improve mitmproxy.scripts semantics, clean up tests

mitmproxy/console/__init__.py

@@ -318,6 +318,7 @@ class ConsoleMaster(flow.FlowMaster):
 
         try:
             s = script.Script(command, script.ScriptContext(self))
+            s.load()
         except script.ScriptException as v:
             signals.status_message.send(
                 message = "Error loading script."

mitmproxy/flow.py

@@ -685,6 +685,7 @@ class FlowMaster(controller.Master):
         """
         try:
             s = script.Script(command, script.ScriptContext(self))
+            s.load()
         except script.ScriptException as v:
             return v.args[0]
         if use_reloader:

mitmproxy/script/script.py

@@ -22,7 +22,15 @@ class Script(object):
         self.args = self.parse_command(command)
         self.ctx = context
         self.ns = None
+
+    def __enter__(self):
         self.load()
+        return self
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        if exc_val:
+            return False  # reraise the exception
+        self.unload()
 
     @property
     def filename(self):
@@ -35,7 +43,7 @@ class Script(object):
         if os.name == "nt":  # Windows: escape all backslashes in the path.
             backslashes = shlex.split(command, posix=False)[0].count("\\")
             command = command.replace("\\", "\\\\", backslashes)
-        args = shlex.split(command)
+        args = shlex.split(command)  # pragma: nocover
         args[0] = os.path.expanduser(args[0])
         if not os.path.exists(args[0]):
             raise ScriptException(
@@ -58,7 +66,7 @@ class Script(object):
                 ScriptException on failure
         """
         if self.ns is not None:
-            self.unload()
+            raise ScriptException("Script is already loaded")
         script_dir = os.path.dirname(os.path.abspath(self.args[0]))
         self.ns = {'__file__': os.path.abspath(self.args[0])}
         sys.path.append(script_dir)

test/mitmproxy/script/test_script.py

@@ -0,0 +1,83 @@
+from mitmproxy.script import Script
+from mitmproxy.exceptions import ScriptException
+from test.mitmproxy import tutils
+
+
+class TestParseCommand:
+    def test_empty_command(self):
+        with tutils.raises(ScriptException):
+            Script.parse_command("")
+
+        with tutils.raises(ScriptException):
+            Script.parse_command("  ")
+
+    def test_no_script_file(self):
+        with tutils.raises("not found"):
+            Script.parse_command("notfound")
+
+        with tutils.tmpdir() as dir:
+            with tutils.raises("not a file"):
+                Script.parse_command(dir)
+
+    def test_parse_args(self):
+        with tutils.chdir(tutils.test_data.dirname):
+            assert Script.parse_command("scripts/a.py") == ["scripts/a.py"]
+            assert Script.parse_command("scripts/a.py foo bar") == ["scripts/a.py", "foo", "bar"]
+            assert Script.parse_command("scripts/a.py 'foo bar'") == ["scripts/a.py", "foo bar"]
+
+    @tutils.skip_not_windows
+    def test_parse_windows(self):
+        with tutils.chdir(tutils.test_data.dirname):
+            assert Script.parse_command("scripts\\a.py") == ["scripts\\a.py"]
+            assert Script.parse_command("scripts\\a.py 'foo \\ bar'") == ["scripts\\a.py", 'foo \\ bar']
+
+
+def test_simple():
+    with tutils.chdir(tutils.test_data.path("scripts")):
+        s = Script("a.py --var 42", None)
+        assert s.filename == "a.py"
+        assert s.ns is None
+
+        s.load()
+        assert s.ns["var"] == 42
+
+        s.run("here")
+        assert s.ns["var"] == 43
+
+        s.unload()
+        assert s.ns is None
+
+        with tutils.raises(ScriptException):
+            s.run("here")
+
+        with Script("a.py --var 42", None) as s:
+            s.run("here")
+
+
+def test_script_exception():
+    with tutils.chdir(tutils.test_data.path("scripts")):
+        s = Script("syntaxerr.py", None)
+        with tutils.raises(ScriptException):
+            s.load()
+
+        s = Script("starterr.py", None)
+        with tutils.raises(ScriptException):
+            s.load()
+
+        s = Script("a.py", None)
+        s.load()
+        with tutils.raises(ScriptException):
+            s.load()
+
+        s = Script("a.py", None)
+        with tutils.raises(ScriptException):
+            s.run("here")
+
+        with tutils.raises(ScriptException):
+            with Script("reqerr.py", None) as s:
+                s.run("request", None)
+
+        s = Script("unloaderr.py", None)
+        s.load()
+        with tutils.raises(ScriptException):
+            s.unload()

test/mitmproxy/test_examples.py

@@ -31,9 +31,8 @@ class DummyContext(object):
 def example(command):
     command = os.path.join(example_dir, command)
     ctx = DummyContext()
-    s = script.Script(command, ctx)
+    with script.Script(command, ctx) as s:
         yield s
-    s.unload()
 
 
 def test_load_scripts():
@@ -52,8 +51,10 @@ def test_load_scripts():
             f += " ~a"
         if "modify_response_body" in f:
             f += " foo bar"  # two arguments required
+
+        s = script.Script(f, script.ScriptContext(tmaster))
         try:
-            s = script.Script(f, script.ScriptContext(tmaster))  # Loads the script file.
+            s.load()
         except Exception as v:
             if "ImportError" not in str(v):
                 raise

test/mitmproxy/test_script.py

@@ -1,27 +1,9 @@
-import os
 import time
 import mock
 from mitmproxy import script, flow
 from . import tutils
 
 
-def test_simple():
-    s = flow.State()
-    fm = flow.FlowMaster(None, s)
-    sp = tutils.test_data.path("scripts/a.py")
-    p = script.Script("%s --var 40" % sp, script.ScriptContext(fm))
-
-    assert "here" in p.ns
-    assert p.run("here") == 41
-    assert p.run("here") == 42
-
-    tutils.raises(script.ScriptException, p.run, "errargs")
-
-    # Check reload
-    p.load()
-    assert p.run("here") == 41
-
-
 def test_duplicate_flow():
     s = flow.State()
     fm = flow.FlowMaster(None, s)
@@ -33,35 +15,6 @@ def test_duplicate_flow():
     assert fm.state.view[1].request.is_replay
 
 
-def test_err():
-    s = flow.State()
-    fm = flow.FlowMaster(None, s)
-    sc = script.ScriptContext(fm)
-
-    tutils.raises(
-        "not found",
-        script.Script, "nonexistent", sc
-    )
-
-    tutils.raises(
-        "not a file",
-        script.Script, tutils.test_data.path("scripts"), sc
-    )
-
-    tutils.raises(
-        script.ScriptException,
-        script.Script, tutils.test_data.path("scripts/syntaxerr.py"), sc
-    )
-
-    tutils.raises(
-        script.ScriptException,
-        script.Script, tutils.test_data.path("scripts/loaderr.py"), sc
-    )
-
-    scr = script.Script(tutils.test_data.path("scripts/unloaderr.py"), sc)
-    tutils.raises(script.ScriptException, scr.unload)
-
-
 @tutils.skip_appveyor
 def test_concurrent():
     s = flow.State()
@@ -117,16 +70,6 @@ def test_concurrent2():
 def test_concurrent_err():
     s = flow.State()
     fm = flow.FlowMaster(None, s)
-    tutils.raises(
-        "Concurrent decorator not supported for 'start' method",
-        script.Script,
-        tutils.test_data.path("scripts/concurrent_decorator_err.py"),
-        fm)
-
-
-def test_command_parsing():
-    s = flow.State()
-    fm = flow.FlowMaster(None, s)
-    absfilepath = os.path.normcase(tutils.test_data.path("scripts/a.py"))
-    s = script.Script(absfilepath, script.ScriptContext(fm))
-    assert os.path.isfile(s.args[0])
+    with tutils.raises("Concurrent decorator not supported for 'start' method"):
+        s = script.Script(tutils.test_data.path("scripts/concurrent_decorator_err.py"), fm)
+        s.load()

test/mitmproxy/tutils.py

@@ -26,6 +26,13 @@ def skip_windows(fn):
         return fn
 
 
+def skip_not_windows(fn):
+    if os.name == "nt":
+        return fn
+    else:
+        return _skip_windows
+
+
 def _skip_appveyor(*args):
     raise SkipTest("Skipped on AppVeyor.")
 
@@ -119,15 +126,18 @@ def get_body_line(last_displayed_body, line_nb):
     return last_displayed_body.contents()[line_nb + 2]
 
 
+@contextmanager
+def chdir(dir):
+    orig_dir = os.getcwd()
+    os.chdir(dir)
+    yield
+    os.chdir(orig_dir)
+
 @contextmanager
 def tmpdir(*args, **kwargs):
-    orig_workdir = os.getcwd()
     temp_workdir = tempfile.mkdtemp(*args, **kwargs)
-    os.chdir(temp_workdir)
-
+    with chdir(temp_workdir):
         yield temp_workdir
-
-    os.chdir(orig_workdir)
     shutil.rmtree(temp_workdir)