mapping step: no metat output if no metat data given

workflow/steps/mapping.smk

@@ -12,7 +12,7 @@ rule MAPPING:
         metat=expand(
             os.path.join(RESULTS_DIR, "mapping/metat/{rtype_tool}.bam"),
             rtype_tool=["{r}/{t}/ASSEMBLY_sr".format(r=r, t=t) for r, t in READ_ASSEMBLERS]
-        )
+        ) if "metat" in META_TYPES else []
     output:
         touch("status/mapping.done")
 
@@ -25,7 +25,7 @@ rule COVERAGE:
         metat=expand(
             os.path.join(RESULTS_DIR, "mapping/metat/{rtype_tool}.cov.ave.txt"),
             rtype_tool=["{r}/{t}/ASSEMBLY_sr".format(r=r, t=t) for r, t in READ_ASSEMBLERS]
-        )
+        ) if "metat" in META_TYPES else []
     output:
         touch("status/coverage.done")
 
@@ -40,6 +40,6 @@ rule MAPPABILITY:
             os.path.join(RESULTS_DIR, "mapping/metat/{rtype_tool}.{ext}"),
             rtype_tool=["{r}/{t}/ASSEMBLY_sr".format(r=r, t=t) for r, t in READ_ASSEMBLERS],
             ext=["flagstat.txt", "idxstats.txt", "unique.txt"]
-        )
+        ) if "metat" in META_TYPES else []
     output:
         touch("status/mappability.done")