Add raw attribute to env.set command (#38465)

Update `env.set` command and underlying `SetEnv` object to add the `raw`
boolean attribute. `raw` is optional and set to False by default. When
set to True, value format is skipped for object when generating
environment modifications.

With this change it is now possible to define environment variable
whose value contains variable reference syntax (like `{foo}` or `{}`)
that should be set as-is.

Fixes #29578

lib/spack/spack/modules/common.py

@@ -671,6 +671,12 @@ def configure_options(self):
         # the configure option section
         return None
 
+    def modification_needs_formatting(self, modification):
+        """Returns True if environment modification entry needs to be formatted."""
+        return (
+            not isinstance(modification, (spack.util.environment.SetEnv)) or not modification.raw
+        )
+
     @tengine.context_property
     @memoized
     def environment_modifications(self):
@@ -734,11 +740,12 @@ def environment_modifications(self):
             _check_tokens_are_valid(x.name, message=msg)
             # Transform them
             x.name = spec.format(x.name, transform=transform)
-            try:
-                # Not every command has a value
-                x.value = spec.format(x.value)
-            except AttributeError:
-                pass
+            if self.modification_needs_formatting(x):
+                try:
+                    # Not every command has a value
+                    x.value = spec.format(x.value)
+                except AttributeError:
+                    pass
             x.name = str(x.name).replace("-", "_")
 
         return [(type(x).__name__, x) for x in env if x.name not in exclude]

lib/spack/spack/test/modules/lmod.py

@@ -198,6 +198,15 @@ def test_manpath_setup(self, modulefile_content, module_configuration):
         assert len([x for x in content if 'setenv("MANPATH", "/path/to/man")' in x]) == 1
         assert len([x for x in content if 'append_path("MANPATH", "", ":")' in x]) == 0
 
+    @pytest.mark.regression("29578")
+    def test_setenv_raw_value(self, modulefile_content, module_configuration):
+        """Tests that we can set environment variable value without formatting it."""
+
+        module_configuration("autoload_direct")
+        content = modulefile_content("module-setenv-raw")
+
+        assert len([x for x in content if 'setenv("FOO", "{{name}}, {name}, {{}}, {}")' in x]) == 1
+
     def test_help_message(self, modulefile_content, module_configuration):
         """Tests the generation of module help message."""
 

lib/spack/spack/test/modules/tcl.py

@@ -182,6 +182,15 @@ def test_manpath_setup(self, modulefile_content, module_configuration):
         assert len([x for x in content if 'setenv MANPATH "/path/to/man"' in x]) == 1
         assert len([x for x in content if 'append-path --delim ":" MANPATH ""' in x]) == 0
 
+    @pytest.mark.regression("29578")
+    def test_setenv_raw_value(self, modulefile_content, module_configuration):
+        """Tests that we can set environment variable value without formatting it."""
+
+        module_configuration("autoload_direct")
+        content = modulefile_content("module-setenv-raw")
+
+        assert len([x for x in content if 'setenv FOO "{{name}}, {name}, {{}}, {}"' in x]) == 1
+
     def test_help_message(self, modulefile_content, module_configuration):
         """Tests the generation of module help message."""
 

lib/spack/spack/util/environment.py

@@ -340,13 +340,20 @@ def execute(self, env: MutableMapping[str, str]):
 
 
 class SetEnv(NameValueModifier):
-    __slots__ = ("force",)
+    __slots__ = ("force", "raw")
 
     def __init__(
-        self, name: str, value: str, *, trace: Optional[Trace] = None, force: bool = False
+        self,
+        name: str,
+        value: str,
+        *,
+        trace: Optional[Trace] = None,
+        force: bool = False,
+        raw: bool = False,
     ):
         super().__init__(name, value, trace=trace)
         self.force = force
+        self.raw = raw
 
     def execute(self, env: MutableMapping[str, str]):
         tty.debug(f"SetEnv: {self.name}={str(self.value)}", level=3)
@@ -490,15 +497,16 @@ def _trace(self) -> Optional[Trace]:
         return Trace(filename=filename, lineno=lineno, context=current_context)
 
     @system_env_normalize
-    def set(self, name: str, value: str, *, force: bool = False):
+    def set(self, name: str, value: str, *, force: bool = False, raw: bool = False):
         """Stores a request to set an environment variable.
 
         Args:
             name: name of the environment variable
             value: value of the environment variable
             force: if True, audit will not consider this modification a warning
+            raw: if True, format of value string is skipped
         """
-        item = SetEnv(name, value, trace=self._trace(), force=force)
+        item = SetEnv(name, value, trace=self._trace(), force=force, raw=raw)
         self.env_modifications.append(item)
 
     @system_env_normalize

var/spack/repos/builtin.mock/packages/module-setenv-raw/package.py

@@ -0,0 +1,16 @@
+# Copyright 2013-2023 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack.package import *
+
+
+class ModuleSetenvRaw(Package):
+    homepage = "http://www.llnl.gov"
+    url = "http://www.llnl.gov/module-setenv-raw-1.0.tar.gz"
+
+    version("1.0", "0123456789abcdef0123456789abcdef")
+
+    def setup_run_environment(self, env):
+        env.set("FOO", "{{name}}, {name}, {{}}, {}", raw=True)