From 3990333f3d5d888df8f713b79812d5aa1a74bb17 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ciro=20Santilli=20=E5=85=AD=E5=9B=9B=E4=BA=8B=E4=BB=B6=20?=
 =?UTF-8?q?=E6=B3=95=E8=BD=AE=E5=8A=9F?= <ciro.santilli@gmail.com>
Date: Tue, 20 Oct 2020 01:00:00 +0000
Subject: [PATCH] python relative import

---
 README.adoc                                   | 15 ++++++++++++++
 .../lkmc/python/relative_import/README.adoc   |  1 +
 .../lkmc/python/relative_import/__init__.py   |  0
 .../python/relative_import/mydir/__init__.py  |  0
 .../relative_import/mydir/myfile_user.py      |  7 +++++++
 .../lkmc/python/relative_import/myfile.py     |  1 +
 .../python/relative_import/myfile_user.py     |  7 +++++++
 .../lkmc/python/relative_import/test          | 20 +++++++++++++++++++
 8 files changed, 51 insertions(+)
 create mode 100644 rootfs_overlay/lkmc/python/relative_import/README.adoc
 create mode 100644 rootfs_overlay/lkmc/python/relative_import/__init__.py
 create mode 100644 rootfs_overlay/lkmc/python/relative_import/mydir/__init__.py
 create mode 100755 rootfs_overlay/lkmc/python/relative_import/mydir/myfile_user.py
 create mode 100644 rootfs_overlay/lkmc/python/relative_import/myfile.py
 create mode 100755 rootfs_overlay/lkmc/python/relative_import/myfile_user.py
 create mode 100755 rootfs_overlay/lkmc/python/relative_import/test

diff --git a/README.adoc b/README.adoc
index 071748a..cf183d8 100644
--- a/README.adoc
+++ b/README.adoc
@@ -18506,6 +18506,8 @@ The only `Impl` used appears to be `O3CPUImpl`? This is explicitly instantiated
 template class O3ThreadContext<O3CPUImpl>;
 ....
 
+see also: https://stackoverflow.com/questions/64420547/in-gem5-how-do-i-know-the-specific-location-of-the-class/64423633#64423633
+
 Unlike in `SimpleThread` however, `O3ThreadContext` does not contain the register data itself, e.g. `O3ThreadContext::readIntRegFlat` instead forwards to `cpu`:
 
 ....
@@ -20912,6 +20914,19 @@ link:rootfs_overlay/lkmc/python/unittest_find/[] contains examples to test how t
 * https://stackoverflow.com/questions/1732438/how-do-i-run-all-python-unit-tests-in-a-directory
 * https://stackoverflow.com/questions/46976256/recursive-unittest-discovery-with-python3-and-without-init-py-files
 
+====== Python relative imports
+
+link:rootfs_overlay/lkmc/python/relative_import/[] contains examples to test how how to do relative imports in Python.
+
+This subject is impossible to understand.
+
+Related questions:
+
+* https://stackoverflow.com/questions/16981921/relative-imports-in-python-3
+* https://stackoverflow.com/questions/14132789/relative-imports-for-the-billionth-time
+* https://stackoverflow.com/questions/21490860/relative-imports-with-unittest-in-python
+* https://stackoverflow.com/questions/714063/importing-modules-from-parent-folder
+
 ===== Build and install the interpreter
 
 Buildroot has a Python package that can be added to the guest image:
diff --git a/rootfs_overlay/lkmc/python/relative_import/README.adoc b/rootfs_overlay/lkmc/python/relative_import/README.adoc
new file mode 100644
index 0000000..825f1f2
--- /dev/null
+++ b/rootfs_overlay/lkmc/python/relative_import/README.adoc
@@ -0,0 +1 @@
+https://cirosantilli.com/linux-kernel-module-cheat#python-relative-imports
diff --git a/rootfs_overlay/lkmc/python/relative_import/__init__.py b/rootfs_overlay/lkmc/python/relative_import/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/rootfs_overlay/lkmc/python/relative_import/mydir/__init__.py b/rootfs_overlay/lkmc/python/relative_import/mydir/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/rootfs_overlay/lkmc/python/relative_import/mydir/myfile_user.py b/rootfs_overlay/lkmc/python/relative_import/mydir/myfile_user.py
new file mode 100755
index 0000000..75755b3
--- /dev/null
+++ b/rootfs_overlay/lkmc/python/relative_import/mydir/myfile_user.py
@@ -0,0 +1,7 @@
+#!/usr/bin/env python
+
+import myfile
+
+assert myfile.a == 1
+
+b = myfile.a + 1
diff --git a/rootfs_overlay/lkmc/python/relative_import/myfile.py b/rootfs_overlay/lkmc/python/relative_import/myfile.py
new file mode 100644
index 0000000..1337a53
--- /dev/null
+++ b/rootfs_overlay/lkmc/python/relative_import/myfile.py
@@ -0,0 +1 @@
+a = 1
diff --git a/rootfs_overlay/lkmc/python/relative_import/myfile_user.py b/rootfs_overlay/lkmc/python/relative_import/myfile_user.py
new file mode 100755
index 0000000..1042dab
--- /dev/null
+++ b/rootfs_overlay/lkmc/python/relative_import/myfile_user.py
@@ -0,0 +1,7 @@
+#!/usr/bin/env python
+
+import myfile
+import mydir.myfile_user
+
+assert myfile.a == 1
+assert mydir.myfile_user.b == 2
diff --git a/rootfs_overlay/lkmc/python/relative_import/test b/rootfs_overlay/lkmc/python/relative_import/test
new file mode 100755
index 0000000..b63d1ba
--- /dev/null
+++ b/rootfs_overlay/lkmc/python/relative_import/test
@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+set -eux
+
+# myfile_user works from all directories.
+./myfile_user.py
+cd ..
+relative_import/myfile_user.py
+cd relative_import/mydir
+../myfile_user.py
+cd ..
+
+# TODO any better way to run mydir/myfile_user.py?
+
+# ./mydir/myfile_user.py
+#Traceback (most recent call last):
+#  File "./mydir/myfile_user.py", line 3, in <module>
+#    import myfile
+#ModuleNotFoundError: No module named 'myfile'
+
+python -m mydir.myfile_user