fix: format output of config printvalue as yaml

changelog.d/20230412_100608_regis_palm.md

@@ -15,3 +15,4 @@
     - [Improvement] The `IMAGES_BUILD` filter now supports relative paths as strings, and not just as tuple of strings.
     - [Improvement] Auto-complete the image names in the `images build/pull/push/printtag` commands.
     - [Deprecation] For local installations, Docker v20.10.15 and Compose v2.0.0 are now the minimum required versions.
+    - [Bugfix] Make `tutor config printvalue ...` print actual yaml-formatted values, such as "true" and "null"

tests/test_serialize.py

@@ -41,3 +41,17 @@ def test_parse_key_value(self) -> None:
                 "x=key1:\n  subkey: value\nkey2:\n  subkey: value"
             ),
         )
+
+    def test_str_format(self) -> None:
+        self.assertEqual("true", serialize.str_format(True))
+        self.assertEqual("false", serialize.str_format(False))
+        self.assertEqual("null", serialize.str_format(None))
+        self.assertEqual("éü©", serialize.str_format("éü©"))
+        self.assertEqual("""[1, 'abcd']""", serialize.str_format([1, "abcd"]))
+
+    def test_load_str_format(self) -> None:
+        self.assertEqual(True, serialize.load(serialize.str_format(True)))
+        self.assertEqual(False, serialize.load(serialize.str_format(False)))
+        self.assertEqual(None, serialize.load(serialize.str_format(None)))
+        self.assertEqual("éü©", serialize.load(serialize.str_format("éü©")))
+        self.assertEqual([1, "abcd"], serialize.load(serialize.str_format([1, "abcd"])))

tutor/commands/config.py

@@ -198,10 +198,10 @@ def printroot(context: Context) -> None:
 def printvalue(context: Context, key: str) -> None:
     config = tutor_config.load(context.root)
     try:
-        # Note that this will incorrectly print None values
-        fmt.echo(str(config[key]))
+        value = config[key]
     except KeyError as e:
         raise exceptions.TutorError(f"Missing configuration value: {key}") from e
+    fmt.echo(serialize.str_format(value))
 
 
 @click.group(name="patches", help="Commands related to patches in configurations")

tutor/commands/mounts.py

@@ -5,11 +5,12 @@
 import click
 import yaml
 
-from tutor import bindmount, exceptions, fmt, hooks
-from tutor.commands.context import Context
-from tutor.commands.params import ConfigLoaderParam
+from tutor import bindmount
 from tutor import config as tutor_config
+from tutor import exceptions, fmt, hooks
 from tutor.commands.config import save as config_save
+from tutor.commands.context import Context
+from tutor.commands.params import ConfigLoaderParam
 
 
 class MountParamType(ConfigLoaderParam):

tutor/serialize.py

@@ -18,19 +18,36 @@ def load_all(stream: str) -> t.Iterator[t.Any]:
 
 
 def dump_all(documents: t.Sequence[t.Any], fileobj: TextIOWrapper) -> None:
-    yaml.safe_dump_all(documents, stream=fileobj, default_flow_style=False)
+    yaml.safe_dump_all(
+        documents, stream=fileobj, default_flow_style=False, allow_unicode=True
+    )
 
 
 def dump(content: t.Any, fileobj: TextIOWrapper) -> None:
-    yaml.dump(content, stream=fileobj, default_flow_style=False)
+    yaml.dump(content, stream=fileobj, default_flow_style=False, allow_unicode=True)
 
 
 def dumps(content: t.Any) -> str:
-    result = yaml.dump(content, default_flow_style=False)
+    result = yaml.dump(content, default_flow_style=False, allow_unicode=True)
     assert isinstance(result, str)
     return result
 
 
+def str_format(content: t.Any) -> str:
+    """
+    Convert a value to str.
+
+    This is almost like json, but more convenient for printing to the standard output.
+    """
+    if content is True:
+        return "true"
+    if content is False:
+        return "false"
+    if content is None:
+        return "null"
+    return str(content)
+
+
 def parse(v: t.Union[str, t.IO[str]]) -> t.Any:
     """
     Parse a yaml-formatted string.