--no-truncate flag in show command (#9580)

docs/cli.md

@@ -1061,6 +1061,7 @@ required by
 * `--outdated (-o)`: Show the latest version but only for packages that are outdated.
 * `--all (-a)`: Show all packages (even those not compatible with current system).
 * `--top-level (-T)`: Only show explicitly defined packages.
+* `--no-truncate`: Do not truncate the output based on the terminal width.
 
 {{% note %}}
 When `--only` is specified, `--with` and `--without` options are ignored.

src/poetry/console/commands/show.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+import sys
+
 from typing import TYPE_CHECKING
 from typing import ClassVar
 
@@ -64,6 +66,11 @@ class ShowCommand(GroupCommand, EnvCommand):
             "Show all packages (even those not compatible with current system).",
         ),
         option("top-level", "T", "Show only top-level dependencies."),
+        option(
+            "no-truncate",
+            None,
+            "Do not truncate the output based on the terminal width.",
+        ),
     ]
 
     help = """The show command displays detailed information about a package, or
@@ -229,7 +236,11 @@ def _display_packages_information(
         show_latest = self.option("latest")
         show_all = self.option("all")
         show_top_level = self.option("top-level")
-        width = shutil.get_terminal_size().columns
+        width = (
+            sys.maxsize
+            if self.option("no-truncate")
+            else shutil.get_terminal_size().columns
+        )
         name_length = version_length = latest_length = required_by_length = 0
         latest_packages = {}
         latest_statuses = {}

tests/console/commands/test_show.py

@@ -1981,6 +1981,66 @@ def test_show_required_by_deps(
     assert actual == expected
 
 
+@pytest.mark.parametrize("truncate", [False, True])
+def test_show_entire_description_truncate(
+    tester: CommandTester, poetry: Poetry, installed: Repository, truncate: str
+) -> None:
+    poetry.package.add_dependency(Factory.create_dependency("cachy", "^0.2.0"))
+
+    cachy2 = get_package("cachy", "0.2.0")
+    cachy2.add_dependency(Factory.create_dependency("msgpack-python", ">=0.5 <0.6"))
+
+    installed.add_package(cachy2)
+
+    assert isinstance(poetry.locker, TestLocker)
+    poetry.locker.mock_lock_data(
+        {
+            "package": [
+                {
+                    "name": "cachy",
+                    "version": "0.2.0",
+                    "description": "This is a veeeeeeeery long description that might be truncated.",
+                    "category": "main",
+                    "optional": False,
+                    "platform": "*",
+                    "python-versions": "*",
+                    "checksum": [],
+                    "dependencies": {"msgpack-python": ">=0.5 <0.6"},
+                },
+                {
+                    "name": "msgpack-python",
+                    "version": "0.5.1",
+                    "description": "",
+                    "category": "main",
+                    "optional": False,
+                    "platform": "*",
+                    "python-versions": "*",
+                    "checksum": [],
+                },
+            ],
+            "metadata": {
+                "python-versions": "*",
+                "platform": "*",
+                "content-hash": "123456789",
+                "files": {"cachy": [], "msgpack-python": []},
+            },
+        }
+    )
+
+    tester.execute("" if truncate else "--no-truncate")
+
+    if truncate:
+        expected = """\
+cachy              0.2.0 This is a veeeeeeeery long description that might ...
+msgpack-python (!) 0.5.1"""
+    else:
+        expected = """\
+cachy              0.2.0 This is a veeeeeeeery long description that might be truncated.
+msgpack-python (!) 0.5.1"""
+
+    assert tester.io.fetch_output().strip() == expected
+
+
 def test_show_errors_without_lock_file(tester: CommandTester, poetry: Poetry) -> None:
     assert not poetry.locker.lock.exists()