $(shell git ls-files "*.py")
 	@$(call print_help,$@:)
-	@autopep8 $?
+	@python -m autopep8 $?
 	@$(call print_pass,$@:)
diff --git a/openfisca_tasks/test_code.mk b/openfisca_tasks/test_code.mk
index 703cf4ec20..fe83c187f6 100644
--- a/openfisca_tasks/test_code.mk
+++ b/openfisca_tasks/test_code.mk
@@ -4,7 +4,6 @@ openfisca = openfisca_core.scripts.openfisca_command
 ## The path to the installed packages.
 python_packages = $(shell python -c "import sysconfig; print(sysconfig.get_paths()[\"purelib\"])")
 
-<<<<<<< HEAD
 ## Run all tasks required for testing.
 install: install-deps install-edit install-test
 
diff --git a/setup.cfg b/setup.cfg
index 467e3ede59..651df9dda4 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -47,6 +47,7 @@ testpaths           = tests
 ignore_missing_imports = True
 install_types       = True
 non_interactive     = True
+plugins             = numpy.typing.mypy_plugin
 
 [mypy-openfisca_core.commons.tests.*]
 ignore_errors       = True
diff --git a/setup.py b/setup.py
index f2612d44b8..82b53fa731 100644
--- a/setup.py
+++ b/setup.py
@@ -28,7 +28,7 @@
 general_requirements = [
     'dpath >= 1.5.0, < 3.0.0',
     'numexpr >= 2.7.0, <= 3.0',
-    'numpy >= 1.20.3, < 1.23.0',
+    'numpy >= 1.21.6, < 1.23.0',
     'psutil >= 5.4.7, < 6.0.0',
     'pytest >= 4.4.1, < 6.0.0',  # For openfisca test
     'PyYAML >= 3.10',