Clear error if importing module with same name as built-in module.

pekkaklarck · pekkaklarck · commit 56402aaf9fdc · 2017-02-13T00:11:22.000+02:00
Fixes robotframework#2541.
diff --git a/atest/robot/test_libraries/library_import_failing.robot b/atest/robot/test_libraries/library_import_failing.robot
@@ -1,5 +1,5 @@
 *** Settings ***
-Suite Setup     Run Tests  ${EMPTY}  test_libraries/library_import_failing.robot
+Suite Setup     Run Tests    ${EMPTY}    test_libraries/library_import_failing.robot
 Resource        atest_resource.robot
 
 *** Test Cases ***
@@ -53,3 +53,6 @@ Initializing Java Library Fails
     Import Should Have Failed    9    test_libraries/library_import_failing.robot
     ...  Initializing test library 'InitializationFailJavaLibrary' with no arguments failed: Initialization failed!
     ...  stacktrace=at InitializationFailJavaLibrary.<init>(InitializationFailJavaLibrary.java:4)
+
+Importing library with same name as Python built-in module
+    Check Test Case    Name clash with Python builtin-module
diff --git a/atest/testdata/test_libraries/library_import_failing.robot b/atest/testdata/test_libraries/library_import_failing.robot
@@ -9,7 +9,16 @@ Library         ${non existing nön äscii}
 Library         InitializationFailLibrary.py    ${nön existing}    ${vars here}
 Library         # Missing name causes error
 Library         InitializationFailJavaLibrary.java
+Library         OperatingSystem    # This succeeds after all failed imports
+
+*** Variables ***
+${CLASH WITH BUILTIN}    %{TEMPDIR}${/}sys.py
 
 *** Test Cases ***
-Dummy test
-    Comment    Only testing imports here
+Name clash with Python builtin-module
+    [Documentation]    FAIL
+    ...    Importing test library '${CLASH WITH BUILTIN}' failed:\
+    ...    Cannot import custom module with same name as Python built-in module.
+    Create File    ${CLASH WITH BUILTIN}    def kw(): pass
+    Import library    ${CLASH WITH BUILTIN}
+    [Teardown]    Remove File    ${CLASH WITH BUILTIN}
diff --git a/src/robot/utils/importer.py b/src/robot/utils/importer.py
@@ -144,6 +144,9 @@ def __init__(self, logger):
         self._logger = logger
 
     def _import(self, name, fromlist=None, retry=True):
+        if name in sys.builtin_module_names:
+            raise DataError('Cannot import custom module with same name as '
+                            'Python built-in module.')
         invalidate_import_caches()
         try:
             try:
