main: show an error for job on empty / new DB

Instead of printing some ugly IndexError backtrace when running `job` on a fresh
install, just print an error message and exit with non-zero exit code.

For `job -g <arg>` it was failing to iterate None from db getActive, so return []
instead.

jobrunner/db/__init__.py

@@ -146,9 +146,9 @@ def recentGet(self):
             try:
                 return json.loads(self.db[self.RECENT])
             except json.JSONDecodeError:
-                return None
+                return []
         else:
-            return None
+            return []
 
     def recentSet(self, key):
         recent = self.recent
@@ -462,7 +462,8 @@ def filterJobsWith(job, startTime=True, skipReminders=False):
         return True
 
     def getJobMatch(self, key, thisWs, skipReminders=False):
-        # pylint: disable=too-many-return-statements,too-many-branches
+        # pylint: disable=too-many-return-statements,too-many-branches,
+        # pylint: disable=too-many-statements
         if key == '.':
             lastJob = self.active.lastJob
             if lastJob:

jobrunner/main.py

@@ -114,7 +114,12 @@ def impl_main(args=None):
     elif options.wait:
         pass
     else:
-        sprint(jobs.getLog(key=None, thisWs=options.tw, skipReminders=True))
+        try:
+            sprint(jobs.getLog(key=None, thisWs=options.tw, skipReminders=True))
+        except NoMatchingJobError as error:
+            jobs.unlock()
+            sprint("Error:", error)
+            sys.exit(1)
         jobs.unlock()
         sys.exit(0)
 
@@ -235,7 +240,7 @@ def main(args=None):
     try:
         impl_main(args=args)
     except NoMatchingJobError as error:
-        print(error)
+        sprint("Error:", error)
         sys.exit(1)
 
 
@@ -730,7 +735,7 @@ def maybeHandle(options, jobs, handler):
             sys.exit(0)
     except NoMatchingJobError as error:
         jobs.unlock()
-        print("Error:", error)
+        sprint("Error:", error)
         sys.exit(1)
     except ExitCode as exitCode:
         jobs.unlock()

jobrunner/test/integration/integration_lib.py

@@ -77,7 +77,8 @@ def run(cmd, capture=False, env=None):
             return check_call(cmd, env=env)
     except CalledProcessError as error:
         print(error.output)
-        LOG.debug("cmd %r => ERROR %s", cmd, autoDecode(error.output).strip())
+        errOut = autoDecode(error.output) if error.output else "n/a"
+        LOG.debug("cmd %r => ERROR %s", cmd, errOut.strip())
         raise
 
 

jobrunner/test/integration/smoke_test.py

@@ -9,6 +9,7 @@
 from unittest import TestCase
 
 from pexpect import EOF
+import pytest
 import simplejson as json
 import six
 
@@ -60,6 +61,20 @@ def testUnicodeSmoke2():
         unicodeCase()
 
 
+@pytest.mark.parametrize("cmd,expected", [
+    (['job'], r"^Error: Job database is empty$"),
+    (['job', '-g', '.'], r"^Error: No job for key .\..$"),
+    (['job', '-g', 'xxx'], r"^Error: No job for key .xxx.$"),
+])
+def testEmptyDb(cmd, expected):
+    with testEnv():
+        with pytest.raises(CalledProcessError) as error:
+            run(cmd, capture=True)
+        output = autoDecode(error.value.output)
+        print(output)
+        assert re.match(expected, output)
+
+
 class SmokeTest(TestCase):
     def testBasic(self):
         with testEnv() as env: