ENH: Explain rebuilds

tests/test_environment.py

@@ -7,6 +7,8 @@
     :copyright: Copyright 2007-2019 by the Sphinx team, see AUTHORS.
     :license: BSD, see LICENSE for details.
 """
+import os
+import shutil
 import pytest
 
 from sphinx.builders.html import StandaloneHTMLBuilder
@@ -23,18 +25,30 @@ def test_config_status(make_app, app_params):
     app1 = make_app(*args, freshenv=True, **kwargs)
     assert app1.env.config_status == CONFIG_NEW
     app1.build()
+    assert '[new config] 1 added' in app1._status.getvalue()
 
     # incremental build (no config changed)
     app2 = make_app(*args, **kwargs)
     assert app2.env.config_status == CONFIG_OK
+    app2.build()
+    assert "0 added, 0 changed, 0 removed" in app2._status.getvalue()
 
     # incremental build (config entry changed)
-    app3 = make_app(*args, confoverrides={'master_doc': 'content'}, **kwargs)
+    app3 = make_app(*args, confoverrides={'master_doc': 'indexx'}, **kwargs)
+    fname = os.path.join(app3.srcdir, 'index.rst')
+    assert os.path.isfile(fname)
+    shutil.move(fname, fname[:-4] + 'x.rst')
     assert app3.env.config_status == CONFIG_CHANGED
+    app3.build()
+    shutil.move(fname[:-4] + 'x.rst', fname)
+    assert "[config changed ('master_doc')] 1 added" in app3._status.getvalue()
 
     # incremental build (extension changed)
     app4 = make_app(*args, confoverrides={'extensions': ['sphinx.ext.autodoc']}, **kwargs)
     assert app4.env.config_status == CONFIG_EXTENSIONS_CHANGED
+    app4.build()
+    want_str = "[extensions changed ('sphinx.ext.autodoc')] 1 added"
+    assert want_str in app4._status.getvalue()
 
 
 @pytest.mark.sphinx('dummy')