fix: skip account setting upon user request (#224)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **New Features**
- Users can now opt-out from automatic account specification during job
submission using a new configuration flag, offering greater flexibility
for environments with multiple accounts or enforced defaults.
- **Documentation**
- Enhanced guidance on SLURM account management, including advice on
explicitly setting accounts when necessary and details on overriding
default behaviors with a new flag.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: DrYak <[email protected]>

Author: cmeesters

docs/further.md

@@ -18,6 +18,9 @@ To specify them at the command line, define them as default resources:
 $ snakemake --executor slurm --default-resources slurm_account=<your SLURM account> slurm_partition=<your SLURM partition>
 ```
 
+The plugin does its best to _guess_ your account. That might not be possible. Particularly, when dealing with several SLURM accounts, users ought to set them per workflow.
+Some clusters, however, have a pre-defined default per user and _do not_ allow users to set their account or partition. The plugin will always attempt to set an account. To override this behavior, the `--slurm-no-account` flag can be used.
+
 If individual rules require e.g. a different partition, you can override
 the default per rule:
 

snakemake_executor_plugin_slurm/__init__.py

@@ -85,6 +85,15 @@ class ExecutorSettings(ExecutorSettingsBase):
             "required": False,
         },
     )
+    no_account: bool = field(
+        default=False,
+        metadata={
+            "help": "Do not use any account for submission. "
+            "This flag has no effect, if not set.",
+            "env_var": False,
+            "required": False,
+        },
+    )
 
 
 # Required:
@@ -213,7 +222,9 @@ def run_job(self, job: JobExecutorInterface):
             f"--comment '{comment_str}'"
         )
 
-        call += self.get_account_arg(job)
+        if not self.workflow.executor_settings.no_account:
+            call += self.get_account_arg(job)
+
         call += self.get_partition_arg(job)
 
         if self.workflow.executor_settings.requeue:
@@ -634,35 +645,45 @@ def test_account(self, account):
         """
         tests whether the given account is registered, raises an error, if not
         """
-        cmd = f'sacctmgr -n -s list user "{os.environ["USER"]}" format=account%256'
+        cmd = "sshare -U --format Account --noheader"
         try:
             accounts = subprocess.check_output(
                 cmd, shell=True, text=True, stderr=subprocess.PIPE
             )
         except subprocess.CalledProcessError as e:
-            sacctmgr_report = (
-                "Unable to test the validity of the given or guessed "
-                f"SLURM account '{account}' with sacctmgr: {e.stderr}."
+            sshare_report = (
+                "Unable to test the validity of the given or guessed"
+                f" SLURM account '{account}' with sshare: {e.stderr}."
             )
+            accounts = ""
+
+        if not accounts.strip():
+            cmd = f'sacctmgr -n -s list user "{os.environ["USER"]}" format=account%256'
             try:
-                cmd = "sshare -U --format Account --noheader"
                 accounts = subprocess.check_output(
                     cmd, shell=True, text=True, stderr=subprocess.PIPE
                 )
-            except subprocess.CalledProcessError as e2:
-                sshare_report = (
-                    "Unable to test the validity of the given or guessed"
-                    f" SLURM account '{account}' with sshare: {e2.stderr}."
+            except subprocess.CalledProcessError as e:
+                sacctmgr_report = (
+                    "Unable to test the validity of the given or guessed "
+                    f"SLURM account '{account}' with sacctmgr: {e.stderr}."
                 )
                 raise WorkflowError(
-                    f"The 'sacctmgr' reported: '{sacctmgr_report}' "
-                    f"and likewise 'sshare' reported: '{sshare_report}'."
+                    f"The 'sshare' reported: '{sshare_report}' "
+                    f"and likewise 'sacctmgr' reported: '{sacctmgr_report}'."
                 )
 
         # The set() has been introduced during review to eliminate
         # duplicates. They are not harmful, but disturbing to read.
         accounts = set(_.strip() for _ in accounts.split("\n") if _)
 
+        if not accounts:
+            self.logger.warning(
+                f"Both 'sshare' and 'sacctmgr' returned empty results for account "
+                f"'{account}'. Proceeding without account validation."
+            )
+            return ""
+
         if account not in accounts:
             raise WorkflowError(
                 f"The given account {account} appears to be invalid. Available "