Created SC2202 (markdown)

SC2202.md

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+## Globs don't work as operands in [ ]. 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 expand to a sequence of words, one per matching filename. Meanwhile, operators work on single words.
+
+The problematic code is equivalent to `[ current.log -nt backup/file1.log backup/file2.log backup/file3.log ]`, which is invalid syntax.
+
+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.