Use PATH env variable when gcc found in PATH

tools/test/toolchains/api.py

@@ -4,15 +4,15 @@
 from string import printable
 from copy import deepcopy
 from mock import MagicMock, patch
-from hypothesis import given
-from hypothesis.strategies import text, lists, fixed_dictionaries
+from hypothesis import given, settings
+from hypothesis.strategies import text, lists, fixed_dictionaries, booleans
 
 ROOT = os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "..",
                                     ".."))
 sys.path.insert(0, ROOT)
 
 from tools.toolchains import TOOLCHAIN_CLASSES, LEGACY_TOOLCHAIN_NAMES,\
-    Resources
+    Resources, TOOLCHAIN_PATHS
 from tools.targets import TARGET_MAP
 
 def test_instantiation():
@@ -125,3 +125,21 @@ def test_detect_duplicates(filenames):
         assert "dupe.s" in notification["message"]
         assert "dupe.c" in notification["message"]
         assert "dupe.cpp" in notification["message"]
+
+@given(text(alphabet=ALPHABET + ["/"], min_size=1))
+@given(booleans())
+@given(booleans())
+@settings(max_examples=20)
+def test_path_specified_gcc(gcc_loc, exists_at_loc, exists_in_path):
+    with patch('tools.toolchains.gcc.exists') as _exists:
+        with patch('tools.toolchains.gcc.find_executable') as _find:
+            _exists.return_value = exists_at_loc
+            _find.return_value = exists_in_path
+            TOOLCHAIN_PATHS['GCC_ARM'] = gcc_loc
+            toolchain_class = TOOLCHAIN_CLASSES["GCC_ARM"]
+            found_p = toolchain_class.check_executable()
+            assert found_p == (exists_at_loc or exists_in_path)
+            if exists_at_loc:
+                assert TOOLCHAIN_PATHS['GCC_ARM'] == gcc_loc
+            elif exists_in_path:
+                assert TOOLCHAIN_PATHS['GCC_ARM'] == ''

tools/toolchains/gcc.py

@@ -15,7 +15,8 @@
 limitations under the License.
 """
 import re
-from os.path import join, basename, splitext, dirname
+from os.path import join, basename, splitext, dirname, exists
+from distutils.spawn import find_executable
 
 from tools.toolchains import mbedToolchain, TOOLCHAIN_PATHS
 from tools.hooks import hook_tool
@@ -285,7 +286,15 @@ def check_executable():
         """Returns True if the executable (arm-none-eabi-gcc) location
         specified by the user exists OR the executable can be found on the PATH.
         Returns False otherwise."""
-        return mbedToolchain.generic_check_executable("GCC_ARM", 'arm-none-eabi-gcc', 1)
+        if not TOOLCHAIN_PATHS['GCC_ARM'] or not exists(TOOLCHAIN_PATHS['GCC_ARM']):
+            if find_executable('arm-none-eabi-gcc'):
+                TOOLCHAIN_PATHS['GCC_ARM'] = ''
+                return True
+            else:
+                return False
+        else:
+            exec_name = join(TOOLCHAIN_PATHS['GCC_ARM'], 'arm-none-eabi-gcc')
+            return exists(exec_name) or exists(exec_name + '.exe')
 
 class GCC_ARM(GCC):
     pass