Fix loading of the Foundation framework under GNUstep

.travis.yml

@@ -1,7 +1,6 @@
 branches:
   only:
     - master
-os: osx
 matrix:
   include:
     # Note: The ordering of the environments is optimized so that the complete matrix runs as quickly as possible,
@@ -18,14 +17,32 @@ matrix:
     # With the following order, xcode6.4 will take up the first slot, and at the same time the three other
     # environments use the second slot in sequence. xcode9.2 will finish first and provide some early results - most
     # test failures happen in all environments and will be quickly reported this way.
+    # Linux builds have a higher limit than Mac builds, so the Linux environment will run in parallel with the Mac
+    # environments.
 
     # OSX 10.10 Yosemite
-    - osx_image: xcode6.4
+    - os: osx
+      osx_image: xcode6.4
     # macOS 10.12 Sierra
-    - osx_image: xcode9.2
-    - osx_image: xcode8.3
+    - os: osx
+      osx_image: xcode9.2
+    - os: osx
+      osx_image: xcode8.3
     # OSX 10.11 El Capitan
-    - osx_image: xcode7.3
+    - os: osx
+      osx_image: xcode7.3
+    # Linux with GNUstep
+    - os: linux
+      dist: xenial
+      addons:
+        apt:
+          packages:
+            - gnustep-devel
+    # Linux for flake8 only
+    - os: linux
+      dist: xenial
+      env:
+        - FLAKE8_ONLY=1
 language: generic
 cache:
   directories:
@@ -37,25 +54,40 @@ env:
     - PY36="3.6.5"
     - PY37="3.7.0"
 install:
-  # The different Travis environments have different pyenv versions, and not all have the Python versions we need,
-  # so we upgrade pyenv to get a consistent setup in all environments.
-  - brew update
-  - brew outdated pyenv || brew upgrade pyenv
+  - |
+    if [[ "${TRAVIS_OS_NAME}" == "osx" ]]; then
+      # The different Travis environments have different pyenv versions, and not all have the Python versions we need,
+      # so we upgrade pyenv to get a consistent setup in all environments.
+      brew update
+      brew outdated pyenv || brew upgrade pyenv
+    else
+      pushd "$(pyenv root)"
+      git checkout master
+      git pull
+      popd
+    fi
   # The existing pyenv shims from the build cache may no longer be valid, for example if pyenv was upgraded
   # (in which case the paths used in the shims point to an older, no longer installed pyenv version).
   # By rehashing the shims we can be sure that they are always valid again.
   - pyenv rehash
   # pyenv's shims directory is not in the PATH by default.
   - export PATH="$(pyenv root)/shims:${PATH}"
   # These are the Python versions that we want to test on.
-  - pyenv install --skip-existing ${PY34}
-  - pyenv install --skip-existing ${PY35}
-  - pyenv install --skip-existing ${PY36}
   - pyenv install --skip-existing ${PY37}
+  - pyenv install --skip-existing ${PY36}
+  - pyenv install --skip-existing ${PY35}
+  - pyenv install --skip-existing ${PY34}
   - pyenv global ${PY37} ${PY36} ${PY35} ${PY34} system
   # tox is not installed by default in some older Travis environments.
   - python3.6 -m pip install tox
-  - make -f Makefile
 script:
-  - export DYLD_LIBRARY_PATH=`pwd`/tests/objc
-  - python3.6 -m tox -e "py{34,35,36,37}-default,flake8"
+  - |
+    if [[ "${FLAKE8_ONLY}" == "1" ]]; then
+      python3.6 -m tox -e "flake8"
+    elif [[ "${TRAVIS_OS_NAME}" == "osx" ]]; then
+      make -f Makefile
+      DYLD_LIBRARY_PATH="$(pwd)/tests/objc" python3.6 -m tox -e "py{34,35,36,37}-default"
+    else
+      make -f Makefile
+      LD_LIBRARY_PATH="$(pwd)/tests/objc" python3.6 -m tox -e "py{34,35,36,37}-default"
+    fi

Makefile

@@ -1,17 +1,29 @@
 OBJ_FILES=tests/objc/Thing.o tests/objc/Example.o tests/objc/BaseExample.o tests/objc/Blocks.o
 
-# By default, build a universal i386/x86_64 binary.
-# Modify here (or on the command line) to build for other architecture(s).
-EXTRA_FLAGS=-arch i386 -arch x86_64
+OS := $(shell uname)
+CC = clang
+ifeq ($(OS),Darwin)
+	# By default, build a universal i386/x86_64 binary.
+	# Modify here (or on the command line) to build for other architecture(s).
+	CFLAGS = -arch i386 -arch x86_64
+	LDFLAGS = -dynamiclib -arch i386 -arch x86_64
+	LDLIBS = -fobjc-link-runtime
+	LIB_EXT = dylib
+else
+	CFLAGS = `gnustep-config --objc-flags`
+	LDFLAGS =
+	LDLIBS = `gnustep-config --objc-libs`
+	LIB_EXT = so
+endif
 
-all: tests/objc/librubiconharness.dylib
+all: tests/objc/librubiconharness.$(LIB_EXT)
 
-tests/objc/librubiconharness.dylib: $(OBJ_FILES)
-	clang -dynamiclib -fobjc-link-runtime $(EXTRA_FLAGS) $(OBJ_FILES) -o tests/objc/librubiconharness.dylib
+tests/objc/librubiconharness.$(LIB_EXT): $(OBJ_FILES)
+	$(CC) $(LDFLAGS) $(OBJ_FILES) -o tests/objc/librubiconharness.$(LIB_EXT) $(LDLIBS)
 
 clean:
-	rm -rf tests/objc/*.o tests/objc/*.d tests/objc/librubiconharness.dylib
+	rm -rf tests/objc/*.o tests/objc/*.d tests/objc/librubiconharness.$(LIB_EXT)
 
 %.o: %.m tests/objc/*.h
-	clang -x objective-c -I./tests/objc -c $(EXTRA_FLAGS) $< -o $@
+	$(CC) -c $(CFLAGS) $< -o $@
 

rubicon/objc/runtime.py

@@ -86,7 +86,13 @@ def load_library(name):
 
 libc = load_library('c')
 libobjc = load_library('objc')
-Foundation = load_library('Foundation')
+try:
+    Foundation = load_library('Foundation')
+except ValueError:
+    # The Foundation framework was not found. This means we're on a non-Apple system, so try to use GNUstep instead.
+    # Because GNUstep uses the traditional Unix library structure instead of frameworks, it provides the Foundation
+    # classes in a library called gnustep-base rather than Foundation.
+    Foundation = load_library('gnustep-base')
 
 
 @with_encoding(b'@')

tests/objc/Example.h

@@ -83,7 +83,7 @@ extern NSString *const SomeGlobalStringConstant;
 +(int) classAmbiguous;
 
 -(NSString *) toString;
--(NSString *) duplicateString:(NSString *) in;
+-(NSString *) duplicateString:(NSString *) inStr;
 -(NSString *) smiley;
 
 -(NSNumber *) theAnswer;

tests/objc/Example.m

@@ -169,9 +169,9 @@ -(NSString *) toString
     return [NSString stringWithFormat:@"This is an ObjC Example object"];
 }
 
--(NSString *) duplicateString:(NSString *) in
+-(NSString *) duplicateString:(NSString *) inStr
 {
-    return [NSString stringWithFormat:@"%@%@", in, in];
+    return [NSString stringWithFormat:@"%@%@", inStr, inStr];
 }
 
 -(NSString *) smiley