terminalwriter: extract plugin printing logic and add positive unittests

_pytest/terminal.py

@@ -298,18 +298,9 @@ class TerminalReporter:
 
         plugininfo = config.pluginmanager.list_plugin_distinfo()
         if plugininfo:
-            l = []
-            for plugin, dist in plugininfo:
-                # gets us name and version!
-                name = '{dist.project_name}-{dist.version}'.format(dist=dist)
-                # questionable convenience, but it keeps things short
-                if name.startswith("pytest-"):
-                    name = name[7:]
-                # we decided to print python package names
-                # they can have more than one plugin
-                if name not in l:
-                    l.append(name)
-            lines.append("plugins: %s" % ", ".join(l))
+
+            lines.append(
+                "plugins: %s" % ", ".join(_plugin_nameversions(plugininfo)))
         return lines
 
     def pytest_collection_finish(self, session):
@@ -554,3 +545,18 @@ def build_summary_stats_line(stats):
         color = 'yellow'
 
     return (line, color)
+
+
+def _plugin_nameversions(plugininfo):
+    l = []
+    for plugin, dist in plugininfo:
+        # gets us name and version!
+        name = '{dist.project_name}-{dist.version}'.format(dist=dist)
+        # questionable convenience, but it keeps things short
+        if name.startswith("pytest-"):
+            name = name[7:]
+        # we decided to print python package names
+        # they can have more than one plugin
+        if name not in l:
+            l.append(name)
+    return l

testing/test_terminal.py

@@ -1,19 +1,23 @@
 """
 terminal reporting of the full testing process.
 """
+import collections
 import pytest
 import py
 import pluggy
 import sys
 
 from _pytest.terminal import TerminalReporter, repr_pythonversion, getreportopt
-from _pytest.terminal import build_summary_stats_line
+from _pytest.terminal import build_summary_stats_line, _plugin_nameversions
 from _pytest import runner
 
 def basic_run_report(item):
     runner.call_and_report(item, "setup", log=False)
     return runner.call_and_report(item, "call", log=False)
 
+DistInfo = collections.namedtuple('DistInfo', ['project_name', 'version'])
+
+
 class Option:
     def __init__(self, verbose=False, fulltrace=False):
         self.verbose = verbose
@@ -40,6 +44,21 @@ def pytest_generate_tests(metafunc):
                          funcargs={'option': Option(fulltrace=True)})
 
 
+@pytest.mark.parametrize('input,expected', [
+    ([DistInfo(project_name='test', version=1)], ['test-1']),
+    ([DistInfo(project_name='pytest-test', version=1)], ['test-1']),
+    ([
+        DistInfo(project_name='test', version=1),
+        DistInfo(project_name='test', version=1)
+    ], ['test-1']),
+], ids=['normal', 'prefix-strip', 'deduplicate'])
+
+def test_plugin_nameversion(input, expected):
+    pluginlist = [(None, x) for x in input]
+    result = _plugin_nameversions(pluginlist)
+    assert result == expected
+
+
 class TestTerminal:
     def test_pass_skip_fail(self, testdir, option):
         testdir.makepyfile("""
@@ -783,4 +802,3 @@ def test_summary_stats(exp_line, exp_color, stats_arg):
     print("Actually got:   \"%s\"; with color \"%s\"" % (line, color))
     assert line == exp_line
     assert color == exp_color
-