Implement the 'type' builtin (just the '-t' case), with tests.

Used by setup.sh in Nix.

Addresses issue #26.

core/builtin.py

@@ -58,7 +58,7 @@
TRUE FALSE
COLON
TEST BRACKET
HELP
TYPE HELP
""".split())


@@ -197,6 +197,9 @@ def Resolve(argv0):
  elif argv0 == "[":
    return EBuiltin.BRACKET

  elif argv0 == "type":
    return EBuiltin.TYPE

  elif argv0 == "help":
    return EBuiltin.HELP

@@ -646,6 +649,61 @@ def Unset(argv, mem, funcs):
  return 0


TYPE_SPEC = _Register('type')
TYPE_SPEC.ShortFlag('-t')

def Type(argv, funcs, path_val):
  arg, i = TYPE_SPEC.Parse(argv)

  if path_val.tag == value_e.Str:
    path_list = path_val.s.split(':')
  else:
    path_list = []  # treat as empty path

  status = 0
  if not arg.t:
    util.warn("*** 'type' builtin called without -t ***")
    status = 1
    # Keep going anyway

  for name in argv[i:]:
    if name in funcs:
      print('function')
      continue

    if Resolve(name) != EBuiltin.NONE:
      print('builtin')
      continue
    if ResolveSpecial(name) != EBuiltin.NONE:
      print('builtin')
      continue
    if lex.IsOtherBuiltin(name):
      print('builtin')
      continue

    if lex.IsKeyword(name):
      print('keyword')
      continue

    # Now look for files.
    found = False
    for path_dir in path_list:
      full_path = os.path.join(path_dir, name)
      if os.path.exists(full_path):
        print('file')
        found = True
        break
    if found:
      continue

    # Name not found.  Nothing printed, but status is 1.
    #log('%r not found', name)
    status = 1

  return status



def Trap(argv, traps):
  # TODO: register trap

core/cmd_exec.py

@@ -297,6 +297,10 @@ def _RunBuiltin(self, builtin_id, argv):
    elif builtin_id == EBuiltin.BRACKET:
      status = test_builtin.Test(argv, True)  # need_right_bracket

    elif builtin_id == EBuiltin.TYPE:
      path = self.mem.GetVar('PATH')
      status = builtin.Type(argv, self.funcs, path)

    elif builtin_id == EBuiltin.HELP:
      loader = util.GetResourceLoader()
      status = builtin.Help(argv, loader)

osh/lex.py

@@ -181,7 +181,11 @@
  C('elif',     Id.KW_Elif),
  C('function', Id.KW_Function),
  C('time',     Id.KW_Time),
]

# These are treated like builtins in bash, but keywords in OSH.  However, we
# main compatibility with bash for the 'type' builtin.
_MORE_KEYWORDS = [
  C('declare',  Id.Assign_Declare),
  C('local',    Id.Assign_Local),
  C('readonly', Id.Assign_Readonly),
@@ -191,13 +195,27 @@
  C('return',   Id.ControlFlow_Return),
]


_TYPE_KEYWORDS = set(name for _, name, _ in _KEYWORDS)
_TYPE_KEYWORDS.add('{')  # not in our lexer list
_TYPE_BUILTINS = set(name for _, name, _ in _MORE_KEYWORDS)


def IsOtherBuiltin(name):
  return name in _TYPE_BUILTINS


def IsKeyword(name):
  return name in _TYPE_KEYWORDS


# These two can must be recognized in the OUTER state, but can't nested within
# [[.
# Keywords have to be checked before _UNQUOTED so we get <KW_If "if"> instead
# of <Lit_Chars "if">.
LEXER_DEF[LexMode.OUTER] = [
  C('((', Id.Op_DLeftParen),  # not allowed within [[
] + _KEYWORDS + _UNQUOTED
] + _KEYWORDS + _MORE_KEYWORDS + _UNQUOTED

# DBRACKET: can be like OUTER, except:
# - Don't really need redirects either... Redir_Less could be Op_Less

spec/builtin-type.test.sh

@@ -0,0 +1,27 @@
#!/bin/bash
#
# Bash implements type -t.
# 
# NOTE: Aliases don't work in batch mode!  Interactive only.

### type -t builtin -> function
f() { echo hi; }
type -t f
# stdout-json: "function\n"

### type -t builtin -> builtin
type -t echo read : [ declare local break continue
# stdout-json: "builtin\nbuiltin\nbuiltin\nbuiltin\nbuiltin\nbuiltin\nbuiltin\nbuiltin\n"

### type -t builtin -> keyword
type -t for time ! fi do {
# stdout-json: "keyword\nkeyword\nkeyword\nkeyword\nkeyword\nkeyword\n"

### type -t builtin -> file
type -t find xargs
# stdout-json: "file\nfile\n"

### type -t builtin -> not found
type -t echo ZZZ find =
echo status=$?
# stdout-json: "builtin\nfile\nstatus=1\n"

test/spec.sh

@@ -262,6 +262,12 @@ builtin-vars() {
    ${REF_SHELLS[@]} $OSH "$@"
}

# Bash impleement type -t, but no other shell does.  For Nix.
builtin-type() {
  sh-spec spec/builtin-type.test.sh \
    $BASH $OSH "$@"
}

builtins-special() {
  sh-spec spec/builtins-special.test.sh --osh-failures-allowed 3 \
    ${REF_SHELLS[@]} $OSH "$@"