twister: improve handling of ELF file parsing

We have been dealing with missing and multiple binaries the same way and
both would result in a build error, which is not accurate. multiple
binaries in the build directory are fine, we just need to pick the right
one for parsing.

If we get no binaries, raise an exception and report failure, however,
if we have multiple binaries, filter intermediate artifacts out and
parse what remains.

qemu binaries generated after a run are also being filtered here. Those
are not build artificats and appear only after running in qemu. However
they have been causing issues on retries.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

scripts/pylib/twister/twisterlib/runner.py

@@ -680,7 +680,8 @@ def determine_testcases(self, results):
         yaml_testsuite_name = self.instance.testsuite.id
         logger.debug(f"Determine test cases for test suite: {yaml_testsuite_name}")
 
-        elf = ELFFile(open(self.instance.get_elf_file(), "rb"))
+        elf_file = self.instance.get_elf_file()
+        elf = ELFFile(open(elf_file, "rb"))
 
         logger.debug(f"Test instance {self.instance.name} already has {len(self.instance.testcases)} cases.")
         new_ztest_unit_test_regex = re.compile(r"z_ztest_unit_test__([^\s]*)__([^\s]*)")
@@ -702,6 +703,7 @@ def determine_testcases(self, results):
                             detected_cases.append(testcase_id)
 
         if detected_cases:
+            logger.debug(f"{', '.join(detected_cases)} in {elf_file}")
             self.instance.testcases.clear()
             self.instance.testsuite.testcases.clear()
 

scripts/pylib/twister/twisterlib/testinstance.py

@@ -290,15 +290,17 @@ def get_elf_file(self) -> str:
             build_dir = self.build_dir
 
         fns = glob.glob(os.path.join(build_dir, "zephyr", "*.elf"))
-        fns.extend(glob.glob(os.path.join(build_dir, "zephyr", "*.exe")))
         fns.extend(glob.glob(os.path.join(build_dir, "testbinary")))
         blocklist = [
                 'remapped', # used for xtensa plaforms
                 'zefi', # EFI for Zephyr
-                '_pre' ]
+                'qemu', # elf files generated after running in qemu
+                '_pre']
         fns = [x for x in fns if not any(bad in os.path.basename(x) for bad in blocklist)]
-        if len(fns) != 1 and self.platform.type != 'native':
-            raise BuildError("Missing/multiple output ELF binary")
+        if not fns:
+            raise BuildError("Missing output binary")
+        elif len(fns) > 1:
+            logger.warning(f"multiple ELF files detected: {', '.join(fns)}")
         return fns[0]
 
     def get_buildlog_file(self) -> str: