Awesome
Debugger
The missing tools in the Clojure ecosystem.
- break/break-catch: interactive breakpoint
- dbg: debug intermediate expressions
- dbg-defn/dbg-fn: debug incoming arguments
Usage
(use 'debugger.core)
(break (some-fn))
(break-catch (some-raising-fn))
Breakpoints
user=> (dotimes [n 5] (debugger.core-test/foo n))
Break from: /Users/razum2um/Code/debugger/src/debugger/core_test.clj:12 (type "(help)" for help)
17: e (fn [] nil)
18: x "world"
19: y '(8 9)
20: z (Object.)
=> 21: ret (break (inc 42))]
22: (println "Exit foo with" ret)))
Interactive help
debugger.core-test/qux:31=> (h)
(h) (help) prints this help
(wtf) prints short code of breakpointed function
(wtf??) prints full code of breakpointed function
(l) (locals) prints locals
(c) (continue) continues execution, preserves the result and will break here again
(skip 3) skips next 3 breakpoints in this place
(q) (quit) or type Ctrl-D to exit break-repl, pass last result further, will never break here anymore
use (debugger.core/reset-skips!) if breaks are skipped
you can also access locals directly and build sexp with them
any last execution result (but `nil`) before exit will be passed further
if last result is `nil` execution will continue normally
nil
Locals access
debugger.core-test/foo:21=> (l)
{x "world",
a [1 2],
y (8 9),
args nil,
e #<core_test$foo$e__4735 debugger.core_test$foo$e__4735@6735cbba>,
z #<Object java.lang.Object@2094643d>,
h {:k "v"},
b #{4 3},
d nil}
nil
debugger.core-test/foo:21=> z
#<Object java.lang.Object@3dc76ae9>
Return value control
Use any non-nil value to fake inner result:
user=> (debugger.core-test/foo)
Break from: /Users/razum2um/Code/debugger/src/debugger/core_test.clj:12 (type "(help)" for help)
17: e (fn [] nil)
18: x "world"
19: y '(8 9)
20: z (Object.)
=> 21: ret (break (inc 42))]
22: (println "Exit foo with" ret)))
debugger.core-test/foo:21=> 1 ;; inner (inc 42) won't be called
1
debugger.core-test/foo:21=> Exit foo with 1 ;; used result from REPL
nil
Code expection
debugger.core-test/foo:21=> (whereami)
12: (defn foo [& args]
13: (let [a [1 2]
14: b #{3 4}
15: h {:k "v"}
16: d nil
17: e (fn [] nil)
18: x "world"
19: y '(8 9)
20: z (Object.)
=> 21: ret (break (inc 42))]
22: (println "Exit foo with" ret)))
nil
Stack expection
debugger.core-test/foo:21=> (wtf??)
[0] core_test.clj:21 debugger.core-test/foo
[1] RestFn.java:408 clojure.lang.RestFn
[2] form-init1204084863726891616.clj:1 user/eval3682
[3] Compiler.java:6703 clojure.lang.Compiler
[4] Compiler.java:6666 clojure.lang.Compiler
[5] core.clj:2927 clojure.core/eval
[6] main.clj:239 clojure.main/repl
[7] main.clj:239 clojure.main/repl
[8] main.clj:257 clojure.main/repl
[9] main.clj:257 clojure.main/repl
[10] RestFn.java:1523 clojure.lang.RestFn
[11] interruptible_eval.clj:67 clojure.tools.nrepl.middleware.interruptible-eval/evaluate
[12] AFn.java:152 clojure.lang.AFn
[13] AFn.java:144 clojure.lang.AFn
[14] core.clj:624 clojure.core/apply
[15] core.clj:1862 clojure.core/with-bindings*
[16] RestFn.java:425 clojure.lang.RestFn
[17] interruptible_eval.clj:51 clojure.tools.nrepl.middleware.interruptible-eval/evaluate
[18] interruptible_eval.clj:183 clojure.tools.nrepl.middleware.interruptible-eval/interruptible-eval
[19] interruptible_eval.clj:152 clojure.tools.nrepl.middleware.interruptible-eval/run-next
[20] AFn.java:22 clojure.lang.AFn
[21] ThreadPoolExecutor.java:1142 java.util.concurrent.ThreadPoolExecutor
[22] ThreadPoolExecutor.java:617 java.util.concurrent.ThreadPoolExecutor/Worker
[23] Thread.java:745 java.lang.Thread
nil
Break on next (break) or skip it
debugger.core-test/foo:21=> (c)
43
Exit foo with #<Object java.lang.Object@3dc76ae9>
Break from: /Users/razum2um/Code/debugger/src/debugger/core_test.clj:12 (type "(help)" for help)
17: e (fn [] nil)
18: x "world"
19: y '(8 9)
20: z (Object.)
=> 21: ret (break (inc 42))]
22: (println "Exit foo with" ret)))
debugger.core-test/foo:21=> (skip 3)
nil
Exit foo with 43
Exit foo with 43
Exit foo with 43
Break from: /Users/razum2um/Code/debugger/src/debugger/core_test.clj:12 (type "(help)" for help)
17: e (fn [] nil)
18: x "world"
19: y '(8 9)
20: z (Object.)
=> 21: ret (break (inc 42))]
22: (println "Exit foo with" ret)))
debugger.core-test/foo:21=> (c)
43
Exit foo with 43
nil
Breakpoints in threads
user> (debugger.core-test/in-thread)
nil
Registered breakpoint: debugger.core_test$foo$breakpoint__20396__auto____20431@4c18a68e.
Type (breakpoints) to see a list of registered breakpoint, and (connect) to connect to one.
user> (breakpoints)
Breakpoints:
0) debugger.core_test$foo$breakpoint__20396__auto____20431@4c18a68e
nil
user> (connect)
Break from: /Users/maxim/tmp/clj-debugger/src/debugger/core_test.clj:8 (type "(help)" for help)
13: e (fn [] nil)
14: x "world"
15: y '(8 9)
16: z (Object.)
=> 17: ret (break (inc 42))]
18: (println "Exit foo with" ret)))
debugger.core-test/foo:17=> a
[1 2]
debugger.core-test/foo:17=> (q)
Quitting debugger...
nil
nilExit foo with
[1 2]
user>
Configuration
The following dynamic vars are configurable in debugger.config
| Var | Default Value | Use |
|---|---|---|
*break-outside-repl* | true | Break in non-repl threads, since 0.2.0. Default value was false in 0.1.x. |
*code-context-lines* | 5 | Number of lines to include when showing source. |
*locals-print-length* | 10 | Print-length for locals inside the debugger. |
*skip-repl-if-last-quit-ago* | 2 | Number of seconds to wait after a debugger is quit before starting another one. |
TODO
(step),(up),(down)stack manipulation
Debug intermediate expressions
user=> (-> 2 (+ 3) (* 4) dbg (/ 5))
(* (+ 2 3) 4) -> 20
4
Debug incoming arguments
user=> (dbg-defn f1 [arg1 arg2] (+ arg1 arg2))
#'user/f1
user=> (f1 2 3)
{arg1 2, arg2 3}
5
Acknowledgements
- @richhickey for
clojure.main/repl - @GeorgeJahad for the lesson how to preserve locals
- @mveytsman for breakpoints in threads
YourKit
<img src="http://www.yourkit.com/images/yklogo.png"></img>
YourKit has given an open source license for their profiler, greatly simplifying the profiling of ClojureScript performance.
YourKit supports open source projects with its full-featured Java Profiler. YourKit, LLC is the creator of <a href="http://www.yourkit.com/java/profiler/index.jsp">YourKit Java Profiler</a> and <a href="http://www.yourkit.com/.net/profiler/index.jsp">YourKit .NET Profiler</a>, innovative and intelligent tools for profiling Java and .NET applications.
License
Copyright © 2014-2018 Vlad Bokov
Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.