level three verbosity shows packaging output (#1048)

Resolves #1047.

5 files changed, 46 insertions, 5 deletions

diff --git a/docs/changelog/1042.bugfix.rst b/docs/changelog/1042.bugfix.rst
index 53bde7e2..14d27749 100644
--- a/docs/changelog/1042.bugfix.rst
+++ b/docs/changelog/1042.bugfix.rst
@@ -1,4 +1,4 @@
 session packages are now put inside a numbered directory (instead of prefix numbering it,
 because pip fails when wheels are not named according to
 `PEP-491 <https://www.python.org/dev/peps/pep-0491/#id9>`_, and prefix numbering messes with this)
-- by user:`gaborbernat`
+- by :user:`gaborbernat`
diff --git a/docs/changelog/1047.feature.rst b/docs/changelog/1047.feature.rst
new file mode 100644
index 00000000..074a3574
--- /dev/null
+++ b/docs/changelog/1047.feature.rst
@@ -0,0 +1 @@
+level three verbosity (``-vvv``) show the packaging output - by :user:`gaborbernat`
diff --git a/src/tox/package.py b/src/tox/package.py
index 45c88829..e75a9f18 100644
--- a/src/tox/package.py
+++ b/src/tox/package.py
@@ -143,10 +143,12 @@ def make_sdist_legacy(report, config, session):
     with session.newaction(None, "packaging") as action:
         action.setactivity("sdist-make", setup)
         session.make_emptydir(config.distdir)
-        action.popen(
+        build_log = action.popen(
             [sys.executable, setup, "sdist", "--formats=zip", "--dist-dir", config.distdir],
             cwd=config.setupdir,
+            returnout=True,
         )
+        report.verbosity2(build_log)
         try:
             return config.distdir.listdir()[0]
         except py.error.ENOENT:
@@ -195,7 +197,7 @@ def build_isolated(config, report, session):
         ) as action:
             package_venv.run_install_command(packages=build_requires_dep, action=action)
         session.finishvenv(package_venv)
-    return perform_isolated_build(build_info, package_venv, session, config)
+    return perform_isolated_build(build_info, package_venv, session, config, report)
 
 
 def get_build_info(folder, report):
@@ -238,7 +240,7 @@ def get_build_info(folder, report):
     return BuildInfo(requires, module, "{}{}".format(module, obj))
 
 
-def perform_isolated_build(build_info, package_venv, session, config):
+def perform_isolated_build(build_info, package_venv, session, config, report):
     with session.newaction(
         package_venv, "perform-isolated-build", package_venv.envconfig.envdir
     ) as action:
@@ -263,6 +265,7 @@ def perform_isolated_build(build_info, package_venv, session, config):
             action=action,
             cwd=session.config.setupdir,
         )
+        report.verbosity2(result)
         return config.distdir.join(result.split("\n")[-2])
 
 
diff --git a/src/tox/venv.py b/src/tox/venv.py
index 12cd44cd..29d5b644 100755
--- a/src/tox/venv.py
+++ b/src/tox/venv.py
@@ -91,7 +91,7 @@ class CreationConfig:
         if self_deps != other_deps:
             if deps_matches_subset:
                 diff = other_deps - self_deps
-                if not diff:
+                if diff:
                     return False, "missing in previous {!r}".format(diff)
             else:
                 return False, "{!r}!={!r}".format(self_deps, other_deps)
diff --git a/tests/unit/test_package.py b/tests/unit/test_package.py
index 46014b5b..9c117eb4 100644
--- a/tests/unit/test_package.py
+++ b/tests/unit/test_package.py
@@ -404,3 +404,40 @@ def test_install_via_installpkg(mock_venv, initproj, cmd):
     fake_package = base.ensure(".tox", "dist", "pkg123-0.1.zip")
     result = cmd("-e", "py", "--notest", "--installpkg", str(fake_package.relto(base)))
     assert result.ret == 0, result.out
+
+
+def test_verbose_isolated_build(initproj, mock_venv, cmd):
+    initproj(
+        "example123-0.5",
+        filedefs={
+            "tox.ini": """
+                    [tox]
+                    isolated_build = true
+                    """,
+            "pyproject.toml": """
+                    [build-system]
+                    requires = ["setuptools >= 35.0.2"]
+                    build-backend = 'setuptools.build_meta'
+                                """,
+        },
+    )
+    result = cmd("--sdistonly", "-vvv")
+    assert "running sdist" in result.out, result.out
+    assert "running egg_info" in result.out, result.out
+    assert "Writing example123-0.5{}setup.cfg".format(os.sep) in result.out, result.out
+
+
+def test_verbose_legacy_build(initproj, mock_venv, cmd):
+    initproj(
+        "example123-0.5",
+        filedefs={
+            "tox.ini": """
+                    [tox]
+                    isolated_build = false
+                    """
+        },
+    )
+    result = cmd("--sdistonly", "-vvv")
+    assert "running sdist" in result.out, result.out
+    assert "running egg_info" in result.out, result.out
+    assert "Writing example123-0.5{}setup.cfg".format(os.sep) in result.out, result.out