bitbake: ui/knotty: print log paths for failed tasks in summary

When tasks fail, it's very frustrating to have to scroll up to find the
log path(s). Many of us have the muscle memory to navigate to the 'temp'
directories under tmp/work/, but new users do not.

This change enhances the final summary to include log paths (reported
via bb.build.TaskFailed events). Here's an example:

NOTE: Tasks Summary: Attempted 856 tasks of which 853 didn't need to be rerun and 3 failed.

Summary: 3 tasks failed:
  virtual:native:/home/chris/repos/poky/meta/recipes-core/ncurses/ncurses_6.5.bb:do_fetch
    log: /home/chris/repos/poky/build/tmp/work/x86_64-linux/ncurses-native/6.5/temp/log.do_fetch.1253462
  /home/chris/repos/poky/meta/recipes-core/ncurses/ncurses_6.5.bb:do_fetch
    log: /home/chris/repos/poky/build/tmp/work/core2-64-poky-linux/ncurses/6.5/temp/log.do_fetch.1253466
  virtual:nativesdk:/home/chris/repos/poky/meta/recipes-core/ncurses/ncurses_6.5.bb:do_fetch
    log: /home/chris/repos/poky/build/tmp/work/x86_64-nativesdk-pokysdk-linux/nativesdk-ncurses/6.5/temp/log.do_fetch.1253467
Summary: There were 3 WARNING messages.
Summary: There were 6 ERROR messages, returning a non-zero exit code.

Each log is rendered as a clickable hyperlink in the terminal. See
https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda

(Bitbake rev: 9c020cc314bfd0702bb1d457d94925c6e9613268)

Signed-off-by: Chris Laplante <chris.laplante@agilent.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

bitbake/lib/bb/ui/knotty.py

@@ -640,7 +640,7 @@ def main(server, eventHandler, params, tf = TerminalFilter):
     return_value = 0
     errors = 0
     warnings = 0
-    taskfailures = []
+    taskfailures = {}
 
     printintervaldelta = 10 * 60 # 10 minutes
     printinterval = printintervaldelta
@@ -726,6 +726,8 @@ def main(server, eventHandler, params, tf = TerminalFilter):
             if isinstance(event, bb.build.TaskFailed):
                 return_value = 1
                 print_event_log(event, includelogs, loglines, termfilter)
+                k = "{}:{}".format(event._fn, event._task)
+                taskfailures[k] = event.logfile
             if isinstance(event, bb.build.TaskBase):
                 logger.info(event._message)
                 continue
@@ -821,7 +823,7 @@ def main(server, eventHandler, params, tf = TerminalFilter):
 
             if isinstance(event, bb.runqueue.runQueueTaskFailed):
                 return_value = 1
-                taskfailures.append(event.taskstring)
+                taskfailures.setdefault(event.taskstring)
                 logger.error(str(event))
                 continue
 
@@ -942,11 +944,19 @@ def main(server, eventHandler, params, tf = TerminalFilter):
     try:
         termfilter.clearFooter()
         summary = ""
+        def print_hyperlink(url, link_text):
+            start = f'\033]8;;{url}\033\\'
+            end = '\033]8;;\033\\'
+            return f'{start}{link_text}{end}'
+
         if taskfailures:
             summary += pluralise("\nSummary: %s task failed:",
                                  "\nSummary: %s tasks failed:", len(taskfailures))
-            for failure in taskfailures:
+            for (failure, log_file) in taskfailures.items():
                 summary += "\n  %s" % failure
+                if log_file:
+                    hyperlink = print_hyperlink(f"file://{log_file}", log_file)
+                    summary += "\n    log: {}".format(hyperlink)
         if warnings:
             summary += pluralise("\nSummary: There was %s WARNING message.",
                                  "\nSummary: There were %s WARNING messages.", warnings)