Added OverrideDryrun (#34)

* Added OverrideDryrun

* More tests

* Bump minor version

---------

Co-authored-by: Zoran Simic <zsimic@netflix.com>

docs/history.rst

@@ -2,6 +2,12 @@
 History
 =======
 
+5.2.0 (2024-09-18)
+------------------
+
+* Added ``OverrideDryrun`` context manager
+
+
 5.1.1 (2024-08-12)
 ------------------
 

src/runez/__init__.py

@@ -18,7 +18,7 @@
 from runez.program import check_pid, is_executable, make_executable, PsInfo, run, shell, which
 from runez.serialize import from_json, read_json, represented_json, save_json, Serializable
 from runez.system import abort, abort_if, AdaptedProperty, cached_property, uncolored, Undefined, UNSET, wcswidth
-from runez.system import Anchored, CaptureOutput, CurrentFolder, Slotted, TempArgv, TrackedOutput
+from runez.system import Anchored, CaptureOutput, CurrentFolder, OverrideDryrun, Slotted, TempArgv, TrackedOutput
 from runez.system import capped, decode, DEV, flattened, joined, quoted, resolved_path, short, stringified, SYS_INFO
 from runez.system import first_line, get_version, is_basetype, is_iterable, ltattr
 
@@ -39,7 +39,7 @@
     "check_pid", "is_executable", "make_executable", "PsInfo", "run", "shell", "which",
     "from_json", "read_json", "represented_json", "save_json", "Serializable",
     "abort", "abort_if", "AdaptedProperty", "cached_property", "uncolored", "Undefined", "UNSET", "wcswidth",
-    "Anchored", "CaptureOutput", "CurrentFolder", "Slotted", "TempArgv", "TrackedOutput",
+    "Anchored", "CaptureOutput", "CurrentFolder", "OverrideDryrun", "Slotted", "TempArgv", "TrackedOutput",
     "capped", "decode", "DEV", "flattened", "joined", "quoted", "resolved_path", "short", "stringified", "SYS_INFO",
     "first_line", "get_version", "is_basetype", "is_iterable", "ltattr"
 ]

src/runez/system.py

@@ -997,6 +997,20 @@ def __exit__(self, *_):
             Anchored.pop(self.destination)
 
 
+class OverrideDryrun:
+    """Context manager to temporarily override dryrun mode"""
+
+    def __init__(self, dryrun):
+        self.dryrun = dryrun
+
+    def __enter__(self):
+        self.prior = _R.set_dryrun(self.dryrun)
+        return self.prior
+
+    def __exit__(self, *_):
+        _R.set_dryrun(self.prior)
+
+
 class TrackedOutput:
     """Track captured output"""
 

tests/test_system.py

@@ -567,6 +567,24 @@ def test_system():
     assert str(runez.system.PlatformInfo("Darwin 20.5.0 x86_64 i386")) == "Darwin/20.5.0; x86_64 i386"
     assert str(runez.system.PlatformInfo("Linux 5.10.25 x86_64 x86_64")) == "Linux/5.10.25; x86_64"
 
+    assert runez.DRYRUN is False
+    with runez.OverrideDryrun(True) as prior1:
+        assert runez.DRYRUN is True
+        assert prior1 is False
+        with runez.OverrideDryrun(False) as prior2:
+            # Flip-flopping OK
+            assert runez.DRYRUN is False
+            assert prior2 is True
+
+            with runez.OverrideDryrun(False) as prior3:
+                # Overriding twice with the same value OK
+                assert runez.DRYRUN is False
+                assert prior3 is False
+
+        assert runez.DRYRUN is True
+
+    assert runez.DRYRUN is False
+
     ct = runez.DEV.current_test()
     assert ct
     assert not ct.is_main