Add test_pywasmcross.py

.circleci/config.yml

@@ -73,10 +73,14 @@ jobs:
     <<: *defaults
     steps:
       - checkout
+      - run:
+          name: deps
+          command: |
+            sudo pip install pytest-cov
       - run:
           name: test
           command: |
-            pytest test -v -k 'not (chrome or firefox)'
+            pytest test -v -k 'not (chrome or firefox)' --cov=pyodide_build --cov=pyodide
 
   benchmark:
     <<: *defaults

pyodide_build/pywasmcross.py

@@ -105,7 +105,7 @@ def capture_compile(args):
         sys.exit(result.returncode)
 
 
-def handle_command(line, args):
+def handle_command(line, args, pretend=False):
     # This is a special case to skip the compilation tests in numpy that aren't
     # actually part of the build
     for arg in line:
@@ -156,9 +156,10 @@ def handle_command(line, args):
 
     print(' '.join(new_args))
 
-    result = subprocess.run(new_args)
-    if result.returncode != 0:
-        sys.exit(result.returncode)
+    if not pretend:
+        result = subprocess.run(new_args)
+        if result.returncode != 0:
+            sys.exit(result.returncode)
 
     # Emscripten .so files shouldn't have the native platform slug
     if shared:
@@ -169,7 +170,9 @@ def handle_command(line, args):
             if renamed.endswith(ext):
                 renamed = renamed[:-len(ext)] + '.so'
                 break
-        os.rename(output, renamed)
+        if not pretend:
+            os.rename(output, renamed)
+    return new_args
 
 
 def replay_compile(args):

test/pyodide_build/test_pywasmcross.py

+from collections import namedtuple
+from pathlib import Path
+import sys
+
+sys.path.append(str(Path(__file__).parents[2]))
+
+from pyodide_build.pywasmcross import handle_command  # noqa: E402
+
+
+def _args_wrapper(func):
+    """Convert function to take as input / return a string instead of a
+    list of arguments
+
+    Also sets pretend=True
+    """
+    def _inner(line, *pargs):
+        args = line.split()
+        res = func(args, *pargs, pretend=True)
+        if hasattr(res, '__len__'):
+            return ' '.join(res)
+        else:
+            return res
+    return _inner
+
+
+handle_command_wrap = _args_wrapper(handle_command)
+# TODO: add f2c here
+
+
+def test_handle_command():
+    Args = namedtuple('args', ['cflags', 'ldflags'])
+    args = Args(cflags='', ldflags='')
+    assert handle_command_wrap('gcc -print-multiarch', args) is None
+    assert handle_command_wrap('gcc test.c', args) == 'emcc test.c'
+    assert handle_command_wrap('gcc -shared -c test.o -o test.so', args) == \
+        'emcc -shared -c test.bc -o test.wasm'
+
+    # check ldflags injection
+    args = Args(cflags='', ldflags='-lm')
+    assert handle_command_wrap('gcc -shared -c test.o -o test.so', args) == \
+        'emcc -lm -shared -c test.bc -o test.wasm'
+
+    # compilation checks in numpy
+    assert handle_command_wrap('gcc /usr/file.c', args) is None