Convert a PyPI name to conda iff it's a conda dep

Otherwise when we parse non-Poetry pyproject.toml, it always converts
PyPI names to conda names, even if the dep stays as PyPI.

conda_lock/src_parser/environment_yaml.py

@@ -71,7 +71,7 @@ def _parse_environment_file_for_platform(
                 continue
 
             dependency = parse_python_requirement(
-                spec, manager="pip", category=category, normalize_name=False
+                spec, manager="pip", category=category
             )
             if evaluate_marker(dependency.markers, platform):
                 # The above condition will skip adding the dependency if a

conda_lock/src_parser/pyproject_toml.py

@@ -466,14 +466,23 @@ def parse_python_requirement(
     requirement: str,
     manager: Literal["conda", "pip"] = "conda",
     category: str = "main",
-    normalize_name: bool = True,
 ) -> Dependency:
     """Parse a requirements.txt like requirement to a conda spec.
 
     >>> parse_python_requirement("my_package")  # doctest: +NORMALIZE_WHITESPACE
     VersionedDependency(name='my-package', manager='conda', category='main', extras=[],
         markers=None, version='*', build=None, conda_channel=None, hash=None)
 
+    The PyPI name `build` will be translated to `python-build` for conda.
+    >>> parse_python_requirement("build")  # doctest: +NORMALIZE_WHITESPACE
+    VersionedDependency(name='python-build', manager='conda', category='main',
+        extras=[], markers=None, version='*', build=None, conda_channel=None, hash=None)
+
+    No translation is done for `manager="pip"`.
+    >>> parse_python_requirement("build", manager="pip")  # doctest: +NORMALIZE_WHITESPACE
+    VersionedDependency(name='build', manager='pip', category='main',
+        extras=[], markers=None, version='*', build=None, conda_channel=None, hash=None)
+
     >>> parse_python_requirement(
     ...     "My_Package[extra]==1.23"
     ... )  # doctest: +NORMALIZE_WHITESPACE
@@ -513,7 +522,7 @@ def parse_python_requirement(
     if conda_version:
         conda_version = ",".join(sorted(conda_version.split(",")))
 
-    if normalize_name:
+    if manager == "conda":
         conda_dep_name = pypi_name_to_conda_name(name)
     else:
         conda_dep_name = name