re-run analysis in Python tests with cached results when TEST_CPPCHECK_INJECT_BUILDDIR is specified

Author: firewave

test/cli/testutils.py

@@ -5,6 +5,7 @@
 import subprocess
 import time
 import tempfile
+import pathlib
 
 # Create Cppcheck project file
 import sys
@@ -205,11 +206,40 @@ def cppcheck_ex(args, env=None, remove_checkers_report=True, cwd=None, cppcheck_
 
     logging.info(exe + ' ' + ' '.join(args))
 
-    run_subprocess = __run_subprocess_tty if tty else __run_subprocess
-    return_code, stdout, stderr = run_subprocess([exe] + args, env=env, cwd=cwd, timeout=timeout)
+    def run_cppcheck():
+        run_subprocess = __run_subprocess_tty if tty else __run_subprocess
+        rc, out, err = run_subprocess([exe] + args, env=env, cwd=cwd, timeout=timeout)
 
-    stdout = stdout.decode(encoding='utf-8', errors='ignore').replace('\r\n', '\n')
-    stderr = stderr.decode(encoding='utf-8', errors='ignore').replace('\r\n', '\n')
+        out = out.decode(encoding='utf-8', errors='ignore').replace('\r\n', '\n')
+        err = err.decode(encoding='utf-8', errors='ignore').replace('\r\n', '\n')
+
+        return rc, out, err
+
+    return_code, stdout, stderr = run_cppcheck()
+
+    if 'TEST_CPPCHECK_INJECT_BUILDDIR' in os.environ:
+        # run it again with the generated cache and make sure the output is identical
+
+        def get_cache_contents():
+            content = {}
+            for dirpath, dirnames, filenames in os.walk(builddir_tmp.name):
+                for fn in filenames:
+                    content[os.path.join(dirpath, fn)] = (pathlib.Path(builddir_tmp.name) / dirpath / fn).read_text()
+                for dn in dirnames:
+                    content[os.path.join(dirpath, dn)] = None
+            return content
+
+        cache_content = get_cache_contents()
+
+        return_code_1, stdout_1, stderr_1 = run_cppcheck()
+
+        assert return_code == return_code_1, 'exitcode different with cached results'
+        assert stdout == stdout_1, 'stdout different with cached results'
+        assert stderr == stderr_1, 'stderr different with cached results'
+
+        cache_content_1 = get_cache_contents()
+
+        assert cache_content == cache_content_1, 'cache contents changed in-between runs'
 
     if builddir_tmp:
         builddir_tmp.cleanup()