[mod] Change default top-level *config* :min-level from :report -> …

…:trace

A question from a user just highlighted that the current default level behaviour
is unintuitive.

If `*config*` doesn't have any `:min-level` (rare!), that should imply that no minimum
level exists (i.e. any level should be fine). But instead the current behaviour is
flipped (no `:min-level` restricts all but `:report` level logs).

Note that the appender's `:min-level` already defaults to the (intuitively sensible)
`:trace`, so the current behaviour is not only surprising but also inconsistent.

This is a BREAKING CHANGE but should hopefully affect few folks since it's so rare
for anyone to have a `*config*` without an explicit `:min-level`.

src/taoensso/timbre.cljc

@@ -461,7 +461,7 @@
   ([config level ?ns-str ?file ?line msg-type ?err vargs_ ?base-data callsite-id spying?] (-log! config level ?ns-str ?file ?line nil msg-type ?err vargs_ ?base-data callsite-id spying?))
 
   ([config level ?ns-str ?file ?line ?column msg-type ?err vargs_ ?base-data callsite-id spying?]
-   (when (may-log? :report level ?ns-str config)
+   (when (may-log? :trace level ?ns-str config)
      (let [instant (enc/now-dt*)
            context *context*
            vargs   @vargs_

test/taoensso/timbre_tests.cljc

@@ -60,16 +60,16 @@
 
 (deftest levels
   [(testing "Levels.global/basic"
-     [(is (map? (log-data "ns" :trace {:min-level :trace} {} [])) "call >= min")
+     [(is (map? (log-data "ns" :trace {:min-level nil}    {} [])) "call >= default (:trace)")
+      (is (map? (log-data "ns" :trace {:min-level :trace} {} [])) "call >= min")
       (is (nil? (log-data "ns" :trace {:min-level :info}  {} [])) "call <  min")
       (is (map? (log-data "ns" :info  {:min-level :info}  {} [])) "call >= min")
 
       (is (not     (:error-level? (log-data "ns" :info  {:min-level :info}  {} []))))
       (is (boolean (:error-level? (log-data "ns" :error {:min-level :error} {} []))))])
 
    (testing "Levels.global/by-ns"
-     [(is (nil? (log-data "ns.2" :info   {:min-level [["ns.1" :info]                         ]} {} [])) "call <  default")
-      (is (map? (log-data "ns.2" :report {:min-level [["ns.1" :info]                         ]} {} [])) "call >= default")
+     [(is (map? (log-data "ns.2" :trace  {:min-level [["ns.1" :info]                         ]} {} [])) "call >= default (:trace)")
       (is (map? (log-data "ns.2" :info   {:min-level [["ns.1" :warn] ["ns.2"           :info]]} {} [])) "call >= match")
       (is (map? (log-data "ns.2" :info   {:min-level [["ns.1" :warn] [#{"ns.3" "ns.2"} :info]]} {} [])) "call >= match")
       (is (map? (log-data "ns.2" :info   {:min-level [["ns.1" :warn] ["*"              :info]]} {} [])) "call >= *")