fixup! refactor: add editor module

Author: mtth

src/git_draft/editor.py

@@ -33,11 +33,11 @@ def open_editor(placeholder="") -> str:
             with open(temp.name, "w") as writer:
                 writer.write(placeholder)
 
-        stdout = open(_get_tty_filename(), "wb")
-        proc = subprocess.Popen(
-            [binpath, temp.name], close_fds=True, stdout=stdout
-        )
-        proc.communicate()
+        with open(_get_tty_filename(), "wb") as stdout:
+            proc = subprocess.Popen(
+                [binpath, temp.name], close_fds=True, stdout=stdout
+            )
+            proc.communicate()
 
         with open(temp.name, mode="r") as reader:
             return reader.read()

tests/git_draft/editor_test.py

@@ -1,4 +1,6 @@
+import pytest
 import shutil
+import subprocess
 
 import git_draft.editor as sut
 
@@ -40,3 +42,30 @@ def which(_editor):
         monkeypatch.setenv("EDITOR", "")
 
         assert sut._guess_editor_binpath() == ""
+
+
+class TestOpenEditor:
+    def test_no_binpath(self, monkeypatch) -> None:
+        def which(_editor):
+            return ""
+
+        monkeypatch.setattr(shutil, "which", which)
+
+        with pytest.raises(ValueError):
+            sut.open_editor()
+
+    def test_ok(self, monkeypatch) -> None:
+        def which(editor):
+            return f"/bin/{editor}"
+
+        class Popen:
+            def __init__(self, *_args, **_kwargs):
+                pass
+
+            def communicate(self):
+                pass
+
+        monkeypatch.setattr(shutil, "which", which)
+        monkeypatch.setattr(subprocess, "Popen", Popen)
+
+        assert sut.open_editor(placeholder="hello") == "hello"