[builtin/bracket] Fix the overflow check to return status 2.

grr, it was returning 1 which is not a boolean!  Somehow tests didn't
catch that.

- refactor: Change spec test format.
- Also document the fact that we will change the 'test' builtin exit
  status with 'shopt -s simple_test_builtin'.  This allows people to do
  more precise error handling if they want.

doc/osh-quick-ref-toc.txt

@@ -149,7 +149,7 @@ SHELL OPTIONS
                   simple_word_eval       No splitting, static globbing
                   more_errexit           More errexit checks --  at command sub
                   X longopts             test -file, shopt -unset, etc.
-                  X simple_test_builtin  Only file tests (no strings), remove [
+                  X simple_test_builtin  Only file tests, remove [, status 2
   [Oil Syntax]    X all:parse
                   parse_at               echo @array @arrayfunc(x, y)
                   X parse_brace          cd ~/src { ... }

osh/expr_eval.py

@@ -693,15 +693,20 @@ def Eval(self, node):
           try:
             mode = posix.lstat(s).st_mode
           except OSError:
+            # TODO: simple_test_builtin should this as status=2.
+            #e_die("lstat() error: %s", e, word=node.child)
             return False
 
           return stat.S_ISLNK(mode)
 
         try:
           st = posix.stat(s)
-        except OSError:
-          # TODO: Signal extra debug information?
-          #log("Error from stat(%r): %s" % (s, e))
+        except OSError as e:
+          # TODO: simple_test_builtin should this as status=2.
+          # Problem: we really need errno, because test -f / is bad argument,
+          # while test -f /nonexistent is a good argument but failed.  Gah.
+          # ENOENT vs. ENAMETOOLONG.
+          #e_die("stat() error: %s", e, word=node.child)
           return False
         mode = st.st_mode
 
@@ -765,7 +770,7 @@ def Eval(self, node):
             return posix.isatty(fd)
           # fd is user input, and causes this exception in the binding.
           except OverflowError:
-            return 1
+            e_die('File descriptor %r is too big', s, word=node.child)
 
         # See whether 'set -o' options have been set
         if op_id == Id.BoolUnary_o:

spec/builtin-bracket.test.sh

@@ -13,21 +13,35 @@ echo status=$?
 echo status=$?
 [ '(' ]
 echo status=$?
-## stdout-json: "status=0\nstatus=0\nstatus=0\nstatus=0\n"
+## STDOUT: 
+status=0
+status=0
+status=0
+status=0
+## END
 
 #### one arg: empty string is false.  Equivalent to -n.
 test 'a'  && echo true
 test ''   || echo false
-## stdout-json: "true\nfalse\n"
+## STDOUT:
+true
+false
+## END
 
 #### -a as unary operator (alias of -e)
 # NOT IMPLEMENTED FOR OSH, but could be later.  See comment in core/id_kind.py.
 [ -a / ]
 echo status=$?
 [ -a /nonexistent ]
 echo status=$?
-## stdout-json: "status=0\nstatus=1\n"
-## N-I dash stdout-json: "status=2\nstatus=2\n"
+## STDOUT:
+status=0
+status=1
+## END
+## N-I dash STDOUT:
+status=2
+status=2
+## END
 
 #### two args: -z with = ! ( ]
 [ -z = ]
@@ -38,7 +52,12 @@ echo status=$?
 echo status=$?
 [ -z '(' ]
 echo status=$?
-## stdout-json: "status=1\nstatus=1\nstatus=1\nstatus=1\n"
+## STDOUT: 
+status=1
+status=1
+status=1
+status=1
+## END
 
 #### three args
 [ foo = '' ]
@@ -51,14 +70,23 @@ echo status=$?
 echo status=$?
 [ \( foo \) ]
 echo status=$?
-## stdout-json: "status=1\nstatus=1\nstatus=0\nstatus=0\nstatus=0\n"
+## STDOUT: 
+status=1
+status=1
+status=0
+status=0
+status=0
+## END
 
 #### four args
 [ ! foo = foo ]
 echo status=$?
 [ \( -z foo \) ]
 echo status=$?
-## stdout-json: "status=1\nstatus=1\n"
+## STDOUT: 
+status=1
+status=1
+## END
 
 #### test with extra args is syntax error
 test -n x ]
@@ -92,7 +120,10 @@ status=2
 #### -n
 test -n 'a'  && echo true
 test -n ''   || echo false
-## stdout-json: "true\nfalse\n"
+## STDOUT:
+true
+false
+## END
 
 #### ! -a
 [ -z '' -a ! -z x ]
@@ -117,25 +148,39 @@ command [ -z '' -a '(' ! -z x ')' ] && echo true
 #### == is alias for =
 [ a = a ] && echo true
 [ a == a ] && echo true
-## stdout-json: "true\ntrue\n"
-## BUG dash stdout-json: "true\n"
+## STDOUT: 
+true
+true
+## END
+## BUG dash STDOUT: 
+true
+## END
 ## BUG dash status: 2
 
 #### == and = does not do glob
 [ abc = 'a*' ]
 echo status=$?
 [ abc == 'a*' ]
 echo status=$?
-## stdout-json: "status=1\nstatus=1\n"
-## N-I dash stdout-json: "status=1\nstatus=2\n"
+## STDOUT:
+status=1
+status=1
+## END
+## N-I dash STDOUT:
+status=1
+status=2
+## END
 
 #### [ with op variable
 # OK -- parsed AFTER evaluation of vars
 op='='
 [ a $op a ] && echo true
 [ a $op b ] || echo false
 ## status: 0
-## stdout-json: "true\nfalse\n"
+## STDOUT:
+true
+false
+## END
 
 #### [ with unquoted empty var
 empty=''
@@ -147,7 +192,10 @@ empty=''
 var=-f
 [ $var = -f ] && echo true
 [ '-f' = $var ] && echo true
-## stdout-json: "true\ntrue\n"
+## STDOUT:
+true
+true
+## END
 
 #### [ '(' foo ] is runtime syntax error
 [ '(' foo ]
@@ -158,7 +206,11 @@ echo status=$?
 [ -z ] && echo true  # -z is operand
 [ -z '>' ] || echo false  # -z is operator
 [ -z '>' -- ] && echo true  # -z is operand
-## stdout-json: "true\nfalse\ntrue\n"
+## STDOUT:
+true
+false
+true
+## END
 
 #### operator/operand ambiguity with ]
 # bash parses this as '-z' AND ']', which is true.  It's a syntax error in
@@ -183,7 +235,10 @@ test -d $TMP
 echo status=$?
 test -d $TMP/__nonexistent_Z_Z__
 echo status=$?
-## stdout-json: "status=0\nstatus=1\n"
+## STDOUT:
+status=0
+status=1
+## END
 
 #### -x
 rm -f $TMP/x
@@ -192,15 +247,22 @@ test -x $TMP/x || echo 'no'
 chmod +x $TMP/x
 test -x $TMP/x && echo 'yes'
 test -x $TMP/__nonexistent__ || echo 'bad'
-## stdout-json: "no\nyes\nbad\n"
+## STDOUT:
+no
+yes
+bad
+## END
 
 #### -r
 echo '1' > $TMP/testr_yes
 echo '2' > $TMP/testr_no
 chmod -r $TMP/testr_no  # remove read permission
 test -r $TMP/testr_yes && echo 'yes'
 test -r $TMP/testr_no || echo 'no'
-## stdout-json: "yes\nno\n"
+## STDOUT:
+yes
+no
+## END
 
 #### -w
 rm -f $TMP/testw_*
@@ -209,7 +271,10 @@ echo '2' > $TMP/testw_no
 chmod -w $TMP/testw_no  # remove write permission
 test -w $TMP/testw_yes && echo 'yes'
 test -w $TMP/testw_no || echo 'no'
-## stdout-json: "yes\nno\n"
+## STDOUT:
+yes
+no
+## END
 
 #### -h and -L test for symlink
 tmp=$TMP/builtin-test-1
@@ -399,3 +464,13 @@ same
 different
 different
 ## END
+
+#### Overflow error
+test -t 12345678910
+echo status=$?
+## STDOUT:
+status=2
+## END
+## OK dash/bash STDOUT:
+status=1
+## END