WIP: More testing likely breaking py3.6 support

This test will break python 3.6 and I'm likely to drop support for 3.6 because of it.
The test fails because identical pathlib requirements don't compare equal in 3.6.

.github/workflows/python-static-analysis-and-test.yml

@@ -52,15 +52,6 @@ jobs:
         json_ver: ['json', 'json5']
         os: ['ubuntu-latest', 'windows-latest']
         python: ['3.7', '3.8', '3.9', '3.10', '3.11']
-        # Works around the depreciation of python 3.6 for ubuntu
-        # https://github.com/actions/setup-python/issues/544
-        include:
-          - json_ver: 'json'
-            os: 'ubuntu-20.04'
-            python: '3.6'
-          - json_ver: 'json5'
-            os: 'ubuntu-20.04'
-            python: '3.6'
 
     runs-on: ${{ matrix.os }}
 

README.md

@@ -139,7 +139,7 @@ home directory on other platforms.
 
 ## Installing
 
-Hab is installed using pip. It requires python 3.6 or above. It's recommended
+Hab is installed using pip. It requires python 3.7 or above. It's recommended
 that you add the path to your python's bin or Scripts folder to the `PATH`
 environment variable so you can simply run the `hab` command.
 

hab/parsers/lazy_distro_version.py

@@ -9,7 +9,7 @@
 logger = logging.getLogger(__name__)
 
 
-class DistroPaths:
+class DistroPath:
     __slots__ = ("distro", "hab_filename", "root", "site")
 
     def __init__(self, distro, root, relative=NotSet, site=None):
@@ -83,8 +83,8 @@ def install(self, dest, replace=False, relative=NotSet):
                 contains this distro this error is raised and it is not installed.
                 Unless `replace` is set to True.
         """
-        if not isinstance(dest, DistroPaths):
-            dest = DistroPaths(self, dest, relative=relative, site=self.resolver.site)
+        if not isinstance(dest, DistroPath):
+            dest = DistroPath(self, dest, relative=relative, site=self.resolver.site)
 
         installed = self.installed(dest, relative=relative)
         if installed:
@@ -99,8 +99,8 @@ def install(self, dest, replace=False, relative=NotSet):
         self.resolver.clear_caches()
 
     def installed(self, dest, relative=NotSet):
-        if not isinstance(dest, DistroPaths):
-            dest = DistroPaths(self, dest, relative=relative, site=self.resolver.site)
+        if not isinstance(dest, DistroPath):
+            dest = DistroPath(self, dest, relative=relative, site=self.resolver.site)
         return dest.hab_filename.exists()
 
     def _ensure_loaded(self):

setup.cfg

@@ -38,7 +38,7 @@ install_requires =
     importlib-metadata
     packaging>=20.0
     setuptools-scm[toml]>=4
-python_requires = >=3.6
+python_requires = >=3.7
 include_package_data = True
 scripts =
     bin/.hab-complete.bash

tests/test_lazy_distro_version.py

@@ -0,0 +1,151 @@
+import pytest
+from packaging.requirements import Requirement
+from packaging.version import Version
+
+from hab import DistroMode
+from hab.errors import InstallDestinationExistsError
+from hab.parsers.lazy_distro_version import DistroPath, LazyDistroVersion
+
+
+def test_distro_path(zip_distro_sidecar, helpers, tmp_path):
+    resolver = helpers.render_resolver(
+        "site_distro_zip_sidecar.json",
+        tmp_path,
+        zip_root=zip_distro_sidecar.root.as_posix(),
+    )
+    with resolver.distro_mode_override(DistroMode.Downloaded):
+        distro = resolver.find_distro("dist_a==0.2")
+
+    # Passing root as a string converts it to a pathlib.Path object.
+    dpath = DistroPath(
+        distro, str(tmp_path), relative="{distro_name}-v{version}", site=resolver.site
+    )
+    # Test that the custom relative string, it used to generate root
+    assert dpath.root == tmp_path / "dist_a-v0.2"
+    assert dpath.hab_filename == tmp_path / "dist_a-v0.2" / ".hab.json"
+
+    # If site and relative are not passed the default is used
+    dpath = DistroPath(distro, tmp_path)
+    assert dpath.root == tmp_path / "dist_a" / "0.2"
+    assert dpath.hab_filename == tmp_path / "dist_a" / "0.2" / ".hab.json"
+
+    # Test that site settings are respected when not passing relative
+    resolver.site.downloads["relative_path"] = "parent/{distro_name}/child/{version}"
+    dpath = DistroPath(distro, tmp_path, site=resolver.site)
+    assert dpath.root == tmp_path / "parent" / "dist_a" / "child" / "0.2"
+    assert (
+        dpath.hab_filename
+        == tmp_path / "parent" / "dist_a" / "child" / "0.2" / ".hab.json"
+    )
+
+
+def test_is_lazy(zip_distro_sidecar, helpers, tmp_path):
+    """Check that a LazyDistroVersion doesn't automatically load all data."""
+    resolver = helpers.render_resolver(
+        "site_distro_zip_sidecar.json",
+        tmp_path,
+        zip_root=zip_distro_sidecar.root.as_posix(),
+    )
+    with resolver.distro_mode_override(DistroMode.Downloaded):
+        distro = resolver.find_distro("dist_a==0.1")
+
+    frozen_data = dict(
+        context=["dist_a"],
+        name="dist_a==0.1",
+        version=Version("0.1"),
+    )
+    filename = zip_distro_sidecar.root / "dist_a_v0.1.hab.json"
+
+    # The find_distro call should have called load but does not actually load data
+    assert isinstance(distro, LazyDistroVersion)
+    assert distro._loaded is False
+    assert distro.context == ["dist_a"]
+    assert distro.filename == filename
+    assert distro.frozen_data == frozen_data
+    assert distro.name == "dist_a==0.1"
+
+    # Calling _ensure_loaded actually loads the full distro from the finder's data
+    data = distro._ensure_loaded()
+    assert distro._loaded is True
+    assert isinstance(data, dict)
+    assert distro.name == "dist_a==0.1"
+
+    # If called a second time, then nothing extra is done and no data is returned.
+    assert distro._ensure_loaded() is None
+
+
+def test_bad_kwargs():
+    """Test that the proper error is raised if you attempt to init with a filename."""
+    match = "Passing filename to this class is not supported."
+    with pytest.raises(ValueError, match=match):
+        LazyDistroVersion(None, None, "filename")
+
+    with pytest.raises(ValueError, match=match):
+        LazyDistroVersion(None, None, filename="a/filename")
+
+
+@pytest.mark.parametrize(
+    "prop,check",
+    (("distros", {"dist_b": Requirement("dist_b")}),),
+)
+def test_lazy_hab_property(prop, check, zip_distro_sidecar, helpers, tmp_path):
+    """Check that a LazyDistroVersion doesn't automatically load all data."""
+    resolver = helpers.render_resolver(
+        "site_distro_zip_sidecar.json",
+        tmp_path,
+        zip_root=zip_distro_sidecar.root.as_posix(),
+    )
+    with resolver.distro_mode_override(DistroMode.Downloaded):
+        distro = resolver.find_distro("dist_a==0.2")
+
+    # Calling a lazy getter ensures the data is loaded
+    assert distro._loaded is False
+    value = getattr(distro, prop)
+    assert distro._loaded is True
+    assert value == check
+
+    # You can call the lazy getter repeatedly
+    value = getattr(distro, prop)
+    assert value == check
+
+
+def test_install(zip_distro_sidecar, helpers, tmp_path):
+    """Check that a LazyDistroVersion doesn't automatically load all data."""
+    resolver = helpers.render_resolver(
+        "site_distro_zip_sidecar.json",
+        tmp_path,
+        zip_root=zip_distro_sidecar.root.as_posix(),
+    )
+    with resolver.distro_mode_override(DistroMode.Downloaded):
+        distro = resolver.find_distro("dist_a==0.2")
+    dest_root = resolver.site.downloads["install_root"]
+    distro_root = dest_root / "dist_a" / "0.2"
+    hab_json = distro_root / ".hab.json"
+
+    # The distro is not currently installed. This also tests that it can
+    # auto-cast to DistroPath
+    assert not distro.installed(dest_root)
+
+    # Install will clear the cache, ensure its populated
+    assert resolver._downloadable_distros is not None
+    # Install the distro using LazyDistroVersion
+    distro.install(dest_root)
+    assert distro.installed(dest_root)
+    assert hab_json.exists()
+    # Check that the cache was cleared by the install function
+    assert resolver._downloadable_distros is None
+
+    # Test that if the distro is already installed, an error is raised
+    with pytest.raises(InstallDestinationExistsError) as excinfo:
+        distro.install(dest_root)
+    assert excinfo.value.filename == distro_root
+
+    # Test forced replacement of an existing distro by creating an extra file
+    extra_file = distro_root / "extra_file.txt"
+    extra_file.touch()
+    # This won't raise the exception, but will remove the old distro
+    distro.install(dest_root, replace=True)
+    assert hab_json.exists()
+    assert distro.installed(dest_root)
+
+    assert not extra_file.exists()

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = begin,py{36,37,38,39,310,311}-{json,json5},end,black,flake8
+envlist = begin,py{37,38,39,310,311}-{json,json5},end,black,flake8
 skip_missing_interpreters = True
 skipsdist = True
 
@@ -29,14 +29,14 @@ commands =
 
     coverage erase
 
-[testenv:py{36,37,38,39,310,311}-{json,json5}]
+[testenv:py{37,38,39,310,311}-{json,json5}]
 depends = begin
 
 [testenv:end]
 basepython = python3
 depends =
     begin
-    py{36,37,38,39,310,311}-{json,json5}
+    py{37,38,39,310,311}-{json,json5}
 parallel_show_output = True
 deps =
     coverage