fix bug with filenames of stdlib modules

Author: skogsbaer

python/code/wypp/instrument.py

@@ -140,19 +140,23 @@ def find_spec(
             target: types.ModuleType | None = None,
         ) -> ModuleSpec | None:
 
+        debug(f'Consulting InstrumentingFinder.find_spec for fullname={fullname}')
         # 1) The fullname is the name of the main module. This might be a dotted name such as x.y.z.py
         #    so we have special logic here
         fp = os.path.join(self.modDir, f"{fullname}.py")
         if self.mainModName == fullname and os.path.isfile(fp):
             loader = InstrumentingLoader(fullname, fp)
-            return spec_from_file_location(fullname, fp, loader=loader)
+            spec = spec_from_file_location(fullname, fp, loader=loader)
+            debug(f'spec for {fullname}: {spec}')
+            return spec
         # 2) The fullname is a prefix of the main module. We want to load main modules with
         #    dotted names such as x.y.z.py, hence we synthesize a namespace pkg
         #    e.g. if 'x.y.z.py' exists and we're asked for 'x', return a package spec.
         elif self.mainModName.startswith(fullname + '.'):
             spec = importlib.machinery.ModuleSpec(fullname, loader=None, is_package=True)
             # Namespace package marker (PEP 451)
             spec.submodule_search_locations = []
+            debug(f'spec for {fullname}: {spec}')
             return spec
         # 3) Fallback: use the original PathFinder
         spec = self._origFinder.find_spec(fullname, path, target)
@@ -191,10 +195,19 @@ def setupFinder(modDir: str, modName: str, extraDirs: list[str], typechecking: b
         # Create and install our custom finder
         instrumenting_finder = InstrumentingFinder(finder, modDir, modName, extraDirs)
         sys.meta_path.insert(0, instrumenting_finder)
+        debug(f'Installed instrument finder {instrumenting_finder}')
+
+        alreadyLoaded = sys.modules.get(modName)
+        if alreadyLoaded:
+            sys.modules.pop(modName, None)
+            importlib.invalidate_caches()
 
         try:
             yield
         finally:
+            if alreadyLoaded:
+                sys.modules[modName] = alreadyLoaded
+
             # Remove our custom finder when exiting the context
             if instrumenting_finder in sys.meta_path:
                 sys.meta_path.remove(instrumenting_finder)

python/code/wypp/runCode.py

@@ -34,7 +34,7 @@ def __init__(self, mod, properlyImported):
 @dataclass
 class RunSetup:
     def __init__(self, pathDir: str, args: list[str]):
-        self.pathDir = pathDir
+        self.pathDir = os.path.abspath(pathDir)
         self.args = args
         self.sysPathInserted = False
         self.oldArgs = sys.argv
@@ -64,12 +64,30 @@ def prepareLib(onlyCheckRunnable, enableTypeChecking):
                        quiet=onlyCheckRunnable)
     return libDefs
 
+def debugModule(name):
+    if name in sys.modules:
+        m = sys.modules["copy"]
+        print(f"Module {name} already loaded from:", getattr(m, "__file__", None))
+    print("CWD:", os.getcwd())
+    print("sys.path[0]:", sys.path[0])
+    print("First few sys.path entries:")
+    for p in sys.path[:5]:
+        print("  ", p)
+
+    spec = importlib.util.find_spec(name)
+    print("Resolved spec:", spec)
+    if spec:
+        print("Origin:", spec.origin)
+        print("Loader:", type(spec.loader).__name__)
+
 def runCode(fileToRun, globals, doTypecheck=True, extraDirs=None) -> dict:
     if not extraDirs:
         extraDirs = []
     modName = os.path.basename(os.path.splitext(fileToRun)[0])
     with instrument.setupFinder(os.path.dirname(fileToRun), modName, extraDirs, doTypecheck):
         sys.dont_write_bytecode = True
+        if DEBUG:
+            debugModule(modName)
         res = runpy.run_module(modName, init_globals=globals, run_name='__wypp__', alter_sys=False)
         return res
 

python/code/wypp/runner.py

@@ -66,9 +66,14 @@ def main(globals, argList=None):
             sys.exit(1)
 
     fileToRun: str = args.file
+    if not os.path.exists(fileToRun):
+        printStderr(f'File {fileToRun} does not exist')
+        sys.exit(1)
     if args.changeDir:
-        os.chdir(os.path.dirname(fileToRun))
+        d = os.path.dirname(fileToRun)
+        os.chdir(d)
         fileToRun = os.path.basename(fileToRun)
+        debug(f'Changed directory to {d}, fileToRun={fileToRun}')
 
     isInteractive = args.interactive
     version = versionMod.readVersion()
@@ -81,13 +86,15 @@ def main(globals, argList=None):
 
     libDefs = runCode.prepareLib(onlyCheckRunnable=args.checkRunnable, enableTypeChecking=args.checkTypes)
 
-    with (runCode.RunSetup(os.path.dirname(fileToRun), [fileToRun] + restArgs),
+    runDir = os.path.dirname(fileToRun)
+    with (runCode.RunSetup(runDir, [fileToRun] + restArgs),
           paths.projectDir(os.path.abspath(os.getcwd()))):
         globals['__name__'] = '__wypp__'
         sys.modules['__wypp__'] = sys.modules['__main__']
         loadingFailed = False
         try:
             verbose(f'running code in {fileToRun}')
+            debug(f'sys.path: {sys.path}')
             globals['__file__'] = fileToRun
             globals = runCode.runStudentCode(fileToRun, globals, args.checkRunnable,
                                              doTypecheck=args.checkTypes, extraDirs=args.extraDirs)

python/file-test-data/basics/async2_ok.py

@@ -0,0 +1,24 @@
+from typing import *
+import types
+import asyncio
+from datetime import datetime
+
+def debug(msg):
+    print(msg)
+
+async def meaningOfLife(x: str) -> int:
+    debug(f'At start of meaningOfLife: {x}')
+    await asyncio.sleep(0.0001)
+    debug(f'At end of meaningOfLife: {x}')
+    return 42
+
+async def run() -> None:
+    a = meaningOfLife('a')
+    debug('coroutine object')
+    n = await a
+    debug(n)
+
+def main():
+    asyncio.run(run())
+
+main()

python/file-test-data/basics/copy.out

@@ -0,0 +1 @@
+Hello copy

python/file-test-data/basics/copy.py

@@ -0,0 +1,4 @@
+# WYPP_TEST_CONFIG: {"args": ["--change-directory"], "exitCode": 0}
+
+# This file intentionally has the same name as a file from the stdlib
+print('Hello copy')

python/file-test-data/basics/typing.err

@@ -0,0 +1 @@
+File file-test-data/basics/typing.py does not exist

python/fileTests.py

@@ -1,6 +1,7 @@
 from pathlib import Path
 from fileTestsLib import *
 import sys
+import os
 
 def pythonMinVersion(major: int, minor: int) -> bool:
     return sys.version_info >= (major, minor)
@@ -33,7 +34,15 @@ def main():
 
     globalCtx.results.finish()
 
+def extraChecks():
+    # The localTyping file does not exist, running should thus fail
+    localTyping = 'file-test-data/basics/typing.py'
+    if os.path.exists(localTyping):
+        raise ValueError(f'File {localTyping} should not exist')
+    check(localTyping, exitCode=1)
+
 try:
     main()
+    extraChecks()
 except KeyboardInterrupt:
     pass

python/fileTestsLib.py

@@ -12,6 +12,12 @@
 import re
 import fnmatch
 
+DEBUG = False
+
+def debug(s):
+    if DEBUG:
+        print(f'[TESTDEBUG] {s}')
+
 GLOBAL_CHECK_OUTPUTS = True
 
 GLOBAL_RECORD_ALL = False # Should be False, write actual output to all expected output files
@@ -34,6 +40,7 @@ def parseArgs() -> TestOpts:
     )
 
     # Define the command-line arguments
+    parser.add_argument("--debug", action="store_true", help="Output debug messages")
     parser.add_argument("--start-at", type=str, help="Start with test in FILE")
     parser.add_argument("--only", type=str, help="Run only the test in FILE")
     parser.add_argument("--continue", action="store_true",
@@ -48,7 +55,9 @@ def parseArgs() -> TestOpts:
                         nargs='*')
     # Parse the arguments
     args = parser.parse_args()
-
+    if args.debug:
+        global DEBUG
+        DEBUG = True
     scriptDir = os.path.dirname(__file__)
     return TestOpts(
         cmd=f'{scriptDir}/code/wypp/runYourProgram.py',
@@ -244,6 +253,7 @@ def _runTest(testFile: str,
     env = os.environ.copy()
     env['PYTHONPATH'] = os.pathsep.join([os.path.join(ctx.opts.baseDir, 'code')] + pythonPath)
     env['WYPP_UNDER_TEST'] = 'True'
+    debug(' '.join(cmd))
     with open(actualStdoutFile, 'w') as stdoutFile, \
             open(actualStderrFile, 'w') as stderrFile:
         # Run the command
@@ -332,17 +342,20 @@ class WyppTestConfig:
     typecheck: Literal[True, False, "both"]
     args: list[str]
     pythonPath: Optional[str]
+    exitCode: Optional[int]
     @staticmethod
     def default() -> WyppTestConfig:
-        return WyppTestConfig(typecheck=True, args=[], pythonPath=None)
+        return WyppTestConfig(typecheck=True, args=[], pythonPath=None, exitCode=None)
 
 def readWyppTestConfig(path: str, *, max_lines: int = 5) -> WyppTestConfig:
     """
     Read a line like `# WYPP_TEST_CONFIG: {"typecheck": false}` from the first
     `max_lines` lines of the file at `path` and return it as a dict.
     Returns {} if not present.
     """
-    validKeys = ['typecheck', 'args', 'pythonPath']
+    validKeys = ['typecheck', 'args', 'pythonPath', 'exitCode']
+    if not os.path.exists(path):
+        return WyppTestConfig.default()
     with open(path, "r", encoding="utf-8") as f:
         for lineno in range(1, max_lines + 1):
             line = f.readline()
@@ -358,7 +371,10 @@ def readWyppTestConfig(path: str, *, max_lines: int = 5) -> WyppTestConfig:
                 typecheck = j.get('typecheck', True)
                 args = j.get('args', [])
                 pythonPath = j.get('pythonPath')
-                return WyppTestConfig(typecheck=typecheck, args=args, pythonPath=pythonPath)
+                exitCode = j.get('exitCode')
+                cfg = WyppTestConfig(typecheck=typecheck, args=args, pythonPath=pythonPath, exitCode=exitCode)
+                debug(f'Config for {path}: {cfg}')
+                return cfg
     return WyppTestConfig.default()
 
 def checkNoConfig(testFile: str,
@@ -370,8 +386,6 @@ def checkNoConfig(testFile: str,
           checkOutputs: bool = True,
           ctx: TestContext = globalCtx,
           what: str = ''):
-    if guessExitCode(testFile) == 0:
-        exitCode = 0
     status = _check(testFile, exitCode, typecheck, args, pythonPath, minVersion, checkOutputs, ctx, what)
     ctx.results.storeTestResult(testFile, status)
     if status == 'failed':
@@ -396,6 +410,10 @@ def check(testFile: str,
     pythonPath = []
     if cfg.pythonPath:
         pythonPath = cfg.pythonPath.split(':')
+    if cfg.exitCode is not None:
+        exitCode = cfg.exitCode
+    elif guessExitCode(testFile) == 0:
+        exitCode = 0
     if cfg.typecheck == 'both':
         checkNoConfig(testFile, exitCode, typecheck=True, args=args,
                       pythonPath=pythonPath, minVersion=minVersion, checkOutputs=checkOutputs,