Add rule for rand(Bool) instead of rand() < 0.5

rules/lang/best-practice/rand_bool.jl

@@ -0,0 +1,21 @@
+#ruleid: rand-bool
+rand() < 0.5
+
+function some_rand_function(x)
+    #ruleid: rand-bool
+    if rand() < 0.5
+        println("Random")
+    end
+end
+
+#ok: rand-bool
+rand() < 0.7  # this is fine
+
+#ok: rand-bool
+flag = rand(Bool)
+
+#ruleid: rand-bool
+if some_flag && rand() < 0.5 || other_flag
+    println("Random")
+end
+

rules/lang/best-practice/rand_bool.yaml

@@ -0,0 +1,14 @@
+rules:
+  - id: rand-bool
+    pattern-either:
+      - pattern: rand() < 0.5
+      - pattern: Base.rand() < 0.5
+    fix: rand(Bool)
+    message: To get a random Boolean, use `rand(Bool)`.
+    languages:
+      - julia
+    severity: WARNING
+    metadata:
+      category: best-practice
+      license: LGPL
+