fix: preserve empty property values in CLI (#3745)

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# Rationale for this change

The `properties get table` and `properties get namespace` commands used
a truthy check for property lookups. As a result, an existing property
with an empty string value was reported as missing.

This changes both lookups to check explicitly for `None`, preserving
empty strings while keeping the existing error for missing properties.

Related to #3713.

## Are these changes tested?

Yes. Added CLI regression tests for empty table and namespace property
values.

- `make lint`
- `uv run python -m pytest tests/cli/test_console.py`

## Are there any user-facing changes?

Yes. The table and namespace property commands now return an existing
empty string value instead of raising `NoSuchPropertyException`.

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Author: mj006648

pyiceberg/cli/console.py

@@ -327,7 +327,8 @@ def get_namespace(ctx: Context, identifier: str, property_name: str) -> None:
     namespace_properties = catalog.load_namespace_properties(identifier_tuple)
 
     if property_name:
-        if property_value := namespace_properties.get(property_name):
+        property_value = namespace_properties.get(property_name)
+        if property_value is not None:
             output.text(property_value)
         else:
             raise NoSuchPropertyException(f"Could not find property {property_name} on namespace {identifier}")
@@ -348,7 +349,8 @@ def get_table(ctx: Context, identifier: str, property_name: str) -> None:
     metadata = catalog.load_table(identifier_tuple).metadata
 
     if property_name:
-        if property_value := metadata.properties.get(property_name):
+        property_value = metadata.properties.get(property_name)
+        if property_value is not None:
             output.text(property_value)
         else:
             raise NoSuchPropertyException(f"Could not find property {property_name} on table {identifier}")

tests/cli/test_console.py

@@ -440,6 +440,21 @@ def test_properties_get_table_specific_property(catalog: InMemoryCatalog) -> Non
     assert result.output == "134217728\n"
 
 
+def test_properties_get_table_specific_empty_property(catalog: InMemoryCatalog) -> None:
+    catalog.create_namespace(TEST_TABLE_NAMESPACE)
+    catalog.create_table(
+        identifier=TEST_TABLE_IDENTIFIER,
+        schema=TEST_TABLE_SCHEMA,
+        partition_spec=TEST_TABLE_PARTITION_SPEC,
+        properties={"empty": ""},
+    )
+
+    runner = CliRunner()
+    result = runner.invoke(run, ["properties", "get", "table", "default.my_table", "empty"])
+    assert result.exit_code == 0
+    assert result.output == "\n"
+
+
 def test_properties_get_table_specific_property_that_doesnt_exist(catalog: InMemoryCatalog) -> None:
     catalog.create_namespace(TEST_TABLE_NAMESPACE)
     catalog.create_table(
@@ -482,6 +497,15 @@ def test_properties_get_namespace_specific_property(catalog: InMemoryCatalog, na
     assert result.output == "s3://warehouse/database/location\n"
 
 
+def test_properties_get_namespace_specific_empty_property(catalog: InMemoryCatalog) -> None:
+    catalog.create_namespace(TEST_TABLE_NAMESPACE, {"empty": ""})
+
+    runner = CliRunner()
+    result = runner.invoke(run, ["properties", "get", "namespace", "default", "empty"])
+    assert result.exit_code == 0
+    assert result.output == "\n"
+
+
 def test_properties_get_namespace_does_not_exist(catalog: InMemoryCatalog, namespace_properties: Properties) -> None:
     catalog.create_namespace(TEST_TABLE_NAMESPACE, namespace_properties)