[translation] Fix 32-bit truncation in (( status and for (( condition

Bugs reported by Koiche Murase on Zulip.

- We are still using mops.BigTruncate() in BashArray indexing and slicing.
  - However that data structure may change, so I'm not touching it right
    now.
- The printf bug still needs to be fixed.  It's because we use 32-bit
  to_int() rather than 64-bit mops::FromStr().

Author: Andy C

builtin/printf_osh.py

@@ -312,6 +312,9 @@ def _Format(self, parts, varargs, locs, out):
 
                         try:
                             # note: spaces like ' -42 ' accepted and normalized
+                            # TODO: use mops.FromStr()
+                            # And mylib.hex_lower() etc. may have to change
+
                             d = int(s)
                         except ValueError:
                             # 'a is interpreted as the ASCII value of 'a'
@@ -352,8 +355,8 @@ def _Format(self, parts, varargs, locs, out):
                             # state.
 
                             tzcell = self.mem.GetCell('TZ')
-                            if tzcell and tzcell.exported and tzcell.val.tag(
-                            ) == value_e.Str:
+                            if (tzcell and tzcell.exported and
+                                    tzcell.val.tag() == value_e.Str):
                                 tzval = cast(value.Str, tzcell.val)
                                 posix.putenv('TZ', tzval.s)
 

osh/cmd_eval.py

@@ -83,6 +83,7 @@
 from osh import braces
 from osh import sh_expr_eval
 from osh import word_eval
+from mycpp import mops
 from mycpp import mylib
 from mycpp.mylib import log, probe, switch, tagswitch
 from ysh import expr_eval
@@ -1251,8 +1252,8 @@ def _DoForExpr(self, node):
             while True:
                 if for_cond:
                     # We only accept integers as conditions
-                    cond_int = self.arith_ev.EvalToInt(for_cond)
-                    if cond_int == 0:  # false
+                    cond_int = self.arith_ev.EvalToBigInt(for_cond)
+                    if mops.Equal(cond_int, mops.ZERO):  # false
                         break
 
                 try:
@@ -1574,8 +1575,8 @@ def _Dispatch(self, node, cmd_st):
 
                 cmd_st.check_errexit = True
                 cmd_st.show_code = True  # this is a "leaf" for errors
-                i = self.arith_ev.EvalToInt(node.child)
-                status = 1 if i == 0 else 0
+                i = self.arith_ev.EvalToBigInt(node.child)
+                status = 1 if mops.Equal(i, mops.ZERO) else 0
 
             elif case(command_e.ControlFlow):  # LEAF command
                 node = cast(command.ControlFlow, UP_node)

spec/bugs.test.sh

@@ -367,7 +367,7 @@ printf '%u\n' 2147483648
 2147483648
 ## END
 
-#### bit shift bug (Koiche on Zulip)
+#### (( status bug
 case $SH in dash|ash) exit ;; esac
 
 (( 1 << 32 ))

spec/for-expr.test.sh

@@ -116,3 +116,58 @@ for ((i = $"3"; i < $"5"; ++i)); do echo $i; done
 ## OK zsh STDOUT:
 ## END
 
+
+#### Integers near 31, 32, 62 bits
+
+# Hm this was never a bug, but it's worth testing.
+# The bug was EvalToInt() in the condition.
+
+for base in 31 32 62; do
+
+  start=$(( (1 << $base) - 2))
+  end=$(( (1 << $base) + 2))
+
+  for ((i = start; i < end; ++i)); do
+    echo $i
+  done
+  echo ---
+done
+
+## STDOUT:
+2147483646
+2147483647
+2147483648
+2147483649
+---
+4294967294
+4294967295
+4294967296
+4294967297
+---
+4611686018427387902
+4611686018427387903
+4611686018427387904
+4611686018427387905
+---
+## END
+
+
+#### Condition that's greater than 32 bits
+
+iters=0
+
+for ((i = 1 << 32; i; ++i)); do
+  echo $i
+  iters=$(( iters + 1 ))
+  if test $iters -eq 5; then
+    break
+  fi
+done
+
+## STDOUT:
+4294967296
+4294967297
+4294967298
+4294967299
+4294967300
+## END