<rdar://problem/11109316>

command script import now does reloads - for real
If you invoke command script import foo and it detects that foo has already been imported, it will
 - invoke reload(foo) to reload the module in Python
 - re-invoke foo.__lldb_init_module
 This second step is necessary to ensure that LLDB does not keep cached copies of any formatter, command, ... that the module is providing

Usual caveats with Python imports persist. Among these:
 - if you have objects lurking around, reloading the module won't magically update them to reflect changes
 - if module A imports module B, reloading A won't reload B
These are Python-specific issues independent of LLDB that would require more extensive design work

The --allow-reload (-r) option is maintained for compatibility with existing scripts, but is clearly documented as redundant - reloading is always enabled whether you use it or not

llvm-svn: 182977

4 files changed, 10 insertions, 9 deletions

diff --git a/lldb/source/Commands/CommandObjectCommands.cpp b/lldb/source/Commands/CommandObjectCommands.cpp
index 278fdc0c876..5964eacce55 100644
--- a/lldb/source/Commands/CommandObjectCommands.cpp
+++ b/lldb/source/Commands/CommandObjectCommands.cpp
@@ -1355,7 +1355,7 @@ protected:
         void
         OptionParsingStarting ()
         {
-            m_allow_reload = false;
+            m_allow_reload = true;
         }
         
         const OptionDefinition*
@@ -1426,7 +1426,7 @@ protected:
 OptionDefinition
 CommandObjectCommandsScriptImport::CommandOptions::g_option_table[] =
 {
-    { LLDB_OPT_SET_1, false, "allow-reload", 'r', no_argument, NULL, 0, eArgTypeNone,        "Allow the script to be loaded even if it was already loaded before (for Python, the __lldb_init_module function will be called again, but the module will not be reloaded from disk)."},
+    { LLDB_OPT_SET_1, false, "allow-reload", 'r', no_argument, NULL, 0, eArgTypeNone,        "Allow the script to be loaded even if it was already loaded before. This argument exists for backwards compatibility, but reloading is always allowed, whether you specify it or not."},
     { 0, false, NULL, 0, 0, NULL, 0, eArgTypeNone, NULL }
 };
 
diff --git a/lldb/source/Core/Module.cpp b/lldb/source/Core/Module.cpp
index 0967ef7100d..d8420ab8af1 100644
--- a/lldb/source/Core/Module.cpp
+++ b/lldb/source/Core/Module.cpp
@@ -1287,7 +1287,7 @@ Module::LoadScriptingResourceInTarget (Target *target, Error& error, Stream* fee
                         }
                         StreamString scripting_stream;
                         scripting_fspec.Dump(&scripting_stream);
-                        const bool can_reload = false;
+                        const bool can_reload = true;
                         const bool init_lldb_globals = false;
                         bool did_load = script_interpreter->LoadScriptingModule(scripting_stream.GetData(), can_reload, init_lldb_globals, error);
                         if (!did_load)
diff --git a/lldb/source/Interpreter/ScriptInterpreterPython.cpp b/lldb/source/Interpreter/ScriptInterpreterPython.cpp
index b54ef1ca901..da80e0ce0e8 100644
--- a/lldb/source/Interpreter/ScriptInterpreterPython.cpp
+++ b/lldb/source/Interpreter/ScriptInterpreterPython.cpp
@@ -2672,7 +2672,10 @@ ScriptInterpreterPython::LoadScriptingModule (const char* pathname,
 
         // now actually do the import
         command_stream.Clear();
-        command_stream.Printf("import %s",basename.c_str());
+        if (was_imported)
+            command_stream.Printf("reload(%s)",basename.c_str());
+        else
+            command_stream.Printf("import %s",basename.c_str());
         bool import_retval = ExecuteMultipleLines(command_stream.GetData(), ScriptInterpreter::ExecuteScriptOptions().SetEnableIO(false).SetSetLLDBGlobals(false).SetMaskoutErrors(false));
         PyObject* py_error = PyErr_Occurred(); // per Python docs: "you do not need to Py_DECREF()" the return of this function
         
diff --git a/lldb/test/functionalities/command_script/import/TestImport.py b/lldb/test/functionalities/command_script/import/TestImport.py
index 2356fcee850..2f0121bd73d 100644
--- a/lldb/test/functionalities/command_script/import/TestImport.py
+++ b/lldb/test/functionalities/command_script/import/TestImport.py
@@ -45,17 +45,15 @@ class ImportTestCase(TestBase):
                 error=True, startstr='error: module importing failed')
         self.expect("command script import ./nosuchfolder/",
                 error=True, startstr='error: module importing failed')
-        self.expect("command script import ./foo/foo.py",
-                error=True, startstr='error: module importing failed')
+        self.expect("command script import ./foo/foo.py", error=False)
 
         self.runCmd("command script import --allow-reload ./thepackage")
         self.expect("TPcommandA",substrs=["hello world A"])
         self.expect("TPcommandB",substrs=["hello world B"])
 
         self.runCmd("script import dummymodule")
-        self.expect("command script import ./dummymodule.py",
-                error=True, startstr='error: module importing failed')
-        self.runCmd("command script import --allow-reload ./dummymodule.py")
+        self.expect("command script import ./dummymodule.py", error=False)
+        self.expect("command script import --allow-reload ./dummymodule.py", error=False)
 
         self.runCmd("command script add -f foo.foo_function foocmd")
         self.runCmd("command script add -f foobar.foo_function foobarcmd")