adding (chibi log) tests

lib/chibi/log-test.sld

@@ -0,0 +1,41 @@
+
+(define-library (chibi log-test)
+  (export run-tests)
+  (import (scheme base) (scheme inexact) (srfi 130)
+          (chibi log) (chibi show) (chibi test))
+  (begin
+    (define-syntax log->string
+      (syntax-rules ()
+        ((log->string expr ...)
+         (let ((out (open-output-string)))
+           (parameterize ((current-error-port out))
+             (log-open default-logger)
+             expr ...
+             (get-output-string out))))))
+    (define-syntax log->string/no-dates
+      (syntax-rules ()
+        ((log->string/no-dates expr ...)
+         (string-join
+          (map (lambda (line) (substring line 20))
+               (string-split (log->string expr ...) "\n"))
+          "\n"))))
+    (define (run-tests)
+      (test-begin "(chibi log)")
+      (test "D four: 4"
+          (log->string/no-dates
+           (log-debug "four: " (+ 2 2))))
+      (test "I pi: 3.14"
+          (log->string/no-dates
+           (log-info "pi: " (with ((precision 2)) (acos -1)))))
+      (test-assert
+        (string-prefix? "E "
+                        (log->string/no-dates
+                         (with-logged-errors (/ 1 0)))))
+      (test "W warn\nE error"
+          (log->string/no-dates
+           (with-log-level
+            'warn
+            (log-info "info")
+            (log-warn "warn")
+            (log-error "error"))))
+      (test-end))))

lib/chibi/log.scm

@@ -24,6 +24,16 @@
 (define (logger-current-level-set! logger level)
   (%logger-current-level-set! logger (log-level-index logger level)))
 
+(define-syntax with-log-level
+  (syntax-rules ()
+    ((with-logger-level level expr0 expr1 ...)
+     (let* ((orig-level (logger-current-level default-logger))
+            (new-level (log-level-index default-logger level)))
+       (dynamic-wind
+         (lambda () (%logger-current-level-set! default-logger new-level))
+         (lambda () expr0 expr1 ...)
+         (lambda () (%logger-current-level-set! default-logger orig-level)))))))
+
 (define-syntax define-logger
   (syntax-rules ()
     ((define-logger logger (levels ...))

lib/chibi/log.sld

@@ -20,7 +20,8 @@
    log-level-index log-level-name log-level-abbrev
    ;; the default logger
    default-logger log-emergency log-alert log-critical log-error
-   log-warn log-notice log-info log-debug)
+   log-warn log-notice log-info log-debug
+   with-log-level)
   (import (chibi time) (chibi string) (chibi show base))
   (cond-expand
    (chibi