handle error when subworkflow does not include any components

nf_core/subworkflows/lint/main_nf.py

@@ -120,32 +120,36 @@ def check_main_section(self, lines, included_components):
 
     # Check that all included components are used
     # Check that all included component versions are used
-    main_nf_include_used = True
-    main_nf_include_versions = True
-    for component in included_components:
-        if component not in script:
-            self.warned.append(
-                (
-                    "main_nf_include_used",
-                    f"Not all included components are used in main.nf",
-                    self.main_nf,
+    main_nf_include_used = False
+    main_nf_include_versions = False
+    if included_components is not None:
+        for component in included_components:
+            if component in script:
+                self.passed.append(
+                    ("main_nf_include_used", f"All included components are used in main.nf", self.main_nf)
                 )
-            )
-            main_nf_include_used = False
-        if component + ".out.versions" not in script:
-            self.warned.append(
-                (
-                    "main_nf_include_versions",
-                    f"Not all included component versions are added in main.nf",
-                    self.main_nf,
+                main_nf_include_used = True
+            if component + ".out.versions" not in script:
+                self.passed.append(
+                    ("main_nf_include_versions", f"All included component versions are added in main.nf", self.main_nf)
                 )
+                main_nf_include_versions = True
+
+    if not main_nf_include_used:
+        self.warned.append(
+            (
+                "main_nf_include_used",
+                f"Not all included components are used in main.nf",
+                self.main_nf,
+            )
+        )
+    if not main_nf_include_versions:
+        self.warned.append(
+            (
+                "main_nf_include_versions",
+                f"Not all included component versions are added in main.nf",
+                self.main_nf,
             )
-            main_nf_include_versions = False
-    if main_nf_include_used:
-        self.passed.append(("main_nf_include_used", f"All included components are used in main.nf", self.main_nf))
-    if main_nf_include_versions:
-        self.passed.append(
-            ("main_nf_include_versions", f"All included component versions are added in main.nf", self.main_nf)
         )