vm: tests and fixes for exceptions

 * Add IsSet method to ExceptionInfo and use it to fix bad tests * Correct raise handling * Correct exception handling * Add finished marker to the tests to detect silent early exit * Still some exceptions tests failing

Author: ncw

py/exception.go

@@ -119,6 +119,11 @@ func (exc *ExceptionInfo) TracebackDump(w io.Writer){
 fmt.Fprintf(w, "%v: %v\n", exc.Type.Name, exc.Value)
 }
 
+// Test for being set
+func (exc*ExceptionInfo) IsSet() bool{
+returnexc.Type!=nil
+}
+
 // ExceptionNew
 funcExceptionNew(metatype*Type, argsTuple, kwargsStringDict) Object{
 iflen(kwargs) !=0{
@@ -229,7 +234,7 @@ func ExceptionGivenMatches(err, exc Object) bool{
 
 // Test the tuple case recursively
 ifexcTuple, ok:=exc.(Tuple); ok{
-fori:=0; i<len(excTuple); i++{
+fori:=rangeexcTuple{
 ifExceptionGivenMatches(err, excTuple[i]){
 returntrue
  }

vm/eval.go

@@ -660,6 +660,8 @@ func do_END_FINALLY(vm *Vm, arg int32){
 switchvm.exit{
 caseexitYield:
 panic("Unexpected exitYield in END_FINALLY")
+caseexitException:
+panic("Unexpected exitException in END_FINALLY")
 caseexitReturn, exitContinue:
 vm.result=vm.POP()
 caseexitSilenced:
@@ -689,7 +691,7 @@ func do_END_FINALLY(vm *Vm, arg int32){
  } else{
 vm.ClearException()
  }
-
+debugf("END_FINALLY: vm.exit = %v\n", vm.exit)
 }
 
 // Loads the __build_class__ helper function to the stack which
@@ -1201,7 +1203,7 @@ func do_DELETE_DEREF(vm *Vm, i int32){
 func (vm*Vm) raise(exc, cause py.Object){
 ifexc==nil{
 // raise (with no parameters == re-raise)
-ifvm.exc.Value==nil{
+if!vm.exc.IsSet(){
 vm.SetException(py.ExceptionNewf(py.RuntimeError, "No active exception to reraise"))
  } else{
 // Signal the existing exception again
@@ -1211,6 +1213,7 @@ func (vm *Vm) raise(exc, cause py.Object){
 // raise <instance>
 // raise <type>
 excException:=py.MakeException(exc)
+debugf("raise: excException = %v\n", excException)
 vm.SetException(excException)
 ifcause!=nil{
 excException.Cause=py.MakeException(cause)
@@ -1431,24 +1434,17 @@ func (vm *Vm) UnwindBlock(frame *py.Frame, block *py.TryBlock){
 
 // Unwinds the stack in the presence of an exception
 func (vm*Vm) UnwindExceptHandler(frame*py.Frame, block*py.TryBlock){
+debugf("** UnwindExceptHandler stack depth %v\n", vm.STACK_LEVEL())
 ifvm.STACK_LEVEL() <block.Level+3{
 panic("Couldn't find traceback on stack")
  } else{
 frame.Stack=frame.Stack[:block.Level+3]
  }
-// If have just raised an exception, don't overwrite it
-//
-// FIXME if have two exceptions python shows both tracebacks
-//
-// FIXME this is a departure from python's way not sure it is
-// correct
-ifvm.exc.Value!=nil{
-vm.DROPN(3)
- } else{
-vm.exc.Type=vm.POP().(*py.Type)
-vm.exc.Value=vm.POP()
-vm.exc.Traceback=vm.POP().(*py.Traceback)
- }
+debugf("** UnwindExceptHandler stack depth now %v\n", vm.STACK_LEVEL())
+vm.exc.Type=vm.POP().(*py.Type)
+vm.exc.Value=vm.POP()
+vm.exc.Traceback=vm.POP().(*py.Traceback)
+debugf("** UnwindExceptHandler exc = (type: %v, value: %v, traceback: %v)\n", vm.exc.Type, vm.exc.Value, vm.exc.Traceback)
 }
 
 // Run the virtual machine on a Frame object
@@ -1534,13 +1530,13 @@ func RunFrame(frame *py.Frame) (res py.Object, err error){
 frame.Lasti=b.Handler
 break
  }
-ifvm.exit&(exitException|exitReraise) !=0&& (b.Type==SETUP_EXCEPT||b.Type==SETUP_FINALLY){
+if(vm.exit==exitException||vm.exit==exitReraise)&& (b.Type==SETUP_EXCEPT||b.Type==SETUP_FINALLY){
 debugf("*** Exception\n")
 handler:=b.Handler
 // This invalidates b
 frame.PushBlock(EXCEPT_HANDLER, -1, vm.STACK_LEVEL())
-vm.PUSH(vm.old_exc.Traceback)
-vm.PUSH(vm.old_exc.Value)
+vm.PUSH(vm.exc.Traceback)
+vm.PUSH(vm.exc.Value)
 vm.PUSH(vm.exc.Type) // can be nil
 // FIXME PyErr_Fetch(&exc, &val, &tb)
 exc:=vm.exc.Type
@@ -1563,7 +1559,7 @@ func RunFrame(frame *py.Frame) (res py.Object, err error){
 break
  }
 ifb.Type==SETUP_FINALLY{
-ifvm.exit&(exitReturn|exitContinue) !=0{
+ifvm.exit==exitReturn||vm.exit==exitContinue{
 vm.PUSH(vm.result)
  }
 vm.PUSH(py.Int(vm.exit))
@@ -1573,7 +1569,7 @@ func RunFrame(frame *py.Frame) (res py.Object, err error){
  }
  }
  }
-ifvm.exc.Value!=nil{
+ifvm.exc.IsSet(){
 returnvm.result, vm.exc
  }
 returnvm.result, nil

vm/stringer.go

@@ -0,0 +1,16 @@
+// generated by stringer -type=vmExit -output stringer.go; DO NOT EDIT
+
+package vm
+
+import"fmt"
+
+const_vmExit_name="exitNotexitExceptionexitReraiseexitReturnexitBreakexitContinueexitYieldexitSilenced"
+
+var_vmExit_index= [...]uint8{0, 7, 20, 31, 41, 50, 62, 71, 83}
+
+func (ivmExit) String() string{
+ifi+1>=vmExit(len(_vmExit_index)){
+returnfmt.Sprintf("vmExit(%d)", i)
+ }
+return_vmExit_name[_vmExit_index[i]:_vmExit_index[i+1]]
+}

vm/tests/class.py

@@ -46,3 +46,5 @@ def method1(self, x):
 c=x()
 assertc.method1(1) ==2
 
+# End with this
+finished=True

vm/tests/comprehensions.py

@@ -25,3 +25,6 @@
 A={"a":1, "b":2, "c":3}
 B={k:kforkin ("a","b","c") }
 assertB["b"] =="b"
+
+# End with this
+finished=True

vm/tests/exceptions.py

@@ -0,0 +1,148 @@
+#!/usr/bin/env python3.4
+
+# Test exceptions
+
+# Straight forward
+ok=False
+try:
+raiseValueError
+exceptValueError:
+ok=True
+assertok
+
+ok=False
+try:
+raiseValueError
+exceptValueErrorase:
+ok=True
+assertok
+
+ok=False
+try:
+raiseValueError
+exceptValueErrorase:
+ok=True
+assertok
+
+ok=False
+try:
+raiseValueError
+except (IOError, ValueError) ase:
+ok=True
+assertok
+
+ok=False
+try:
+raiseValueError("Potato")
+except (IOError, ValueError) ase:
+ok=True
+assertok
+
+# hierarchy
+# FIXME doesn't work because IsSubtype is broken ValueError.IsSubtype(Exception) == false
+# ok = False
+# try:
+# raise ValueError("potato")
+# except Exception:
+# ok = True
+# assert ok
+
+ok=False
+try:
+raiseValueError
+exceptIOError:
+assertFalse, "Not expecting IO Error"
+exceptValueError:
+ok=True
+assertok
+
+# no exception
+ok=False
+try:
+pass
+exceptValueError:
+assertFalse, "Not expecting ValueError"
+else:
+ok=True
+assertok
+
+# nested
+ok=False
+try:
+try:
+raiseValueError("potato")
+exceptIOErrorase:
+assertFalse, "Not expecting IOError"
+else:
+assertFalse, "Expecting ValueError"
+exceptValueError:
+ok=True
+else:
+assertFalse, "Expecting ValueError (outer)"
+assertok
+
+ok1=False
+ok2=False
+try:
+try:
+raiseIOError("potato")
+exceptIOErrorase:
+ok1=True
+else:
+assertFalse, "Expecting ValueError"
+exceptValueError:
+assertFalse, "Expecting IOError"
+exceptIOError:
+assertFalse, "Expecting IOError"
+else:
+ok2=True
+assertok
+
+# re-raise
+ok1=False
+ok2=False
+try:
+try:
+raiseValueError("potato")
+exceptValueErrorase:
+ok2=True
+raise
+else:
+assertFalse, "Expecting ValueError (inner)"
+exceptValueError:
+ok1=True
+else:
+assertFalse, "Expecting ValueError (outer)"
+assertok1andok2
+
+# try/finally
+ok1=False
+ok2=False
+ok3=False
+try:
+try:
+ok1=True
+finally:
+ok2=True
+exceptValueError:
+assertFalse, "Not expecting ValueError (outer)"
+else:
+ok3=True
+assertok1andok2andok3
+
+# FIXME
+# ok1 = False
+# ok2 = False
+# try:
+# try:
+# raise ValueError()
+# finally:
+# ok1 = True
+# except ValueError:
+# ok2 = True
+# else:
+# assert False, "Expecting ValueError (outer)"
+# assert ok1 and ok2
+
+# End with this
+finished=True

vm/tests/functions.py

@@ -153,3 +153,7 @@ def fn12(*args,a=2,b=3,**kwargs) -> "RET":
 
 
 #FIXME decorators
+
+
+# End with this
+finished=True

vm/tests/ops.py

@@ -92,3 +92,37 @@
 assertTrueisTrue
 assertTrueisnotFalse
 # FIXME EXC_MATCH
+
+# logical
+t=True
+f=False
+assert (fandf) ==False
+assert (fandt) ==False
+assert (tandf) ==False
+assert (tandt) ==True
+
+assert (fandfandf) ==False
+assert (fandfandt) ==False
+assert (fandtandf) ==False
+assert (fandtandt) ==False
+assert (tandfandf) ==False
+assert (tandfandt) ==False
+assert (tandtandf) ==False
+assert (tandtandt) ==True
+
+assert (forf) ==False
+assert (fort) ==True
+assert (torf) ==True
+assert (tort) ==True
+
+assert (forforf) ==False
+assert (forfort) ==True
+assert (fortorf) ==True
+assert (fortort) ==True
+assert (torforf) ==True
+assert (torfort) ==True
+assert (tortorf) ==True
+assert (tortort) ==True
+
+# End with this
+finished=True

vm/vm.go

@@ -5,19 +5,21 @@ import (
 "github.com/ncw/gpython/py"
 )
 
+//go:generate stringer -type=vmExit -output stringer.go
+
 // VM exit type
 typevmExitbyte
 
 // VM exit values
 const (
-exitNot=vmExit(iota)// No error
-exitException// Exception occurred
-exitReraise// Exception re-raised by 'finally'
-exitReturn// 'return' statement
-exitBreak// 'break' statement
-exitContinue// 'continue' statement
-exitYield// 'yield' operator
-exitSilenced// Exception silenced by 'with'
+exitNotvmExit=iota// No error
+exitException// Exception occurred
+exitReraise// Exception re-raised by 'finally'
+exitReturn// 'return' statement
+exitBreak// 'break' statement
+exitContinue// 'continue' statement
+exitYield// 'yield' operator
+exitSilenced// Exception silenced by 'with'
 )
 
 // Virtual machine state