Allow use_exec option with expr tasks

docs/tasks/options.rst

@@ -34,7 +34,7 @@ The following options can be configured on your tasks and are not specific to an
 
   .. attention::
 
-    This option is only applicable to **cmd** and **script** tasks, and it implies the task in question cannot be referenced by another task.
+    This option is only applicable to **cmd**, **script**, and **expr** tasks, and it implies the task in question cannot be referenced by another task.
 
 
 Setting task specific environment variables

docs/tasks/task_types/expr.rst

@@ -29,7 +29,7 @@
 Available task options
 ----------------------
 
-``expr`` tasks support all of the :doc:`standard task options <../options>` with the exception of ``use_exec``.
+``expr`` tasks support all of the :doc:`standard task options <../options>`.
 
 The following options are also accepted:
 

poethepoet/task/expr.py

@@ -32,6 +32,7 @@ class ExprTask(PoeTask):
     __options__: Dict[str, Union[Type, Tuple[Type, ...]]] = {
         "imports": list,
         "assert": (bool, int),
+        "use_exec": bool,
     }
 
     def _handle_run(

pyproject.toml

@@ -107,7 +107,7 @@ _clean_docs.script = "shutil:rmtree('docs/_build', ignore_errors=1)"
 
   [tool.poe.tasks.test-quick]
   help = "Run unit and feature tests, excluding slow ones"
-  cmd  = "pytest -m \"not slow\""
+  cmd  = "pytest -m 'not slow'"
 
   [tool.poe.tasks.types]
   help = "Run the type checker"

tests/fixtures/expr_project/pyproject.toml

@@ -7,7 +7,7 @@ args = [{ name = "power_level", positional = true, type = "integer", default = 4
 expr = """"power level is " + (f"only {sys.argv[1]}" if int(sys.argv[1]) <= 9000 else 'over nine thousand!') """
 
 [tool.poe.tasks.expr_with_env_vars]
-expr = "[${VAR_FOO} * int(${VAR_BAR})][0] + (f'{${VAR_BAZ}}')"
+expr = "[${VAR_FOO} * int(${VAR_BAR})][0] + (f'{${VAR_BAZ}}') + '${NOTHING}'"
 
 [tool.poe.tasks.expr_with_imports]
 help    = "check if the argument looks like an email address"
@@ -17,9 +17,10 @@ env.EMAIL.default = 'user@example.com'
 assert = false
 
 [tool.poe.tasks.expr_with_assert]
-expr   = "min_value < 3"
-args   = [{ name = "min_value", positional = true, type = "integer", required = true}]
-assert = true
+expr     = "min_value < 3"
+args     = [{ name = "min_value", positional = true, type = "integer", required = true}]
+assert   = true
+use_exec = true
 
 [tool.poe.tasks]
 _days_since_incident.expr = "0"

tests/test_expr_task.py

@@ -51,7 +51,7 @@ def test_expr_with_env_vars(run_poe_subproc):
     )
     assert (
         result.capture
-        == "Poe => [${VAR_FOO} * int(${VAR_BAR})][0] + (f'{${VAR_BAZ}}')\n"
+        == "Poe => [${VAR_FOO} * int(${VAR_BAR})][0] + (f'{${VAR_BAZ}}') + '${NOTHING}'\n"
     )
     assert result.stdout == "foofooboo\n"
     assert result.stderr == ""