Created SC2203 (markdown)

SC2203.md

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+## Globs are ignored in [[ ]] except right of =/!=. Use a loop.
+
+### Problematic code:
+
+```sh
+[[ current.log -nt backup/*.log ]] && echo "This is the latest file"
+
+```
+
+### Correct code:
+
+```sh
+newerThanAll=true
+for log in backup/*.log
+do
+  [[ current.log -nt "$log" ]] || newerThanAll=false
+done
+[[ "$newerThanAll" = "true" ]] && echo "This is the latest file"
+```
+
+### Rationale:
+
+Globs in `[[ ]]` will not filename expand, and will be treated literally (or as patterns on the right-hand side of `=`, `==` and `!=`).
+
+The problematic code is equivalent to `[[ current.log -nt 'backup/*.png' ]`, and will look for a file with a literal asterisk in the name.
+
+Instead, you can iterate over the filenames you want with a loop, and apply your condition to each filename.
+
+### Exceptions:
+
+If you know your glob will only ever match one file, you can check this explicitly and use the first file:
+
+```
+set -- backup/*.log
+[[ $# -eq 1 ]] || { echo "There are too many matches."; exit 1; }
+[[ file.log -nt "$1" ]] && echo "This is the latest file"
+```
+
+Alternatively, [[ignore]] this warning.