build: fix Taskfile.yml for Windows (#2064)

Fix some issues that the Taskfile had on Windows, mostly related to
shell quoting. Mainly doing this because I'm trying to fix some Windows
specific issues and tasks in the Taskfile make it easier to work on
Windows provided they work correctly.

Other changes:
- Add a separate task for creating a venv.

Taskfile.yml

@@ -59,17 +59,17 @@ tasks:
   install:tox:
     desc: Install tox
     cmds:
-      - '{{._PYTHON}} -m pip install tox {{if (mustFromJson .WITH_GITHUB_ACTIONS)}}tox-gh-actions{{end}}'
+      - '{{._PYTHON | shellQuote}} -m pip install tox {{if (mustFromJson .WITH_GITHUB_ACTIONS)}}tox-gh-actions{{end}}'
 
   install:pip-deps:
     desc: Install pip dependencies
     cmds:
-      - '{{._PYTHON}} -m pip install --upgrade -r requirements.txt -r requirements.dev.txt -r docs/sphinx-requirements.txt {{if (mustFromJson .INSTALL_PIP_EXTRAS)}}-r requirements.dev-extras.txt{{end}}'
+      - '{{._PYTHON | shellQuote}} -m pip install --upgrade -r requirements.txt -r requirements.dev.txt -r docs/sphinx-requirements.txt {{if (mustFromJson .INSTALL_PIP_EXTRAS)}}-r requirements.dev-extra.txt{{end}}'
 
   install:flake8:
     desc: Install flake8 dependencies
     cmds:
-      - "{{._PYTHON}} -m pip install --upgrade -r requirements.flake8.txt"
+      - "{{._PYTHON | shellQuote}} -m pip install --upgrade -r requirements.flake8.txt"
 
   install:deps:
     desc: Install all dependencies
@@ -78,10 +78,16 @@ tasks:
       - task: install:tox
       - task: install:pip-deps
 
+
+  venv:create:
+    desc: Create a venv to VENV_PATH(={{.VENV_PATH}})
+    cmds:
+      - "{{.PYTHON | shellQuote}} -m venv {{.VENV_PATH}}"
+
   venv:install:
-    desc: Install a venv to VENV_PATH(={{.VENV_PATH}})
+    desc: Create and install a venv to VENV_PATH(={{.VENV_PATH}})
     cmds:
-      - "{{.PYTHON}} -m venv {{.VENV_PATH}}"
+      - task: venv:create
       - task: install:pip-deps
         vars: { _PYTHON: "{{.VENV_PYTHON}}" }
 
@@ -116,33 +122,33 @@ tasks:
         {{if .TOX_EXTRA_COMMAND}}TOX_EXTRA_COMMAND={{shellQuote .TOX_EXTRA_COMMAND}}{{end}} \
         {{if .COVERAGE_FILE}}COVERAGE_FILE={{shellQuote .COVERAGE_FILE}}{{end}} \
         {{.TEST_HARNESS}} \
-        {{._PYTHON}} \
+        {{._PYTHON | shellQuote}} \
           -m tox \
           {{.CLI_ARGS}}
     env:
       TOXENV: '{{if .TOX_PYTHON_VERSION}}py{{mustRegexReplaceAll "^([0-9]+)[.]([0-9]+).*" .TOX_PYTHON_VERSION "${1}${2}"}}{{if (mustFromJson .EXTENSIVE)}}-extensive{{end}}{{.TOXENV_SUFFIX | default ""}}{{end}}'
   test:
     desc: Run tests
     cmds:
-      - '{{.TEST_HARNESS}}{{.VENV_BINPREFIX}}pytest {{if (mustFromJson .WITH_COVERAGE)}}--cov --cov-report={{end}} {{.CLI_ARGS}}'
+      - '{{.TEST_HARNESS}}{{print .VENV_BINPREFIX "pytest" | shellQuote}} {{if (mustFromJson .WITH_COVERAGE)}}--cov --cov-report={{end}} {{.CLI_ARGS}}'
 
   flake8:
     desc: Run flake8
     cmds:
-      - "{{._PYTHON}} -m flakeheaven lint {{.CLI_ARGS}}"
+      - "{{._PYTHON | shellQuote}} -m flakeheaven lint {{.CLI_ARGS}}"
 
   black:
     desc: Run black
     cmds:
-      - '{{._PYTHON}} -m black {{if (mustFromJson (.CHECK | default "false"))}}--check --diff {{end}}{{.CLI_ARGS | default "."}}'
+      - '{{._PYTHON | shellQuote}} -m black {{if (mustFromJson (.CHECK | default "false"))}}--check --diff {{end}}{{.CLI_ARGS | default "."}}'
   isort:
     desc: Run isort
     cmds:
-      - '{{._PYTHON}} -m isort {{if (mustFromJson (.CHECK | default "false"))}}--check --diff {{end}}{{.CLI_ARGS | default "."}}'
+      - '{{._PYTHON | shellQuote}} -m isort {{if (mustFromJson (.CHECK | default "false"))}}--check --diff {{end}}{{.CLI_ARGS | default "."}}'
   mypy:
     desc: Run mypy
     cmds:
-      - "{{._PYTHON}} -m mypy --show-error-context --show-error-codes"
+      - "{{._PYTHON | shellQuote}} -m mypy --show-error-context --show-error-codes"
 
   lint:fix:
     desc: Fix auto-fixable linting errors
@@ -186,7 +192,7 @@ tasks:
     desc: Build documentation
     cmds:
       - echo "PYTHONPATH=${PYTHONPATH}"
-      - "{{._PYTHON}} -m sphinx.cmd.build -b html -d docs/_build/doctrees docs/ docs/_build/html -W {{.CLI_ARGS}}"
+      - "{{._PYTHON | shellQuote}} -m sphinx.cmd.build -b html -d docs/_build/doctrees docs/ docs/_build/html -W {{.CLI_ARGS}}"
 
   docs:live-server:
     desc: Run a live server on generated docs
@@ -257,7 +263,7 @@ tasks:
       - task: install:tox
         vars:
           WITH_GITHUB_ACTIONS: true
-      - cmd: "{{._PYTHON}} -m pip install coveralls"
+      - cmd: "{{._PYTHON | shellQuote}} -m pip install coveralls"
       - task: tox
         vars:
           COVERAGE_FILE: ".coverage"
@@ -276,7 +282,7 @@ tasks:
     # a python interpreter. The name is inspired by
     # <https://www.npmjs.com/package/rimraf>.
     - cmd: |
-        {{._PYTHON}} -c '
+        {{._PYTHON | shellQuote}} -c '
         from pathlib import Path;
         import sys, shutil;
         for path in sys.argv[1:]: