Imported Upstream version 5.0.0.42

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external/corefx/Documentation/building/cross-platform-testing.md

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+# Running XUnit tests cross platform
+
+Unlike Windows, where we run tests as part of the build, we have a seperate
+explicit testing step on Linux and OSX. Over time, this special step will go
+away in favor of a similar "run tests during the build" model.
+
+`run-test.sh` is the shell script used by Jenkins in order to run all the XUnit
+tests cross platform. It combines the cross platform CoreCLR and CoreFX builds
+together into a test layout and then runs each test project from CoreFX.
+
+In order to run tests, you need to build a bunch of different projects. The
+instructions assume you are building for Linux, but are easily modifiable for OSX.
+
+1. Release or debug CoreCLR. In Jenkins we use a release CoreCLR build instead
+   of debug CoreCLR since it is much faster at actually running XUnit, but debug
+   will work if you have the time.
+
+   From the root of your CoreCLR enlistment on Linux, run `./build.sh Release` in
+   order to build.
+2. A corresponding version of mscorlib.dll. Depending on your platform, this may
+   be produced when you run  `build.sh`. Otherwise, this can be produced by
+   running `build.cmd linuxmscorlib Release` from a CoreCLR enlistment on
+   Windows. Remember that the runtime and mscorlib are tightly coupled with
+   respect to object sizes and layout so you need to ensure you have either a
+   release coreclr and release mscorlib or debug coreclr and debug mscorlib.
+3. A Linux build of CoreFX. We currently have experimental support for building
+   CoreFX on Linux via `build.sh`. 
+   The other option is:
+
+   * Build the managed parts of CoreFX on Windows. To do so run `build-managed.cmd -os=Linux`. It is okay to build a Debug version of CoreFX and run it
+   on top of a release CoreCLR (which is exactly what we do in Jenkins).
+
+   * Build the native parts of CoreFX on Linux. To do so run `./build-native.sh` from the root of your CoreFX enlistment.
+
+4. The packages folder which contains all the packages restored from NuGet and
+   MyGet when building CoreFX.
+
+
+After building all the projects, we need to copy any of the files we built on Windows
+over to our Linux machine. The easiest way to do this is to mount a windows
+share on linux. For example, I do:
+
+```
+# sudo mount.cifs "//MATELL3/D\$" ~/mnt/matell3/d -o user=matell
+```
+
+If needed, copy CoreFX:
+
+```
+# rsync -v -r ~/mnt/matell3/d/git/corefx/bin/tests ~/git/corefx/bin/tests
+```
+
+If needed, copy the packages folder:
+
+```
+# rsync -v -f ~/mnt/matell3/d/git/corefx/packages ~/git/corefx/packages
+```
+
+If needed, copy mscorlib:
+```
+# rsync -v -r  ~/mnt/matell3/d/git/coreclr/bin/Product/ ~/git/coreclr/bin/Product/
+```
+
+Then, run the tests. We need to pass an explict path to the location of CoreCLR
+and mscorlib.dll.
+
+```
+# ./run-test.sh --coreclr-bins ~/git/coreclr/bin/Product/Linux.x64.Release \
+--mscorlib-bins ~/git/coreclr/bin/Product/Linux.x64.Release \
+```
+
+run-test.sh should now invoke all the managed tests.