Don't crash if we don't have any data for the top-5 barplot

Fixes #1540

CHANGELOG.md

@@ -72,6 +72,8 @@
   - Don't crash for invalid JSON files ([#1652](https://github.com/ewels/MultiQC/issues/1652))
 - **FastQC**
   - Report median read-length for fastqc in addition to mean ([#1745](https://github.com/ewels/MultiQC/pull/1745))
+- **Kaiju**
+  - Don't crash if we don't have any data for the top-5 barplot ([#1540](https://github.com/ewels/MultiQC/issues/1540))
 - **Kallisto**
   - Fix `ZeroDivisionError` when a sample has zero reads ([#1746](https://github.com/ewels/MultiQC/issues/1746))
 - **Kraken**

multiqc/modules/kaiju/kaiju.py

@@ -154,7 +154,7 @@ def kaiju_stats_table(self):
             "scale": "RdYlGn",
         }
         headers["assigned"] = {
-            "title": "{} Reads assigned".format(config.read_count_desc),
+            "title": "{} Reads assigned".format(config.read_count_prefix),
             "description": "Number of reads assigned ({})  at {} rank".format(
                 config.read_count_desc, general_taxo_rank
             ),
@@ -273,6 +273,10 @@ def top_five_barplot(self):
             cats.append(rank_cats)
             pd.append(rank_data)
 
+        if len(cats) == 0:
+            log.debug("No data for Kaiju top five barplot. Skipping.")
+            return
+
         self.add_section(
             name="Top taxa",
             anchor="kaiju-topfive",